nLab vacuum diagram
Context
Vacua
Algebraic Quantum Field Theory
algebraic quantum field theory (perturbative, on curved spacetimes, homotopical)
Concepts
quantum mechanical system, quantum probability
interacting field quantization
Theorems
States and observables
Operator algebra
Local QFT
Perturbative QFT
Contents
Idea
A Feynman diagram without external edges is called a vacuum diagram.
For example the simplest vacuum diagram obtained from the electron-photon interaction in quantum electrodynamics is
In the computation of scattering amplitudes in a stable vacuum the contribution of the vacuum diagrams to the Feynman perturbation series cancels out.
For details see at S-matrix this section
Related concepts
Last revised on May 17, 2019 at 20:09:00. See the history of this page for a list of all contributions to it.