Chern-Simons and massive A^{\mu}

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IRobot
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Hi, I am struggling with a problem in field theory:
We are looking at a Chern-Simons Lagrangian describing a massive A field:
[itex]L = -\frac{1}{4} F^{\mu\nu}F_{\mu\nu}+\frac{m}{4}\epsilon^{\mu\nu \rho}F_{\mu\nu}A_{\rho}[/itex]
I find those field equations:
[itex]\partial_{\mu}F^{\mu\lambda}=-\frac{m}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu}[/itex] and now I need to show that F satisfies the Klein-Gordon equation: [itex](\Box+m^2)F_{\mu\nu}=0[/itex] using the EL equations, but after a time playing with both equations, I still can't prove that.
 
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It's normal here to introduce the dual of the field strength

[tex]\tilde{F}^\lambda = \frac{1}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu}.[/tex]

Then taking the divergence of your equation of motion above yields [itex]\partial_\lambda \tilde{F}^\lambda = 0,[/itex] while multiplying by an appropriate epsilon yields the KG equation for [itex]\tilde{F}^\lambda[/itex].
 
fzero said:
It's normal here to introduce the dual of the field strength

[tex]\tilde{F}^\lambda = \frac{1}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu}.[/tex]

Then taking the divergence of your equation of motion above yields [itex]\partial_\lambda \tilde{F}^\lambda = 0,[/itex] while multiplying by an appropriate epsilon yields the KG equation for [itex]\tilde{F}^\lambda[/itex].
Thanks a lot. I did manage to find the Klein Gordon equation for the dual, then it's just a matter of applying another LeviCivita to find it for the "regular" form. ;)