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Old 15th April 2020, 03:57 PM   #1
Solitaire
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The Wolfram Physics Project

The Wolfram Physics Project

Apparently he has a project where he looks at all the possible computable
universes and selects the one model that matches ours. Not sure though.

Here's the short summary.
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Old 16th April 2020, 01:25 AM   #2
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That's really cool.
Haven't read the links yet, but I've been hoping he does something like this ever since I read about his ideas on SpaceTime as a network about 5 years ago.
He has a different approach and apparently has managed to derive both GR and SR from first principles using evolving networks with only nodes and connections, SpaceTime being an emergent property of the evolving network.
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Old 16th April 2020, 02:06 AM   #3
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A bit of background from Wired - https://www.wired.com/story/stephen-...solve-physics/
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Old 16th April 2020, 03:33 AM   #4
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I was saying in another thread that there are some cases where it is not possible to determine if something is science or pseudo science. This is just such a case.
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Old 16th April 2020, 03:51 AM   #5
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Originally Posted by Robin View Post
I was saying in another thread that there are some cases where it is not possible to determine if something is science or pseudo science. This is just such a case.
I disagree.
If this is pseudoscience, so is pure mathematics.
It might have nothing to do with how the universe works, but it's still 'mathematics'.
This is just a possible alternative model and this project is searching for models that correspond to the real world.
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Old 16th April 2020, 05:57 AM   #6
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I've seen this comic posted as a response. Also this xkcd.

I don't know enough to know how fair that is, although I think both were posted by physicists. Certainly both clarified that they know the comics don't fit Wolfram 100%, and both concede that Wolfram is very knowledgeable and that they're more commenting on his presentation of his ideas rather than dismissing them out of hand as being wrong.
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Old 16th April 2020, 05:58 AM   #7
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Originally Posted by Robin View Post
I was saying in another thread that there are some cases where it is not possible to determine if something is science or pseudo science. This is just such a case.
I've got the same problem.
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Old 18th April 2020, 03:09 PM   #8
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I wonder how far this approach will get him in quantum physics. The double slit experiment was mentioned, but that is tinker toys.

How is a computational rule going to lead to behaviour like entangled particles?
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Old 18th April 2020, 03:17 PM   #9
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Originally Posted by Robin View Post
I wonder how far this approach will get him in quantum physics. The double slit experiment was mentioned, but that is tinker toys.

How is a computational rule going to lead to behaviour like entangled particles?

Well, first you gotta ask, how is a computational rule going to lead to behavior like... particles?

I've been reading small parts of the 600-page background briefing. It's out there, as in complicated. The type of rule he's discussing is simple, but the resulting behavior and how to evaluate it is complicated. So you have to have a graduate level of understanding of that kind of computation, and of the mathematical underpinnings of multiple theories of particle physics, to try to match them up. Then if you want to look at entanglement, better add the mathematics of quantum physics to your resume.
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Old 18th April 2020, 06:07 PM   #10
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For those interested, I haven't watched it, (I'm one minute in), but Lex Fridman has just released a three hour interview with Steven Wolfram on the Artificial Intelligence Podcast, and based on the description they spend considerable time on this topic. His interviews are usually pretty good.

https://www.youtube.com/watch?v=ez773teNFYA

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Old 18th April 2020, 08:10 PM   #11
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Usually it's easy to spot science absurdity. It is usually fraud or simple crazy.


1. A fraud is self explanatory.
2. Simple crazy - what we see here, talking a lot of complex words they have picked up but really no understanding of any of them.


Now I add a third possibility.


3. Super crazy - very smart, able to discuss complex science concepts and understand them, but then they veer off into ego driven self delusion. A lot of scientists would have thought this of Einstein when he first published his papers on relativity.



This guy isn't a fraud, he isn't simple crazy, but is he super crazy?
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Old 18th April 2020, 09:07 PM   #12
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Originally Posted by Solitaire View Post
The Wolfram Physics Project

Apparently he has a project where he looks at all the possible computable
universes and selects the one model that matches ours. Not sure though.

