A growing number of scientists are convinced the future influences the past | Hacker News Reader

A growing number of scientists are convinced the future influences the past

vice.com

329 pointsmyth_drannon436 comments

> It may seem eerie to our brains, which process events sequentially, but the history of science is also littered with examples of human biases leading to bad conclusions, such as the Earth-centric model of the solar system.

Slow down. Assuming that time moves in one direction is not comparable to geocentrism.

It is because in both cases, you can work out that you'll never make an observation that really proves it one way or the other, but you might come up with some laws of physics that are more conveniently expressed in one way than another. They're both ultimately questions about your coordinate system, and in fact it is easier to invert time than it is to work out how everything's supposed to function in a rotating+sun-orbiting+precessing+... coordinate system.

If we reverse time and this implies running everything backwards in physics, do we include gravity in the set of things that are reversed? Then everything would fly off the face of the earth in reverse-time.

Gravity is a universal constant. If you reverse time, you just reverse the order of cause and effect, not what the effect is.

Does that make more sense to you?

If we reverse time, would gravitational waves flow backwards?

yes. it's literally like playing a movie in reverse.

" it's literally like playing a movie in reverse" seems overly authoritative for something we haven't observed. I have seen Tenet, but it's a work of fiction.

Have we observed reflected gravitational waves? In reverse-time, where would they originate from if they presumably rippled out into space and didn't collide with anything in forward-time?

.... they would "originate" from all the locations the gravity waves spread to and converge on the source.

Tenet has nothing to do with this- I'm just explaining it as it was covered in my many physics classes that covered the nature of the arrow of time (https://en.wikipedia.org/wiki/Arrow_of_time) and how I interpret it in terms of what seems most likely/least unlikely.

"gravity is a universal constant" contradicts Newtonian mechanics, special and general relativity.

In these "it's like taking a video of throwing a ball in the air and allowing it to land on the ground, then playing it in reverse" examples, I can't help but think of Newton's first law. If an object at rest stays at rest, how does the ball leap from the ground? Where does the impulse come from? Reverse time seems too far fetched for me, or at least the simplified naïve version of it does.

It also seems a bit misleading, since in that scenario a ball is intentionally thrown so that it comes down the same way.

Let's consider something else - imagine an accretion disk of space dust slowly pulling itself together to form a planet. Play that in reverse, and you have the a planet slowly coming apart piece by piece. Imagine reversing the impact that created the moon. The moon comes apart piece by piece, creating an accretion disk around the earth, which then all moves and hits one area of the earth, and there several parts of it (and part of the earth itself) move together to form a separate planet, which then launches itself from the earths surface into space, flies around the sun a few times, and then slowly breaks apart piece by piece into another accretion disk.

Let's check.

F = ma

F = m dv/dt

u = -t dv/dt = -dv/du

- F = m dv/du

If you stop there it looks like you're right, but you also must change the definition of velocity to account for the new time.

v = dx/dt = -dx/du

+F = m dx/du

So the direction of gravity (the force F) stays the same when you flip time. I can explain that without the math by pointing out that if you took a video of a ball being thrown up and caught and played it in reverse, it would still depict a ball being thrown up and caught.

> I can explain that without the math by pointing out that if you took a video of a ball being thrown up and caught and played it in reverse, it would still depict a ball being thrown up and caught.

That's amazing, thanks. The portion where you caught the ball in forward time is equivalent to throwing the ball in reverse time.

I need to rewatch Tenet some day

I watched it 4 times. Only then I started to understand what's happening. How great and unique this movie really is.

I felt like I understood it the first time, but didn't think it was very good. Was that your initial reaction?

If we change the analogy of throwing a ball to firing a gun into the air - does the analogy still work? Since when we fire the gun up, the bullet will travel faster up than it will travel down due to terminal velocity in forward time. How is that phenomenon explained in reverse time?

Instead of predominately striking the bullet in a way that causes it to slow down, the molecules in the air will predominately strike it in a way that causes it to move faster, in what looks like an unbelievable (but still physically possible) run of good luck.

In the way down -sky to gun - the molecules in the air will give it energy to accelerate more than gravity alone would. Before that - in the way up - air molecules will cause it to move upwards at constant speed until conveniently they stop doing so.

> unbelievable (but still physically possible)

Physically possible - but in the same sense that the second law is not a physical law.

So it seems like if we reverse time, we reverse entropy and that as time approaches 0, we would effectively be reversing the big bang and instead have the big collapse.

Another thought experiment that comes to mind is compressed gas in a cylinder. When we open the valve, the gas in the cylinder comes out. In reverse time, the gas would go back into the cannister and the valve would close after the gas went back in. Very low probability of that happening in forward time, though not not 0.

Though it seems weird, because why does the gas go into the cylinder? Because further into reverse-time, something sucked it all out (in forward-time, this machine is the compressor that put the gas in the cylider.) This hurts my brain!

What is u?

A newline is missing there, u = -t. (Too late to edit it.)

Reversing time on an attracting force still gives you an attractive force. Velocity is reversed, but acceleration isn't.

Imagine a ball being thrown up and then falling down, in a parabola. Reversing a video of that still gives you a video of a ball in a normal parabola trajectory.

The history of the universe channel on YouTube has an episode called 'what is time' that goes over symmetries like this. Lots of atomic/quantum scale interactions are time reversible like this, but not quote all, and that may be where time arrives from.

Well worth watching that episode as it does far better explaining than I do.

It isn't because we have the observations we have. It might be mathematically easy to invert time, but empirically it's not so simple. Mathematical symmetries and expressions are nice, but then the actual physical consequences and requirements (e.g., material, time, energy inputs) sort of force one's hand.

Also, geocentrism is actually disproven by numerous observations, which in fact guided the mathematical formulation of our current physics.

One thing is (almost) certain: the laws of physics as we know them (i.e. the Standard Model and General Relativity) are incomplete ("wrong"). That doesn't mean any old model is equivalent or as useful as either, though.

>Also, geocentrism is actually disproven by numerous observations, which in fact guided the mathematical formulation of our current physics.

The validity of a coordinate system with the earth stationary at the center is guaranteed by the general principle of relativity. To get the stars to circle around it you would add a radially increasing potential in classical mechanics, or some coordinate shenanigans in GR. These coordinate systems are used in aerospace engineering to get convenient expressions of L1 points, etc.

I know it sounds hard to believe, but if you're willing to bite the bullet that "the center of the universe" has no physical meaning, then earth can't be not the center of the universe any more than it can be.

To be honest, I have no idea what you are talking about.

Certainly, there is merit in practical calculations when we are all this close to the ground where it all seems either flat or at least geo-centric.

But... the movements of the other planets in our solar system were really strange to model in geo-centric models. In short, each of the other planets should rotate around an imaginary axis to compensate for their changing positions in the sky.

Of course, all this is talk about in the context of our solar system. As for us being the center of the universe, well, the same argument holds for any other point in the universe. So, I think it's less likely than me winning the lottery in the next five minutes :)

In the XVII century, the alternative to heliocentrism was Tycho Brahe’s model: Earth at the centre, the Sun and Moon and the stars revolving around it, and the other planets revolving around the Sun. It was basically equivalent to the heliocentric model with a different coordinate system.

It’s important to understand that astronomers chose it because it really seemed to provide a better explanation given the knowledge and technology at the time.

Tycho Brahe himself noted that his model could be disproved by observing the stellar parallax effect as the Earth orbits the Sun (if the Earth does move, then the stars would look slightly different throughout the year). This is a real effect, but so small that it couldn’t be observed until the XIX century.

There was even more to it. Cosmographers of the time were willing to consider the possibility that the stars were very far away, far enough to make parallax changes undetectable. The main stumbling point was that they assumed the stars would be similar in size to our sun, but based on naked-eye and telescopic measurements of the diameter of the “disk” of the stars (many taken by Brahe and Galileo themselves), any solution that explained the parallax effect would have resulted in enormous stars, and this they couldn’t accept. Eventually the measurements turned out to be an optical artifact.

I read an entire book on this subject, published by a Catholic press. There seems to be an active interest in the Catholic science establishment in rehabilitating some of Galileo’s critics.

> I know it sounds hard to believe, but if you're willing to bite the bullet that "the center of the universe" has no physical meaning, then earth can't be not the center of the universe any more than it can be.

I disagree.

The sentence «"the center of the universe" has no physical meaning» requires that Earth can't be at the center of the universe, because there isn't a center for it to be at.

You're still allowed any or many arbitrary zero-points, but that's only the center of a number line, nothing else.

It's basically a semantic issue but I don't think the negation of an undefined proposition is true, I think it is undefined. (Thankfully the universe does not run in JavaScript, where !undefined is true.)

That I agree with.

But, Earth.x = 42 (in some arbitrary coordinate space), if I understand correctly there isn't a sub-light coordinate space in this universe where Earth.x = undefined.

Positions are defined, but they're different in every coordinate system, which makes "the center of the universe," by itself, undefined.

That's not the reason why the centre of the universe is undefined.

By analogy, while spherical coordinates are arbitrary, latitude is defined. Arbitrary, but defined.

But the centre of the Earth has an undefined latitude, and a topological subspace consisting of just the surface of the Earth can't hand-wave past that by pointing out that's just a coordinate singularity that can be safely ignored — there isn't a center of the Earth anywhere in that subspace. If the universe is flat and finite (looping), this problem still exists.

And if the universe is unbounded (infinite), that has a different problem because you can't properly define a median of an infinite set[0], so no center exists.

If it just stops suddenly after a certain amount of space, then we get to have a center, but there's no sign of that.

[0] I think. Infinity is easy to get messed up with.

> That's not the reason why the centre of the universe is undefined.

Be patient. It hasn't been evaluated just yet.

We may not be able to observed it, and maybe can’t. Just like time slowing down would be imperceptible to the person on the spaceship nearing light speed. It takes the mathematics

Or if I’m lucky enough to have the time to watch the moon move slowly, it feels natural to my senses to say it’s moving across the sky. The moon feels like it’s moving around me. But I can stretch my brain and imagine the reality.

Sometimes math arrives first. We have the new maths (or an problem in current math), and that points to some possibility. Because it’s not observable, ignoring our senses is a requirement to develop that in the model and measurements and experiments. Eventually we are able to observe it.

I’m not familiar with history of astronomy. Would it be the case where the observations that lead to heliocentric thought we nuanced and had to build on more obvious perceptions that things aren’t adding up? Was the wobble of Venus part of that?

And you’re right, old models are useful and remain relevant a lot! The model of time moving linearly will likely always be the most useful model for navigating our daily choices (if we have any at all!)

I disagree, I think the comparison is pretty reasonable.

Your entire experience of the world is defined and limited by the fact that your brain "only processes information in one direction of time" (for lack of better wording). Your personal experience does not necessarily map correctly to the real world. The same is true for both examples.

It's not just a matter of our subjective experience of time, it's a matter of the laws of thermodynamics and entropy. Time moves in one direction is another way of saying entropy always increases. If time could move in the opposite direction, then entropy decreases which breaks our understanding of physics.

It's really interesting to think about how we struggle to express the idea of the future having a causal impact on the past. I reckon this is because our language and our understanding of time are limited.

Our brains like to process events in a linear sequence, from past to present to future, but this view of time might not fully capture how everything in the universe is interconnected. It's possible that our language just can't handle these complex concepts.

So, I don't think anything mentioned in this thread contradicts the idea that "time always moves in one direction" and "entropy always increases".

Right. "Time only moves in one direction" is not saying much more than "our consciousness experience time moving in one direction". The very idea that time "moves" is entirely related to our vantage point. If our perception were not bound to time, then the nature of cause and effect might look completely different.

I don't think the idea that "the future can influence the past" is the same thing as saying that entropy decreases or that time can move in the opposite direction. I think these are different concerns

The "arrow of time" conception of entropy: 1) does not work locally and only works at large enough scales, and; 2) is essentially isomorphic to the concept of time.

So no, it's not at all incompatible with retro-causality. When you think about retro-causality, the idea that time "moves" is completely superfluous. Time is probably not even a real thing.

The direction of causality should also be reversed from what I can tell. Instead of a bullet slowing down as it hits air molecules and pushes them out of the way, the air molecules push on the bullet because the bullet will be sucked into the barrel in the future.

More on topic, I think our existing theories of reality tell us that the future probably affects the past, or at very least, is predetermined. If you know the solution to a differential equation, you know the state at any point in time. There's no going off the rails, so to speak. And if the system is constrained in any dimension (i.e. it's nonholonomic) then the state at any given moment relies on the full trajectory up to that point, as opposed to just the previous state. But you can flip that on its head and say that the future state determines the present trajectory. E.g. to turn a bicycle left, you have to first turn right.

but what about reverse falling cartridge? Will spacetime around Earth change from "hole" to "hill"?

That's not going to be necessary.

I think it's the same thing. The future energy state of the cartridge is that it's in the chamber, so it gets sucked up. It's problematic though, because the direction of gravity doesn't change.

Just commented about interpreting the Probability Law as sort of "Inverted 2nd. Law of Thermodynamics".

I'll expand here how if the arrow of time actually doesn't exist, the future could change the past without breaking our - current - understanding of physics (tragiclly because we will probably have maybe hundred of years till we change our minds about what are the properties of the universe).

In a range or probabilities of one event, one of the probabilities will always be the one is going to actually happen. Closer to the event to occur the most certain you can be about which one of those, could be the one that will happen.

Here's the catch, you have to change your mind a bit, in our current understanding of physics, the information of the future event which has not happen yet, already exists here in the past for that event.

Now, if you know - and you know - the outcome of an event, you most certainly will be able to choose if you go along that path, or you choose to change the future event to something else. Whoalá, the future changed the past.

Brains of earth continously do this, every second of our entire lives, animal brains do this too, almost all life on Earth has some neurological, physiological, chemical predictive mechanism in place.

An example, you're about to walk across a street, you see a car coming, now your brain "predicts" you'll be hit by that car if you just keep walking, you stop walking to avoid certain death, done, the future changed the past. The information - really close to 100% of probability of death - extracted by the brain from the sheer reality of the universe, allowed you to survive.

And no current understanding of physics got harmed anywhere along the way of the future changing the past.

Yep. Someone else already pointed out the well known counterargument to symmetry below regarding thermodynamics. You typically don't see scrambled eggs become whole again. I think that's pretty hard evidence to overcome.

Granted, I'm not a physicist and I'm sure any physicist working on this totally understands that. Just wanted to point it out.

Scrambled eggs can become whole again by being consumed by insects, who are then consumed by chickens, who then lay eggs.

The biological processes enabling that sequence can be said to have negative entropy.

Negative entropy (also called negentropy) isn't really a well-defined concept. Instead, better to say that biological processes harvest free energy to maintain order in the face of increasing entropy.

If the direction of time is reversed, the eggs become whole again, but your memory of them once being scrambled is reversed, too, so you don't notice anything unusual.

(It's like a rollback of database transaction, where not only the database state, but also the state of everything, including your brain, is getting rolled back)

That would suggest a kind of "super timeline" I'd imagine.

But is there any evidence of that? Or is it just a thought experiment? I need to read more of the article, but appreciate you giving me some food for thought.

It's a thought experiment, of course. There cannot be any evidence one way or the other, by definition. Any potential evidence is rolled back, too. But then, why are we so sure our current beliefs WRT the arrow ot time are true?

