The Grand Illusion: Does time have a future? | Hacker News Reader

The Grand Illusion: Does time have a future?

laphamsquarterly.org

61 pointsbenbreen43 comments

The philosophy of time is one of the remaining bulwarks of a philosophical position called 'dualism', which holds that minds are completely separate from our bodies: if you view us as being big ropes of particle-worldlines in a 4-dimensional fixed universe, you are basically stuck with describing us as "souls" who have latched onto this rope and are traveling along it, living the experience even though the future is as set in stone as the past. It makes relativity really easy to understand, but it makes entropy comparably harder (since the premise of entropy is that our uncertainties multiply due to particle collisions until things end up in more and more uncertain states). It almost sounds like there's no free will in this perspective, but that's not quite true. Instead you get a model of free will which is a lot like you see in the movie The Matrix: "Because you didn't come here to make the choice, you've already made it. You're here to try to understand why you made it."

Relativity does not necessarily compel this. It is true, the relativistic "present" is a space between two light cones, and not just one plane. But that's not necessarily a huge obstacle: we can just pretend that there is one plane which is the "true present" and accept that the laws of physics make it impossible to know if we're truly right about which it is. As long as one of the planes is the true present you can lift up the Newtonian way of looking at time to the special-relativistic whole.

It turns out that black holes aren't really so interesting as this article claims, because there is a 'co-moving' metric which falls into the black hole's event horizon in a finite time. What happens with a black hole is, you see someone slow down more and more to a standstill as they approach the event horizon, appearing to "merge in" with that surface, redshifting into the quantum noise of the Hawking radiation there. But from their perspective, you're just seeing their "last moment in this universe"; they'll keep going on past that horizon.

But general relativity is still a problem. It describes the causal fabric of the universe as warped by the energies that inhabit each part of that fabric, and that makes it really hard to deal with time. Some of the interesting stuff here comes either from (a) alternative descriptions of relativity (like spinors/twistors, where you describe the entire world-line of a particle as a point), or (b) quantum mechanics (where you can do multiple-universe-splitting). The combination of relativity and quantum mechanics, for example, seems to give us the Wheeler-de Witt equation, which time famously "falls out" of (it plays no final role in the equation). Some physicists, notably Julian Barbour, think that this means we've got to fixate on a static universe. I'm totally undecided on this but I find it fascinating.

>The philosophy of time is one of the remaining bulwarks of a philosophical position called 'dualism', which holds that minds are completely separate from our bodies

Whose mind? Would you say that the mind of a worm is separate from its body? Suppose - no. Then where does mind gets separates from the body - at ant level? at fish level? at lizard? at mammal? at ape? at Neanderthal? at Cro-Magnon 20K years ago?

Mind is just an emergent behavior of a pretty complex organized matter. The more complex the matter the more its ability to increase entropy beyond simple local gradient and that ability is what we call mind.

"Free will" is just a part of that "mind". The obvious question here again - does a worm has free will?

In general these notions of separate mind or especially soul are misconceptions coming from religion where world was created 6 thousands years ago with God giving soul to humans only and with no continuous biological connection between first living cells couple billion years ago and humans today.

These "misconceptions" don't come from religion. That's a huge strawman, as if you have to believe in a Great Flood to be curious about the nature of consciousness, beyond declaring it a property of entropy as if that answers anything at all.

Video game enemies have a "Mind" they can make predictions, plan, and with reasonable levels of AI even learn. But, we understand what's going on which "Kills" any meaningful debate. Not really understaniding cellular biology and the emergent behavior of the human brain is no reason to assume anything odd is going on either.

PS: Ok, there is a reasonable question of how good an AI needs to be before killing it is wrong.

So if you were programmed to say this, where and how did the original program originate?

That's not an answerable question. Making it meaningless. Which electron in you left ear had the lowest energy over the last second?

PS: This is actually a trick question as the frame of reference is important.

I do not agree at all. I think that there must be one (or a few) simplest possible computing systems and that it would be both informational and interesting to figure out the basis upon which biological computing is premised.

There are lot's of simple computing systems, knowing about them tells you nothing about biological computing. (ED: Sort of, there are classes of computing systems and understanding their limitations has some value.) If for no other reason than the fact you can generally simulate X computing system in Y and Y computing system in X.

