Probabilities and signalling in quantum field theory
We present an approach to computing probabilities in quantum field theory for a wide class of source-detector models. The approach works directly with probabilities and not with squared matrix elements, and the resulting probabilities can be written in terms of expectation values of nested commutato...
| Main Authors: | , , |
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| Format: | Article |
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American Physical Society
2016
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| Online Access: | https://eprints.nottingham.ac.uk/35502/ |
| _version_ | 1848795093665841152 |
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| author | Dickinson, Robert Forshaw, Jeff Millington, Peter |
| author_facet | Dickinson, Robert Forshaw, Jeff Millington, Peter |
| author_sort | Dickinson, Robert |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | We present an approach to computing probabilities in quantum field theory for a wide class of source-detector models. The approach works directly with probabilities and not with squared matrix elements, and the resulting probabilities can be written in terms of expectation values of nested commutators and anti-commutators. We present results that help in the evaluation of these, including an expression for the vacuum expectation values of general nestings of commutators and anti-commutators in scalar field theory. This approach allows one to see clearly how faster-than-light signalling is prevented, because it leads to a diagrammatic expansion in which the retarded propagator plays a prominent role. We illustrate the formalism using the simple case of the much-studied Fermi two-atom problem. |
| first_indexed | 2025-11-14T19:26:37Z |
| format | Article |
| id | nottingham-35502 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:26:37Z |
| publishDate | 2016 |
| publisher | American Physical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-355022020-05-04T17:40:32Z https://eprints.nottingham.ac.uk/35502/ Probabilities and signalling in quantum field theory Dickinson, Robert Forshaw, Jeff Millington, Peter We present an approach to computing probabilities in quantum field theory for a wide class of source-detector models. The approach works directly with probabilities and not with squared matrix elements, and the resulting probabilities can be written in terms of expectation values of nested commutators and anti-commutators. We present results that help in the evaluation of these, including an expression for the vacuum expectation values of general nestings of commutators and anti-commutators in scalar field theory. This approach allows one to see clearly how faster-than-light signalling is prevented, because it leads to a diagrammatic expansion in which the retarded propagator plays a prominent role. We illustrate the formalism using the simple case of the much-studied Fermi two-atom problem. American Physical Society 2016-03-25 Article PeerReviewed Dickinson, Robert, Forshaw, Jeff and Millington, Peter (2016) Probabilities and signalling in quantum field theory. Physical Review D, 93 (6). 065054/1-065054/12. ISSN 2470-0010 http://journals.aps.org/prd/abstract/10.1103/PhysRevD.93.065054 doi:10.1103/PhysRevD.93.065054 doi:10.1103/PhysRevD.93.065054 |
| spellingShingle | Dickinson, Robert Forshaw, Jeff Millington, Peter Probabilities and signalling in quantum field theory |
| title | Probabilities and signalling in quantum field theory |
| title_full | Probabilities and signalling in quantum field theory |
| title_fullStr | Probabilities and signalling in quantum field theory |
| title_full_unstemmed | Probabilities and signalling in quantum field theory |
| title_short | Probabilities and signalling in quantum field theory |
| title_sort | probabilities and signalling in quantum field theory |
| url | https://eprints.nottingham.ac.uk/35502/ https://eprints.nottingham.ac.uk/35502/ https://eprints.nottingham.ac.uk/35502/ |