Though there's no hard evidence, but if you think, for example, about the efficiency of evolution - it would be much easier to explain if we assume that the unlimited number of iterations is performed. (This is not the only possible explanation, of course- but this one is overlooked IMO)

I would say that compared with the strange ideas like "multiverse", this one is rather benign :-)

If the future could affect the past, it suggest that then if time reversed, you would notice something unusual right? Kind of like suggesting there is a side effect in your function (consciousness). Kind of like how today, past events can influence the future like we act differently from learning from mistakes.

So the conscious experience of the person at each time would be exactly the same as our experience. They would feel as if they were moving forward in time.

The argument is that thermodynamics is simply a statistical phenomenon. Scrambled eggs are due to proteins denaturing (folding in a random way).

Scrambled eggs do actually unscramble spontaneously if you zoom in far enough. The issue is that the rate of scrambling is much higher than the rate of unscrambling so on the whole, you get scrambled eggs.

The amazing thing is that all chemical processes are actually reversible given enough energy and finesse.

Assuming that time "moves" kinda is

Nothing actually moves according to Zeno's paradox.

Zeno's paradox assumes space is infinitely divisible.

they didn't understand limits

You don't understand physics. Or logic.

Nature doesn't have to obey any particular set of axiom you adopt.

Can you make your point without a personal slight?

can you profe to me that the physical space between everything isn’t?

Planck length.

Yes I know what was meant and that’s my point. That is not a physical proof but a mathematical abstraction.

The real number line is infinitely divisible, but you can still move a point along it.

It's comparable to GPT4 being shocked that we can read backwards!

Here's the analogy, per Sean Carroll [1]:

- There seems to be a special direction "down", where things fall by default, because we live in the vicinity of an influential object in space, called Earth

- There seems to be a special direction "forward in time", where things happen by default, because we live in the vicinity of an influential event in time, called Big Bang

If we had stuck to the local Earth context and geocentrism, the objectivity of the "down" direction would remain unquestioned. It's when we started modeling other things outside of Earth, it became clear there's no objective "down" direction, just a more general concept of Gravity.

Carroll's argument is that it's the Big Bang, an extremely low-entropy configuration of the universe, that gives rise to the 2nd Law of Thermodynamics and the resulting emergence of an arrow of time in the forward direction. It's purely a statistical phenomenon at larger scales, and attributable to being "next to an influential event", according to him.

[1] https://www.youtube.com/watch?v=AZsmyTE3j9o

It's difficult to see how such a hypothesis could be tested either experimentally or observationally. Sounds more like metaphysics?

Stars shine until they run out of fuel, and the age of a star - the status of its fuel, the buildup of fusion products - happens as time passes. Life on planets taps into the flow of sunlight from the star (and/or the flow of heat and chemical energy from the a hot planetary core) to generate complex structures in defiance of the regular direction of entropy (not violating conservation of energy, though). So... life reverses the arrow of time?

Well, of course not :) Entropy as direction of time just means that the chaos on the whole increases. So, to create an ordered structure, like a cell organism, the by-product is more chaos around it.

To add, life just speeds up the chaos by orders of magnitude, it's a perfect entropy catalyst.

I’d be shocked if that were the case, even only considering the Earth. The oceans and the atmosphere are full of entropy. So is the liquid outer core. And even if the mantle is not quite liquid, and even if the crust is mostly solid, these are huge in terms of volume and mass, much larger than the sliver of dirt we inhabit on top of them. So yeah, I really doubt we (collectively, all human beings) are changing the Earth’s entropy in any meaningful way.

Life reduces local entropy.

At the expense of increased global entropy, which I suppose is GPs point.

"there is 10 million times more entropy in that radiation [cosmic microwave radiation] than there is in all of the mass of the universe"

https://news.berkeley.edu/2016/09/20/new-book-links-flow-of-...

But then, this is just entropy from a one-off event long ago. Meanwhile, life is an entropy producing reaction with a strong exponential factor.

To butcher an insightful quote by (IIRC) Hamming, any positive slope will eventually make up for y-intercept of a constant function.

It underlines the idea that the entropy-time connection is pretty shaky though.

I think that the real question is whether the death of the universe by cool down will happen before the arrow of time is reversed. To me it seems more like it will just slow down and then finally stop.

Or if there ever is a "big crunch" where all black holes crunch together to a critical mass, would there be another big bang and time then run backwards?

The hypothesis I have encountered is that time would reverse when the expansion of the universe peaked and started to collapse back in on itself. The next big bang would start another run of our universe. I'm guessing the randomness in quantum fluctuations would allow this next run to evolve somewhat differently from the one we are experiencing.

I think that one thing to keep in mind is that we are only capable of observing the passage of time along one vector because our perception relies upon entropic biological processes.

We cannot observe in any subset of possible universes where entropy is not present or is working backwards-Ergo those possibilities are wholly out of our direct perception.

That does not mean that causality cannot run in reverse, however, only that we cannot interact with those mechanisms in a way that would preclude our existence or observation.

But could we observe the effects? Can there be particles which have mass and therefore exhibit gravitation but which are subject to reverse entropy? We would observe these for example as an unexplainable increase in gravitational pull on observable matter without an observable source of that gravitation and without a preceding cause.

Are photons themselves stratling this entropic boundary since they travel at the speed of light and within their own reference frame are not subject to the passage of time?

Biology has nothing to do with it. We can't construct any manner of machine that measures time going in the other direction.

Maybe all that quantum nonsense we can't explain is due to some type of time travel we don't comprehend.

If only we had Tony Stark to help build some sort of a “quantum GPS”.

Wouldn't questioning those pre-existing notions be the first step towards constructing such a machine? It sounds silly to dismiss the idea time could go backwards because we don't have any machines that work that way, since that typically how all ideas work before we implement them.

> It's difficult to see how such a hypothesis could be tested either experimentally or observationally. Sounds more like metaphysics?

Sure, but some claims which cannot be tested experimentally or observationally are nonetheless important. For example, the claim “it’s important that scientific hypotheses be tested experimentally or observationally.”

While I agree that not everything in science can be tested experimentally or observationally, arguably this one can:

Models created using both empirical experimentation and logical reasoning match reality much better than those based on "pure logics" (if that even is possible).

Alain Aspect tested it with his delayed choice quantum eraser, didnt he ? (https://en.m.wikipedia.org/wiki/Aspect%27s_experiment)

At least in France we take as fait accompli that causality is non trivial and that objects are non local at best: either you can consider objects as one despite immense distance between them, or you accept information passed between them in reverse time. Both are hard to swallow.

No, he didn’t. The “delayed choice quantum eraser” is something else - and it’s not about the flow of time either.

> Life on planets taps into the flow of sunlight from the star (and/or the flow of heat and chemical energy from the a hot planetary core) to generate complex structures in defiance of the regular direction of entropy

It doesn't defy the direction of entropy. Frankly, I'm not sure why you have that notion? Entropy is a measure of system's state of equilibrium. Moving energy from a concentrated source, and distributing it more equally (across life forms and other complex structures), is following the direction of entropy, as is it makes energy more equalized, in contrast to the former state where energy levels are more unequal between highly concentrated areas (like stars, the Big Bang), and areas with less energy.

Entropy only increases on average. You can decrease it locally, for example, making steel from iron ore. You generate heat, so you still get a net increase, but you could easily redefine your boundary to only include the local decrease in entropy (the steel from ore).

Yes, but like you said, that requires re-drawing your boundaries. It doesn't really defy the direction of entropy, it only appears that way from having changed scope.

"Sounds more like metaphysics?"

The regular arrow of time from the human perspective, "leaks" changes into the future. The future is constantly being changed by the past.

You can measure those changes by many ways, the 2nd. law of thermodynamics is everywhere just to make sure you see this happening across everything.

So, probably there are other non-discovered underlying mechanisms in the reality that are already signaling changes from the future "leaking" into the past, changing the past right infront of us, without us noticing it.

A probably omnipresent mechanism for observing the future changing the past, valid in the whole cone of light visible to us, is the probability law.

If you have 10 millions of possible events in a probability, one of them is the exact thing it will happen in the future, hence the information of what happens in the future is right here, existing in the past.

Yeah, you can say how would the nature could use this information without powerful processors predicting branches trillions of times per second on Earth right now?

Well, the brain is a pattern predictor, quite several parts of the brain are firmly attached to the physics of the universe, biochemically but what if the pattern prediction mechanisms in the brain are actually an adaptation of the evolution, just like wings to fly, but with those mechanisms the brain uses probability to "see" information from the future, and here in the "present", it changes the past (from the perspective of the future created originally from the past), if the brain "chooses now" to do something different that what originally created the future it "saw" by analizing patterns, essentially evaluating probabilities.

So the Probability Law would be a kind of Inverted 2nd. Law of Thermodynamics.

It would work perfectly as law of the universe: from the future to the past, the revered time of arrow, one single event created "a" future, but from the regular arrow of time, there would a range of probable future outcomes which you cannot precisely say it has "1" (100%) probability of ocurring, right to exact moment till the future becomes the present.

And it was right there all the time, something obvious infront of everybody in the world, like electricity (which was suspected by many across thousands of years, but just "discovered" recently).

https://en.wikipedia.org/wiki/Law_of_total_probability

I don't think Carroll can take credit for the idea of the arrow of time being emergent from a local entropy initial state.

Roger Penrose proposed that as far as I know, when Carroll was probably a high schooler.

who's taking "credit"

Roger Penrose proposed that as far as I know, when Carroll was probably a high schooler.

No. At least as early as Arthur Eddington when Penrose was a twinkle in his dad's eye.

Thanks didn't know he'd made that argument although I knew he made the connection between entropy increasing and arrow of time.

Explaining an idea is not equivalent to taking credit for it.

> Carroll's argument

This assigns credit to Carroll.

It merely says that Carrol argued. The idea within the argument was no means assigned to her but used to make/support it.

Sean Carroll is a man, and look up the possessive apostrophe while you're at it!

This idea of time's relation to entropy is pretty iffy. I recommend this book https://news.berkeley.edu/2016/09/20/new-book-links-flow-of-....

Right, entropy can decrease, just with low probability, which you can calculate using the Fluctuation Theorem: https://en.wikipedia.org/wiki/Fluctuation_theorem

Perhaps given infinite time, we will randomly get back to a low entropy state infinite times, but I don't know enough about the math to say for sure.

You can, but that inevitably leads to far more Boltzman brains than things like the universe, and that's disastrous because then you should expect to be a Boltzman brain yourself, but they're configured randomly so if you are a Boltzman brain you can't trust any belief you have about reality including the maths that says you should be a Boltzman brain.

It's basically a softer version of Russell's paradox but for cognition and reality.

Carroll did a great solo podcast about this last year: https://www.youtube.com/watch?v=B40PRvLtiec

Hard to summarize, but it's well worth anyone interested in this topic. There's a good bit where he ties the sleeping beauty thought experiment with Boltzmann Brains and consciousness; it blew my mind trying to understand the whole thing.

Infinite time is too much of a “get out from jail” card, because during infinite time anything and everything will happen by definition

I don't have a problem with "time" meaning "away from the local Big Bang". But that does not imply that future causes the past.

Just like noticing that "down" actually means "towards the center of the local planet" did not make water suddenly flow uphill.

The comparison is bad all around. Geocentrism actually had decent reasoning and was not a superstition. It's just we couldn't see the parallax with then-current instruments. As soon as instruments allowed, humanity changed rather quickly.

Time moving in one direction actually has decent reasoning and is not a superstition. It's just we can't detect time moving backwards with now-current instruments. As soon as instruments allow, humanity will change rather quickly.

The problem with the comparison is what it's used to imply. The popular understanding* is that scientists believed in religious dogma, and that led them to 'unscientific' geocentrism and believing that time has only one direction. It's a backhanded accusation of superstition, and that's unfair towards both current scientists and past scientists.

(On a personal note, I'm actually sympathetic to the article's retrocasual proposition. I suspect reality is non-local and TSVF etc. naturally tend towards non-locality.)

* This is Vice, of course they use the popular understanding and not something more sophisticated.

It seems to me that the popular understanding is influenced by grossly misleading 20th century anti-religious propaganda. The geocentric model is not something the Catholic Church plucked out of the bible; they got it from Ptolemy and other 'heathen' classical thinkers, whom the Catholic Church considered meritorious despite not being Christians. Sure, they then found some biblical citations to back themselves up in this, but the idea was never their own in the first place.

We've always been able to detect that some celestial objects appear to move backwards at times.

> Slow down. Assuming that time moves in one direction is not comparable to geocentrism.

Why not?

The "arrow of time" almost always requires thermodynamic arguments. And that requires a concentration of "low entropy" to move toward "high entropy". Which, by definition, are "boundary conditions" and not a fundamental part of your physical rules.

If, for example, your universe is entropically uniform, is there an "arrow of time"? And, even if there were, could you detect it?

However, I would like to point out that it's not like we haven't had this kind of issue before. The Bohr-Einstein debates were a good example. Einstein favored a "fields" interpretation of quantum mechanics. Unfortunately, Einstein's interpretation predicted that atomic states wouldn't decay, and that was clearly, obviously wrong, and Bohr very much hammered on that.

Except that Einstein wasn't "clearly, obviously wrong." As you increasingly isolate excited atoms, their atomic states take longer and longer to decay. The problem was that the experiments of the day couldn't create these kinds of singular quantum state systems--they were stuck with systems that were contaminated with lots of thermodynamic interactions.

We may be seeing something similar here. We are just starting to be able to put together the experiments that can probe things like Bell's Inequality. As we isolate these systems, we may find that the systems were contaminated with statistical time and that we get different results when we can isolate them.

> If, for example, your universe is entropically uniform, is there an "arrow of time"? And, even if there were, could you detect it?

What does that even mean? If your universe is entropically uniform there is no “you”.

>If, for example, your universe is entropically uniform, is there an "arrow of time"?

Nope, and there's a really great 'physics slam' about this, sadly only in German but auto-translate seems fine. https://youtu.be/z64PJwXy--8?t=519

> If, for example, your universe is entropically uniform, is there an "arrow of time"? No. For a system at thermodynamics equilibrium entropy is constant, neither increasing nor decreasing. So there is no arrow of time, no sense in which one direction is "the future" and the other "the past".

If a universe were entropically uniform, wouldn't the arrow of time definitely be negative? Wouldn't any random evolution result in a lessening of entropy by definition?

> If, for example, your universe is entropically uniform, is there an "arrow of time"? And, even if there were, could you detect it?

Would we have fluctuations in that state? In which directions they would... Progress?

Isn't what you describe an anomaly like black hole or division by zero, where we cannot understand what actually happens because normal laws break because they are unsolvable with current models?

Geocentrism seemed reasonable until it didn't.

If time is a true dimension rather than just something we model as a dimension, it's not unreasonable to think that outcomes in the present could be influenced by constraints that exist in the future - if the "universe" function must be valid according to some constraints at all points in the time dimension, "past" states that lead to invalid future states will never occur.

The idea of invalid universe states is of course purely fun conjecture, but this same concept also maps to probable vs improbable universe states as well. If a future state is improbable (in the sense of a Bayesian prior according to some underlying distribution of energy in the universe) that might cause the universe to evolve in a way that seems improbable at the moment by moment level, but is actually the most probable sequence of events when integrated over the entire duration of the universe.

Time could move backwards if we lived in a time symmetric universe. We don't. Maybe if you flipped the charge and handedness of the entire universe you could also reverse time, but that's yet to be tested.

https://youtu.be/L2idut9tkeQ

How so?

