On the resilience of the gravitational variational principle under renormalization

Abstract A well-defined variational principle for gravitational actions typically requires to cancel boundary terms produced by the variation of the bulk action with a suitable set of boundary counterterms. This can be achieved by carefully balancing the coefficients multiplying the bulk operators w...

Full description

Bibliographic Details
Main Authors: Giulio Neri, Stefano Liberati
Format: Article
Language:English
Published: SpringerOpen 2023-10-01
Series:Journal of High Energy Physics
Subjects:
Online Access:https://doi.org/10.1007/JHEP10(2023)054
_version_ 1797341410833203200
author Giulio Neri
Stefano Liberati
author_facet Giulio Neri
Stefano Liberati
author_sort Giulio Neri
collection DOAJ
description Abstract A well-defined variational principle for gravitational actions typically requires to cancel boundary terms produced by the variation of the bulk action with a suitable set of boundary counterterms. This can be achieved by carefully balancing the coefficients multiplying the bulk operators with those multiplying the boundary ones. A typical example of this construction is the Gibbons-Hawking-York boundary action that needs to be added to the Einstein-Hilbert one in order to have a well-defined metric variation for General Relativity with Dirichlet boundary conditions. Quantum fluctuations of matter fields lead to a renormalization of these coefficients which may or may not preserve this balance. Indeed, already at the level of General Relativity, the resilience of the matching between bulk and boundary constants is far from obvious and it is anyway incomplete given that matter generically induces quadratic curvature operators. We investigate here the resilience of the matching of higher-order couplings upon renormalization by a non-minimally coupled scalar field and show that a problem is present. Even though we do not completely solve the latter, we show that it can be greatly ameliorated by a wise splitting between dynamical and topological contributions. Doing so, we find that the bulk-boundary matching is preserved up to a universal term (present for any Weyl invariant matter field content), whose nature and possible cancellation we shall discuss in the end.
first_indexed 2024-03-08T10:17:42Z
format Article
id doaj.art-5c62d6b242ef4f1c8aee645a256636df
institution Directory Open Access Journal
issn 1029-8479
language English
last_indexed 2024-03-08T10:17:42Z
publishDate 2023-10-01
publisher SpringerOpen
record_format Article
series Journal of High Energy Physics
spelling doaj.art-5c62d6b242ef4f1c8aee645a256636df2024-01-28T12:14:55ZengSpringerOpenJournal of High Energy Physics1029-84792023-10-0120231012810.1007/JHEP10(2023)054On the resilience of the gravitational variational principle under renormalizationGiulio Neri0Stefano Liberati1International School for Advanced Studies (SISSA)International School for Advanced Studies (SISSA)Abstract A well-defined variational principle for gravitational actions typically requires to cancel boundary terms produced by the variation of the bulk action with a suitable set of boundary counterterms. This can be achieved by carefully balancing the coefficients multiplying the bulk operators with those multiplying the boundary ones. A typical example of this construction is the Gibbons-Hawking-York boundary action that needs to be added to the Einstein-Hilbert one in order to have a well-defined metric variation for General Relativity with Dirichlet boundary conditions. Quantum fluctuations of matter fields lead to a renormalization of these coefficients which may or may not preserve this balance. Indeed, already at the level of General Relativity, the resilience of the matching between bulk and boundary constants is far from obvious and it is anyway incomplete given that matter generically induces quadratic curvature operators. We investigate here the resilience of the matching of higher-order couplings upon renormalization by a non-minimally coupled scalar field and show that a problem is present. Even though we do not completely solve the latter, we show that it can be greatly ameliorated by a wise splitting between dynamical and topological contributions. Doing so, we find that the bulk-boundary matching is preserved up to a universal term (present for any Weyl invariant matter field content), whose nature and possible cancellation we shall discuss in the end.https://doi.org/10.1007/JHEP10(2023)054Classical Theories of GravityRenormalization and RegularizationRenormalization Group
spellingShingle Giulio Neri
Stefano Liberati
On the resilience of the gravitational variational principle under renormalization
Journal of High Energy Physics
Classical Theories of Gravity
Renormalization and Regularization
Renormalization Group
title On the resilience of the gravitational variational principle under renormalization
title_full On the resilience of the gravitational variational principle under renormalization
title_fullStr On the resilience of the gravitational variational principle under renormalization
title_full_unstemmed On the resilience of the gravitational variational principle under renormalization
title_short On the resilience of the gravitational variational principle under renormalization
title_sort on the resilience of the gravitational variational principle under renormalization
topic Classical Theories of Gravity
Renormalization and Regularization
Renormalization Group
url https://doi.org/10.1007/JHEP10(2023)054
work_keys_str_mv AT giulioneri ontheresilienceofthegravitationalvariationalprincipleunderrenormalization
AT stefanoliberati ontheresilienceofthegravitationalvariationalprincipleunderrenormalization