Recent content by maykot

Actually, according to the link you posted, I don't think that it's j^{\mu} A_{\mu} that is independent, but \sqrt{g} j^{\mu} A_{\mu} . If it was the former, then the SET would correspond to case (ii) mentioned earlier, instead of not contributing to the SET at all. And yes, Greiner...

Kinda... I don't see why I have to vary A_{\mu} as well as g_{\mu\nu} . You yourself said that A_{\mu} is metric independent, so it shouldn't add anything to the SET. However, Ron Maimon's last paragraph sounds reasonable to me. If you fix \sqrt{g} j^{\alpha} while varying the metric...

Thank you for your reply Bill_K. I found out what was wrong with the above derivation that t_{\alpha\beta} \neq g_{\alpha\mu} g_{\beta\nu} t^{\mu\nu} , I implicitly, and erroneously, assumed that g^{\alpha\mu} g^{\beta\nu} \frac{\partial}{\partial g^{\alpha\beta}} = \frac{\partial}{\partial...

This thread is supposed to be a continuation of the discussion of this thread: (1) https://www.physicsforums.com/showthread.php?t=88570. The previous thread was closed but there was a lot of things I did not understand. This is also somewhat related to a recent thread I created: (2)...

I traced the problem back to the expression \frac{\partial g_{\alpha\beta}}{\partial g_{\mu\nu}} = \delta ^{\mu}_{\alpha} \delta ^{\nu} _{\beta} . It is not symmetric under \mu \to \nu nor \alpha \to \beta . This is the expression I've always used to derive the energy momentum tensor, but I...

First of all, I'm not sure if this thread belongs here or at the "Special & General Relativity" sub-forum, if I posted at the wrong place please move it. Homework Statement I encountered this problem working in my master's degree. I need to find the stress-energy tensor of the following...