The idea doesn't seem so different from matter being the default (vs. antimatter), relative speeds much closer to zero than to the speed of light being what's commonly observable etc.

I think the actual assumption is that we are currently seeing just one direction of the arrow of time, but if there is no arrow of time, maybe we are already seeing the future and not realizing it is the future.

I commented further in this line of though in another comments, about a probable (ironically), "Inverted 2nd. Law of Thermodynamics" of sorts, which it would be basically just the Law of Probability, interpreted from the point of view of not having an actual arrow of time and the fact that we have - all the time, again ironically - the information of what happens in the future (the one probability in the range which ends being the right one, actually ocurring).

Yeah, I know it would be another Law, and the universe would upside down once again for us the poor meatbags, but we were already in this position several times, discovering the electricity, quantum mechanics, relativiy, you name it.

Human instincts only apply to the systems that they're "evolved" to handle (or the systems we can readily observe and learn from).

Think about big systems. The moon is a ginormous rock that's so big it is visible from thousands of km away, but it just hangs in the sky because it's moving so fast it can cheat gravity, but we can barely even see it move. Or think about how a star can somehow explode because it starts running out of fuel (and our sun is just yellow hot - you can do that with a blow torch, but it's powered by a nuclear explosion - I guess it's got quite a bit of surface area?). And little things are even weirder, consider how fast the proteins in your cells bounce around. Then there's quantum - our gut intuition is so out of its comfort zone it's basically meaningless.

Right, something along the lines of Donald Hoffman's The Case Against Reality

I used to work at camp. You didn’t need to tell kids about fire; they could figure it out. Don’t touch the fire. Flashlights were too complicated. It’s night, a kid turns on their flashlight, points it in their eyes, says “ow” and can’t see where they’re walking until their eyes readjust. Flashlights are beyond our instinctual understanding of how the world works.

Maybe this is just because the kids had prior experience with fire (touch it = ouch), but no experience with flashlights?

Yes. If we learned something about fire, it's to teach the youngest ones to stay away from it. Nothing more. An unattended and untaught kid will try it, at least because it's nothing like they've seen before.

it's funny you mention flashlights. NO matter how many times I tell people not to point their flashlight at people's eyes, it happens (by accident) over and over. It bothers me a lot because I am very good at getting my eyes dark-adapted and as soon as somebody flashes me, I lose about 10 minutes of dark vision.

The sun being classified as a yellow dwarf does not mean it's "only yellow hot". You can observe that by going outdoors and holding up a white piece of paper and noting it is not yellow in sunlight.

powered by a nuclear explosion

Not quite accurate. The nuclear fusion going on inside the sun's core is not an explosion. In a nuclear explosion, a significant fraction of the fuel in a given area is consumed in an instant. The sun's core on the other hand only fuses its fuel extremely slowly. Pound for pound, the sun's core generates less heat energy than mammalian muscle tissue. It's just that there's so much of it that the heat energy is extremely well insulated.

The sun is the color it is because its surface is 5500 Kelvin, which we have defined as white. The sun is cooler than most visible stars, so it can be called yellow by comparison.

The sun appears slightly yellow because the atmosphere scatters blue light more than the rest. The result is the sky looks blue, the sun is slightly yellowish, and the cumulative light (both directly from the sun and diffuse light from the sky) is white. Outside the atmosphere, our sun appears proper white.

The sun is cooler than most visible stars, so it can be called yellow by comparison.

Incorrect. The out of atmosphere color temperature of Sol is ~5900K. The average color temperature of the Milky Way is 4700-5000K.

https://www.news.pitt.edu/milkywaycolor

Perhaps our gut is right and our conceptual models are wrong

> In addition to potentially rescuing concepts like locality and realism, retrocausal models also open avenues of exploring a “time-symmetric” view of our universe, in which the laws of physics are the same regardless of whether time runs forward or backward.

Usually the fundamental laws are regarded as time symmetric already.

What does this mean: > Instead, retrocausal models suggest that there is a mechanism that allows circumstances in the future to correlate with past states.

Surely future states inevitably correlate with past states?

Perhaps it all makes sense but that article doesn't make a compelling case.

We don’t have a time symmetric model of wave function collapse, to my knowledge. If I’m wrong I’d be super curious to read about it

Wouldn't many worlds be time symmetric?

Yes, but it’s not a model of wave function collapse. Its very premise is that there is no wave function collapse.

Measurements are adjoint to state preparation. Depending on what you measured you can prepare a special state at that time to make the system time reversal symmetric.

Just reverse time in the evolution operator.

We don't have a model of wave function collapse at all, iirc.

Not an expert in this area at all but there have been some experimental findings in the last five or so years that suggest the possibility of retrocausality.

This is just one example I found but I think there might be another experiment from a few years ago that was getting some attention at the time (although I might be confusing it with a theory paper):

https://www.nature.com/articles/s41598-023-29970-6

There are probably better overview articles on retrocausality.

https://www.newscientist.com/article/mg23731652-800-quantum-...

https://aeon.co/essays/can-retrocausality-solve-the-puzzle-o...

https://phys.org/news/2017-07-physicists-retrocausal-quantum...

I'd have to read through all these more thoroughly but I wonder if there's some "time locality" property in these models?

>Surely future states inevitably correlate with past states?

He means to correlate through effects going the future -> past direction...

Yes, of course. But that is not how correlation is usually expressed. And it also doesn't explain what it means. It just sounds like philosophers doing some hand waving.

What can it mean to have an effect propagating into the past? Surely our usual definition of time is simply a series of events. If so then it always points in one direction for the entity sitting at the leading edge, the current event is always succeeded by the next event.

All I have to go on is the article, perhaps the source material makes more sense.

> Usually the fundamental laws are regarded as time symmetric already.

Well, in addition to time reversal, you also have to mirror the universe and replace all particles with their anti-particles.

As a non-physicist I'm not sure I'm interpreting this correctly. Does this essentially mean that all states in time already exist and our consciousness is just traversing this 4D space in one direction on the time axis?

If so, does that mean that the big bang could actually be the end of the universe and we're just experiencing time in "reverse" toward an initial starting state that we perceive as the future?

The block universe: https://plus.maths.org/content/what-block-time

Is it the same thing as the holographic universe theory that was in vogue a couple of decades ago?

https://i.pinimg.com/originals/27/d7/8c/27d78c9c3ee93c13eda4...

No. The block universe is that 3+1D spacetime "exists all at once". We just happen to experience travelling through it in one way.

Holographic universe is that the physics and information in a 3+1D space time could be encoded into a 2+1D universe (with it's own physics).

Ah, Discover had an issue about that as well

https://www.discovermagazine.com/the-sciences/from-here-to-e...

https://i.ebayimg.com/images/g/xH8AAOSwryZi3Ef0/s-l1600.jpg

I like this concept. Is there any sci-fi based on this premise?

Reminds me of the Tralfamadorians from Slaughterhouse-Five. They are able to see in four dimensions so humans appear as fetuses at one end of the four-dimensional person and dying at the other end.

https://en.wikipedia.org/wiki/Tralfamadore#Slaughterhouse-Fi...

Interesting concept. I wonder if it's compared with spatial 3D space, then how large would the 4th dimension of time be if it were to fit the timeline of a human lifespan

A natural interpretation leads to time being very large and us moving very very fast through it.

It's convenient to model our movement through space-time as occurring at the speed of light. Thus, the faster we move in space, the slower we move in time all the while the length of our space-time velocity vector is invariably c. We can then imagine 1 second of time being interchangeable with 299,792,458m.

...which means that a Tralfamadorian would see an average human as a 6*10^17 meters long snake.

Greg Egan - A Clockwork Rocket (book 1 of the Orthogonal trilogoy, all three of which I recommend)

Aliens in the movie Arrival perceive time in circular fashion, basically live in future and past.

And the movie is based on Ted Chiang’s novella, "Story of Your Life"

Just saying, this is a pretty big spoiler.

Not sci-fi, but the block universe is central to Alan Moore's Jerusalem.

Surely reminds me of Harry Potter and the Prisoner of Azkaban, where Harry is saved by himself as he at some point in the future travels back in time to save himself.

Bill and Ted's Excellent Adventure, but yeah.

The Nolan film "Tenet" is based entirely around the idea of reversible causality.

The 'Dirac Beep' in this short novella (1973):

https://en.wikipedia.org/wiki/The_Quincunx_of_Time

Also, the concept of causality itself is a kind of underlying theme in Hannu Rajaniemi's "The Causal Angel" (2014) (3rd of a series).

While most laws of physics may be time symmetric, the laws of thermodynamics are not - wherever there is a gradient in entropy.

In very informal terms, anywhere where there is very low entropy (higher order), any direction away from that will likely (to the point of certainty) be in a direction of higher entropy (lower order).

For instance, if you have a jar of red & blue marble, with high order (such as perfect alternating layers of red vs blue marbles) then any disturbances (such as shaking the jar, reaching in and moving a handful, …) will almost certainly reduce order.

And no practical amount of shaking the jar will ever return the marbles to a high order state again.

Even though any close up video of the marbles being jostled will reveal the same physical properties and behavior for the marbles, whether played forward or backward.

So at the individual marble level, laws are symmetric.

But at the jar of marbles level, one direction of time looks very different than the other.

We, and the particles that make us, and our environment, are the marbles whose configuration is more disordered the further in time we get from the Big Bang.

So we perceive the time direction away from the Big Bang as the future, toward the Big Bang as the past.

And the statistical “force” of increasing entropy provides the useful energy we use to survive, learn, create useful islands of order, in the greater sea of increasing disorder.

> And no practical amount of shaking the jar will ever return the marbles to a high order state again.

This can't be true. Take the case where there's only 2 marbles, it's likely that at some point that shaking them will return them to the original state. For higher numbers of marbles the probability becomes lower and lower, but is never 0.

With enough marbles, the discrete distribution behaves like a continuous distribution. The point probability of a continuous distribution is infinitely improbable -- in other words it is 0.

(0.00..0..1 = 0 just as 0.99 repeating equals 1)

> infinitely improbable -- in other words it is 0

This sounds like a rather bold statement to make, as long as we're already speaking so metaphysically.

The statement is mathematically correct [0].

[0] https://stats.stackexchange.com/questions/142730/px-x-0-when...

We're talking about physics, not mathematics. We don't have the luxury of hand-waving away fundamental questions about the nature of the continuum.

See: https://en.wikipedia.org/wiki/Continuum_hypothesis

Please elaborate.

I'm neither a mathematician nor a physicist, so I'm not nearly informed enough to elaborate on the subject properly, but I would note that the axiom of choice is not proven, and while you can mathematically divide a continuum into infinitesimally small sets, you cannot do the same to physical matter. From my understanding, many of the contradictions between classical and quantum physics arise at this boundary between the discrete and the continuous, where classical physics generally assumes continuity while quantum physics is constructed around discrete quantization mostly independent of time.

Again, I'm not a physicist, but I think it's telling that the validity of continuum mechanics [0] depends on a model and multiple assumptions. I have no trouble agreeing with your original statement, "with enough marbles, the discrete distribution behaves like a continuous distribution," when speaking mathematically, but mathematics by its nature is an idealized model of the world - I'm not willing to accept that it's objectively representative of physical reality. The discussion we're having here is one of metaphysics, so it feels a bit like the height of hubris to use mathematics as the tool for describing objective reality, because metaphysically, we cannot say that mathematics is anything other than a tool we've constructed for approximating the model of the world as we understand it. Considering the subject of this post is about retrocausality, we're already throwing out some pretty wild ideas, so I think it's a bit hubristic to dismiss them by citing a branch of mathematics that assumes the existence of countably infinite sets [1].

[0] https://en.wikipedia.org/wiki/Continuum_mechanics#Validity

[1] https://en.wikipedia.org/wiki/Constructivism_(philosophy_of_...

This whole thread hinges on your not giving credence to the word "practically" , as in "approximately". No countably infinity needed, and Continuum Hypothesis isn't relevant at all in any way, as it is aboit uncountable infinity. Until you explain what you are trying to say, you aren't saying anything meaningful. The one showing hubris here is you, tossing around technical terms don't admit you don't understand.

> The one showing hubris here is you, tossing around technical terms don't admit you don't understand.

Hence the disclaimer. I just think this stuff is fascinating. If you're interested, this is the article that originally got me thinking about these ideas as they relate to the flow of time: "Does Time Really Flow? New Clues Come From a Century-Old Approach to Math" [0]. It's effectively an appeal to intuitionist mathematics and a rejection of constructivism, where - simplified - every particle since the big bang can be assigned some "number" that describes its position on its world line, with a precision that is finite, but always increasing - and it's this increase in precision from which emerges the "flow" of time. If you ctrl+f the article for "continuum," you'll see some better constructed arguments for what I'm trying to argue, e.g.:

> Moreover, the continuum can’t be cleanly divided into two parts consisting of all numbers less than ½ and all those greater than or equal to ½. “If you try to cut the continuum in half, this number x is going to stick to the knife, and it won’t be on the left or on the right,” said Posy. “The continuum is viscous; it’s sticky.”

The impression I'm left with is that the difference between constructivist vs. intuitionist mathematics (which rejects the law of the excluded middle) has some parallels to the difference between eternalism (there is a past, present and future) vs. presentism (there is only the present).

As a layman, I just can't help but notice the same patterns come up again and again when looking at unresolved problems between classical and quantum mechanics, namely those that lie at the boundary between the continuous and discrete. FWIW, I asked ChatGPT for some unresolved mathematical problems that might relate to this, and it came up with: The Continuum Hypothesis, The Axiom of Choice, and The Riemann Hypothesis, all of which it admitted are possibly impossible to prove because they're effectively unfalsifiable. (I also showed it this entire thread, and it agreed with your critique of my arguments, but also that every argument in the thread is unfalsifiable - and then it pointed me to the Boltzmann Brain paradox).

[0] https://www.quantamagazine.org/does-time-really-flow-new-clu...

Indeed, the original claim treats mathematics as a modeling tool, not philosophy. Nevertheless, it is my belief that untestable hypotheses about True Reality (should it even exist) are not debatable without causing migraines of epic proportions. There's no physics without mathematics -- as physicists say, shut up and calculate.

>We're talking about physics, not mathematics.

Mathematics still apply.

Mathematics applies insofar as it can model the subject under discussion. It's a great tool for, dare I say, 99.999999...% of practical problems. But mathematics is an imperfect model of objective reality that cannot resolve metaphysical problems like Zeno's paradoxes [0]. Any discussion of retro-causality is inherently one of the philosophy of space and time, which is the domain of metaphysics, not mathematics, so we can't necessarily apply familiar mathematical lemmas to resolve the problems it creates.

[0] https://en.wikipedia.org/wiki/Zeno%27s_paradoxes#In_modern_m...

[1] https://en.wikipedia.org/wiki/Philosophy_of_space_and_time#D...

There can't be an infinite number of marbles in a finite amount of space.

The number of possible states asymptotically approaches infinity, so we can model it as such. You can get a more "accurate" model using more math (with measure theory), but the terms will coalesce such that they are negligible.

negligible isn't zero, and time at a universe scale may be longer.

Any point is infinitely improbable when sampling with infinite precision, only because this calculation is not computable.

Even if the point probability is 0 or approaching zero very fast, some event occurs with probability 1.

The probability that life would evolve on a blue planet that its anthropomorphic inhabitants will come to call Gaia or Earth, has as a star Sol, in this corner of the Milky Way, in this particular local group and so on is zero even if we limit ourselves to just the observable universe.