Here's the short summary.
Each time I see this thread I wonder to myself , “Does he only do his research on a full moon?”.
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Old 18th April 2020, 10:17 PM   #13
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Originally Posted by Myriad View Post
Well, first you gotta ask, how is a computational rule going to lead to behavior like... particles?



I've been reading small parts of the 600-page background briefing. It's out there, as in complicated. The type of rule he's discussing is simple, but the resulting behavior and how to evaluate it is complicated. So you have to have a graduate level of understanding of that kind of computation, and of the mathematical underpinnings of multiple theories of particle physics, to try to match them up. Then if you want to look at entanglement, better add the mathematics of quantum physics to your resume.
I don't have to have QM on.my resume to see the conceptual problem with getting entanglement from a computational rule.
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Old 19th April 2020, 05:50 AM   #14
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Originally Posted by Robin View Post
I don't have to have QM on.my resume to see the conceptual problem with getting entanglement from a computational rule.

No, but you might need it to solve that problem.
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Old 19th April 2020, 05:56 AM   #15
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Originally Posted by a_unique_person View Post
3. Super crazy - very smart, able to discuss complex science concepts and understand them, but then they veer off into ego driven self delusion. A lot of scientists would have thought this of Einstein when he first published his papers on relativity.

This guy isn't a fraud, he isn't simple crazy, but is he super crazy?

"I mean, this is the world's smartest man we're talking about, so who's to say? How can anyone tell if he's gone crazy?" -- Watchmen (Dan Dreiberg/Night Owl regarding Adrian Veidt/Ozymandias)
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Old 19th April 2020, 08:06 AM   #16
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If key results from known physics - the Standard Model of particle physics, and GR, say - emerge from this approach (in an objectively independent way, of course), this project will be at the starter’s block.

Solve a key open problem - the measurement problem in QM, say, or the neutrino mass hierarchy - and things would start to get interesting.

Coming up with a way to test, today, whatever emerges from this project as quantum gravity would set Wolfram on the path to a Nobel.
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Old 20th April 2020, 11:25 AM   #17
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Wondered what had happened to this a few times over the years. When he first came out with this I spent some time many years ago trying to get my head around it but it was and is way beyond my ability to understand it to a level that I can have a real informed opinion about it.

If I recall correctly he doesn’t only think this is a model of reality but this is what “reality” IS, so the map is the territory. Is that a fair summary?
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Old 20th April 2020, 04:55 PM   #18
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Originally Posted by Darat View Post
If I recall correctly he doesn’t only think this is a model of reality but this is what “reality” IS, so the map is the territory. Is that a fair summary?
I think it's more like "the map is an accurate description of the territory". If I say "that apple is red", I'm not saying that the apple is the word red, but that the word red accurately describes the color of the apple.

If he's right (and as I understand it the project isn't finished yet), this isn't just an approximation to a more fundamental model, but describes the fundamental nature of reality. I don't think there's any problem of mistaking the map for the territory, though.
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Old 27th April 2020, 04:09 PM   #19
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I think biggest advantage of his project is that it may end up being useful even if his grand claims and predictions won't come to pass.

His basic thesis is that very simple rules can result in very complex behavior. He concludes that our universe is likely to be run on such set of simple rules and proposed candidate for those: nodes with relationships, where rules govern how those relationship and nodes change.

What I think about it? It is pretty much shoot in dark. If it will be ever possible to verify his work, it won't be any time soon.

But I certainly do NOT consider "universe runs on very simple rules" as some crank idea. In fact, for me it is pretty plausible.

My biggest criticism is that he is going about it like that: identifying various features in his graphs and how they change and how we read them and claiming those correspond to things like space, time, particles etc. That's a little... unconvincing, to be honest. Though I am just interested layman.
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Old 27th April 2020, 08:58 PM   #20
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I think people already knew about the simple rules. String theory is, at its heart, a very simple idea.
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Old 27th April 2020, 09:04 PM   #21
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The "simple rules resulting in complex behaviour" idea has been around for thousands of years, since the pre-Socratic philosophers and is uncontroversially a mainstream idea in physics today.
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Old 29th April 2020, 07:25 PM   #22
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Originally Posted by Robin View Post
The "simple rules resulting in complex behaviour" idea has been around for thousands of years, since the pre-Socratic philosophers and is uncontroversially a mainstream idea in physics today.

