Make sure the Lagrangian symmetry?

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centry57
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Is the Lagrangian of the neutral Proca field
[tex]\mathcal{L}=-\frac{1}{16\pi}\left(F^{\mu\nu}F_{\mu\nu}-2m^2 A_{\mu} A^{\mu}\right)[/tex]
symmetric?
And How to make sure whether it's symmetric.
 
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centry57 said:
Is the Lagrangian of the neutral Proca field
[tex]\mathcal{L}=-\frac{1}{16\pi}\left(F^{\mu\nu}F_{\mu\nu}-2m^2 A_{\mu} A^{\mu}\right)[/tex]
symmetric?
And How to make sure whether it's symmetric.

Symmetric in what?

AB
 
I mean if the Stress-energy momentum has the form [tex]T_{\mu\nu}=T_{\nu\mu}[/tex]
 
Well, take the functional derivative with respect to the metric of this Lagrangian. What do you get?

If the EM-tensor is not symmetric, you can construct the so-called Belinfante tensor; see for instance DiFrancesco's "Conformal Field Theory", 2.5.1 :)