At the same time the probability that life will exist at some planet at some solar system at some galaxy at some local group and so on, is practically 1.

That is to say, depending on how you categorise and count said marbles, the reordering may occur.

While any individual marble will not be at its place with P=1. You can still end up in a situation where the marbles are ordered in layers.

The whole thing regarding entropy is concerned with a closed system. You can very much exchange energy to decrease entropy, but said exchange is a) leaky, and b) implies that the system is not isolated.

A probability of zero does not mean that the event is impossible. When we refer to probabilities we are talking about probability densities. Infinite precision is a useful modeling tool in the same way that approximations of pi are useful.

I think I was misunderstood. My comment regarding infinite precision was mostly aiming to argue that any single point has probability zero but an event still occurs.

This was then used again when mentioning earth to argue that depending on the definition of "order" here:

> And no practical amount of shaking the jar will ever return the marbles to a high order state again.

It is entirely possible to reach a state of higher order if you don't require that individual marbles don't hold the same arrangement relative to adjacent marbles, meaning that any permutation of marbles with identical color is acceptable.

This happens because the event you are asking for is a very large subset.

Define "large", at least in an estimate. Dividing two astronomically large numbers is not easily estimated. And define "entirely possible". Yes, could happen once, maybe, in the entire Universe is entirely possible. Anything is "entirely possible" because humans are not omniscient, so we have to start from Bayesian priors.

In a well defined system, a probabiltiy of zero by definition means an event is impossible.

In physics, nothing can be measured exactly, so exact events are in fact impossible. Measurements are approximate, and thus have finite extent, and thus can have nonzero probability.

This whole thread is silly, The 2nd law is about probabilities which are asymptotically 0, so small in practice that we could never do experiments to frequentist probability empirically, using "jars of marbles" with more than 100 marbles", let alone trillions of trillions of particles.

That is a great point. The laws of thermodynamics exist as a logical consequence to fundamental statistical principles. It is statistical mechanics that gives rise to entropy, not the other way around. (hence the beautifully elegant equation S = Kb*ln(Omega) where Omega is the number of microstates)

I realize that programmers are not always good scientists. Yet some claims are absurd in ways that I now believe this phenomenon necessitates rigorous study.

> Zero probability does not mean an event cannot occur! It means the probability measure gives the event (a set of outcomes) a measure zero. [0]

[0] https://stats.stackexchange.com/a/273398

you're correct. In stats/thermo class there's a commonly taught "what's the probability of all the molecules of air in a room spontaneously moving to <extremely small location>". The problem is that shoving all those molecules into a tiny location woudl increase the pressure tremendously, sending all the particles in directions that would eventually return to a uniform distribution.

IIUC my professor right the probability is non zero but is practically impossible for a large number of incompressible spheres.

> For higher numbers of marbles the probability becomes lower and lower, but is never 0.

Exactly. It doesn’t take a very large jar to make a return to an original state practically impossible. But even for two marbles, shaking them to return them to their original locations costs a fair amount of organized energy.

And that is organized chemical energy in your muscles, which you are dissipating as disorganized heat energy due to your efforts, increasing the total disorganization.

And the marbles are microscopically wearing down, shedding compounds. The jar is also wearing down. Both becoming less organized.

So even with two marbles, overall entropy continues increasing.

We can locally reverse entropy, only at the cost of actually increasing entropy in total.

- Organizing your day takes effort and uses up useful organized energy.

- Computation uses up useful organized energy.

- Your cells, maintaining their metabolism, uses up useful organized energy.

No matter what we do, entropy still increases.

That all makes sense, but why does cause and effect seem to go one way with the entropy arrow?

Because cause and effect is more understandable and controllable in one direction.

Everything we do takes advantage of the higher to lower entropy gradient.

We get relatively organized photons from the sun, a percentage get stored in wood of trees, so we can burn that for heat which can drive an engine or generate electricity, with the end result is doing some useful work.

And we don’t actually lose any energy, due to conservation of energy.

But we have now lost USABLE energy, because all our captured energy is now heat diffusely spreading out from our engine into the atmosphere where it becomes uncontrolled DISORGANIZED and therefore no longer usable.

So clear causes tend to occur in past of clear effects.

For large objects.

But again, if you watch videos of individual marbles bouncing around, forward or backward, you see just as clear chains of cause and effect in either direction.

Not sure if you appreciate this, but if you repeat the shaking experiment enough times, you will see it return to perfect order- at some exceptionally tiny probability. I'm pretty sure you are saying that but instead of "practical amount", it's easier to say it's just exceptionally unlikely.

Well lifetimes of shaking is not practical is it.

Marbles in a jar are not arranged in a neat spacial grid, but in all kinds of configurations.

The chance of recovering any near perfect starting symmetry, depending on the size of a jar, might take decades or millions, or more years.

In the meantime, all that energy being used to shake the jar is generating huge amounts of heat entropy.

So I think I understand this argument and it makes sense to me (at the moment). To me the (to paraphrase), "increasing as we move away from the big bang" stuff seems to lead right to the idea that the expansion of the universe is what we perceive as the passing of time, but I never hear any one knowledgeable say that. Is there some obvious reason that it's not that succinct?

No, the expansion of the universe isn’t the same thing as increasing disorder of particles.

It is possible that that the original expansion, inflation, and even dark energy are also driven by thermodynamics, but we just don’t know that.

I see, I was conflating the expansion with disorder. Thanks.

"And no practical amount of shaking the jar will ever return the marbles to a high order state again."

Im not saying you're wrong, but then there's Poincare's recurrence theorem. Entropy is funky. (Certainly not practical amounts anyway)

You can wish yourself well in the past. I believe this works.

I think of personal growth as a conspiracy between present me, past me, and future me. Where our motives are aligned, good things happen.

This is good! And ask for help from the future :)

sometimes I feel like I've already asked for too much from the future

Allow me to steal this bit of insight

I'm just another incarnation of you anyway, so it's not even stealing.

Past me leaves future me notes.

I often find them insightful, especially if I am reviewing them again years later.

The reverse is the more interesting part. Roko's Baslisk loves you and wants you to be happy, and wants you to create him.

You're actually the lamination of what you typically consider to be yourself, across all time periods in which you exist: a 4-dimensional spacetime worm.

Must it be "the" time axis? Might it instead be "our" time vector? Maybe there are alien civilizations right next door which we fail to recognize as life because our time vector is orthogonal to theirs. Instead they're just gamma ray bursts to us.

Several things:

– The laws of physics are essentially time-symmetric, and they have no concept of causation or of a preferred direction of time. In principle, the future causes the past as much or as little as the past causes the future. Physics effectively only says they have to be consistent with each other, as related by the laws of physics.

– The apparent directionality of time that we perceive is suspected to be tied to the entropy gradient we are on. See the “past hypothesis” for example [0].

> Does this essentially mean that all states in time already exist and our consciousness is just traversing this 4D space in one direction on the time axis?

– I would say that all moments in time are equally real, including our consciousness at any given moment. There is no actual flow or “travelling”. The flow we perceive is merely an illusion caused by the fact that we only remember the past and not the future (which again may just be a consequence of the entropy gradient we are on). This is known as the “block universe”, or as “eternalism” [1]. The opposing view that only the current moment is real, and that the future differs from the past in its “realness”, is known as “presentism”.

– Note that any notion of “travelling” through time implies that you can draw a 2D diagram of where in time you are at each point in time, or which point in time is “real” at which point in time (in the sense that a moment in time isn’t real until time reaches that moment, but after that it is real and cannot be made unreal again), thus implying two dimensions of time. That doesn’t make any sense, and thus my personal conclusion is that the “presentism” view is nonsensical.

[0] https://en.wikipedia.org/wiki/Past_hypothesis

[1] https://en.wikipedia.org/wiki/Eternalism_(philosophy_of_time...

Interestingly, the norm of your 4D speed vector is constant, IIRC: https://en.wikipedia.org/wiki/World_line

Recently, I came across the Feynman-Wheeler handshake[1-ish], which lead to the Transactional Interpretation[2] of quantum mechanics, which lead to the Afshar experiment[3]

I've come to conclude that all of these are consistent, but that they are a metaphorical truth, in that you shouldn't interpret them as literal truth.

Gun safety advocates teach "All Guns are Loaded", another metaphorical truth. If you behave as if it were true, you will generally live longer, and be safer.

The math underlying quantum mechanics has all sorts of non-intuitive interpretations, and is often used as a gateway to woo-woo theories. I'm allergic to woo, and thus treating all of this as a metaphorical truth works best for me.

[1] https://en.wikipedia.org/wiki/Wheeler%E2%80%93Feynman_absorb...

[2] https://en.wikipedia.org/wiki/Transactional_interpretation

[3] https://en.wikipedia.org/wiki/Afshar_experiment

This comment will probably give you hives, but the inability to interpret things like QM literally and the inability of the left brain to process things holistically seems relevant to the interpretability problem. See Iain McGilchrist's "The Matter with Things". (I promise it's less woo-woo than it appears)

I started watching an interview with McGilchrist about the work in question, there was no physics, just a boatload of philosophy.

It turns out I don't need physics to be interpretable, just a workable predictive tool.

Fair enough. According to his thesis, the metaphysics/philosophy aspect of this stuff is in a right hemisphere bucket. While there may be reason to meditate on that if you’re a researcher wanting to gain better intuition, if you want to use physics as a tool, the aspects useful to the left hemisphere are all you need/the thesis is irrelevant.

You have confused "metaphorical truth" with "heuristic". You can actually verify that a specific gun is not loaded and thus know for certain that not all guns are loaded, this (among several other things) means it really isn't metaphysics at all..

Metaphysics are u

> I'm allergic to woo

Funny that your entire comment is woo.

It's an article about QM.

On Vice.

About a QM thought experiment.

On Vice.

Why would there be any expectation of scientific rigor whatsoever?

"retrocausality, may seem like science fiction grist at first glance"

Stop there, vice.

https://en.wikipedia.org/wiki/Ad_hominem

Technically, Vice isn't a human.

hmm... Vice might be incorporated.

Corporations are people too

https://en.wikipedia.org/wiki/Corporate_personhood

Ugh this point is so old. Corporations have “legal personhood”, which shares almost nothing in common with actually being a person in the understood sense. It’s just a legal term, in the same way a state of matter and a state in the US have nothing in common except the same letters make up the term.

Since the only sense that “person” matters to ad hominem really is as an entity making an argument, a corporation (or any other collective entity, with or without juridical personhood) is a person in the sense required for the fallacy to apply.

(Also, juridical persons and natural persons are a lot more similar than US states and states of matter; it is not just a distantly related etymology; the former literally refers to having legal attributes of the latter.)

Feel free to use “ad entitatem” instead. I don’t think it diminishes the point in any way.

I think https://en.wikipedia.org/wiki/Michael_Crichton#GellMannAmnes... is applicable here.

the comment may be superficial and dismissive without pointing out factual issues, but ad hominem attacks are still a very different thing than dismissing the credibility of a publication that has a track record of misleading pop science sensationalism

> dismissing the credibility of a publication that has a track record of misleading pop science sensationalism

Attacking the publication's track record, rather than the article's content, is clearly covered by PP's cited definition:

"a rhetorical strategy where the speaker attacks the character, motive, or some other attribute of the person making an argument rather than attacking the substance of the argument itself"

Pointing out or calling out people posting BS, that is clearly BS, does not fall into any category of logical fallacy - those arguing the case that it does on the other hand ...

I've heard people in that field talk about the possibility of loops in the time dimension, but infinitesimally short period of time is involved and local. Not enough to call it the past though.

It’s playing the man and not the ball. Argue the point not the publisher. You’re arguing the point here, which is correct. Thinking that you can reject the point by diminishing the publisher is definitely a logical fallacy.

I do not know Vice's track record as per the credibility of their science write ups, nor if the General Editor is more concerned with filling white space while ensuring even if fluffy explanations make muster, fluffy fluff does not. Still the blame for fluffy fluff falls at the feet of the author and or their research team. I don't see the General Editor rejecting a story submission because it's true or has good grounds to arrive at given conclusions.

As far as rejecting the point outright, well for myself, I'm not in the string field or quantum physics, but I used to read some pretty reliable sources, and bleed back was put to bed a while ago (years) ... non event now as far as I know apart from a few people who missed that memo - but would consider the possibility there's been new discoveries the last few years and with new theories, the possibility is tangible once more.

It isn't an error to distinguish between credibility or competence attacks and logical refutation.

PP is technically - which is to say logically - correct.

> https://en.wikipedia.org/wiki/Ad_hominem

ad hominem? "add Vice and 'em", I say, to your list of unreliable sources, for exaggeration, arguments of convenience, burying any counter-evidence...

Hacker news has the best passive-aggressive link commenting anywhere on the internet.

This reminds me of an old joke my grandfather told me:

two hacker news commenters are climbing up a mountain

one of them loses his footing and falls on his butt, and asks the other to help pull him up

the other responds that this looks like a textbook case of slippery slope fall-assy and that it is beneath his intellectual dignity to even consider responding on the merits and further...

while he continues on the first commenter falls into an ice crevice and dies

Are you asserting that any topic brought up by any publication deserves equal consideration, even if one said publication has a track record of intentionally misrepresenting facts?

I ask this question without ascribing credibility or lack thereof for Vice, but just in general.

Check other articles by the same author.

Mostly a bunch of clickbait crap.

> "One 'Super-Earth' Could Destroy Our Own Planet, Study Finds"

> A super-Earth existing in our solar system is so far hypothetical, but its effects would be incomprehensibly destructive.

Lars von Trier has entered the chat.

Nice reference

https://en.wikipedia.org/wiki/Melancholia_(2011_film)

Is there any point to the comment? Did Vice made the theory up?

The main thing I didn't like about it was pretending it's all scientists involved and not philosophers. The article talks mostly about Huw Price—and from phrases like "Scientists, including Price", you'd think he's a scientist. He's an Australian philosopher. He was my professor for a couple of philosophy-of-science-related courses at Sydney Uni 20 years ago. He started the Centre for Time there I believe. He's a great lecturer—a very impressive mind and a nice guy. Not a scientist though.

https://en.wikipedia.org/wiki/Huw_Price

https://prce.hu/w/

Thanks for the links.

Is it bad to upvote an article on HN, just because I think the comment quality is enlightening? Philosophers professing to be scientists has been troubling me more and more the past few years.

Also, gotta say many of the top comments are pretty interesting here.

> Philosophers professing to be scientists has been troubling me more and more the past few years

Hmm, I don't recall ever coming across a philosopher professing to be a scientist.

> Is it bad to upvote an article on HN, just because I think the comment quality is enlightening?

Not bad—I and others do it all the time, when you want more people to see the existing comments and to comment more. Often the worst articles provoke the most interesting conversations.

> Philosophers professing to be scientists has been troubling me more and more the past few years.

Scientists professing not to be philosophers has been troubling me more and more the past few years.

Why does it bother you?

As Richard Feynman said, "Philosophy of science is about as useful to scientists as ornithology is to birds." Sure, lots of what scientists do, including Feynman, involve an implied philosophy. It is easy to read https://calteches.library.caltech.edu/51/2/CargoCult.htm or https://history.nasa.gov/rogersrep/v2appf.htm and extract a lot of important philosophical ideas from them. But I have yet to see any self-proclaimed philosopher successfully do so without totally losing the key points.

