[criddell]

Tegmark's theory says exactly that - the particles are ultimately mathematics. Not that they can be modeled with mathematical methods, but that they are actually constructed from mathematical structures.

It's definitely not a mainstream theory.

[goatlover]

What does the mean, though? Mathematics as we understand it is an abstraction. If the universe is fundamentally abstract, what breathes fire into the models? Consciousness?

[wcoenen]

Modal realism. A mathematical structure is "real" to its conscious inhabitants (if any), and merely an abstraction from the perspective of those who are not, i.e. the inhabitants of other mathematical structures.