Little issue with relativistic quantum mechanics

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SUMMARY

The discussion centers on the application of Dirac's equation in momentum space, specifically the transformation from the position space representation to momentum space. The user initially presented the equation with an imaginary unit, but the response clarified that the imaginary unit does not appear in the momentum space version of Dirac's equation. The Gell-Mann matrices were mentioned, confirming their relevance in this context. The conclusion is that the user correctly transformed the equation, and the confusion arose from a typographical error in the source material.

PREREQUISITES
  • Understanding of Dirac's equation and its significance in quantum mechanics
  • Familiarity with momentum space representations in quantum field theory
  • Knowledge of Gell-Mann matrices and their role in particle physics
  • Basic grasp of complex numbers and their applications in quantum equations
NEXT STEPS
  • Study the derivation of Dirac's equation in both position and momentum space
  • Explore the implications of Gell-Mann matrices in quantum chromodynamics
  • Learn about the role of complex numbers in quantum mechanics
  • Investigate common typographical errors in quantum physics literature
USEFUL FOR

Physicists, graduate students in quantum mechanics, and researchers focusing on relativistic quantum field theory will benefit from this discussion.

StephvsEinst
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Hey!

I was working with Dirac's equation:
$$ ( i \hbar \gamma^\mu \partial_\mu - m ) \psi = 0, $$
and I found that if you work with a function that depends on the momentum, $$ \psi ( \mathbf{p} ), $$ you obtain:
$$ ( i \gamma \cdot \mathbf{p} + m ) \psi ( \mathbf{p} ) = 0. $$
The problem is that I can't figure out how did the imaginary number not disappear in the last equation. I tried to work with $$ p_\mu \rightarrow i \hbar \partial_\mu , $$
and I obtained the following:
$$ ( \gamma \cdot \mathbf{p} + m ) \psi ( \mathbf{p} ) = 0. $$
Help?
$$ --- $$
The $$ \gamma $$ are the Gell-Mann marices.
 
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The i is not there in the momentum space version of the Dirac equation. Wherever you took this from has a typo.
 
Orodruin said:
The i is not there in the momentum space version of the Dirac equation. Wherever you took this from has a typo.

Thanks for the answer. So I did it correctly?
 

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