Let's take a step back and look at flight a much 'simpler' system that we 'know' a lot about. First we looked at birds and insects and thought this is possible.

You can get a fairly simple model of how wings work that's good enough to build a basic glider. It's wrong, a much better approximation let's you build high efficiency sub sonic jet's. Crossing the sound barrier demonstrates flaws, but we have yet more models for that. A particle model of an aircraft based on Newtonian physics is even better and avoids those wacky approximations. Unfortunately it's way to complex to use and even worse Newtonian physics is also wrong. QM is better still, but also wrong. A mix of QM and General relativity is the best we have, but again it's wrong.

Where was I going with that line of thinking? We might be lucky enough to find a model that's indistinguishable from reality. That does not mean it's useful or even correct. And just because we build something that thinks (fly's) that does not mean it's got much to do with how we think (or birds fly).

PS: This might all seem pedantic. But, asking how something works is not an answerable question. Asking for a model of how something works is. But, useful model's often have little to do with reality. (ex: epicycles can approximate any curved orbit to any precision given enough of them. http://en.wikipedia.org/wiki/Deferent_and_epicycle They where effectively taking a Fourier transform of the orbits.)

Like all seemingly designed properties of living things, they came about through a process of evolution.

I urge you to re-read the post you're replying to, since it's actually a lot more complicated than you think.

- There's nothing even ~close~ to neurobiological evidence for subjective experience - Nothing has changed in 6 thousand years, we know as much about god, time, and subjectivity as we do today

You ~think~ that dualism is impossible but you don't understand monism.

At the full blown materialist end there's another big problem though: Are you just a cloud of ever changing atoms mistaken for a person? Since almost none of the atoms from your childhood remain in you now, are you actually the same individual? If yes, by what measure and means? If no, then how can a cloud of atoms have things like "rights", personhood, etc?

In addition to both dualism and materialism there is a third way called Hylomorphism: http://en.wikipedia.org/wiki/Hylomorphism

>Since almost none of the atoms from your childhood remain in you now, are you actually the same individual?

i hoped that not, i hope that i did mature at least a bit :)

But you question i suppose was about a little bit different aspect of "the same" and to that aspect i'll ask you - this river, the set of ever changing atoms of water, is it the same river that it was a second ago, an hour, an year...?

>If no, then how can a cloud of atoms have things like "rights", personhood, etc?

In physics where is no "rights". The "rights" is just a "mind" construct reflecting current balance of violent interactions between different "clouds of ever changing atoms".

I don't think these questions are really very interesting. "When is a day no longer sunny, but cloudy?" There is probably a name for this class of things, where there's some fuzzy-ish boundary. But it seems like s mistake to get caught up in it as if it makes a difference. Sorta like arguing over what life is. Is a plant alive? But plants aren't like animals, so what then?

It actually seems like arguing about definitions.

I have almost no experience with philosophy like this, but somehow have come to a very non-dualistic worldview of my own through a lot of thinking and writing in my personal journal. The whole "universe is a static 4D object" idea. I've never heard of anyone else talk about it before except myself.

Are there any books that you can recommend that delve into the philosophy behind this?

Max Tegmark has some really good writing on this. I quite like the idea that the "universe Hamiltonian" acts deterministic in phase space such that the universe's wave function evolves deterministic. From the "inside" of the system, the atoms in our brain are just carried along on a stochastic path such that the conscious awareness we currently inhabit is one of many the many possible paths through the large phase space. From the "outside" the universe is a infinitely dimensional, phase space that evolves deterministically through time.

That way I reason about it is that the big bang was a single "pixel" of super high energy in an infinitely dimensional phase space and the laws of physics are a Hamiltonian "kernel" that evolves the phase space in a similar way to the heat equation. Thus this kernel acts on the phase space from the big bang, mechanistically acting out the laws of physics, all the way until the heat death of the universe: effectively the fixed-point of the universe kernel.

This may all sound like bullshit to a physicist, but it's the application of my limited understanding of physics and mathematics to the thought experiment.

Good reading here:

http://en.wikipedia.org/wiki/Mathematical_universe_hypothesi...

http://space.mit.edu/home/tegmark/mathematical.html

http://arxiv.org/abs/0704.0646

I recommend "hard problem of consciousness" on wikipedia, I think it's at the core of all arguments against the non-dualistic, materialistic worldview.

