# Tagged Questions

44 views

### F-mu-nu notation [on hold]

This is a really simple question that I cannot find an answer to, strangely enough. What do these (similar) notations stand for: $F^{\mu\nu}$ $F_{\mu}^{\nu}$ $F^{a\mu\nu}$ etc etc.
184 views

### How to properly construct the electromagnetic tensor in curved space-time?

How do I properly construct the electromagnetic tensor in curved space-time? I have my curved spacetime metric $(+,-,-,-)$ and my magnetic vector potential $A$. I tried two ways but not sure which is ...
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### Homogeneity and isotropy of stress energy tensor

Given the energy momentum tensor in E&M: $T_{\mu\nu} = -F_{\mu\alpha} g^{\alpha \beta} F_{\beta \nu} +\frac{1}{4} g_{\mu \nu} F_{\sigma \alpha} g^{\alpha \beta} F_{\beta \rho} g^{\rho \sigma}$ I ...
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### Has a metric formulation of electromagnetism ever been attempted? [duplicate]

I understand that electromagnetic fields carry energy, and this energy curves spacetime gravitationally. That's not my question. I'm asking if anyone has tried to formulate electromagnetism in such ...
93 views

### Solving electromagnetic vector field using the Lagrangian

Given an action of the form $$S=-\frac{1}{4}\int d^4x\eta^{\mu\nu}\eta^{\lambda\rho}F_{\mu\lambda}F_{\nu\rho}$$ where ...
I've seen the Kaluza-Klein metric presented in two different ways., cf. Refs. 1 and 2. In one, there is a constant as well as an additional scalar field introduced: \tilde{g}_{AB}=\begin{pmatrix} ...