There was a time when I thought that philosophy must have something important to it, and philosophers must have something useful to say. So I wound up reading works by various philosophers that were recommended to me. Some works, like Meditations by Marcus Aurelius, were invaluable. Most weren't. The ones that were invaluable to me inevitably were written by people whose primary profession was NOT philosopher. For example Marcus Aurelius was a Roman Emperor.

After a time I learned that if an important philosophical point happens to be made by a philosopher, I'd prefer to hear it filtered through the brain of a non-philosopher. Every time I try setting this rule aside, I am reminded of why I adopted it in the first place. And so, even if I'm reading about something which is apparently philosophical, I skip past the philosophers.

Paul Graham offers an explanation of why this might be in http://www.paulgraham.com/philosophy.html. I don't completely agree. But I also don't have a better explanation to offer.

And I'll happily laugh at anyone who tells me that I should think of myself as a philosopher because I happen to be interested in a bunch of philosophical-sounding subjects like "philosophy of math", "epistemology" and so on.

Feynman was actually quite sophisticated philosophically eg. “The test of all knowledge is experiment. Experiment is the sole judge of scientific truth.” I think when there is a purpose to philosophy eg. understanding science, it works better. When there isn't really philosophers tend to in many cases just discuss what other philosophers have said about each other which tends to get a bit circular and pointless.

I think perhaps there's a subtlety in that quote - "philosophy of science is about as useful to scientists as ornithology is to birds".

Maybe part of the meaning, is that I'm the course of doing what scientists do, philosophy doesn't move their particular ball forward in the way they want so they can and sometimes do ignore it. Not necessarily that they should.

This guy helped create nuclear weapons, and then quoted the bagvad ghita and had a long time to think about it. I can't imagine it didn't occur to him.

> and then quoted the bagvad ghita and had a long time to think about it.

That was Oppenheimer, not Feynman.

D'oh. You're totally right; I was having a different conversation apparently.

Feynman attempted to make his speech simple, clear, and precise. It is almost certainly a mistake to read subtlety into his language.

Besides, he expressed his negative opinions on philosophy and philosophers in many ways, on many occasions. He very clearly was on the side of those saying that philosophers SHOULD be ignored by anyone who wished to learn science.

Indeed. Feynman was extremely good at getting to the heart of the matter with simple and precise language and no pretensions. This is why so many important ideas of a philosophical nature can be found in his works.

But conversely he had little patience with obfuscating the heart of the matter with unnecessary complications, overly complex or vague language, or pretension of any kind. But philosophers do all of those.

If you read Paul Graham's essay, which I linked to, his proposal for how to fix philosophy is to focus on usefulness. For exactly the reason you stated.

That, apart from the first line, seems like a pretty generic/off-topic "I don't get philosophy and it's stupid" rant that could equally well be pasted under any story involving philosophy.

I don't see how it relates at all to the comment you replied to, which I thought was a good one.

Let me explain how it relates.

The comment advocated that scientists should profess to be philosophers. Why? Presumably because they are engaged in a field of study that philosophers have claimed. Furthermore the author is bothered that they don't. Why? Likely because if scientists acknowledged their status as philosophers, that would raise the status of philosophers.

And so the meat of my comment was illustrating by anecdote that the fact that philosophers have claimed a field, does not mean that they contribute meaningfully to it. Nor that people interested in the field should pay attention to philosophers. Nor that they should call themselves philosophers. Therefore, despite the claim that philosophers lay to topics like "epistemology", scientists SHOULD NOT profess to be philosophers. And anyone who claims otherwise should be laughed at.

Now why did I make my comment?

It is because I saw the comment as being part of the genre of people who attempt to raise the status of their field by laying an unwarranted claim to the accomplishments of others. This offends me. Philosophy and philosophers do not deserve credit for the accomplishments of science. And should not demand that scientists give philosophy that credit by relabeling themselves as philosophers.

With all that said, hopefully you'll better see how I saw my response as responsive to the comment. And hopefully you'll understand why I did not find it a good comment.

> The comment advocated that scientists should profess to be philosophers.

This context is helpful, thanks.

I didn't advocate anything. I said that it bothers me is that (some) scientists profess not to be philosophers. This is because, in fact, scientists, like all people, actually are philosophers.

> It is because I saw the comment as being part of the genre of people who attempt to raise the status of their field

My field is not philosophy.

> by laying an unwarranted claim to the accomplishments of others.

Neither did I make any claims in my original comment. You seem to have extrapolated quite a lot from a single sentence.

> Philosophy and philosophers do not deserve credit for the accomplishments of science.

The origin of science is obviously philosophical; indeed, Western science is theological in origin (and so is Eastern if you want to broaden your definition of theology a bit). It is equally obvious, if perhaps a bit ironic, that modern science has distanced itself from its earlier foundations.

To the extent that all people are considered philosophers, the claim that person X is a philosopher is meaningless, and therefore is a statement that is not worth making. Just as I do not constantly go around identifying myself with, "human, primate, born on planet Earth, circling the star Sol, in the Milky Way galaxy..." Those statements are true but provide no useful information to anyone distinguishing me from anyone else.

To the extent that "philosopher" is identified with the practice of philosophy as discussed and practiced in philosophy departments, it is a meaningful identifier. But also *SHOULD NOT* be applied to most scientists. For similar reasons, the historical theological roots of early scientists does not make modern fields like chemistry into branches of theology.

As for science distancing itself from its earlier foundations, there is nothing ironic about it. In fact that act is essential to how science as a field operates. The purpose of a scientific education is to indoctrinate the student with the norms, values and knowledge of current scientific paradigms that will allow the student to operate within, extend, challenge, and hopefully improve those paradigms. Exposing the student to the details of outdated approaches only to explain why they became outdated is an activity of limited use, and therefore we strictly limit how many such examples students must learn. And even for those we do not explain previous ideas in detail. What purpose is there in explaining to students who must learn inertia, Aristotle's ideas that all things naturally come to rest? Why would we bother explaining the history of attempts to find mechanisms for and explanations of Noah's Flood to students who are about to learn about the Ice Ages and that Noah's Flood didn't happen?

The first clear description that I know of for this process comes from Thomas Kuhn's book, The Structure of Scientific Revolutions. At the time he was a physicist who had developed an interest in the history of science. He implicitly assumed a shared context with the reader. People who have mastered a hard science generally have that context. I have that context, and found the book delightful.

Unfortunately after writing that book, he spent a lot of time responding to creative misunderstandings of his work from philosophers who lacked that context. I found little value in those criticisms, or in his responses. Yet another example of how I've found a lack of value in philosophy as practiced by philosophers.

> To the extent that all people are considered philosophers, the claim that person X is a philosopher is meaningless

If ideas had no consequences, this might be true; but since ideas do have consequences, this is probably not true.

> For similar reasons, the historical theological roots of early scientists does not make modern fields like chemistry into branches of theology.

A theologian might disagree with you about this. How would you go about demonstrating that this opinion is incorrect?

> As for science distancing itself from its earlier foundations, there is nothing ironic about it. In fact that act is essential to how science as a field operates.

Scientific progress suggests that we produce more theoretically plausible interpretations of phenomena. As we do that, we often undercut or discard the axioms that produce these new theories: that is what is ironic.

> If ideas had no consequences, this might be true; but since ideas do have consequences, this is probably not true.

Let's start with the idea, "If all A's are B's, then there is no information contained in 'x is a B' that is not also contained in 'x is an A'."

It's a pretty important idea. It goes back to Aristotle. Anyone who professes to think that philosophy is important should be familiar with it.

Its consequence is that if all humans are philosophers, then there is no information we can extract from the label "philosopher" that is not already contained in the label "human". And therefore calling individual humans philosophers would therefore convey no useful information.

But attempting to apply generic labels IS useful for a well-known fallacy - the fallacy of equivocation. This is where the same term is used with two different meanings in different parts of the same argument. For example an ontological argument can produce a generic definition of God, then argue for its existence. And then proceeds to argue for a Christian God on the basis of characteristics we implicitly associate with the idea of God, DESPITE those characteristics not being part of the definition just used.

Therefore the attempt to apply unnecessary labels can lead us into logical fallacies. Such as arguing that everyone should be called a philosopher, then arguing about how philosophers should behave, then arguing that everyone should behave that way. And failing to note that the definition of "philosopher" changed between the first and second parts of the argument.

Given that the most likely consequence of calling everyone a philosopher is falling into logical fallacies, we should not assert a trivial definition of philosopher such that everyone is a philosopher.

> A theologian might disagree with you about this. How would you go about demonstrating that this opinion is incorrect?

I would argue from the meaning of the words used.

Theology is the study of the nature of the divine. To the extent that a scientist believes that they are revealing the nature of the divine from their study of the natural world, they are engaged in theology. However to the extent that the scientist makes no attempt to draw conclusions of the nature of the divine from their studies of the natural world, they are NOT engaged in theology.

Modern chemists seldom try to draw any conclusions either way about the nature of the divine from their work. Therefore the study of modern chemistry is not a branch of theology.

To the extent that theologians attempt to draw conclusions of the nature of the divine from chemistry, those theologians must be engaged in theology. But modern chemists will generally agree that those attempts are not part of the field of chemistry. And so, again, modern chemistry and theology are separated.

> Scientific progress suggests that we produce more theoretically plausible interpretations of phenomena. As we do that, we often undercut or discard the axioms that produce these new theories: that is what is ironic.

And what axioms would those be?

Science did not begin to become science until it threw away a lot of Aristotle's bad ideas. Other ideas of his were not thrown out, but have generally proven to be irrelevant. The logic used in practice by science owes rather more to people like George Boole, Thomas Bayes and Ronald Fisher than Aristotle. And students are more likely to encounter said logic in a mathematics course than a philosophy one.

That said, it is trivially true that the way that science is carried out demonstrates that they have adopted an implicit philosophy. But that philosophy was mostly developed by scientists themselves, and I've never seen it accurately described by philosophers.

This is not to say that philosophers have not tried. For example Karl Popper attempted to opine on how science must be done, and came up with his famous falsifiability criterion. This theory is laughably wrong. Scientists have known for many decades that one or both of currently accepted theories about general relativity and quantum mechanics must be false. And yet neither has been thrown out.

Nor is this merely a comment about how scientists fail to operate as Popper would like. POPPER HIMSELF attempted to do scientific work, and POPPER failed to behave as Popper claimed that scientists should. Very specifically, Popper to the end of his life refused to accept evidence that quantum mechanical particles do not have a precise position or momentum. And contributed decades of papers about experiments that he hoped would prove quantum mechanics wrong, and his ideas right. Eventually the experiments were done and, as was generally expected, Popper was wrong.

This was no surprise. By this point mainstream physics had long accepted not just uncertain position and momentum, but were happily using Feynman diagrams to organize calculations that included virtual particles with possible (but uncertain) temporary existence.

Even today, philosophers continue to opine on falsification despite the fact that falsification has long been falsified as a description of science. They are not alone. Some scientists like to muse on this and related topics. But when they return to their real work, they mostly ignore the giant contradictions between the theory and practice of science. So the best thing that I can say about it is that little harm is done.

> Let's start with the idea, "If all A's are B's, then there is no information contained in 'x is a B' that is not also contained in 'x is an A'."

All humans are primates, but not all primates are human: the two ideas are not interchangeable. I'm not equivocating; I'm simply saying that it bothers me when people who implicitly philosophize think or say that they are not.

> That said, it is trivially true that the way that science is carried out demonstrates that they have adopted an implicit philosophy. But that philosophy was mostly developed by scientists themselves, and I've never seen it accurately described by philosophers.

That a truth is trivial does not make it self-evident.

Methodological naturalism is not the same thing as philosophical naturalism, but many people (scientists and otherwise) conflate the two. Whether the philosophy is true or not is a metaphysical question, not a scientific one.

What exactly bothers you?

That someone who implicitly philosophizes says that they are not philosophers? To me that is no more bothersome than someone who speaks English telling me that they are not English majors.

Are you bothered that people like me do not value studying philosophers for the purpose of philosophizing better? But you have not made a case for why I should value it. I have made a case for why I don't value it, but you have not responded to or acknowledged much of it.

However I'll try again.

I maintain that the single most influential work of Greek ethical philosophy is Aesop's Fables. It is more read, more quoted, and its advice is more followed than everything else from ancient Greece, combined. Aesop, if he actually lived, could not have studied Socrates, Plato, Aristotle and the other famous philosophers for the simple reason that he predated them. But imagine that Aesop had the opportunity to study and cite them. Would Aesop have been more effective and influential had he done so? Instead of telling relatable stories about animals?

Obviously not! Aesop's philosophizing was made more effective BY his lack of concern for the norms of classical philosophy!

I do not think that this is an isolated example. Norms of behavior are more easily established and absorbed through practical stories than abstract debate. This is as applicable whether it is Aesop instilling a moral about hard work with a story about ants and a grasshopper, or Feynman instilling a moral about the necessity of careful replication experiments with a story about a cargo cult whose planes don't land.

It is too bad that few in psychology paid any attention to Feynman. They could have saved themselves decades of wasted work. But in time the replication crisis brought home the point that their failure to absorb scientific norms was resulting in fraudulent fields which followed the forms of scientific research while producing results that nobody should trust. But I digress.

> That a truth is trivial does not make it self-evident.

This comment is hilariously true when it comes to how mathematicians use the word "trivial".

That said, I believe that you understand and agree with my point that scientists have adopted an implicit philosophy.

> Whether the philosophy is true or not is a metaphysical question, not a scientific one.

And here I have to violently agree. If, in fact, you're concerned with Truth with a capital T, then science really isn't the field for you. Because science has learned the hard way not to try to answer that question. So go off and debate it with the philosophers.

But if you wish to understand the world, science has a lot to commend it. There is a necessary chunk of implicit philosophizing that you must absorb to learn it. But you will not find it taught in philosophy courses, nor will studying philosophy help you to absorb it.

> That said, I believe that you understand and agree with my point that scientists have adopted an implicit philosophy.

Before getting to the main body, this was precisely the point I was making in my original response. That is exactly the point. The rest of this is probably wasted electrons, but they're relatively cheap and I've spent them already.

> What exactly bothers you?

That's a good question with which I've wrestled. A couple introductory notes:

Despite the terseness of my replies, I do try to make them thoughtful. My time is limited, and I have found that less is more when writing. I have read what you wrote, but yes, I'm a bit choosy in responding because the content easily spreads well beyond the original intent of my response and my time boundaries. Apologies to Pascal, but I'd have written you a shorter comment if I had the time.

My intent was to correct a few assumptions that you made about me based on the comment—not to convince you that my perspective is correct or to argue that the term philosopher should not be restricted to those who are educated in the field, or even that scientists should be trained in philosophy (although I think the basics of how we approach the human condition would be useful).

None of the following may apply to you personally; I don't assume that they do, and indeed given our conversation suppose that most of them don't.

So, why would it bother me that scientists profess not to be philosophers?

1. Because all people are philosophers (or theologians, or both). That this is trivially true does not mean that people recognize this fact about themselves; scientists are no exception.

2. The scientific method is not a neutral approach to acquiring knowledge; some people suppose that it is, and in so doing they're making a philosophical statement, not a scientific one.

3. The application of that knowledge is obviously not always neutral, and it can have profound consequences.

4. We should generally be more aware of our own lack of neutrality.

5. Science is gradually (or not-so-gradually) replacing our myths and today serves much the same role in answering our questions about who we are, where we came from, where we're doing, and how we're getting there. In other words, science for many people is becoming philosophy (or theology, or both).

