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by jiggawatts 698 days ago
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.
1 comments
imglorp 698 days ago
I saw a claim that they had produced GR from their model. Does that count for anything?
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jiggawatts 698 days ago
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...

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