- #1
ismaili
- 150
- 0
Say, \psi^1,\ \psi^2 are Dirac spinors, and M is a matrix composed of Dirac matrices. Is the following equation hold?
\bar{\psi^1}M\psi^2 = -\Big(\bar{\psi^1}M\psi^2\Big)^T
I'm not quite sure, here is my derivation:
<br /> \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<br />
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?
\bar{\psi^1}M\psi^2 = -\Big(\bar{\psi^1}M\psi^2\Big)^T
I'm not quite sure, here is my derivation:
<br /> \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<br />
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?
