A short Introduction to Feynman Diagrams
نویسنده
چکیده
1 Kinetic terms A quantum field theory is defined by a Lagrangian. The first step is to define the fields. such that they represent particles. That means that there should be no terms with only one field present and all vacuum expectation values should have been subtracted The kinetic terms, those containing exactly two fields, are assumed to be diagonalized. This means that all terms with two fields are of one of the forms, for a field corresponding to a particle with mass m Field Lagrangian Field strength
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تاریخ انتشار 2014