6. When scientists fail to recognize this, they may exacerbate the problems we face trying to answer those questions. They could help avoid this, perhaps, by understanding that they are the modern equivalent of high priests (whether they will or no).

This is not to say that science has no role in answering life's big questions; indeed, it does and probably should. But we cannot go from is to ought, or at least history teaches us that doing so is not conducive to human flourishing. Neither is the transition from knowledge to wisdom immediate or obvious. I know you agree with these statements.

The difficulty I have is that many people elide these distinctions with upturned nose, not realizing that they are turning science into scientism. This might be an avoidable outcome.

Let's respond point by point.

1. I cook food for myself, but do not call myself a chef. I have managed to not kill my lawn, but do not call myself a farmer. Why then should the fact that I have opinions about philosophical topics and the existence of God qualify me to be a philosopher and theologian?

2. The fault for believing that the scientific method is a neutral approach to acquiring knowledge lies with those who believe it, and not scientists. For their part, scientists tell the story of the drunk who is crawling on his hands and knees around a streetlamp. When asked what he is doing he replies, "I'm looking for my wallet." When asked where the wallet was dropped he replies, "By those bushes." When asked why he's not by the bushes he replies, "But the light is better here!"

Scientists are very clear that they are looking where the light is good. Instead of where the answers to the most important questions seem likely to be found. Most are also clear that doing otherwise would stop them from being scientists.

3. Scientists are seldom focused on potential applications, usually can't predict what they may be, and when applications appear, are usually not in control of them. So while I agree that applications are not always neutral, I do not agree that scientists should be doing anything differently because of it.

4. We should be aware of our lack of neutrality, but I see this as advice that is best directed at influential non-scientists. And not advice that is actionable by scientists.

5. There is a long history of people cherry-picking what they want out of science, and using it to advocate for whatever positions they may hold. History shows that the support, opposition, or indifference of scientists does not much impact this. You may verify by looking at the history of Social Darwinism, Christian Science, Scientology, or Ram Dass' invocations of quantum mechanics. Given this history, why would you believe that scientists can much impact what non-scientists say and do in the name of science?

6. To the extent that scientists are the modern equivalent of high priests, they are learning what the priests have always known. They only have power to the extent that they say things that the public wishes to hear. Which winds up being less power than it would appear.

Here is an illustrative example. Jesus told us that it is easier for a camel to fit through the eye of a needle than for a rich man to get into heaven. And yet, this very night, millions of his followers will pray for the very wealth that Jesus warned against!

I bring this up not to argue for a specific theological interpretation, but to make a point. Suppose that a preacher at a megachurch were to decide that Jesus was right, and this should be the subject of every Sunday sermon until his flock properly followed Jesus' advice. I predict that his flock would soon find new churches with preachers that they prefer listening to. And the preacher who thought he shaped the minds of thousands, would find nobody listening to him.

Scientists are in a similar position. Except that they are trying to follow knowledge where the light is good. They neither wanted nor are suited to a role as preacher. And so they properly avoid stepping into the role, let alone stepping into it for the purpose of following the agenda that you wish that they would follow.

You somehow believe that there would be value in pressuring scientists to behave otherwise. I don't.

https://existentialcomics.com/comic/447

"There's nothing more annoying than people believing the same thing you do for dumb reasons", ouch ...

The only thing more annoying than that is when you pick a fight with them about their reasons and they insist on believing that you must disagree with their conclusions.

I would imagine that the vast majority of people working at a place like vice don't understand the distinction between soft and hard sciences, don't care about the distinction, or are bitter about the distinction.

Philosophy isn't anywhere on the Mohs scale of sciences—it's not a science at all. Each philosopher has their own idea about what philosophy is, but I'm not aware of any who think it's a science. That's one way to tell the difference—a philosopher asking "what is philosophy?" is doing philosophy. A physicist asking "what is physics?" is doing philosophy, philosophy of science. Actually it's mostly philosophers who ask that.

Science was originally[0] a part of philosophy—natural philosophy—but that's a different story. Part of Socrates' originality was that every previous philosopher concerned themselves with physics and other physical sciences, but he was just concerned with the human world.

https://en.wikipedia.org/wiki/Mohs_scale

[0] And until quite recently! The word scientist was only coined in 1834. And "The predominant modern use [of the term "science"], "natural and physical science," generally restricted to study of the phenomena of the material universe and its laws, is by mid-19c."

https://www.etymonline.com/word/scientist

Not entirely true

https://plato.stanford.edu/entries/qm-action-distance/

> Not entirely true

If you want to communicate anything by that, please explain what you're referring to. I'm not going to read that entire page trying to guess. I can't at first glance see anyone asking "what is physics?", if that's what you meant.

The Stanford encyclopedia of philosophy includes topics from quantum mechanics.

Not the one you're replying to... So what? I still don't get what your point is. Including quantum mechanics topics in a collection of articles doesn't make that collection science.

I guess you could say philosophy is a protoscience.

Exactly this, all the other sciences were a philosophy before they grew and got 'codified'.

Time in physics is operationally defined as "what a clock reads". Nascent sciences start in philosophy.

"Time is defined such that motion is simple" is a bit of physics-genius from MTW

It’s common amongst journalists, certainly of late.

This is not entirely correct. I can't say on this "retrocausality" stuff in particular, but more generally in quantum foundations, there are a lot of philosophers with a very solid physics/math background who have a better understanding of quantum than most physicists. I find quantum foundations to be not very interesting personally, and I doubt it will have much relevance 20 years in the future, but some philosophers working in it are definitely worth taking seriously.

> This is not entirely correct.

Which part? I didn't say or mean to imply philosophers are not worth taking seriously—if that's what you meant—just that philosophers are not scientists, and in particular, Huw Price is not a scientist. Uncontroversial, I would've thought.

An article titled "A growing number of scientists.." that then misrepresents Price as being a scientist, is the thing that's wrong, seems to me. Maybe it did that because "A growing number of philosophers.." wouldn't have anything like the same click-appeal.

Scientist isn't a job title or a qualification, it's a word for someone doing science. Some philosophers working in quantum foundations deserve to be called scientists, as much as any theorist from the physics department in the field. Price may not be in this category, you certainly would know better.

Couldn’t read it anyway because of the ridiculously intrusive ads.

Sure, journalists need ads to make money but this way too much.

They cite a preceding article, though I've no idea if 'the conversation' has any more gravitas (literally first I've heard of it).

https://theconversation.com/quantum-mechanics-how-the-future...

That article is written by the same philosopher Price.

The Conversation is a site where academics blog about their papers.

It does make explaining some things much easier, like the "Delayed-choice Quantum Eraser"[0] experiment.

Basically what's possible next is anything that can solve for conditions set by the past, and some from the future.

[0] https://en.wikipedia.org/wiki/Delayed-choice_quantum_eraser

I think it relates more to Wheeler's Anthropic Participatory Principle[0], where multiple observers of some event in the past, can influence it from the future.

0: https://en.wikipedia.org/wiki/John_Archibald_Wheeler

> A growing number of scientists...

Beware, getting from one to two is already a growing number!

that's actually a big jump, 100% increase

It's growing exponentially, perhaps even factorially.

The Transactional Interpretation of Quantum Mechanics also says this[1]. Retrocausality and non-locality are why a lot of physicists don't like it. It's just an interpretation too, but is otherwise consistent with all other QM theories.

[1]https://en.m.wikipedia.org/wiki/Transactional_interpretation

A growing number of people are recognizing that this article was published in VICE, which isn’t exactly a reputable STEM magazine, as punctuated by the fact that the article refers to theoretical physicists as “people” or “scientists”.

You gotta think about the (stoner) audience this article was written for, I wouldn’t take too much stock in its conclusions.

The final episode of Star Trek: The Next Generation played with this concept [1].

1. https://en.wikipedia.org/wiki/All_Good_Things..._(Star_Trek:...

Well, of course, what happens tomorrow dictates what happens today. It's hard to be sure about what happens tomorrow. Then again it's hard to be sure about what happens yesterday. It's not a one-to-one relationship, but there are striking similarities.

Interesting because it messes with the school of thought that everything is determined already and we're just following a sequence of actions that arise from the starting conditions of the universe. If causality is broken then maybe we have free will?

That's a very lazy school of thought though. It's just atheistic Calvinism, a tautology masquerading as a "philosophy".

Calvin believed in pre-destination (your fate and every decision you make is decided before you exist) on the grounds that, because God exists and is omnipotent, what you are doing must therefore be what God wants to happen, both good and bad. After all, God is omnipotent, so there you go.

Today's Calvinists just replace God-driven destiny with nature-driven destiny, but the underlying tautology (X exists, therefore X was always destined to exist, as proven by the fact that it exists at all) remains the same. In fact, it's an arguably more ignorant version of Calvinism, because it requires that one completely dismisses any knowledge they have of probability theory. So it's the "smarter" Calvinism that requires you be ignorant of 20th century mathematical advances.

Hate that crap. The only people I hear talking about it are silicon valley utopians, which is probably the other reason I hate it.

> In fact, it's an arguably more ignorant version of Calvinism, because it requires that one completely dismisses any knowledge they have of probability theory

No to pick too many nits, but I think it is well established that knowledge of formal sciences (i.e. mathematics) does not impart knowledge about natural sciences (i.e. physics). While maths a useful tool, there are no established rules of inference for reality, and without rules of inference you can't really make claims on infinite sets.

Natural sciences allow us to find mathematical constructs that make good predictions within specific constraints or that have not yet been falsified, just because something is true in probability theory does not make it true in reality.

If humans lacked free will, probability would still be useful, because humans use it when they have imperfect information about an upcoming event.

> In fact, it's an arguably more ignorant version of Calvinism, because it requires that one completely dismisses any knowledge they have of probability theory. So it's the "smarter" Calvinism that requires you be ignorant of 20th century mathematical advances.

I entirely fail to see how probability theory means it's impossible for the universe to be deterministic.

I don't follow this argument. The coexistence of probability theory and strict determinism create no issues in modern mathematics.

If causality is broken, that means hard indeterminism.

It could just mean causality has more dimensions than we can perceive. It doesn't mean it is nonexistent.

So my decision to have a ham sandwich for lunch is determined by some meta-universe that created the starting conditions for this universe, and allows for the breach in causality? Or somehow is involved in the backwards-arrow of quantum events that the article talks about so the universe cannot turn out any other way?

I dunno, seems like a "God of the gaps" thing - we can speculate on meta-meta-universes endlessly. Including one where my decision to have a ham sandwich disturbs the state of a yet higher dimension that sets the starting parameters of your higher dimension and once again I have free will.

Right, physicists seem to generally agree there are parts or dimensions of the universe we cannot directly measure. If scientists can't predict whether you will eat a ham sandwich for lunch or not, it won't be clear if they can't predict it because you have "free will" or because we have limited access to information on how the universe works.

Scott Aaronson's "Ghost in the Quantum Turing Machine" tackled this question in a way I found enlightening. It's a bit of a dense read (I needed a plane trip to sit down and focus on it), but it presents a compelling case for the possible reversal of time arrows when it comes to the effects of quantum indeterminism on macro scale interactions. In short: what if humans, somehow, someway, have the ability to "influence" the resolution of unobserved universal start-state quantum noise in order to affect our "will" onto the universe? Furthermore, what experiments could be done to validate or invalidate aspects of this hypothesis?

https://arxiv.org/abs/1306.0159

That seems crazy - that my decision to have a ham sandwich for lunch had to be propagated all the way back to the start of the universe in order to happen ;)

And yes, provability is a major problem with all these kinds of theories. We don't have a parallel universe handy as a control, and just saying "I am not going to have a ham sandwich tomorrow" isn't a viable experiment.

I interpret it as a sort of entropic antennae... each person (brain? qbit?) is tuned into what might be considered an allocated "entropy bandwidth". Some decisions, like whether you eat a ham bandwidth tomorrow utilize* practically none of that bandwidth. Others, what you might consider "major life decisions" might utilize* a ton of bandwidth. Some people might be gifted with a "larger" antennae, allowing them to utilize* a higher amount of entropy per second, or per lifetime. We might call these great artists, or generally any genius-level intellectuals. Alternatively, bat-shit crazy people.

*: On "utilize". A central debate (the central debate?) seems to be what sort of "state access mechanism" this maps to in our lexicon: "{reading|writing} {global|local|shared} {bandwidth|memory}"

>had to be propagated all the way back to the start of the universe in order to happen ;)

Technically, casualty required that anyway. My understanding that it's infinity in space, not time that matters here. i.e. predicting your decision to have a ham sandwich may require predicting the entire universe and since we're part of the universe and can't look from 'outside' that decision would be unpredictable from inside the universe.

>And yes, provability is a major problem with all these kinds of theories.

I think showing that quantum effects are negligible for human brains would do, at least regarding your decision to have a ham sandwich?

Mmm, not really unpredictable, it is easy for thought exercises to avoid the dirty real world, but in the real world, Large Language Models have recently proven that many quite difficult abstract probability exercises, when taken to the real world and applying training, can be succesfully solved well beyond our most wildly expectations of precision, speed and accuracy.

So yes, the prediction of the decision to have a ham sandwich tomorrow, for any given person is now, by the state of the art of applied mathematics and information science, a relative doable - if not plain easy - feat.

And according to some hypothesis, the brain could be doing this exactly kind of predictions, even more better than LLMs, with more accuracy/speed using way less energy.

> the prediction of the decision to have a ham sandwich tomorrow, for any given person is now, by the state of the art of applied mathematics and information science, a relative doable - if not plain easy - feat.

Sure, the LLM may be able to guess by reasoning (e.g. 'He always eats ham sandwiches for breakfast and he probably wouldn't break his routine'), the same way we could guess at another person's behaviour, but we're talking about reducing the brain into a deterministic input/output machine, which is a far larger ask.

Now if you said 'doable' that may be right in the long term, but 'easy'? Absolutely not. There's no current way to feed 'me' or 'you' into an equivalent LLM. The human brain has more axons then there are stars in the galaxy and we are nowhere close to even mapping these connections.

>The brain could be doing this exactly kind of predictions, even more better than LLMs, with more accuracy/speed using way less energy.

That's definitely an option. The fact that many of the brain's operations could be done by LLMs is a strike against the original thesis.

Y'all talking around the central point of the paper, btw. If this interests you, I suggest diving in.

The compatibilist view is that there is no contradiction between free will and determinism, because free will refers to macro states and determinism refers to micro states.

In addition, in the many-worlds view of quantum mechanics, we don’t follow just a single sequence of events, but all physically possible sequences of events, where the points where sequences branch off each other can correspond to different decisions we “freely” took. Meaning, when we make a decision, all applicable options of choice will become actual reality.

Where exactly might the free will be, then?

Compatibilism is a fancy way of saying "free will so much does not exist that what determists call free will isn't even a valid definition to use as a starting point for investigating an answer." It's not an answer to the question, it's a denial of it.

Another, simpler interpretation of Compatibilism is "if free will doesn't exist, then believing it exists or not has 0 effect on anything, because our beliefs are predetermined, and so at human scales the answers Yes and No are equivalent in all observable ways".

Definition is theory, free will is reality. When they diverge, it's theory which is improved to match reality, not the other way around.

My favorite sentence on free will comes from Chomsky (who I think was probably quoting someone else): "if we don't have free will, then why are you arguing the point?"

