nLab
scattering amplitude

Context

Physics

physics, mathematical physics, philosophy of physics

Surveys, textbooks and lecture notes


theory (physics), model (physics)

experiment, measurement, computable physics

Contents

Idea

In quantum field theory scattering amplitudes are the probability amplitudes for processes of scattering of fundamental particles (or fundamental strings etc.) off each other. The collection of scattering amplitudes forms the S-matrix. In perturbative quantum field theory its contributions may be labeled by Feynman diagrams, whence it is also called the Feynman perturbation series.

Of particular interest are vacuum amplitudes which are scattering amplitudes “where nothing externel scatters” hence for no incoming and no outgoing states. The 1-loop vacuum amplitudes are regularized traces over Feynman propagators. These are the incarnations of zeta functions, L-functions and eta functions in physics.

References

General

A good text is

intended to

bridge the gap between a standard course in quantum field theory and recent fascinating developments in the studies of on-shell scattering amplitudes.

Similarly

A historical overview of the development of on-shell methods/analytic methods is in

Analytic methods

See also at string theory results applied elsewhere and at motivic multiple zeta values.

In super Yang-Mills theory

In super Yang-Mills theory (and there in particular in the planar limit of N=4 D=4 super Yang-Mills theory) scattering amplitudes enjoy special symmetry properties, some of which can be used to extract information about scattering amplitudes in non-supersymmetric theories (see also at amplituhedron):

In string theory and higher supergravity

  • Wieland Staessens, Bert Vercnocke, Lectures on Scattering Amplitudes in String Theory (arXiv:1011.0456)

  • Michael Green, Properties of low energy graviton scattering amplitudes, June 2010 (pdf)

For more see at string scattering amplitude.

Motivic structure

Motivic structures in scattering amplitudes (see at motives in physics) are discussed for instance in

  • John Golden, Alexander B. Goncharov, Marcus Spradlin, Cristian Vergu, Anastasia Volovich, Motivic Amplitudes and Cluster Coordinates (arXiv:1305.1617)

See also the references at period.

Revised on September 13, 2017 11:29:35 by Urs Schreiber (77.56.177.247)