# Parity of a wavefunction

1. Jan 11, 2008

### opous

Can anyone help me understand what is meant by the "parity of a wavefunction"?

I know in terms of even/odd parity, that:

$$P \Psi(x,y,z) = \pm \Psi(x,y,z)$$

ie, P = +/- 1

But I don't know what "parity of a wavefunction" physically means...

2. Jan 13, 2008

### pam

The P operator turns $${\vec r}\rightarrow -{\vec r}$$.

Last edited: Jan 13, 2008
3. Jan 13, 2008

### malawi_glenn

you can also relate this to ordninary functions.

P(cos(x)) = cos(-x) = cos(x) ; so cos is an even function -> Symmetric

P(sin(x)) = sin(-x) = -sin(x) ; so sin is an odd function -> Anti-Symmetric