Property antisymmetric tensors

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Homework Help Overview

The discussion revolves around proving a property related to two antisymmetric tensors, F_{1\mu \nu} and F_{2\mu \nu}. The original poster seeks to establish the validity of a specific equation involving these tensors and the Levi-Civita symbol.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to analyze the equation by substituting specific values for indices and questioning how to demonstrate the equality when the indices differ. Some participants point out potential issues with index balancing in the equation presented.

Discussion Status

The discussion includes attempts to clarify the structure of the equation and the implications of index contraction. While some participants raise concerns about the correctness of the indices, the original poster is exploring the proof without reaching a consensus or resolution.

Contextual Notes

There is a focus on the proper handling of indices in tensor equations, with specific attention to the implications of free and contracted indices. The original poster expresses uncertainty about proving the case when indices differ.

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Homework Statement



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

Homework Equations


[tex]\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}[/tex]

The Attempt at a Solution


If \mu = \lambda, the left side gives [tex]- \epsilon^{\rho \sigma \alpha \beta} F_{1 \alpha \beta}F_{2\rho \sigma}[/tex] 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..
 
Last edited:
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The indices are incorrectly balanced, there is a [tex]/nu[/tex] on the LHS but none on the RHS
 
hunt_mat said:
The indices are incorrectly balanced, there is a [tex]/nu[/tex] on the LHS but none on the RHS

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

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