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An approach to the fundamental theory of physics

wolframphysics.org

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Re: An approach to the fundamental theory of physics

#61

Post by Jensson »

bowsamic wrote: post #21
andrewflnr wrote: post #19

Earlier quoted context omitted.

Is it just because it hasn't gotten as far as making physical predictions yet? To put it charitably it's very abstract, but I wonder exactly where the holes are that real physicists see.

Physicists won’t take a look at a new theory unless the person pushing it can demonstrate very good reasons for physicists to do so. Generally those have to be quite concrete reasons: for example explaining a known phenomenon in a much clearer or more intuitive way, or allowing the explanation of systems that weren’t easy to conceptualise of before, etc. But ultimately it’s up to Wolfram to come up with those things.…

> Physicists won’t take a look at a new theory unless the person pushing it can demonstrate very good reasons for physicists to do so

So why did all the string theories get popular?

Re: An approach to the fundamental theory of physics

#62

Post by mathinaly »

throwaway81523 wrote: post #49
VirusNewbie wrote: post #38

Earlier quoted context omitted.

>. Turing machines specifically are not required to preserve anything about the initial state and so information can be destroyed and created ex nihilo, violating the main principle of physics which requires that all matter and energy be conserved. The equations have to balance out at the beginning and the end, whatever you start with can not be greater or less than what you end with (at least in physics). can you ex…

I think something like this. Imagine a computer with two memory cells x and y, and a program that maintains the invariant x+y=5. That is information about the program and about the state of the machine: if x=2 then y=3, if x=20 then y=-15, etc. Now replace that program with an arbitrary Turing machine that can do pretty much anything with those memory cells, like set both of them to zero. You no longer have the infor…

That's a good example and demonstration. The unitary invariance basically requires that the norm of the vector is preserved so that if we start with a unit vector then unitary evolution of that vector will always keep it that way. This is not the case for arbitrary programs because they don't have to preserve any invariants which makes them ill-suited for physical theory building. This is why Wolfram's approach is too open-ended, hypergraph evolution is way too lax of a framework for describing physical reality and conforming to existing experimental results.

Re: An approach to the fundamental theory of physics

#63

Post by andrewflnr »

Jensson wrote: post #61
bowsamic wrote: post #21

Earlier quoted context omitted.

Physicists won’t take a look at a new theory unless the person pushing it can demonstrate very good reasons for physicists to do so. Generally those have to be quite concrete reasons: for example explaining a known phenomenon in a much clearer or more intuitive way, or allowing the explanation of systems that weren’t easy to conceptualise of before, etc. But ultimately it’s up to Wolfram to come up with those things.…

> Physicists won’t take a look at a new theory unless the person pushing it can demonstrate very good reasons for physicists to do so So why did all the string theories get popular?

FWIW, by my reading string theory is, incredibly, a lot closer to being testable than this thing, which is more like a proposed formalism in which to expess a theory than a theory itself.

Re: An approach to the fundamental theory of physics

#64

Post by imglorp »

jiggawatts wrote: post #54
throwaway81523 wrote: post #50

Earlier quoted context omitted.

I remember looking at the hypergraph stuff a while back and thinking "this can't possibly handle the double slit experiment". I looked through the different pages and found no references to it. I shrugged and moved on. A few years later another blog post by one of the members went up saying "of course we can explain the double slit experiment, from the beginning. We left it out of the early posts on purpose so someon…

My key threshold is the three particle generations, e.g.: electrons, muons, and tau particles. If your TOE doesn’t even mention them, then that’s a bad sign. Any mention at all will have me sitting up straight and putting my reading glasses on. Wolfram’s theories are so, so far away from this threshold that it’s hard to even explain to non-physicists.

I saw a claim that they had produced GR from their model. Does that count for anything?

Re: An approach to the fundamental theory of physics

#65

Post by jiggawatts »

imglorp wrote: post #64
jiggawatts wrote: post #54

Earlier quoted context omitted.

