There isn’t a Nobel prize for mathematics. There is the Fields medal but it is different, and not handled by the same organization.

True, but that's not a very good reason for giving a Nobel Prize in Physics to something that isn't physics. I think the standard way of giving a Nobel Prize to mathematicians is to call it economics.

There is no Nobel Prize in Mathematics.

the Nobel Prize doesn't do mathematics.

Further: the "Nobel equivalent" maths prize is the Fields Medal:

<https://en.wikipedia.org/wiki/Fields_Medal>