Causality isn't broken; the universe is "simultaneously causal and teleological," because it's superdetermined.

There also isn't any free will, because there isn't actually any agent who could have it. Actions we perceive as volitional actually arise in the brain up to 7s before we "choose" them. The sense of a "me" is a post hoc add-on that claims credit for everything, in order to unite the disparate phenomena that comprise the sense of self.

There isn't actually any "me," and recognizing this is what the word "enlightenment" refers to.

Again this seems like a "God of the gaps" thing - if this universe isn't strictly deterministic then it's superdetermined by a meta universe, and so on

What if the "so on" is infinite?

Turtles all the way down ;)

I think it's the opposite. You need a "God of the gaps" in the form of a "person" (actually a collection of phenomena. + the phenomena of identification with these) to explain free will and agency, which defies experimental evidence.

The comment that superdeterminism requires a higher-order determinism, which itself requires a yet-higher-order determinism... I think you're confusing it with a causal mindset. If the universe is effectively a recording, why does it need any ultimate cause? Causal thinking would only make sense from a perspective within that recording.

Of course we want to know "why is any of this here?" But what if the ultimate question doesn't actually have an answer?

> There also isn't any free will, because there isn't actually any agent who could have it.

The compilation of each possible Play in an Extensive Normal Form Game into a cellular automata can constitute a refutation by counterexample of your claim. It satisfies the agent condition through congruence with the technical language defining the concept of agent in artificial intelligence literature as it relates to agents in multi-agent multi-step decision theory problems. The condition of non-deterministic policies is found and shown to be optimal by Nash's justification for an mixed strategy equilibrium. The underlying mathematics that leads there is proven via Russel and there exists various proofs of the desiderata of probability from others which can begin atop that. Furthermore by compiling the formal system to get a physical system we create the ability for a logical analogy between the formal system and the physical system through Aristotle's analogical congruence concepts. We can count the cell configurations and we can count the transitional structure, but this is mostly a formality since we know through the definition of the compilation that they must agree. As far as I can tell at every single step in the laddering up there are proofs from the basics of logic to the mathematics to the use of probability to the justification through utility theory and even to the computational universality necessary to create the physical embedding of the agent in our reality.

The prior conception of guess appears laughable posterior to computation and comparison with evidence, but is just science prior and seeing it is wrong is hindsight bias posterior. It might sound laughable, but it is actually the case that it is not a laughing matter [1]. In like manner, but slightly different and perilously close to being anti-scientific is that you don't know until the observation whether guesses would go one way or another.

[1]: https://www.youtube.com/watch?v=EYPapE-3FRw

I'm saying your self-concept is only a useful abstraction. It's an evolutionally beneficial illusion that there is any entity called "me" that chooses which action comes next.

The mathematics of intelligence in multi-agent decision problems implication gives us informed guesses about what we should expect to see if an agent has free will versus if they don't. You are arguing with words like illusion, so I don't think you realize this, but what you actually need to provide to have your actual position be the consequence of experimental evidence is evidence of extreme compression being possible. Illusion? It is the evidence for agents, not evidence against agents, according to the theory informed guesses.

There is this story about a village of blind men and elephants. You are like a blind man from that village, saying that the elephant must be abstract because you felt a footprint of the elephant. Try playing with an elephant carving. It predicts footprints when you press it it into the ground. You can totally guess before you touch the elephant on the basis of the carving. The decision to focus on the untestable is a commitment to a hindsight fallacy which experimental investigation would likely refute.

I get what you are trying to say, but it isn't true. This is the long version that explains why and goes through the implications at each step showing the hypothesis, predictions they make, and why your views don't make sense. You should read this if you don't think my other post makes sense, but if it just clicks you don't need to read this.

H0: Free will predicts in advance of a decision problem that when a decision problem is resolved you cannot always predict the result.

H1: A lack of free will predicts of a decision problem that when a decision problem is resolved you can always have predicted the result in advance of the result, because there was only one possible resolution.

Complete Refutation of H1: The existence of halting problems. A self-reference in a decision problem refutes H1, because the self-reference

Additional strong evidence against H1: All the most successful epistemological frameworks suppose a superposition over positions which on attaining information about the next position resolves, not to a position, but to a new superposition. For example science does this. It believes we don't know for certain the theories, but we conjecture guesses and use observations to test them.

Implication of failure of H1 and the failure to refute H0: There exists a self-reference, a sort of self-concept, which prevents the resolution of a prediction prior to the resolution. Self-reference exists as a thing which must be computed.

Okay. So now we pick back up in the mathematics that deals with self-reference in game theory. In it we find equilibrium concepts which are defined with respect to self-reference and proven relative to self-reference considerations. These proofs show that the solution structure contingent on self-reference is non-deterministic.

Implication: Not only does self-reference exist, but the consequences of self-reference is the use of self-reference to refute self-referential prediction or to support self-referential prediction on the basis of utility of doing so or not doing so.

So now we know a self-reference must exist, we also know it predicts a refutation in some cases of the ability to predict it. We can also see that if the self-reference didn't exist, it would imply that there was no structure which wasn't computationally irreducible like self-reference structures are.

H3: We will see everything is predictable from the information contexts available, because agents don't exist. Example predictions: that all physics will be determinable like the position of a planet is determinable.

H4: We will that some things are not predictable, because of the existence of illusions that prevent resolution and which contain a self-reference consideration.

What we actually observe is H4. We observe H4 in at least one case, so we can't infer from H3 that we can reject H4, because H4 already rejects the safety of H3.

Let me give an example: Some deer in Africa don't see orange. Tigers, to us, are orange. To the deer they are green. The tiger color is decided by a self-reference consideration with the deer perceptual system. The deer is not going to be able to predict the future state of all tiger like we could predict the planets, because the deer is caught in a superposition with respect to a tiger's presence. When it observes a tiger, this looks the same as observing a bush. Therefore, even if it sees a bush, it can't predict that it can always model the consequence of a bush. Therefore, if we see a planet, it is incorrect to assume we can always predict the consequences of seeing a planet.

So now you can understand, if my other comment didn't click, why appeals to illusion are actually evidence for self-reference, not evidence against it. So feel free to read that comment again to see if it now clicks.

And yet doesn't it defy probability that such raw physical determinism would lead to us having this discussion? And if not, is it not amazing that simple subatomic physical applied to a gaseous soup leads to us discussing these questions?

To the first question, not in the least. This discussion is also superdetermined, including the illusory sense of a "me" who "chose" to write these comments.

To the second question, yes. It's beyond comprehension and wondrous. It's maximum novelty and total absurdity.

Might be worth it to brush up on computationally reducible phenomenon and computationally irreducible phenomenon. Breaking determined systems into these constituent parts lets you conjecture with respect to intelligent agents. Critically it shows that arguments from observed inability to successfully model the self are evidence for, not evidence against, the presence of an intelligent agent. The enlightenment view misattributes the evidence for agents as evidence against agents.

An anti-enlightenment koan could be: The student came to the master and asked, “Why are tigers green?” The master responded, “The deer they are hunting can’t see orange.” The student then asked, “It is not therefore it is? How mysterious and inscrutable your answers!” But from that moment onwards the master was de-enlightened.

There's an interesting short story "Story of Your Life" by Ted Chiang that is related to this concept.

It was the motivation for the movie arrival (though IMO is much better - the movie adds some drama that does not exist in the short story)

Phenomenal film. Full of interesting ideas and heartache. Pairs well with Annihilation.

Another point for my favorite minority quantum mechanics interpretation, two-state vector formalism (TSVF).

Where can I read the report?

https://arxiv.org/abs/quant-ph/0105101v2

“It’s important to emphasize at this point in time, whatever that means, that retrocausality is not the same as time travel.”

The funny line there is at this point in time. The whole article is about how the future influences the past so… at some point in time retrocauslity will be the same thing?

Retrocausality is like time being cooked spaghetti instead of dry. Or even macaroni. The world line is not "parallel" to the time line. Like the One Electon Universe idea ofositrons as time-reversed electrons. The article doesn't define time travel precisely, but presumably they mean discretely jumping ahead or back without passing through interventing moments.

Honestly it’s been staring us in the face for 100 years. Light doesn’t experience time. We’ve known this for so long. Light is created and destroyed in the same instant - across billions of light years it happens instantly. For that to be true, what else must be true? Must.

There is no photon. There is just a wave. The interaction probably (definitely?) depends on features of both the emitting electron and absorbing electron. There is either retrocausality or superdeterminism (or both). We don’t know which. Right now that’s not important but scientific fashion has been refusing to get this one thing. We’ll learn so much once we move past this.

Light going into a black hole? Research paper.

I don't think there are any logical arguments against superdeterminism, except spirituality. Even non-super determinism and Penrose quantum consciousness just pushes the superdeterminism into a unobservable metaphysical corner.

I'm attempting to recall an analogy from a paper about this subject. One of the authors gave the analogy of time being like a river. If we are traveling down this river, and the river is changing speed ahead (maybe due to rocks or a sharp bend), then it is correct to say that the river is changing the past (our present location in the river), since our speed would then start to change as we approach the new point.

> “You have to be very careful in a retrocausal model because the fact of the matter is, we can't send signals back in time,” Adlam explained. “It's important that we can't, because if we could, then we could produce all sorts of vehicles or paradoxes. You have to make sure your model doesn't allow that.”

This rings false to my scifi-trained brain. Paradoxes emerge when information about the future allows you to change it in some way. But if the future is truly immutable, there's no reason why you can't learn what it will be. Any attempts you make to alter it will only result in the exact thing that you already knew would happen.

Maybe I'm misunderstanding the author. Maybe what they MEANT to say is if you didn't already receive an email from your future self 5 years ago, then you can't send one today that your past self will receive at that time. Just as the future is immutable, so is the past. But if we had some sort of quantum email that allowed for such a thing, it WOULD be possible to go check it today and find a message from yourself 5 years in the future.

I'm guessing it's in terms of quantum information. Quantum entanglement and tunneling can happen faster than the speed of light, which causes similar time paradoxes with special relativity. This is avoided by the impossibility of sending observable classical information. Two entangled objects can affect each other, but you can't get actual information about it, because it is destroyed upon observation.

Asimov's The Last Question is all I can think of.

https://en.m.wikipedia.org/wiki/The_Last_Question

Why would I want to read about science in Vice, as someone actually interested in physics, but knowledgeable enough to understand a talented science communicator(with a PhD in the field) like Sean Carroll or Rebecca Smethurst.

What purpose does it serve to write sloppy interpretations of complicated, likely to not pan out hypotheses(almost always the case) on quantum mechanics?

So if this doesn't pan out, all they accomplished was that now a bunch of people are walking around with wrong information.

If it does, then we'll find out eventually anyway.

Science journalism is not useful to scientists, not helpful to nerds like me and for the masses it only contributes to misinformation and miseducation.

There are plenty of talented communicators with advanced degrees in their fields that can do this job better, and journalists should go do their jobs which is the opposite of regularly misinforming the public(inb4 cynical reply hurr durr journalists always misinform about everything <direction> wing media herp derp. Not interested.)

>...retrocausal models also open avenues of exploring a “time-symmetric” view of our universe, in which the laws of physics are the same regardless of whether time runs forward or backward.

... or sideways!

If you want a visual model that may help to build some intuition about that, I have one at [1]. Retrocausality is not explicitly spelled out in that model but "it's uh... uh... it's down there somewhere".

[1] https://github.com/OlegMazurov/Janus

Cool theory... A bit too Asimov for me though

https://en.m.wikipedia.org/wiki/Thiotimoline

>"But what if this forward causality could somehow be reversed in time, allowing actions in the future to influence outcomes in the past? This mind-bending idea, known as retrocausality, may seem like science fiction grist at first glance, but it is starting to gain real traction among physicists and philosophers, among other researchers, as a possible solution to some of the most intractable riddles underlying our reality."

Linguistics: retrocausality -- is going into my 2023 lexicon...

I have also come to this conclusion. I have had experiences that cannot possibly be explained unless at least some future events already exist.

This also explained the "probabilistic" nature of quantum behaviors; it's only probabilistic to us because we are unaware of the influence of future events. I now believe it's extremely likely that the universe is superdetermined, and I gave up the idea of actual free will long ago.

Highly recommend "Time Loops" by Eric Wargo.

Superdeterminism is a cop-out where the universe is simultaneously the only existing one and the most common possible one, for no obvious reason.

But yeah we'd like to think there's just one past and multiple different futures, but the fact that the laws of physics are time-reversible kind of makes it unlikely for both to be true.

Could you please expand on the experiences that you have had, that can't be explained without future events already existing?

> I have had experiences that cannot possibly be explained unless at least some future events already exist

you can't just drop something like this and then walk away without telling the rest of the story

A very common thought in speculative Design. Eben if it is a bit true event in the future, an imagined event can change the present as the perception of the past. See utopias and dystopia as example. If we say this known known in the future it already affected the present and also the past. It gets interesting for the unknowns unknowns if those will change the past and present. But already accepting that there unknown unknowns changes the present.

When you flip that dx/dt so it becomes dt/dx...

IMHO, it’s not even wrong … let’s not waste time on it.

The idea that there are "causes" and that there are "effects", and that these are separate and distinct, is in some way on a parallel with the idea that the past influences the future, and vice versa. If we think that the past influences the future, then it's just as reasonable to think that the future influences the past. Personally, I view "causes" and "effects" as abstractions that we use to help interpret our complicated world, nothing more.

That's not to say that it's not legitimate to talk about causes and effects and to reason using them, but when seriously considered, anything that absolutely looks like definitely a cause or an effect, needs to be considered again with the system boundaries re-drawn, that is to say, with the system boundaries drawn around the whole universe.

Take for example the cigarette lighting the forest on fire. Saying that the cigarette caused the fire is as much of a value judgement and political statement as saying that the decades-long drought caused the fire, or that humans causing global warming caused the fire, or that the cigarette companies caused the fire, or that God caused the fire. The emotional response that each of these statements elicits in various people should tell you that any statement linking cause and effect is emotional and political at its core. This reflects the nature of the humans that create these statements.

We have a built-in tendency to try to assign causes to events and effects. We should zoom out enough to understand that this is part of our humanity, not part of the way that the universe works.

Maybe in a microscopic way like at quantum level

So what? I'm assuming that some people have some models of physics based on equations, and those don't happen to be of the kind where the state for some t <= T determines the state for t > T. Ok, great - does that predict or explain or simplify anything interesting about the observable universe?

The laws of physics are symmetric in time in classical Newtonian mechanics already. E.g. a swinging pendulum looks the same in time, forward and backward.

What's not symmetric is in the area of thermodynamics and statistical mechanics; E.g. we never observe shards of glass spontaneously reassembling into a window pane.

Sounds like Rupert Sheldrake[1] is finally getting through to people,

1. [A New Science of Life](https://www.sheldrake.org/books-by-rupert-sheldrake/a-new-sc...)

If time were symmetric, wouldn't that mean instead of causality (future is influenced by the past) and retrocausality (past is influenced by the future), there is no preference and in effect no causality at all? A&B are necessarily connected, but none of them is the cause of the other.

If you think of it as a series of states with some prior probability, and jumps from state to state also have some probability, it isn't so much causal as correlated.

If time is a true dimension and reality is the most probable universe when integrated over all of time, improbable states and transitions might occur in the "past" in order to enable high probability states and transitions in the future.

Been kinda wonderin'bout this.

