- #1

Strangelet

- 4

- 0

## Homework Statement

I have to expand the following term:

$$\dfrac{1}{4} F_{\mu\nu}F^{\mu\nu} = \dfrac{1}{4} \left(\partial_{\mu}A_{\nu} - \partial_{\nu}A_{\mu}\right) \left(\partial^{\mu}A^{\nu} - \partial^{\nu}A^{\mu}\right)$$

to get in the end this form:

$$\dfrac{1}{2}\left(\partial_{\mu}A_{\nu}\right) \left(\partial^{\mu}A^{\nu}\right) - \dfrac{1}{2}\left(\partial_{\mu}A^{\mu}\right)^2$$

## Homework Equations

I really don't know how to make the calculation. I tried to multiply terms but I think I din't get some rule about index.. sigh!