Feynman Diagrams and Pair Interactions

Henrik Bruus, Karsten Flensberg

Published Sep 2, 2004• 0 citations

Abstract

Abstract It is in the case of interacting particles and fields that the power of quantum field theory and Feynman diagrams really comes into play. In this chapter, we develop the Feynman diagram technique for a system of fermions with pair interactions. The primary example we will work with is a gas of fermions interacting through Coulomb interactions, but the technique is derived in a more general framework. In general, the Hamiltonian has two parts H = H 0 + W .

DOI: 10.1093/oso/9780198566335.003.0013

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