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How to Think Computationally about AI, the Universe and Everything

writings.stephenwolfram.com

41–50 of 81 posts

Re: How to Think Computationally about AI, the Universe and Everything

#41

Earlier quoted context omitted.

It doesn't prove anything. It does make his Jordan comparison disingenuous at best. It's weird enough to gatekeep posting theories (nobody has to believe or even seriously consider them!), even odder to do so for a PhD holder in the field.

Disagree. It’s not weird at all, and I would say quite productive, being that a billionaire crank is a potentially dangerous, with nearly unlimited ability to attempt to spread his influence countering it requires people to speak up.

By the same token, why should i take anything kromem says with anything but a grain of salt ? What are his credentials ? as far as anyone "being swayed" is concerned, he's a random on the internet. He's not changing minds.

You'll have a much better time telling people how and why those "billionaire crankers" are not making sound arguments than trying to gatekeep what they say. Even then, that's no guarantee.

all in all, the idea that people "speaking up" in this way does anything at all is fairly wishful thinking.

Re: How to Think Computationally about AI, the Universe and Everything

#42

Earlier quoted context omitted.

I am very aware of what the Club of Rome is/was. I don't understand what the sentence means.

The last sentence said something about a computationally stable (model/state) of society. I suppose such stability would be helpful in looking for a sustainable economy or society. But I'm not clear either, on what that sentence means.

We keep trying to measure, calculate, forecast, then offset our world by building increasingly complex system to keep it “stable state” which we then errantly call “natural.”

Re: How to Think Computationally about AI, the Universe and Everything

#43
post #14

This is hard to read. I don't think the core narrative is implausible, but it's pretty hard to imagine someone this self-aggrandizing being a sufficiently critical adversary of his own theory, and he doesn't seem to have convinced anyone else of his claims.

You don't think it's implausible? Reading this line didn't set off any red flags? "And that the structure of space and everything in it is just defined by the network of relations between these elements—that we might call atoms of space. It’s very elegant—but deeply abstract." How about this one, shortly after describing "in the history of science there's four models": "But now there’s something even more: in our Phy…

> So then here’s the big result. What observers with those characteristics perceive in the ruliad necessarily follows certain laws. And those laws turn out to be precisely the three key theories of 20th-century physics: general relativity, quantum mechanics, and statistical mechanics and the Second Law." How convenient.

If QM and GR turned out to be required by the anthropic principle it would be a pretty big deal.

But those two theories are known to be incomplete and incompatible, so I would really like to think that this is incorrect.

Re: How to Think Computationally about AI, the Universe and Everything

#44

Its harsh to say it, but Wolfram tried his best at a computational theory of everything and failed. We didn't know this is in the eighties, when the first cellular automata ideas were conceived. So it was a worthy thing to explore in earnest. But it did not work. There is nothing to show for it. It did not strike a vein. These things happen. All the time. You have a great startup idea but no market fit. In this case…

Here's the fundamental problem with Wolfram's approach: he 1) came up with a model of physics (which is fine), 2) noticed that it reproduced many of the normal things that are necessary in a viable theory of everything, like the basic results of quantum physics and relativity (also fine), and 3) declared success, taking 2) as an indication that he's absolutely right and this is the real theory of everything and we're done. It's 3) that's absolutely not fine, and I'm not convinced that Wolfram fully gets why.

It's extremely easy to come up with models that reproduce most of modern physics if you at all know what you're doing. String theory does it, loop quantum gravity does, and so on. There are deterministic models that avoid the "God playing dice" aspects of quantum mechanics yet still reproduce all the classic results. There are rods + gears models of electromagnetism that give the right numbers even though the mechanisms are ludicrous.

The fact that it is so easy to come up with models that match modern physics is in itself a meaningful and not at all obvious thing, but it ultimately derives from the fact that the real universe seems to operate on laws that spring directly from symmetry principles. It turns out that most of the physics that matters is extremely "natural" and can be derived as a consequence of much simpler assumptions than you'd expect, even if the math that gets you from those assumptions to the resulting mechanics can be intense. If you're unfamiliar with this concept but understand calculus, you owe yourself a very deep dive on Noether's theorem, the way that symmetry radiates into every aspect of physics is one of the most profound things to study in physics.

The upshot of Noether's theorem and the ubiquity of its applications in modern physics is that it's very easy to create a theory that matches the predictions of e.g. special relativity: you just need to sneak it in by, for instance, defining your "foliations" in such a way that you have Lorentz symmetry, then everything else comes for free. If you want general relativity, then you (mostly) just need invariance under diffeomorphisms, which is really frickin easy to build into the limit of any graph-based model since you're basically redefining space altogether. I still don't entirely understand how Wolfram gets quantum theory in there; I don't doubt that his model does actually do it at a mathematical level, I just can't stand the verbose writing style and have too little interest in his particular theory to work through it, but once you start talking about constantly branching and recombining state graphs and stuff like that it's not at all hard to imagine that you could pick your definitions in such a way that Hilbert spaces pop out and then you define observers/observations in a way that makes it cleanly match a many-worlds interpretation of quantum mechanics.

