Transpose of Grassmanian variables

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SUMMARY

The discussion centers on the mathematical relationship involving Dirac spinors, specifically the equation \(\bar{\psi^1}M\psi^2 = -\Big(\bar{\psi^1}M\psi^2\Big)^T\). The derivation confirms that the transpose operation does not alter the sign of the equation, validating the equality. The participants agree that the manipulation of the Dirac matrices and the properties of the transpose are correctly applied in the derivation process.

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  • Understanding of Dirac spinors
  • Familiarity with matrix operations, specifically transpose
  • Knowledge of properties of Dirac matrices
  • Basic grasp of linear algebra concepts
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This discussion is beneficial for physicists, mathematicians, and students studying quantum mechanics or theoretical physics, particularly those focusing on spinor algebra and matrix operations.

ismaili
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Say, [tex]\psi^1,\ \psi^2[/tex] are Dirac spinors, and [tex]M[/tex] is a matrix composed of Dirac matrices. Is the following equation hold?
[tex]\bar{\psi^1}M\psi^2 = -\Big(\bar{\psi^1}M\psi^2\Big)^T[/tex]
I'm not quite sure, here is my derivation:
[tex] \bar{\psi^1}M\psi^2 = \bar{\psi^1}_{i}M_{ij}\psi^2_j = - \psi^2_jM^T_{ji}\psi^1_i = -\Big(\psi^1_iM_{ij}\psi^2_j\Big)^T = -\Big(\psi^1M\psi^2\Big)^T[/tex]
where the last step, i.e. the third equality is what I'm worried about. I originally think that the change of order of the third equality is totally due to the operation of transpose (superscript "T"), so there is no need to change sign in the third equality.
Am I right?
 
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Yes, you are right. The transpose operation does not change the sign of the equation, so the third equality is correct.
 

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