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Comment by witheld | Hacker News Reader

It’s a pipe dream, we’ve never done anything that isn’t pretty much observed in nature.

Electricity is observable in lightning bolts, nuclear fission is in the stars, birds fly without all the extra fuss. There’s not a single hint that we’ll ever do anything extraordinary.

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I get the birds and electricity reference, but nuclear fission? Imagine a mediaeval scholar looking at the stars and thinking "I wonder if we could build a nuclear reactor this way?".

Sometimes we simply don't know that we don't know something. It is not enough that something can be observed in the nature, we also need to be able to see it. Currently, we don't see any evidence that faster-than-light travel (or bending space, if you wish) is possible, but we might just not be seeing it.

You should look into the context of other things that was pretty much discovered by luck. Becquerel found something weird with Uranium and Curie found few other materials with radioactive properties without having any sort of theories or prediction at that time.

The question is that if radioactive elements were not naturally present in Earth, would we have known they exist?

That's true, and you can make an argument that we could theoretically find a new kind of substance which then sidesteps all physical limitations known to man. But that's in my opinion as convincing as saying we'll discover magic and go explore the metaverse with it.

> I get the birds and electricity reference, but nuclear fission?

That was fusion, but you can look into natural nuclear reactors (I think first discovered in Gabon) for the fission.

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

> The conditions under which a natural nuclear reactor could exist had been predicted in 1956 by Paul Kazuo Kuroda.[1] The phenomenon was discovered in 1972 in Oklo, Gabon by French physicist Francis Perrin under conditions very similar to what was predicted.

So not only did we not learn by observing the natural phenomena in this case, we actually predicted it (accurately, it seems).

I think the thesis being debated in this thread is the possibility of learning based on observation. No one was claiming that all discoveries were actually made this way.

There’s still consciousness left in the space of things we can easily observe on nature but can’t yet explain.

Going from "we can't explain it" to "might be new Physics" is quite a stretch.

When doing path integrals for predicting particle interactions, we have to consider ALL possible paths and QED matches very, very well its predictions. So any new force has to either require huge amounts of energy or interact very, very rarely.

So in a nutshell, you'll have to explain how this fifth force of nature powering consciousness in our brain fits with this understanding. Given that we know consciousness can be altered or turned off by drugs, and that it is linked to the chemical and biological processes of life, it's very hard to justify the invocation of whole new Physics to explain it.

While obvious, it never occurred to me to argue that we probably don’t need new physics to explain consciousness in this manner. Thanks for that!

Consciousness plausibly plays a substantial role in causality though, something that was being discussed higher in the thread.

There's nothing about consciousness that even suggests that it might break causality - it's as bound by causality as everything else.

>> There’s still consciousness left in the space of things we can easily observe on nature but can’t yet explain.

> When doing path integrals for predicting particle interactions, we have to consider ALL possible paths and QED matches very, very well its predictions. So any new force has to either require huge amounts of energy or interact very, very rarely.

Is consciousness, and the causal role that it plays in reality, fully understood by QED theory? It has high predictive power of future states in a system where consciousness is present?

I see elsewhere you deploy:

> Honestly, it just sounds like human exceptionalism and God of the gaps all over again. I find it pretty hard to justify "we don't know exactly therefore I can invoke magic".

This is a rhetorical technique that can be used in both directions, it would be not difficult to put silly words into your mouth also - the neat thing about reality is that it fully supports describing and perceiving it other than it really is. Typically, people tend to dislike when others do this (if they describe it in a way inconsistent with how they experience it), but enjoy doing it themselves.

> any new force has to either require huge amounts of energy or interact very, very rarely.

That or it completely breaks the rules of physics as we know it. Given that physics has zero explanation for consciousness that hardy seems unlikely.

We can't explain it, but we do have some constraints: consciousness acts on the physical world and is definitely affected very directly by it. At some point it has to interact with the plain old boring Physics governing literally everything about our neurons and our bodies. And yeah, it's hard to explain how our puny brains can interact with this mysterious non-Standard-Model-Physics while particle accelerators, cosmic rays and neutron stars cannot.

Honestly, it just sounds like human exceptionalism and God of the gaps all over again. I find it pretty hard to justify "we don't know exactly therefore I can invoke magic". And not that I'm particularly skilled in philosophy, but AFAIK even Descartes wasn't able to go too far with dualism (which seems to be what you're arguing for).

In nature, we observe the distance between two galaxies increasing faster than light, the intervening space increasing in size without their speed increasing.

Since the distance between two galaxies isn't made of stuff, it's allowed to 'expand faster than light'. There's other examples of the same thing, and we know how to do it. But it can't be used for anything useful.

If you point a light at the moon, and slide your hand in front of the light, the shadow can also "move" faster than light accross the surface of the moon. But the shadow isn't an object that moves to the side, it's really many lightwaves moving forwards (or their absence), so again there's no real thing moving faster than c that could transmit information.

Some materials can be made to have an index of refraction below 1, so that light's phase velocity becomes 'faster than light' (while the group velocity, which is the speed of light, remains the speed of light).

