# Parity Operations and CPT Theorem

1. Nov 6, 2013

### physforums

Hey all,

I have a four part question:

1. The problem statement, all variables and given/known data

Let ψ represent a wave function where x,y,z are spatial coordinates and t is time. The particles $\pi^{-}$, $\pi^{0}$, $\pi^{+}$ are pions ($\pi$ mesons). The parity inversion operation is represented by

3. The attempt at a solution

Parities involve a simple change in sign with regards to the components.

∴Pψ(x,y,z,t)=ψ(-x.-y,-z,-t)

Part B

1. The problem statement, all variables and given/known data

The time reversal of above qs is represent by?

3. The attempt at a solution

I am not sure if this is inversion of the components (xyzt) or inverting the sign of the pi mesons. My answer is but not sure:

Tψ(x,y,z,t)=ψ(-x.-y,-z,t)

Part C

1. The problem statement, all variables and given/known data

For first question, charge conjugation is what?

3. The attempt at a solution

C$\pi^{-}$ = $\pi^{+}$, C$\pi^{+}$=$\pi^{-}$, C$\pi^{0}$ = $\pi^{0}$

This seems straight forward but maybe too straight forward?

Part D

1. The problem statement, all variables and given/known data

According to the CPT theorem, if P is violated in an experiment and T is not, then we know what?

3. The attempt at a solution

Since CP are always grouped, the answer would be:

C is also violated?

Help anyone,

Thanks

2. Nov 6, 2013

Hi,