Oxford University Press eBooks

Quantum mechanics and elements of quantum field theory

Rodolfo Gambini, Jorge A. Pullin

Published Sep 22, 2011• 0 citations

Abstract

This chapter reviews elementary quantum mechanics, the introduction of a Hilbert space, quantum operators, and the promotion of Poisson brackets to commutators. It discusses the Harmonic oscillator, and introduces the number representation and creation and annihilation operators. The chapter then describes some elements of quantum field theory. It focuses on the free Klein-Gordon field as an example and shows that it can be viewed as a collection of Harmonic oscillators. The chapter then covers interacting quantum field theories, the interaction picture, Wick's theorem, and Feynman diagrams, and briefly considers renormalizability, the problems that arise in the case of gravity, and the asymptotic safety scenario.

DOI: 10.1093/acprof:oso/9780199590759.003.0006

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