Dirac equation continuity issue

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SUMMARY

The continuity of the Dirac equation is affirmed, but a concern arises regarding the momentum operator's Hermitian nature. The equation c α . (-i ℏ ∇ ψ) = c (i ℏ ∇ ψ†) . α indicates a sign change that contradicts the Hermitian property of the momentum operator. The discussion highlights the need for a proper understanding of the momentum operator's definition, particularly in relation to its Hermitian adjoint, which is defined as p = -iℏ∇ in the Schrödinger framework.

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raymo39
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So I definitely believe that the continuity of the Dirac equation holds, there is one thing that annoys me, which is that

[tex]c \alpha . (-i \hbar \nabla \psi ) = c (i \hbar \nabla \psi^\dagger ) . \alpha[/tex]

from the first part of the Dirac Hamiltonian
because the momentum operator should be Hermitian, but there is clearly a change of sign. I realize that the Hermitian conjugate of the spinor is now differently oriented, but shouldn't there be a change in ∇ such that its hermitian adjoint is negative itself to preserve the Hermitian nature of p?
I'm quite happy to try and prove this myself, but I am a bit lost as to where to start
 
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momentum operator is defined as in Schrödinger one,i.e. p=-ih-∇,which is hermitian as everyone knows.
 

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