Is the Inner Product for Dirac Spinors Antisymmetric?

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SUMMARY

The discussion focuses on proving the antisymmetry of the inner product for Dirac spinors, specifically demonstrating that \(\psi (\gamma^a\phi)=-(\gamma^a\phi)\psi\). Key equations referenced include the anticommutation relation \(\{\gamma^a, \gamma^b\}=\gamma^a\gamma^b+\gamma^b\gamma^a=2\eta^{ab}I\) and properties of the gamma matrices, where \((\gamma^0)^{\dag}=\gamma^0\) and \((\gamma^i)^{\dag}=-(\gamma^i)\). The solution involves manipulating the gamma matrices and their indices, highlighting the importance of understanding their properties in the context of spinor algebra.

PREREQUISITES
  • Understanding of Dirac spinors and their properties
  • Familiarity with gamma matrices and their algebra
  • Knowledge of Hermitian conjugates in quantum mechanics
  • Basic grasp of tensor notation and index manipulation
NEXT STEPS
  • Study the properties of gamma matrices in detail, focusing on their anticommutation relations
  • Learn about the role of Dirac spinors in quantum field theory
  • Explore the implications of Hermitian conjugates in quantum mechanics
  • Investigate applications of spinor algebra in particle physics
USEFUL FOR

Students and researchers in theoretical physics, particularly those studying quantum mechanics and quantum field theory, will benefit from this discussion. It is especially relevant for those working with Dirac spinors and gamma matrices.

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Homework Statement


Show that \psi (\gamma^a\phi)=-(\gamma^a\phi)\psi

Homework Equations



Maybe \{\gamma^a, \gamma^b\}=\gamma^a\gamma^b+\gamma^b\gamma^a=2\eta^{ab}I

Perhaps also:

(\gamma^0)^{\dag}=\gamma^0 and (\gamma^i)^{\dag}=-(\gamma^i)

The Attempt at a Solution


The gammas are matrices so I guess we start with

\psi_{\mu}[(\gamma^a)^{\mu\nu}\phi_{\nu}]
=\psi_{\mu}[(((\gamma^a)^*)^{\dag})^{\nu\mu}\phi_{\nu}]
=-[(((\gamma^a)^*))^{\nu\mu}\psi_{\mu}]\phi_{\nu}

Which looks almost correct except the *, and also I'm not sure if I was supposed to assume that a can only refer to spatial indices, not the 0 which is equal to its hermitian conj, not minus it.

Thanks for any help
 
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