Peter Woit, University of Columbia, ‘Towards a Grand Unified Theory of Mathematics and Physics’.
A paper which outlines some of the already established connections between number theory and physics, acknowledges that there are as yet no satisfactory explanations for these connections, and concludes it is an area which deserves much more attention.
Essentially, the theory of everything set out here on this site argues that a grand unified theory of mathematics and physics requires only that mathematicians and physicists drop their peculiar insistence that number theory is nothing more than an abstract human concept.
It should be uncontroversial to state that 1a+2a=3a is clearly, self-evidently, a law of physics.
What constraints there may be on how the mathematical complexity of a physical universe develops from first principles, is a matter for focused investigation.