An approach to the fundamental theory of physics(wolframphysics.org) |
An approach to the fundamental theory of physics(wolframphysics.org) |
It's a good test for the community whether we can focus on what's new/different/interesting here and resist the temptation to noise.
* (https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...)
I would expect something like "an here is Max Planck Institute for Physics collaborating with Wolfram Physics research project on ...". Or something of that nature. At least after all these years.
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/technical-documents/
which, to my knowledge, still are the closest we have to a coherent description of what the grand vision is. Unfortunately I didn't keep my detailed notes, but looking specifically at the relativistic paper, it might appear substantial, but that is because large parts of it review well-known basic results in discrete geometry and causal sets. The actual content is described in a hand wavy way, with little in calculations or rigor (and some elementary mistakes, too).
The issue is that everything that goes beyond standard results is essentially wishful thinking or circular. "If my update rules are such that they produce a causal structure that corresponds to that of a 4-dimensional spacetime, then the wolfram model produces a 4-dimensional spacetime!". This would be interesting if there was any way to characterize the update rules that do so. However, there is not. There is simply the implication that since update rules are very general it must surely be possible to find one that does. Actually doing so is left as an exercise to the reader.
A prime example is in Section 3.3:
In all that follows, we shall assume one further condition on the hypergraph update rules, beyond mere causal invariance: namely, “asymptotic dimensionality preservation”. Loosely speaking, this means that the dimensionality of the causal graph show converge to some fixed, finite value as the number of updating events grows arbitrarily large.
However, abstractly defining ensembles of causal graphs that actually produce (at least with high likelihood) the causal graphs of low dimensional manifolds is exactly the core of the issue. If you are able to do that, then the standard results of causal set theory get you the rest of the way. This central difficulty is simply "assumed" to be solved. No further discussion is given on what type of update rules would actually be dimensionality preserving, nor is this identified as a key research question, nor is any evidence or heuristic provided that WOlframs approach has anything new to say on this problem.
As far as I recall the quantum mechanics paper was even worse.
I think the above comment perfectly summarises the situation.
There has been a lot of fanfare but no action coming from Wolfram’s research.
It’s even more disconnected from physical reality than the more abstract mathematical corners of string theory.
The hard part of a TOE is showing how it maps to reality, how the theory constrains what we can measure in future experiments, etc… This is the part that Wolfram keeps skipping over.
I’ve had an interest in theories of everything (TOEs) and I’ve read through hundreds of papers from serious publications to gibberish put out by mentally ill cranks. I’ve developed a checklist to filter out the noise. Wolfram’s theories don’t tick any boxes! Even crazy rants on some personal blog written in random fonts with ten text colors do better.
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.
If true, that still seems like something of merit, even if the project doesn’t give any progress in fundamental understanding of physics?
Maybe, rather than as they hope, being a path towards a theory of everything, it could instead be a path towards a framework for understanding good ways to do numerical simulations that respect causality, while not necessarily doing all of one time coordinate everywhere (in some reference frame) before computing later times anywhere?
I think the comment you replied to is asking for groups or individuals of note and independent but working with Wolfram on the merits of his/their research. Your link didn't shed more light I think.
[0]: https://writings.stephenwolfram.com/2020/04/finally-we-may-h...
What's not so present in CS (at least where I studied) is philosophy of science. Falsifiability and how theories are created and tested is less grounded in my mind than the topics already mentioned. Though, in physics, this is really important.
Last time I checked, his approach was not able to make real predictions about our world. So it's not yet a real theory. Of course, this doesn't mean people should stop working on this. It also took humans a long time to develop the mathematics to describe gravity correctly.
https://brilliantlightpower.com/wp-content/uploads/theory/Th...
https://brilliantlightpower.com/subject-exciting-news-the-gr...
Last time I checked, their claim was that the universe can be modelled as a sufficiently large hypergraph rewriting system, with some initial state, and some set of rules. Which initial state? Which set of rules? Well, uh... some!
It's like saying that the Universe can be modelled as a Turing machine, with sufficiently large memory. (or a bunch of pebbles: https://xkcd.com/505/)
Are there any new claims from them?
> The problem with comparisons with Chuck Moore's philosophy of perfection is that we're trying to do things he has no interest in. We're trying to live in the real world. ... for the time being the rest of the world isn't content to tinker tiny programs into perfection in a cabin in the woods, barely able to articulate their value in a universally cogent way.
I'm not trying to stir the pot or create infighting on HN, just Ive never heard a bad thing about him until I see the comments here.
Physicists show that their ideas have substance by solving problems. But Wolfram’s ideas don’t tell us the masses of the elementary particles, the drag of the flow of water through a pipe, or anything else.
This is why the scientific community doesn’t care about this stuff.
can you explain this more rigorously? I don't see how computation 'destorys' information, unless you are using "destroy" loosely and you just mean exploding the state space?
> One-time $100 donation
This actually had me laugh out loud. I must've been a poor kid
Sorry, I know this is a bit snark-heavy for HN but I can’t help but feel impressed by the way cryptocurrency has somehow succeeded in associating itself with so many ills of modern society.
That seems like something we would want, the ability to freely transfer payment from one individual to another, internationally, contractually, and transparently.
