- #1

lennyleonard

- 23

- 0

*Gauge*covariant derivative, defined by [tex]D_{\mu}=\partial_{\mu}-iW_{\mu}^a(x)\,T^a[/tex]where the [itex]W_{\mu}^a(x)[/itex]s are the gauge fields and the [itex]T^a[/itex]s are the generators of the Lie algebra.

They seem quite different to me: the former deals whit the fact that the basis vectors may vary from point to point (like the polar basis vectors): it has therefore a very simple geometrical interpretation.

The latter instead have been introduced (as far as I know) to make gauge invariant (according to the gauge group concerned) the equations to which it's applied, but I don't see any geometrical wiew to this, although I guess it has to have one!

Can you tell me what is it (if there actually is one!)?