# Gordon identity manipulation?

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1. Feb 16, 2016

### Higgsy

The Gordon identity allows us to solve using

$$2m \bar{u}_{s'}(\textbf{p}')\gamma^{\mu}u_{s}(\textbf{p}) = \bar{u}_{s'}(\textbf{p}')[(p'+p)^{\mu} -2iS^{\mu\nu} (p'-p)_{\nu}]u_{s}(\textbf{p})$$

But how would we solve for

$$2m \bar{u}_{s'}(\textbf{p}')\gamma^{\mu}v_{s}(\textbf{p})$$

Would a rederivation of the Gordon identity be required?

2. Feb 22, 2016