I don't think the frozen block view of time necessitates a belief in anything traveling along a world line (how would you express the speed at which it travels?) At any given point on your world line your brain is in some state and your 'mind'/conscious experience at that instant is what it's like to be that state.

The "speed" of consciousness would just be in terms of the subjective rate of experience. But yes, that's a significant problem with appealing to this sort of attitude outside of this 4D world (you have to invent some notion of time which applies to souls but not matter).

It is true that you can "step back" from the world-line and insist that every part of it is conscious, but that takes a really radical position on our own conscious experience of the progression of time, one that's actually distinctively Buddhist, if you can believe it. (There's a lot of Buddhist speculation about how the mind is a series of "aggregates" rather than one temporal whole; the idea is that you are no more identifiable with the you-of-twenty-seconds-ago than a candle's flame as it has exhausted a new quantity of vaporized oil: in a metaphorical sense we say that both "are the same" but we don't really mean much by it.

In general though, saying that "the whole worldline is conscious" abdicates our notion completely that time progresses, and instead says it's all illusory (we have a local sense of progression even though nothing progresses). I think that the reason that this is unpopular is simply because if such an illusion exists, it has an interesting asymmetry with other illusions: you can't actually shake it. (It has some other problems, like: it's hard to see why natural selection would assemble those world-lines into something which have these feelings, given that they don't seem to do anything -- and of course natural selection becomes just a metaphor to describe a pattern in how the lines are structured, rather than a force which changes the world, so it's hard even to phrase the question much less answer it.)

Although I'm a very scientific / sceptical type of person, I've come to the conclusion that dualism is the more correct way to see the world and that something like free will exists. The reason for this belief has more to do with consciousness (see hard problem of consciousness) than time.

For free will to exist, there must be something capable of non-deterministic behavior. In absence of that it seems prudent to view "free will" as a useful but ultimately inaccurate model.

So it's highly suggestive that at its most fundamental, the universe appears to be non-deterministic. No theory predicts exactly when this neutron will decay.

Wouldn't determinism have been "easier?" If there is no free will, non-determinism seems like a lot of trouble to go to for nothing!

(You might be joking, but I'll give my po-faced reaction anyway.)

>Wouldn't determinism have been "easier?"

This question doesn't really have any meaning. Easiness is a concept imagined by humans in the context of our own endeavours. And even if you suppose a sentient creator similar to ourselves, we still have no means to judge what kinds of universes would be easier or harder to create.

I think he/she means "easier to grasp", not to design.

Yes, much like how "atoms" are a useful but ultimately inaccurate (because subatomic physics) model.

Exactly. There are loads of theories and models that are incredibly useful until you look at them from just the right angle and see how weird they really are.

Yes, that's basically what I think actually happens. That physical particles in the brain don't behave according to currently accepted physical model – but the non-physical mind has the ability to "push them". For example, the supposedly random quantum phenomena may not be random but affected by our mind. It probably sounds crazy but I believe there is a reasonable argument backing this. A very brief summary – 1) mind is non-physical (see hard problem of consciousness) but physics can affect the mind 2) and the mind can affect the brain because otherwise I wouldn't be realize that mind is non-physical.

Hard problem of consciousness is no doubt hard. But it seems odd to take that, then jump to a rather unsupported conclusion. Seems a bit reminiscent of people a long time ago not understanding something, then declaring it to be governed by another set of laws.

Well, like I said, it was just a brief summary, point 1) would be much longer if I had time, what I said is basically no or very weak argument.

It seems that 1. the ability of drugs to warp the mind and 2. the ability of researchers to implant memories into the minds of rats by altering proteins both suggest that the mind is a strictly materialistic phenomenon.

What I said is compatible with 1. and 2. Like I said, physics (state of physical particles in the brain) can affect the mind.

What evidence exists that there is more to the mind than "just" physics (which is already pretty cool)?

It seems a jump to say the contents of mind and the awareness of mind are the same thing.

How is that a jump? The contents and behavior of everything else are the same thing. We just think our minds are special because we have no external reference frame. In the absence of evidence to the contrary, the most likely explanation by far is that our minds are vastly complex chemical reactions, computers with some of our outputs connected back to our inputs giving us the illusion of dualistic self awareness.