But the fact that you have a model that reproduces all of known physics doesn't mean anything. We already have several of those. And people rightly criticize even the top contenders on the basis that they all tend to suffer from the same defect, they're overparameterized and could predict a lot of universes that don't work the way ours does, and there are very few experiments that would rule the models out altogether (rather than merely constrain the parameters). To the extent that their predictions differ from what current theory would predict, their parameters could be easily tuned to match almost any result, which makes it tough to have any faith that the goalposts wouldn't be moved when results did come in that could test, say, the extreme conditions where quantum gravity would be relevant. Wolfram's is no different, except that as far as I can tell he hasn't gone anywhere near as far as e.g. the string theorists in working out what the different predictions would even be for his theory. He's just blindly declaring it correct.

Models are great, and I think there is something useful in Wolfram going down the rabbit hole in terms of showing what a model that reproduces quantum effects looks like, I feel like that is underexplored (the rules of quantum mechanics are usually taken as a given, even in theories of "everything"). But his breathless declarations of having solved physics are ludicrous, and I feel like his ideas might actually be taken much more seriously if he had a more realistic understanding of what he was working with.

Re: How to Think Computationally about AI, the Universe and Everything

#45

Its harsh to say it, but Wolfram tried his best at a computational theory of everything and failed. We didn't know this is in the eighties, when the first cellular automata ideas were conceived. So it was a worthy thing to explore in earnest. But it did not work. There is nothing to show for it. It did not strike a vein. These things happen. All the time. You have a great startup idea but no market fit. In this case…

Here's the fundamental problem with Wolfram's approach: he 1) came up with a model of physics (which is fine), 2) noticed that it reproduced many of the normal things that are necessary in a viable theory of everything, like the basic results of quantum physics and relativity (also fine), and 3) declared success, taking 2) as an indication that he's absolutely right and this is the real theory of everything and we're…

I'm sympathetic to your take on how overly grandiose the language is, but I also think you're being too harsh here.

The idea that the universe is discrete/computational is a fine idea, but underspecified and useless on its own. There's an infinite array of computable rules to choose from. But the fact that with a few assumptions on the rules you can then limit to both GR and QM is very non-trivial and, in my opinion, pretty surprising.

To your point, does it prove that this is _the_ correct theory? Definitely not, and metering language around the claims is important. Still, the result feels novel, surprising, and worthy of further investigation, alongside the other popular models being explored. I think it's a shame that Wolfram's demeanor turns people off from the work.

Re: How to Think Computationally about AI, the Universe and Everything

#46

Earlier quoted context omitted.

You might really enjoy All Watched Over By Machines of Loving Grace. He wasn’t the first to try this, and many failed before him. Most people don’t know that the entire concept of the “ecosystem” comes from a computational view of ecology. It’s bigger problem than just to this. It’s that we’ve based everything off the Club of Rome style mindset of society and it’s all failed. But we haven’t figured out another way. S…

> It’s that we’ve based everything off the Club of Rome style mindset of society What is this supposed to be a reference to?

Wiki link: https://en.wikipedia.org/wiki/Club_of_Rome

Re: How to Think Computationally about AI, the Universe and Everything

#47

Computational irreducibility is a very useful concept; among other things, it is an elegant way to have free will in a deterministic universe.

Can you explain how this creates free will?

One might use computational irreducibility to says that the only way to predict your behavior is to observe your behavior. Any system that could predict you must first recreate you. For those that see determinism as undermining free will, this gives one way to conceptualize the idea that you have ownership of your choices despite determinism.

Re: How to Think Computationally about AI, the Universe and Everything

#49

Earlier quoted context omitted.

It doesn't prove anything. It does make his Jordan comparison disingenuous at best. It's weird enough to gatekeep posting theories (nobody has to believe or even seriously consider them!), even odder to do so for a PhD holder in the field.

Disagree. It’s not weird at all, and I would say quite productive, being that a billionaire crank is a potentially dangerous, with nearly unlimited ability to attempt to spread his influence countering it requires people to speak up.

Nothing in his sentences have to do with being a billionaire. Are we going to accuse him of being a werewolf next Tuesday?

Re: How to Think Computationally about AI, the Universe and Everything

#50

Earlier quoted context omitted.

The last sentence said something about a computationally stable (model/state) of society. I suppose such stability would be helpful in looking for a sustainable economy or society. But I'm not clear either, on what that sentence means.

We keep trying to measure, calculate, forecast, then offset our world by building increasingly complex system to keep it “stable state” which we then errantly call “natural.”

What a fantastic one sentence summary of taoism and certain schools of anarchism.
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