Human memory is a chemical process driven by entropy ("more or less"?), making it one-way(?), so retrocausal info wouldn't be accessed via any mechanism associated with stored memory.

It's articles like this that make me realize why so many less educated people think that science doesn't have rigor, is close to religion, or can't be trusted. Science authors like this do a disservice to science.

To anyone knowledgable. Are theories of retrocausality also related to:

https://en.wikipedia.org/wiki/One-electron_universe

I'd rather read backreaction. These articles always handwave all the actual relevant stuff and give poor pop sci analogies that aren't helpful or accurate

Would this put concepts from classical philosophy like formal and final causation back on the table? The article seems to imply that it’s possible, but I’ve learned that journalistic summaries can be low-fidelity.

The end is not unlike the beginning, in that it has been written to exactitude. “The pen has been lifted and the ink is dried”.

Side note: does anyone remember when Vice was “fringe” in its content? I mean, ten or so years ago…

The first time somebody showed me an article in Vice it was ~2010 and the article was about the style and fashion of how bricks of heroine were being branded. so ... yeah.

Intuitively… we can’t even do science without a notion of time that advances. How can we make observations without there being a concept of “something happened previously”?

I think this is embedded in science itself.

A growing number of scientists recently watched 'Tenet'.

This is 'What the Bleep!?: Down the Rabbit Hole' all over again. Just because something happens in Quantum Physics doesn't mean humans can influence their pasts.

I am fascinated by physics but my original background is math. This all seems fascinating but also sort of baroque and far from experiments like much of QM and GR lately.

Where can I read a more scientific treatment of this topic?

I just need retrocausal information on the stock market, world events, and any threats to myself or my monopoly on retrocausal information access. That's all.

If the information is truly retrocausal you won't be able to leverage it to alter the future :'(.

Perfect response for the subject being discussed -and- your user name -and- a summary of your namesake from of a couple of amazing books by Charles Stross.

I applaud You.

https://en.m.wikipedia.org/wiki/Singularity_Sky

Mandela effect moment

The past is not so much more knowable than the future. the future is about as predictable as the past is knowable.

I try to tell my 'past' self events that have occurred.

I also try to listen to any future 'self' notifications.

It's mostly a fun thought experiment.

Cause-precedes-effect, meet retrocausality. FTL FTW! Oops a new science fiction trope.

The Wheel of Time turns, and Ages come and pass...

while I might buy that the past is strongly influenced by the present (“facts” change over time), I don’t think we have much of a model for the future to say much of anything about how it influences the past.

Or, I guess the point is, maybe it’s the same thing.

I used to believe that the world is lazily loaded. That means the first moment I see something (e.g., a world map) is the point where all the past history to consistently explain the observation gets "locked in".

What changed?

That's still lazy loading, he hasn't looked into it yet.

I feel like this assumes solipsism.

Multiplayer solipsism. That part of the game doesn't load until at least one player observes it.

Wave function collapse in effect?

Was coming to say something like this. Gets to some fun conclusions - ex. paleontologists invent dinosaurs by looking for them.

Another angle on it would be showing that the universe has multiple possible levels of detail - that objects behave like newtonian point masses most of the time, that digestion is replaced by a simple hunger meter when nobody's paying attention.

From this direction, time's main function is compressing "now" so there's more space for something else later.

I'd be willing to believe that everyone has a god-given amount of universe rendering time that can be allocated in different ways, and that other people's attention stacks with it in a complex, layered way.

That would also mean that when I don't see or hear other people, they don't "exist" as physical things that can be seen or heard until I encounter a situation in which they would be.

It's the same as "If a tree falls in the forest and nobody is around to hear it, does it make a sound?"

But then again, that information has to be stored somewhere right?

Like, if a tree falls in the woods and nobody is around, sure you can say it isn't being perceived so it won't be "rendered" but the moment someone walks in the forest and sees that fallen tree, it would need to be rendered from some information about the fall and information of how it looked before the fall. That information would have to be sitting somewhere in limbo waiting to be rendered. So why not just actually let it sit IN the rendered "realm" and now you have one place for data to live in. You save on data transfer fees too.

> But then again, that information has to be stored somewhere right?

As a collection of probabilities stored as a wave.

If a bank account has a 50% probability earning a penny every second, the bank doesn't need to store all of the intermediate values for every "clock tick", but instead calculate how much has accumulated since the last time someone checked the account and store that value with a timestamp.

Where is this wave stored though? And what is the wave made of? A wave of what?

The idea is that the universe "cheats" by replacing a computationally expensive process (a tree falling, breaking into pieces, being eaten by insects, moss growing) with a series of cheaper, "good-enough" replacements, based on the level of scrutiny.

Not existing is the cheapest.

Then, broad strokes, location and orientation

Then pieces, level of decay

etc,

and moving between the layers is you spending your attention budget to force the universe to do more work.

At that point, the least amount of work would be to flip the various chemical and neural vitamin my brain to make me think there is a tree there.

This thought experiment implies that humans, or conscious agents, represent a highly concentrated source of entropy, currently (mostly) confined to planet Earth. Meanwhile, in the vastness of space, most of the mass has settled into some relatively deterministic equilibria, with no conscious agents to alter the course of its future. Yet we're down here on the blue planet messing everything up.

Coupling this thought with the simulation theory, it makes me wonder how the simulation would respond to increasing entropy over a larger volume than just our local system. That is, if we send a bunch of biological/artificial agents in all directions throughout the cosmos and let them wreak havoc, would it crash the simulation? Or what if we just smash a bunch of asteroids out of their stable orbits and let their disruption cascade throughout the system? Or maybe we've already messed everything up by broadcasting highly entropic radio waves throughout a spherical volume with a radius of ~100 light years?

My guess is it would conserve entropy/processing on Earth to match the increased cost.

But there's a difference between "screaming into the void", like broadcasting radio waves, that presumably have 0 effects, and other things.

0 effects on what? For whose benefit is this simulation? The thought experiment implicitly privileges the observer.

》 ex. paleontologists invent dinosaurs by looking for them.

I have seen creationists in web forums trot this exact argument out (only the creator was God of course).

'the world' vs 'my world' and 'your world'

That was proven not to be the case:

https://www.scientificamerican.com/article/the-universe-is-n...

Sounds like that link supports the idea?

Only if you didn't read the article, though I agree that the scientists' choice of terminology is confusing for regular people.

"Manifesting" -- maybe those girls that are into it, are right ;)

World-line travel my friend

https://metallicman.com/detailed-breakdown-of-consciousness-...

For this community it might be useful to stress that the vast majority of practicing theoretical physicists is not in the least worried about any interpretation of quantum mechanics.

I would argue that the idea instead is to try to make predictions for future experiments. In the case of quantum gravity, especially string theory, these might be thought experiments (what happens if you fall into a black hole), technically infeasible experiments (what would a particle accelerator with the size of the solar system produce), or even completely hypothetical (what if the universe would have eleven macroscopic dimensions) but that does not change the underlying mindset.

When it comes to the interpretation of quantum mechanics there is just nothing left to explain. There is no experiment that decides between different interpretations, so that is it as far as most physicists are concerned.

The ideas in the linked article suffer from the same fate: there does not seem to be even a hypothetical way to test them, and the topic is therefore considered one of philosophy more than physics.

Still, can't alternative formulations inspire new physics? Like Lagrangian/Hamiltonian formulations of classical mechanics making the step towards QM easier?

Very tangentially related, but we rewrite the past all the time.

Wouldn’t that be a matter of perception and written history rather than the factual past?

Maybe perception IS reality.

Thats pretty dangerous thinking though. Adolf Hitler famously said "a lie told often enough eventually becomes the truth" and then used that way of thinking to commit horrible atrocities.

What is the factual past?

It's the extrapolation of models that we've created in the present, but those models are only our best guess at the truth. They may be revised in the future or simply not hold for the past.

What? No. The factual past is what actually happened. Don't mistake the map for the territory.

Can you point us to The Territory please? You see it, I presume?

My eyes are a fairly reliable map, but they're still not the territory. That we are only able to perceive reality by proxy doesn't mean that it doesn't exist, though, it just means that we have to get used to using maps, while remembering that they can be flawed.

> My eyes are a fairly reliable map, but they're still not the territory.

This seems.....paradoxical...ironic?

> That we are only able to perceive reality by proxy doesn't mean that it doesn't exist, though....

True, but potentially misleading/misinformative.

> ...it just means that...

Are you sure? Are you referring to the territory here, or the map?

>...we have to get used to using maps, while remembering that they can be flawed.

We've been using maps since the dawn of man, and a lot of people have substantial, abstract knowledge that this is what we're doing....and yet, look at the mess all around us, and the conversations we have about that mess (though: during these conversations, are the participants discussing the map, or the territory: a) in fact? b) in perception?).

The factual past is what actually happened, history is what we wrote down.

Perception and reality are not in fact the same thing.

To be fair there is some disagreement over what exactly "the past" _is_. https://www.youtube.com/watch?v=GwzN5YwMzv0 discusses this a bit.

Can you show that there is a factual past without parsing it through your perception?

It was factual that the earth was 6000 years old, until it wasn't.

> It was factual that the earth was 6000 years old, until it wasn't.

This is the opposite of the example you seem to think it is. The Earth has always had the same actual date of origin. If it is not factual now that the Earth is 6,000 years old, then it wasn't before either. The whole argument here is that people's perceptions and reality can in fact be different.

> The Earth has always had the same actual date of origin.

Maybe, but I'm asking: can you show that peoples' perceptions match/differ from reality, without relying on perceptions being factual/reliable?

If not, then how do you know that reality is fixed?

I would argue that factual past is unprovable without some sort of visual evidence, and even that can be manipulated...especially with AI on the rise. The problem with your point is that EVERYTHING is parsed through your perception, and you can just as easily make the point with the same logic that you can't prove that what you are currently experiencing is present reality.

What actually happened is unprovable without some layer of trust once the event leaves the affected. For example, I ate a grapefruit for breakfast. That is a fact. However, I have tossed the peel away and I am communicating that I ate it with a stranger over the internet. For all you know, I could have eaten cookie crisp. If you and enough people get together and collectively believe that I ate cookie crisp, the public belief will be that I ate cookie crisp. However, that does not change the fact that I ate a grapefruit.

Given that people can hallucinate/make up false memories, you sure you ate a grapefruit for breakfast?

So sure that regardless of what evidence you are presented, you'd be certain that you ate a grapefruit. Even if:

- I showed you videoproof that you were eating a sandwich for breakfast

- we had all of your family say they were having breakfast with you and saw you eating a sandwich

- a doctor came and said "I analyzed your stool and found no evidence of grapefruit"

- we had a message, cryptographically signed by a key you generated/controlled, that said "man this sandwich is delicious"

Even with any amount of evidence to the contrary, you'd still believe that you ate a grapefruit?

If not, then are you sure that it's fact that you ate a grapefruit, or it's just that all current evidence points to you eating a grapefruit?

Given that, there are two, and only two possibilities:

Either

-my perception of reality is inherently opposed to objective reality

-the world, for some reason, is gaslighting me into thinking I ate a sandwich and the objective reality is that I ate a grapefruit.

See, my problem with this "philosophy" that objective reality does not exist is that it enables abusers. Have you ever seen the movie Gaslight? Its a classic. This poor woman lives with an abuser...someone who is committed to making her think that she is crazy. He contradicts everything she does and says, sets up evidence to objectively prove that she only imagined herself doing it, and keeps her under his thumb through those means. In the end of the movie, its revealed that none of the evidence is real and that she is sane. To combat against these types of people, its important to be sure of your own reality and only change if evidence is overwhelmingly pointed in the opposite direction. Even then, question these changes in belief heavily. Otherwise, you will believe just about anything anyone says.

No, that was never factual. Radiocarbon dating gives us evidence, factual without the lense of perception or opinion. Saying the earth is 6000 years old is just repeating propaganda.

Let’s say that you are convicted as a criminal, and allegedly you were in a certain location and committed the crime.

If you were not there and didn’t not commit the crime, is that past to which used to determine your conviction factual?

Whether later you are proven not guilty, the past didn’t change, but rather our perception of it.

You're begging the question. You started with: assume there is a factual past of where you were. And then argued: there is a factual past.

I'm not enough of a skeptic to say "don't trust the models of the past"; memory turns out to be a pretty good model. So does carbon dating.

But the reason you say "you were not there and did not commit the crime" is because you don't remember being there. Maybe you even remember being elsewhere. But that doesn't mean it's true, memory is fallible.

You might say that you even have photos of yourself somewhere else at the time. But if there were photos of you at the crime scene, would that change what the past was? Maybe your memory is shoddy, or maybe the photos are fake.

but what is the metric signature???

In philosophy this idea is called "hyperstition"

>A growing number of scientists are convinced the future influences the past

A growing number of people in general are becoming more superstitious, and more easily convinced of even more incredible occurrences.

Isn't it just a matter of perspective/terminology?

If in my physics theory I redefine that past=future and future=past then I have a physics theory where the future influences the past, and very strongly so.

Alfred Adler would agree with retrocausality.

This would perfectly explain deja vu.

So it goes.

Spooky action at an instance

on the quantum level sure, but on the macro level it's just idealism

This idea is present in several Star Trek episodes. The meta question is when did we create those episodes?

I misread your username as a timestamp and was very, very confused for a minute. Very appropriate in this context.

Well... yes.

http://gurdjiefffourthway.org/pdf/GURDJIEFF%20AND%20TIME.pdf

Thanks Vice

If only physicists were a bit more curious about philosophy…

It's a good idea, but how could they be, in fact?

Why not? What do you mean?

The complaint (a very valid and important one, imho) is that physicists are ~inadequately curious about philosophy - this is the current state of affairs.

To make this no longer be (at some point in the future) the state of affairs, how could it be done (make it "in fact")?

"Why not?" seems like a decent first attack to the problem - why are physicists (or, scientists in general) so bad at philosophy? For one, I would nominate the "When you have a powerful hammer, everything looks like a nail" psychological phenomenon, as one plausible part of the puzzle.

“Everything looks like a nail” strikes me as an accurate description. Dominance of natural sciences provides this philosophical bias towards physicalistic monism, and physicalism in turn limits how those sciences evolve.

I asked ChatGPT if it has any technological applications. No ideas if its just bullshitting

Retrocausality, or the idea that events in the future can influence events in the past, is a concept that challenges our conventional understanding of time and causality. Although it is an intriguing concept that arises in some interpretations of quantum mechanics, it is important to note that there is currently no experimental evidence supporting retrocausality.

As a result, it is difficult to predict how retrocausality could be influenced or used in technology, since we have no concrete examples of retrocausality occurring in the physical world. However, we can speculate on how such technology might work if retrocausality were indeed possible.

    Communication: If retrocausality were real, it could potentially be harnessed for faster-than-light communication or even communication with the past. Such technology might allow us to send messages or information backward in time, which could have a significant impact on how we understand and interact with our own history.

    Computing: Retrocausal computing could theoretically be used to perform complex calculations more efficiently by taking advantage of future outcomes or solutions to influence the computational process in the past.

    Energy production: If retrocausality could be controlled, it might be possible to harness energy from future states of a system and use it to power devices or processes in the past.

However, it is important to reiterate that these applications are purely speculative and based on the assumption that retrocausality is a real phenomenon. Until there is experimental evidence supporting retrocausality or a more comprehensive understanding of how it might work, it is unlikely that we will see any practical technologies utilizing this concept.

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