Accompanying major for theoretical physics

[Akirus]

How useful would a pure mathematics major be if I want to do theoretical physics? Third level physics subjects don't have third level maths as co-requisites, but would it be recommended to take at least some anyway? I want to do a theoretical physics/theoretical astrophysics double major, but I was thinking it might be prudent to try squeeze in some maths as well.

[QuantumJG]

How useful would a pure mathematics major be if I want to do theoretical physics? Third level physics subjects don't have third level maths as co-requisites, but would it be recommended to take at least some anyway? I want to do a theoretical physics/theoretical astrophysics double major, but I was thinking it might be prudent to try squeeze in some maths as well.

I know at UoM mathematical physics sets you up for theoretical physics as you drop the more experimental physics subjects for more mathematical rigour. As for a pure maths major, you will definately have the maths needed and if you try doing a minor in physics.

I personally would love to get into the physics where you look at the real weird stuff!