My key threshold is the three particle generations, e.g.: electrons, muons, and tau particles. If your TOE doesn’t even mention them, then that’s a bad sign. Any mention at all will have me sitting up straight and putting my reading glasses on. Wolfram’s theories are so, so far away from this threshold that it’s hard to even explain to non-physicists.

I saw a claim that they had produced GR from their model. Does that count for anything?

No. That's surprisingly easy[1], and the last time I checked they hadn't reproduced anywhere near the full theory of general relativity. They've just found a thing that suggests that it's possible to map things to a curved spacetime manifold. If I remember correctly, they didn't actually show that this was in any way natural or the only possibility.[2]

[1] There is more than one way to model GR or large subsets of it either mathematically or physically. It sounds like a complex theory but in many ways it is actually "minimal" and highly constrained, making it pop out of unrelated things surprisingly easily. For example, crystal defects moving under thermal vibrations of the lattice can model GR! Similarly, variable index of refraction has very GR-like mathematics and can model everything except torsion (I believe, I'm not an expert).

[2] A key thing with such fundamental theories is not just to show that it can do something in physics but that it cannot do anything else.[2b] Without that constraint, any general computational theory like Turing machines "contains physics". So does the space of all computer programs, lambda calculus, etc... Those aren't useful statements, but that's pretty much what Wolfram's theories boil down to. He keeps finding very simple systems that can compute arbitrary things, pointing at them and exclaiming that "Physics is in there... somewhere!"

[2b] E.g.: Four dimensions of spacetime with a +++- or equivalently a ---+ signature, but not anything else such as ++++ or ++-- or five dimensions. Similarly, three generations of particles, not two or more than three. Etc...

Re: An approach to the fundamental theory of physics

#66

Post by skissane »

mathinaly wrote: post #62
throwaway81523 wrote: post #49

Earlier quoted context omitted.

I think something like this. Imagine a computer with two memory cells x and y, and a program that maintains the invariant x+y=5. That is information about the program and about the state of the machine: if x=2 then y=3, if x=20 then y=-15, etc. Now replace that program with an arbitrary Turing machine that can do pretty much anything with those memory cells, like set both of them to zero. You no longer have the infor…

That's a good example and demonstration. The unitary invariance basically requires that the norm of the vector is preserved so that if we start with a unit vector then unitary evolution of that vector will always keep it that way. This is not the case for arbitrary programs because they don't have to preserve any invariants which makes them ill-suited for physical theory building. This is why Wolfram's approach is to…

I think there is a flaw in your logic here. The physics we know has certain features-e.g. unitary evolution. But, it is possible that there is a “deeper level” of physics we haven’t discovered yet. There are some major proposals for what that “deeper level” (or levels) might look like - e.g. M theory or loop quantum gravity - but for all we know maybe the underlying “real physics” is something nobody has even thought of yet, maybe something completely out of left field whose discovery is centuries away.

Whatever that “deeper level” is, should we assume it shares the “surface level” features such as unitary evolution? Well, there are two possibilities (a) yes it does (absolutely or universally so), or (b) in the most general case, no it doesn’t, but in the normal situation those features emerge.

Suppose, in the “ultimate physics”, unitary evolution is actually violated, but only at very extreme energy levels we are nowhere near being able to test? Or maybe it is conserved locally, but in distant regions of the universe (say a googolplex parsecs away) it isn’t? Or maybe it is conserved in the present, but in the very distant future (say a googolplex years from now) it won’t be any more? Do we have any way of knowing those possibilities won’t turn out to hold?

But if we don’t, then using the fact that cellular automata lack that feature as an argument against Wolfram’s hypothesis - it seems to me rather weak. That’s not to say that his hypothesis is actually true - I’d be rather surprised if it were. But I just don’t think this is a very convincing argument against it

Re: An approach to the fundamental theory of physics

#67

Post by mathinaly »

skissane wrote: post #66
mathinaly wrote: post #62

Earlier quoted context omitted.

