Recent content by Nick2014

OK, thanks :)

And then, to obtain that relation?

Hi everybody! Can you explain me how I can obtain wave equation given a metric? For example, if I have this metric $$g_{μν}=diag(−e^{2a(t)},e^{2b(t)},e^{2b(t)},e^{2b(t)})$$, how can derive the relation $$\frac{1}{\sqrt{g}}\partial _t(g^{00}\sqrt{g}\partial _t...

very thanks :)

Thanks :) but in my case we are in six dim not four... Then, there is no matter terms... My professor says this...

Hello everyone! I have a "great" problem with EGB action. First of all, I'm used to work with potential and scalar field, but now I have the following action ##S=\int\sqrt{-g}\left(2\beta +R+\alpha GB\right)d^6 x## where GB is the six-dimensional Gauss-Bonnet term, R is the scalar curvature...

Hello everyone! I'm a mathematician from University of Cagliari (Italy). I'm a newbie in this field and I hope somebody can help me to solve my "particular" doubts :p