With as many neurons and synapses as we have, there is more than enough complexity to expect the mind to be purely physical. I don't see why that bothers so many people; I think it's incredibly awesome.

I don't think your second argument necessarily holds.

Is it not possible that the brain simulates the experience of qualia (itself a philosophical zombie) but that this process is what causes the non-physical mind to exist, and to experience those qualia?

I take umbrage with this part: "A past that can be revisited has not really passed. So, Gödel concluded, time does not exist." This is a very silly conclusion. My assumption is that the silliness is attributed more to the author of this article than to Gödel himself.

Our intuitive concept of time from our existence at speeds very slow compared with the speed of light and at masses which are very small when compared to those necessary to bend space-time is not necessarily applicable to time in all regions of this speed-mass phase space. Particularly the regions where the speed is close to the speed of light and the mass is very large. There's just no logical path from the initial observation to the conclusion that time doesn't exist.

I admit I'm well below the mental capacity to confidently state something as bold as "time does not exist", but I'd like to offer my thoughts. When thinking about Schrödinger's cat, [1] I imagined that the cat remained dead (and in every other possible state) even after the observer had confirmed the cat was alive. Every unobserved state did not collapse, but became inaccessible by means currently understood. Those states could still be observed by the same or another observer from a different perspective (i.e. revisiting the event). We just have to figure out how.

[1] http://en.wikipedia.org/wiki/Schrödinger's_cat

I think the idea of time that does not exist, is one that is like a river, that has flowed past and can never be revisited.

I just came up with this stupid theory for the fun of it.

Say time is self contained in the universe, just like all frames in a DVD. The process of going back and forth thru frames is what we call time, you need an observer capable of processing frames as input to produce information from them. Without the information processor, you still could see the universe as a whole (like the DVD) but not be able to see the frames stored in it in a sequencial manner.

The only big difference between a DVD and the universe is that the latter is infinite.

Well forget about it. If everything is self-contained then it gives determinism an upper hand against free will, and I hate determinism.

Perhaps the universe is like a DVD being burned as we speak and free will still reigns?

I said it was all for fun, don't be too hard on me. I always thought time was absolute, and perception was relative. Well, tell that to a god's particle before being created. There is no time in the void.

I kind of enjoy to intellectually "know" (or think I know) that there is no free will -- certainly not to the degree our consciousness often thinks there is -- and still to appreciate and say yes to the illusion. I don't know why, but I still do :) Such is the power of the mind. You can know there is no free will and still believe there is, and you can know that belief to be false and still allow it in, like a dirty old dog you let sleep on the couch because its your favourite dog and you love it deeply. We can do that, and I find that beautiful.

Also, from http://www.einstein-website.de/z_biography/credo.html :

> I do not believe in free will. Schopenhauer's words: 'Man can do what he wants, but he cannot will what he wills,' accompany me in all situations throughout my life and reconcile me with the actions of others, even if they are rather painful to me. This awareness of the lack of free will keeps me from taking myself and my fellow men too seriously as acting and deciding individuals, and from losing my temper.

But I don't like that translation too much, so here is my own very slight variation on it:

> I do not believe in the freedom of the will. Schopenhauer's word: "Man may be able to do, what he wants, but he can't will, what he wants", accompanies me in all situations of life and reconciles me with the deeds of mankind, even though they are quite painful to me. This realization of the unfreedom of the will protects me from taking myself and my fellow human beings all too seriously as acting and judging individuals, and from loosing my good humour.

I feel like the idea that free will is an "illusion" kind of misses the more fundamental realisation of Compatiblism: Will doesn't need to exist as something external to the rules of the universe for it to have meaning.

We might not have "free will" (whatever that means), but we definitely have "will", and that's all that ever mattered.

There is a pretty fascinating Google Talk on this subject by Sean Carroll: https://www.youtube.com/watch?v=GFMfW1jY1xE

Here's my layman hypothesis:

Time has a wave-like nature, not the particles. Since space and time are related through the Lorentz transformations, you could substitute a wave-like property of time and make the time dependent wave equation into a space dependent equation. The results would be the same, but it's a different interpretation. This is why you cannot measure a particles momentum and position at the same moment - they do not both exist at the same moment and depend on the current phase of the wave.

http://blog.rongarret.info/2014/10/parallel-universes-and-ar...

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