Projection Operators for Energy and Spin

  • Walter Greiner


In practical calculations of quantum electrodynamic (QED) processes we will become acquainted with a technique of calculation which allows the simple treatment of complicated expressions; especially the calculation of traces of products of many γ matrices. It is based on a projection procedure, i.e. a method to project a spinor with a given sign of energy and fixed polarization out of a general wave function or a wave packet. The appropriate operators which achieve this are called projection operators.


Covariance PreP 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Walter Greiner
    • 1
    • 2
  1. 1.Institut für Theoretische PhysikJohann Wolfgang Goethe-Universität FrankfurtFrankfurt am MainGermany
  2. 2.Frankfurt am MainGermany

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