So you can end up with speed values in nature above c, but in all those cases it's not matter or information, so you can't move anything tangible faster than light.

You can see that as an outside-the-box where things move faster than light, and that's fine, but these can never be used to go back inside the box with some real thing that has moved faster than light. That'd break the box, and so any outside-the-box you create can't be usedul inside

Yeah but that's in hindsight though. There are many things that were theorized before to exist based on new physics without direct observations already been made, after which a search confirmed there existence (e.g. black holes). That basically expanded our understanding/knowledge of nature.

I don't know. No other animal figured X-rays. Or neutrinos. There were (are?) things to be discovered only by going as anal as humanely possible at probing reality.

Leaving the pull of earth’s gravity is not observed in nature (except for hydrogen/helium and maybe rocks from a huge volcanic event).

Technically correct is best kind of correct.

It’s observed when asteroid or comet that is flying by does gravitationally assisted change of trajectory.

You know, I've never observed one of those. Have you?

He is technically correct though and that is indeed the best kind of correct.

Disclaimer: Non-Educated Delinquent asking...

I presume String Theory has not been observered yet, thus it remains a theory?

You don't observe a theory. You build an experiment which will either confirm or discard (falsify) the theory, and observe its outcome. The theory remains a theory even in the positive outcome, for it can still be further falsified by other experiments.

(and yes it is impossible to build an experiment for string theory so far with energy levels humanity possesses)

No experiment that could test what is called string theory is known of. So, it is still a speculation, not properly a theory. But it is an extraordinarily detailed speculation. Progress is measured by discovering details that imply or contradict current theory, relying on the "correspondence principle".

If tests for it are ever devised, and it survives, it will be a "Grand Unified Theory" that encompasses general relativity and quantum mechanics, the way those do Newtonian mechanics. Theory is the end state, not the beginning.

In between speculation and theory is hypothesis, a treatment of actual evidence that does not fit into, or anyway is not covered by, the currently favored theory, which has come to be called the Standard Model. This has happened in quantum physics many times, and the theory ends up altered to fit, getting a little more complicated each time. It has lately been hard to find anything new that the Standard Model doesn't get right. Lately, people complain that its numbers are arbitrary and not esthetically pleasing.

But the Standard Model has long been known to be incompatible with General Relativity. So far we have not found cracks in either one. Chances are it will be centuries before we could properly test a grand synthesis, if we could invent one. "String theory" might hold the outlines of such a synthesis, or might be just a mathematical oddity with curiously physical qualities, a model of a possible universe that does not happen to match ours. Even our great-grandchildren will most likely never know.

It is false. There are parts of mathematics that have no known application to physics.

Comment doesn't say there are, or was it edited?

There are hints that some things exist in more than four dimensions, but that's it. There is no hint that we could apply it to any technology.

Definitely not now or anywhere in near future. But just imagine that there might be something out that even the smartests of the smartests couldn't have imagined until now.

While I don't remotely know what it would be like, I definitely know that there's so much we don't know and have not discovered yet.

Having not even found out secrets about our own planet's oceans, Fermi Paradox, or origin of consciousness/life/death, I'd say there's still much to be discovered in physics.

For what it's worth, I agree with you that something may be discovered some day.

But we currently have absolutely no evidence nor hints that might happen. We actually have more indication that an almighty creator exists than we have indication that humans may someday achieve FTL travel. At least the former has eye-witness testimony spanning hundreds of documented cases across centuries and cultures. FTL travel? Just speculation and Gene Roddenberry.

> more indication that an almighty creator exists

Has that ever not been the case? God has been the goto explanation of anything modern humans didn't understand.

The most brilliant minds at various points couldn't have thought "aye, if we cut a tiny thing inside a metal heavier than lead or glue these tiny things inside air it can create more energy than lighting/gunpowder/dynamite".

Or that wireless communication is possible and sending a manmade moon out around the Earth is also possible, and you can do both for instantly sending light signals, nay, whole books around the globe.

Or virtual worlds that are not bound by any physics (maybe we're dumped into one at birth which can make any observations rather pointless heh).

I can't imagine FTL (although far out theories exist), but our current method of choice is chemical explosions, so there's some massive improvements to be made there.

It is true that evidence for the Almighty is falling, one stick at a time, with many clinging to what remains, but the endpoint is clear. Of all of it, the sense that there is more to the universe than we will ever perceive would be a true loss, if it goes too.

>Definitely not now or anywhere in near future. But just imagine that there might be something out that even the smartests of the smartests couldn't have imagined until now.

Yes, sure, that's always possible but it's not reasonable to take that and then say "therefore maybe X". Maybe fairies. It's not a way to get to any particular conclusion.

But still, FTL travel is not possible in the Universe *with our current understanding of the Universe and its physics*. Maybe it will stay forever like that, or maybe not.

Yes of course, maybe, but we can't say that this is particularly probable and that disbelieving it is laughable, as OP claimed.

Maybe faster than light travel is clearly observable in dark matter or quantum entanglement

What about:

The wheel

Plastics

Internet

Memes

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