Zobrazeno 1 - 10
of 31
pro vyhledávání: '"Adrià Delhom"'
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 4, Pp 1-10 (2021)
Abstract We consider the metric-affine formulation of bumblebee gravity, derive the field equations, and show that the connection can be written as Levi-Civita of a disformally related metric in which the bumblebee field determines the disformal part
Externí odkaz:
https://doaj.org/article/9ebf1529daaf4b5785df9ad3ebf60217
Autor:
Adrià Delhom
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 8, Pp 1-17 (2020)
Abstract We deal with the question of what it means to define a minimal coupling prescription in presence of torsion and/or non-metricity, carefully explaining while the naive substitution $$\partial \rightarrow \nabla $$ ∂→∇ introduces extra c
Externí odkaz:
https://doaj.org/article/0773579682dd4680889536262bf932bc
Autor:
Jose Beltrán Jiménez, Adrià Delhom
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 6, Pp 1-27 (2020)
Abstract We discuss the presence of ghostly instabilities for metric-affine theories constructed with higher order curvature terms. We mainly focus on theories containing only the Ricci tensor and show the crucial role played by the projective symmet
Externí odkaz:
https://doaj.org/article/51382015625c4d709b183b109410f1a6
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 5, Pp 1-11 (2020)
Abstract We show that the definition of proper time for Weyl-invariant space-times given by Perlick naturally extends to spaces with arbitrary non-metricity. We then discuss the relation between this generalized proper time and the Ehlers–Pirani–
Externí odkaz:
https://doaj.org/article/4b4938f5314342bdb28c7c5c5b36d746
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 4, Pp 1-14 (2020)
Abstract We show how minimally-coupled matter fields of arbitrary spin, when coupled to Ricci-based gravity theories, develop non-trivial effective interactions that can be treated perturbatively only below a characteristic high-energy scale $$\Lambd
Externí odkaz:
https://doaj.org/article/3a8dae65e7744c548b24cf59e1e4dc99
Publikováno v:
Physics Letters B, Vol 820, Iss , Pp 136479- (2021)
By using a novel technique that establishes a correspondence between general relativity and metric-affine theories based on the Ricci tensor, we are able to set stringent constraints on the free parameter of Born-Infeld gravity from the ones recently
Externí odkaz:
https://doaj.org/article/cab9c78b96774a02a628db594c4a855a
Publikováno v:
Physics Letters B, Vol 780, Iss , Pp 294-299 (2018)
Relaxing the Riemannian condition to incorporate geometric quantities such as torsion and non-metricity may allow to explore new physics associated with defects in a hypothetical space–time microstructure. Here we show that non-metricity produces o
Externí odkaz:
https://doaj.org/article/d4cbd2df5d47404f83e780a3796baf13
Autor:
Adrià Delhom I Latorre, García-Moreno, Gerardo, Hohmann, Manuel, Jiménez-Cano, Alejandro, Koivisto, Tomi S.
Publikováno v:
INSPIRE-HEP
In this work we study diffeomorphism-invariant metric-affine theories of gravity from the point of view of self-interacting field theories on top of Minkowski spacetime (or other background). We revise how standard metric theories couple to their own
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c8bd245aadb448570c0c89e860d7745f
Publikováno v:
Journal of High Energy Physics, Vol 2019, Iss 11, Pp 1-24 (2019)
Journal of High Energy Physics
Digital.CSIC. Repositorio Institucional del CSIC
instname
Repositório Institucional da UFRN
Universidade Federal do Rio Grande do Norte (UFRN)
instacron:UFRN
Journal of High Energy Physics
Digital.CSIC. Repositorio Institucional del CSIC
instname
Repositório Institucional da UFRN
Universidade Federal do Rio Grande do Norte (UFRN)
instacron:UFRN
We extend the correspondence between metric-affine Ricci-Based Gravity the- ories and General Relativity (GR) to the case in which the matter sector is represented by linear and nonlinear electromagnetic fields. This complements previous studies focu
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 79, Iss 10, Pp 1-9 (2019)
European Physical Journal
Digital.CSIC. Repositorio Institucional del CSIC
instname
European Physical Journal
Digital.CSIC. Repositorio Institucional del CSIC
instname
A Weyl structure is usually defined by an equivalence class of pairs $({\bf g}, \boldsymbol{\omega})$ related by Weyl transformations, which preserve the relation $\nabla {\bf g}=\boldsymbol{\omega}\otimes{\bf g}$, where ${\bf g}$ and $\boldsymbol{\o