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arXiv · 1708.06239

Deducing Cosmological Observables from the S-matrix

S. P. Miao·T. Prokopec·R. P. Woodard
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Abstract

We study one loop quantum gravitational corrections to the long range force induced by the exchange of a massless scalar between two massive scalars. The various diagrams contributing to the flat space S-matrix are evaluated in a general covariant gauge and we show that dependence on the gauge parameters cancels at a point considerably {\it before} forming the full S-matrix, which is unobservable in cosmology. It is possible to interpret our computation as a solution to the effective field equations --- which could be done even in cosmology --- but taking account of quantum gravitational corrections from the source and from the observer.

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S. P. Miao, T. Prokopec, R. P. Woodard. 2017-08-21. Deducing Cosmological Observables from the S-matrix. https://doi.org/10.1103/physrevd.96.104029

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