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Reality as a Vector in Hilbert Space

arxiv.org

21–30 of 51 posts

Re: Reality as a Vector in Hilbert Space

#22

This is idealism getting lost in the sauce to the highest degree. If you ever find yourself thinking "reality is just math", you must remember: the map is not the territory .

I may be risking sounding like a fool here, but isn't there kind of a real distinction between saying that there are underlying mathematical patterns in a reality that behaves like a state machine, and saying that literally this function and starting condition are isomorphic to the universe?

Like if on a low level it turns out that everything is, I don't know, cellular-automata-based, that would be a more useful frame than wandering vectors in a Hilbert space. But if we get to the end of physics and found that, in fact, you could rederive everything from that one explanation, it wouldn't be unfair to say that the universe is that vector, and perhaps some functions.

I guess really I'm wondering if it matters more how the universe is 'computed' or what it's 'computed on'. In a non-simulated universe, of which it seems there must exist at least one, there would at some point just have to be laws without causes. If those laws corresponded to some simple bit of math, it wouldn't be wrong to merge map and territory.

edit: That's not to say that I actually think the paper is correct. I'm definitely not far enough along in my education to be 100% sure, but there are enough suspicious features and a high enough bar that I'm doubtful. I just meant to mount a general defense of 'what if it's all math' type explanations.

Re: Reality as a Vector in Hilbert Space

#23

This is idealism getting lost in the sauce to the highest degree. If you ever find yourself thinking "reality is just math", you must remember: the map is not the territory .

Right, but his whole point is to defend the idea of saying, "what if the math is the reality, what happens then?" It's sort of the same jump that pushed QM forward in the first place of discarding all the assumptions about particles and orbits and just went purely to what was necessary directly in the math.

In the paper he advocates going farther and saying, there's no independent "space" just the vector and space(time) emerges purely from the evolution of that vector.

If your territory is a map, then the map might be the territory.

Re: Reality as a Vector in Hilbert Space

#25
I make my experimental apparatus. I send an electron through a double slit. Hilbert space tells me it goes through both, and keeps going through both for all eternity. I only see one flash. The whole of the electron is found to have hit that part of the screen, and nowhere else. This interpretation just kicks the can down the road, to the "emergence of consciousness", in order to explain simple experimental results.

Re: Reality as a Vector in Hilbert Space

#27
post #23

This is idealism getting lost in the sauce to the highest degree. If you ever find yourself thinking "reality is just math", you must remember: the map is not the territory .

Right, but his whole point is to defend the idea of saying, "what if the math is the reality, what happens then?" It's sort of the same jump that pushed QM forward in the first place of discarding all the assumptions about particles and orbits and just went purely to what was necessary directly in the math. In the paper he advocates going farther and saying, there's no independent "space" just the vector and space(ti…

>what if the math is the reality, what happens then?

Magic. Reversing the relationship between reality and our interpretation of it literally means bending reality with ideas. In this case magic is matrix multiplication.

Re: Reality as a Vector in Hilbert Space

#28

This is idealism getting lost in the sauce to the highest degree. If you ever find yourself thinking "reality is just math", you must remember: the map is not the territory .

Sure, but I think the analogy breaks down in this case.Here the map contains precisely the same amount of information as the territory, no reduction of dimensionality,no loss of resolution. Everything that can be said of the territory can be said of the map and we're left with a case in which the only unique non-shared property of the territory is "physical existence", whatever that is.

Re: Reality as a Vector in Hilbert Space

#29

This is idealism getting lost in the sauce to the highest degree. If you ever find yourself thinking "reality is just math", you must remember: the map is not the territory .

You should read Anathem or Permutation City some time.

I have read Anathem. It's math as occult magic riffing on harry potter.

Re: Reality as a Vector in Hilbert Space

#30
The author is https://en.wikipedia.org/wiki/Sean_M._Carroll

Shortly after Covid19 started last year, he started a series of videos called "The Biggest Ideas in the Universe", playlist here: https://www.youtube.com/watch?v=HI09kat_GeI&list=PLrxfgDEc2N...

I've watched quite a lot of this so-called 'popular' hard science material on youtube, and this series was by far the best I've run across. His approach is a bit different from most others, and his presentation is engaging, approachable but also fairly substantial. Specifically, he doesn't elide all of the relevant math, but doesn't get too deep at the same time. You'll see a lot of integrals, derivatives and graphs.

For example, he talks about an hour on the big idea of 'Change', and another "Space".

Perhaps even more interesting are the followup Q&A videos, which are as long as and perhaps even more detailed than the source.

Do give the linked six minute intro video a watch.

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