Apr 7 – 9, 2014
Royal Holloway, University of London
Europe/London timezone
Institute of Physics 2014 Joint High Energy Particle Physics and Astro Particle Physics Groups Annual Meeting

Manifest causality in QFT with sources and detectors

Apr 8, 2014, 6:00 PM
Room E (Windsor Building)

Room E

Windsor Building

contributed talk Particle Astrophysics, Current and Future Parallel 2E


Dr Peter Millington (University of Manchester and IPPP, Durham University)


In arXiv: 1312.3871, we introduce a way to compute transition amplitudes in quantum field theory for scatterings between sources and detectors, that is scatterings over finite space-time domains. Our amplitudes are manifestly causal, by which we mean that the source and detector are always linked by a connected chain of retarded propagators. We illustrate how these amplitudes may be obtained from a path-integral representation that closely resembles the in-in formalism of thermal field theory, introduced by Schwinger and Keldysh. Finally, we prove the tree-level equivalence of these amplitudes with the S-matrix and comment on potential deviations at the level of loops.

Primary author

Dr Peter Millington (University of Manchester and IPPP, Durham University)

Presentation materials