- #1

earth2

- 86

- 0

There are those vectors made of Pauli matrices like

[itex]\bar{\sigma}^\mu[/itex] and [itex]{\sigma}^\mu[/itex]. So if I have the product

[itex]\bar{\sigma}^\mu {\sigma}^\nu[/itex] I wonder if it is commutative? And if not, what is the commutator?

Cheers,

earth2