Property antisymmetric tensors

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Homework Statement



I was wondering how I could prove the following property of 2 antisymmetric tensors F_{1\mu \nu} and F_{2\mu \nu} or at least show that it is correct.

Homework Equations


\frac{1}{2}\epsilon^{\mu \nu \rho \sigma} F_{1\rho \sigma}F_{2\nu \lambda} + \frac{1}{2}\epsilon^{\mu \nu \rho \sigma} F_{2\rho \sigma}F_{1\nu \lambda} = - \frac{1}{4} \delta^{\mu}_{\lambda} \epsilon^{\rho \sigma \alpha \beta} F_{1 \alpha \beta}F_{2\rho \sigma}

The Attempt at a Solution


If \mu = \lambda, the left side gives - \epsilon^{\rho \sigma \alpha \beta} F_{1 \alpha \beta}F_{2\rho \sigma} and the right side also ( summing over \mu )

But how can I see that if \mu is different from \lambda, that this relation is true? The right hand side is zero, but how can I proof that the left side is also zero? I have no idea..
 
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The indices are incorrectly balanced, there is a /nu on the LHS but none on the RHS
 
hunt_mat said:
The indices are incorrectly balanced, there is a /nu on the LHS but none on the RHS

The \nu is contracted, only \mu and \lambda are free indices.
 
Solved.
 
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