The only interests that I would think would want that gone are those that profit from the many choke points in our financial systems. Sure, speculators and opportunists have leveraged benefits, and they are the ones you always hear about… you don’t hear about the millions of people quietly managing their private and legal financial affairs, because when you use it for that, it just works -exactly as designed.
FWIW I think you can much more easily associate cash with all kinds of shady and socially caustic uses, but for whatever reason not very many cryptocurrency critics are out to abolish cash, which I would think would be the poster child for seedy, shady, toxic commerce.
But, sure, crypto bad and whatever.
And, yes it takes a while to digest...you have to invest some time in reading both authors series on the subject...but its well worth the read.
https://www.scientificamerican.com/article/physicists-critic...
This is a crucial part that many intelligent people somehow utterly fail to understand. If you can explain everything (including the things that are not true), you can explain nothing.
A theory that explains, is a theory that says "...therefore, X can happen, but Y can't happen". Like a mathematician who says that 2+2 is 4, but also says that 2+2 is not 5. Or a physicist who says "apples fall down from the tree, they don't fall up".
Compare that to a "genius" mathematician or physicist who simply says "yes" to everything. Is 2+2=4? Yes. Is 2+2=5? Yes. Do apples fall down? Yes. Do apples fall up? Yes. And then people on internet are deeply impressed that he can answer everything. Such an amazing skill! Ask him about gravitons, he has a clear answer. Ask him about dark matter, he has a clear answer. Ask him about time travel, he also has a clear answer. The only problem is that he can both write a physics that contains gravitons, and a physics that does not contain gravitons. Etc.
Ultimately, we want to know what is real about our universe. (Or multiverse, or whatever.) A model that says "yes" to both the things that are true and the things that are false, is useless. After you figure out what is true, you get "yeah, my model explains that". Problem is, the model explains the opposite just as well.
...then you take a step back, and remember that "can write anything" is simply a different way to say "Turing-complete". Yes, if you invent something that is Turing-complete, you can simulate a universe in it. Any universe. Both the ones that exist, and the ones that don't.
(And the idea of Turing-completeness was discovered a few decades before Wolfram was born. So we can't even credit him with inventing the concept. He just uses the concept to impress people who either never heard about it, or never connected the dots.)
Its insane energy use, slow speed, high transaction costs, and structural inability to have any legal oversight (for eg reversing fraudulent payments) amount to a huge amount of friction.
And the existence of unknown entities with huge wallets that could pump or crash the price of a coin on a whim also means its not 100% transparent.
Is it money? I would say no, but opinions on that can differ.
But sure, there are lousy performers in the space, just as the banking system is a poor performer in energy use and speed for many kinds of transactions.
For example, If you stack up the energy use of financial institutions, many SOTA cryptocurrency systems compare extremely favourably on a per transaction basis.
I think people easily forget that the space is not at all homogeneous, and there are vast differences between different blockchains and tokenisation systems.
Lumping them all together is like saying that all government backed currencies are total crap just because so many currencies have seen catastrophic inflation and counterfeiting in the last century.
Many countries debt backed currency projects are actually fairly stable and well managed.
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.
[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...
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 information encoded in the former invariant. I.e. That information has been destroyed.
The machinery of quantum mechanics (the standard kind with Hilbert spaces) maintains certain invariants that you can compute things from, but Wolfram's stuff can do pretty much anything. Thus, same idea.
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
The author is Jonathan Gorard, who is one of the people associated with “The Wolfram Physics Project”, and checking the references, it does cite at least one document/paper that is part of the “wolfram physics project”,
But I don’t know for sure whether it exactly uses the central framework of the project.
That's obviously not satisfactory as a positive independent assessment, which is what this thread is calling for.
But ultimately it’s up to Wolfram to come up with those things. I don’t think most physicists feel he has done that, especially since the standards increase as the idea becomes more different to existing physics
So why did all the string theories get popular?
A famous example in Physics is String Theory. It has been around since at least 1980s and still no definitive way to prove or disprove it.
The “gravitas” program is open source, so perhaps some external people may have evaluated how useful it is? (Unless it is hard to get running, idk.)
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.
It just popped up on HN. I suggest giving it a read.
String theory is a very rigid coherent theory. It has produced plenty of deep mathematical insights. I personally don't believe that it describes our universe, but it is possible to calculate its properties.
Wolframs "Theory" is a bunch of relatively conventional ideas (by high energy physics theory standards), tied together by wishful thinking and speculation. In parts it seems almost possible to show that the ideas are actually contradictory. It is only saved by being to vague to fail coherence checks.
It is, to use the old cliche, not even wrong.
I've noticed a common tactic in online disinformation campaigns: taking a common term associated with critique of some concept and spamming it in a different (sometimes opposite) context, to break the semantic link.
Unfortunately, there is a ton of misinformation about this topic on the web. For example, people love to say that string theory predicts anything and everything. But it predicts (and rejects) a lot; it’s just that all of the known predictions happen to fall into the categories of (1) predicting things that are very hard for humans to measure (behavior of black holes at long time scales, graviton scattering, etc) or (2) retrodicting things we already know are true (e.g. gravity, Lorentz invariance, etc.). This state of things isn’t by design of nefarious string theorists designing their theory to be untestable, it’s just cruel fate of what comes out of the math. Hopefully someday we can find some other type of prediction, but string theory isn’t easy.
[0] See e.g. https://indico.cern.ch/event/630393/contributions/2890113/at...