Revisiting the minimum length in the Schwinger-Keldysh formalism

Abstract

The existence of a minimum length in quantum gravity is investigated by computing the in-in expectation value of the proper distance in the Schwinger-Keldysh formalism. No minimum geometrical length is found for arbitrary gravitational theories to all orders in perturbation theory. Using non-perturbative techniques, we also show that neither the conformal sector of general relativity nor higher-derivative gravity features a minimum length. A minimum length scale, on the other hand, seems to always be present when one considers in-out amplitudes, from which one could extract the energy scale of scattering processes.

arXiv commentVersion accepted for publication

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Cited by in corpus (4)

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• When gravitational decoupling and quantum gravity (re)unite
• Compact sources and cosmological horizons in lower dimensional bootstrapped Newtonian gravity