That's a good example and demonstration. The unitary invariance basically requires that the norm of the vector is preserved so that if we start with a unit vector then unitary evolution of that vector will always keep it that way. This is not the case for arbitrary programs because they don't have to preserve any invariants which makes them ill-suited for physical theory building. This is why Wolfram's approach is to…

I think there is a flaw in your logic here. The physics we know has certain features-e.g. unitary evolution. But, it is possible that there is a “deeper level” of physics we haven’t discovered yet. There are some major proposals for what that “deeper level” (or levels) might look like - e.g. M theory or loop quantum gravity - but for all we know maybe the underlying “real physics” is something nobody has even thought…

I wasn't providing an argument to convince anyone of anything. Study the mathematics and if you have a way of making progress in constructing better physical theories based on Wolfram's foundations then more power to you. In general, talk is cheap and the proof is in the pudding. Wolfram never provides any testable results of possible experiments to validate his theories. He is mostly theorycrafting with rewrite systems and hoping something useful comes out. It's a lot like an evolutionary search over the space of possible rewrite systems to make some nice looking graphs. Whatever he's doing is not science in any meaningful sense of the word because there are no predictive and falsifiable experiments based on his theories.

Re: An approach to the fundamental theory of physics

#68

Post by mcmoor »

zachf wrote: post #39
sesm wrote: post #4

Earlier quoted context omitted.

It's like string theory - a framework with tons of free parameters which will never produce a coherent physical theory, but you can always write a paper that contains a promise of explaining any observation with the right fine-tuning of some parameters (the promise will never be fulfilled, of course).

There are exactly zero free parameters in string theory [0]. The details of why string phenomenology is hard is a difficult subject, but the characterization you've given of it is not correct. If you have a proof that string theory is not self-consistent, you should publish it, because there is no such proof in the scientific literature today. (Source: my PhD in physics.) Unfortunately, there is a ton of misinformati…

I thought lots of variants of string theory do predict things inside human means. But they've all failed, leaving only variants that predict things outside of it.

Re: An approach to the fundamental theory of physics

#69

Post by bowsamic »

Jensson wrote: post #61
bowsamic wrote: post #21

Earlier quoted context omitted.

Physicists won’t take a look at a new theory unless the person pushing it can demonstrate very good reasons for physicists to do so. Generally those have to be quite concrete reasons: for example explaining a known phenomenon in a much clearer or more intuitive way, or allowing the explanation of systems that weren’t easy to conceptualise of before, etc. But ultimately it’s up to Wolfram to come up with those things.…

> Physicists won’t take a look at a new theory unless the person pushing it can demonstrate very good reasons for physicists to do so So why did all the string theories get popular?

Because it did do those things

Re: An approach to the fundamental theory of physics

#70

Post by Certhas »

thewanderer1983 wrote: post #47
Certhas wrote: post #12

Earlier quoted context omitted.

I used to work close to people who were actually somewhat close to the stuff contained in the papers. The consensus was that there is nothing of substance to engage with. Edit: When the technical papers appeared in 2020, I personally went through them in some detail. Tl;dr there are almost no novel ideas of substance in there. Specifically I looked at the "launch documents" provided here: https://wolframphysics.org/t…

> The consensus was that there is nothing of substance to engage with. The safety boat of scientific consensus is pulled out a lot in today's environment. One should remember that many of our great scientific discoveries had a scientific consensus that it replaced. That boat won't always steer you in the right direction, sometimes you have to read the paper and come to your own conclusion.

What reason do you have to believe that your own conclusion will be better?

The causal set folks are already outsiders that go against the broad consensus of HEP-Th. I grew up scientifically in an environment that was actively challenging mainstream consensus. Sometimes correctly (e.g. low energy susy), sometimes not. If those folk can't find something redeeming in what you do you should stop and listen.

Also, yes scientific consensus at the cutting edge changes over time. That's the nature of science. But I challenge you to find a single example where the consensus was "there is nothing of substance here" and it turned out to be wrong. Not all forms of challenging consensus are equivalent.

At the end of the day though, this is HEP. Itt doesn't matter. Worst that can happen is that you waste your time learning some neat math.

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