文档介绍：arXiv:hep-th/9505152 v1 25 May 1995
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INTRODUCTION TO QUANTUM FIELD THEORY
R. J. CREWTHER
Department of Physics and Mathematical Physics, University of Adelaide
Adelaide, . 5005, Australia
ABSTRACT
Even the uninitiated will know that Quantum Field Theory cannot be introduced
systematically in just four lectures. I try to give a reasonably connected outline
of part of it, from second quantization to the path-integral technique in Euclidean
space, where there is an immediate connection with the rules for Feynman diagrams
and the partition function of Statistical Mechanics.
1. Why Introduce Quantum Fields?
In ordinary quantum mechanics, displacement is an operator X, but time t is just
a parameter which labels Schr¨odinger state vectors or Heisenberg operators such as
X = X(t). This does not sit well with special relativity, whic