Hi(adsbygoogle = window.adsbygoogle || []).push({});

Can anyone explain how to vary an action e.g [itex]\int d^4 x e [\frac{1}{2}\partial_{\mu}\partial^{\mu} \phi + i\bar{\psi}\bar{\gamma}^{\mu}D_{\mu}\psi] [/itex] w.r.t the vierbein?

Where e here is the determinant of the vierbein, and [itex]D_{\mu} [/itex] is = to [itex]\partial_\mu + \frac{1}{4}\gamma_{\alpha \beta} \omega_{\mu}^{\alpha \beta} [/itex]

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Varying with respect to vierbein

**Physics Forums | Science Articles, Homework Help, Discussion**