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arXiv · 2402.14785

Path integral and conformal instability in nonlocal quantum gravity

Gianluca Calcagni·Leonardo Modesto
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Abstract

We introduce the Lorentzian path integral of nonlocal quantum gravity. After introducing the functional measure, the Faddeev-Popov sector and the field correlators, we move to perturbation theory and describe Efimov analytic continuation of scattering amplitudes to Euclidean momenta and back to Lorentzian. We show that the conformal instability problem in the Euclidean path integral is solved by suitable gauge choices at the perturbative level. The three examples of Einstein gravity, Stelle gravity and nonlocal quantum gravity are given.

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Gianluca Calcagni, Leonardo Modesto. 2024-02-22. Path integral and conformal instability in nonlocal quantum gravity. https://doi.org/10.1007/jhep07(2024)277

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