Chaos theory is all about very simple rules producing very complex behaviour. Example

x1=ax0(1-x0) Where
x1 = the next iteration of x0
x0 = initially any number 0 < x < 1
a= a constant.

For low values of a the result is predictable. When a is increased the result switches between two values. Increase a and the results keep on doubling. Then at high values of a the results become chaotic. What is interesting is that for some values of a the results become predictable.
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Old 29th April 2020, 07:44 PM   #23
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Originally Posted by Robin View Post
The "simple rules resulting in complex behaviour" idea has been around for thousands of years, since the pre-Socratic philosophers and is uncontroversially a mainstream idea in physics today.
I'm familiar with it as far back as John Conway and Life. I wonder what the earliest attestation of the concept actually is.
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Old 29th April 2020, 08:22 PM   #24
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Originally Posted by theprestige View Post
I'm familiar with it as far back as John Conway and Life. I wonder what the earliest attestation of the concept actually is.
We don't have many primary sources for the pre-Socratic natural philosophers so we have to depend upon second hand sources, such as Aristotle.

For example in Physics, Aristotle describes Democritus's view that there are only atoms and the void and that all the phenomena that there are can be ascribed to the interaction of atoms of different shapes and sizes.

In "On the Heavens" Aristotle describes Democritus's account of how buoyancy can arise from the lower level interaction of particles of different shapes and sizes.

We know that Democritus ascribed all phenomena, including minds, to the interaction of atoms of different shapes and sizes.

This is a clear example of the concept of complex phenomena arising from simple rules being proposed nearly 2 and a half millenia ago.
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Old 29th April 2020, 08:30 PM   #25
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Originally Posted by Robin View Post
We don't have many primary sources for the pre-Socratic natural philosophers so we have to depend upon second hand sources, such as Aristotle.

For example in Physics, Aristotle describes Democritus's view that there are only atoms and the void and that all the phenomena that there are can be ascribed to the interaction of atoms of different shapes and sizes.

In "On the Heavens" Aristotle describes Democritus's account of how buoyancy can arise from the lower level interaction of particles of different shapes and sizes.

We know that Democritus ascribed all phenomena, including minds, to the interaction of atoms of different shapes and sizes.

This is a clear example of the concept of complex phenomena arising from simple rules being proposed nearly 2 and a half millenia ago.
Aristotle himself suggested that it was plausible that there were only three principles, consisting of a binary relation (a contrariety) and a substratum.
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Old 7th May 2020, 01:24 AM   #26
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https://www.scientificamerican.com/a...of-everything/

What scientists think? Not much.
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Old 9th May 2020, 12:08 PM   #27
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Essentially he's presenting a model of computation, let's call it a graph machine, which is equivalent to several other models of computation, it can simulate a universal Turing machine and it can be simulated by a universal Turing machine. A program running on that graph machine consists of a set of update rules and an initial configuration.

Every program corresponds to a computable function, so if (our model of) the universe is computable then a program exists which computes said function on the graph machine. He hopes that the program which corresponds to the universe is short and that the particular way of encoding it on a graph machine results in intuitive connections between resulting features of the graph and physical entities.

It's a pretty cool thing, but it's computer science and not physics. Ultimately it's no different from writing different python programs trying to find a model for the universe, except that the source code looks different (python code vs sets of update rules/initial graph configurations), it runs on a different machine (your standard pc vs an abstract graph machine), and that physical entities correspond to different encodings (arbitrary blobs of 0's and 1's in a big linear bit-array that is your pc memory vs features on abstract graphs). The other point, hoping that it will be in particular a short program that corresponds to our universe, seems the same irrespective of the encoding (IIRC the Kolmogorov complexity of an object differs only up to a constant if you change the encoding).
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