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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Acknowledgments
The authors are supported by grant PID2020-118159GB-C41 funded by MCIN/AEI/10.13039/501100011033. G.C. thanks F. Briscese and R. Loll for useful discussions.
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Calcagni, G., Modesto, L. Path integral and conformal instability in nonlocal quantum gravity. J. High Energ. Phys. 2024, 277 (2024). https://doi.org/10.1007/JHEP07(2024)277
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DOI: https://doi.org/10.1007/JHEP07(2024)277