Can we talk on the conservation of spin?

Question

We studied in class different quantum numbers such as charge, isospin, strangness and others, and classified them as conserved or non conserved in each of the strong nuclear, weak nuclear, and EM interactions. However, we didn't mention the spin. Can we talk on the conservation of spin in the sense that the sum of spins on both sides have to be equal? If yes, then in what interactions is it conserved?

anna v · Accepted Answer

What is conserved is total angular momentum. Spin is an intrinsic angular momentum and has to be accounted for in an interaction, only in the sums.
Example: the $π^0$
has zero spin but decays into two photons, each photon has a spin of angular momentum 1. The spin projections of the photons should add to zero so that angular momentum is conserved.

Can we talk on the conservation of spin?

One Answer

Add your own answers!

Ask a Question