[evanb]

I'm confused by this 'hypothesis'

>My guess is that once you consider all of the symmetries that could exist (and there are many which have not yet been found; supersymmetry has long been posited but remains undiscovered), then our laws of physics are basically the only laws that can exist in a mathematically consistent way.

If physical evolution is unitary, it may be phrased in terms of an S-matrix, and the possible symmetries of the S-matrix are well-known by the Coleman-Mandula theorem[0] and its supersymmetric generalization[1]. So, supersymmetry is possible, but, as you rightly point out, may or may not exist in the world. So mathematical consistency (unless what you mean is that quantum gravity might violate one of the assumptions of those theorems) is a lot less powerful than you guess.

[0] https://en.wikipedia.org/wiki/Coleman%E2%80%93Mandula_theore...

[1] https://en.wikipedia.org/wiki/Haag%E2%80%93Lopuszanski%E2%80...

[Xcelerate]

Huh, interesting. I was not aware of this. Thanks for the link!