nLab gauge fixing Lagrangian density

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Contents

Context

Algebraic Quantum Field Theory

algebraic quantum field theory (perturbative, on curved spacetimes, homotopical)

Introduction

Concepts

field theory:

Lagrangian field theory

quantization

quantum mechanical system, quantum probability

free field quantization

gauge theories

interacting field quantization

renormalization

Theorems

States and observables

Operator algebra

Local QFT

Perturbative QFT

Contents

Idea

In BV-BRST formalism a gauge fixing Lagrangian density (traditionally called a “gauge fixing fermion”) is a Lagrangian density L gf\mathbf{L}_{gf} whose Lagrangian function L gfL_{gf} is in degree -1 in a resolved BV-BRST complex whose Hamiltonian flow under the local antibracket is used to isomorph the complex into one that admits a degreewise covariant phase space. This is part of the process of “gauge fixing” in BV-BRST formalism.

This is called a “fermion” only because it has to sit in BV-BRST degree (-1). Besides this odd grading, it has nothing to do with the concept of fermions. Of course, if the field theory in question does contain fermion fields, then the “gauge fixing fermion” may depend on these.

Details

For details see at A first idea of quantum field theory the chapter Gauge fixing.

Last revised on December 14, 2017 at 17:42:18. See the history of this page for a list of all contributions to it.