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arXiv · 2304.09843

Quantum general covariance

Christian Gaß·José M. Gracia-Bondía·Karl-Henning Rehren
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Abstract

The structure of quantum interactions with fields of helicity two ("gravitons") is strongly constrained by three principles: positivity (Hilbert space), covariance, and locality of observables. To fulfil them simultaneously, some (non-observable) fields need to be non-local. We work with string-localized fields. The results then follow from the condition that entities closely related to observables, like the S-matrix, be local and string-independent. They in particular reproduce the interactions dictated by general covariance in classical field theory. Graviton-matter couplings are consistent only when the graviton self-interaction is taken into account as well.

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Christian Gaß, José M. Gracia-Bondía, Karl-Henning Rehren. 2023-04-12. Quantum general covariance. https://doi.org/10.1088/1361-6382%2Faceb2b

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