Late-time cosmological evolution in degenerate higher-order scalar-tensor models
| Autor: | Hamza Boumaza, Karim Noui, David Langlois |
|---|---|
| Přispěvatelé: | AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
velocity
cosmological model General relativity perturbation gravitation: model Perturbation (astronomy) alternative theories of gravity Parameter space 01 natural sciences photon: velocity Theoretical physics General Relativity and Quantum Cosmology Quadratic equation 0103 physical sciences Friedman model 010306 general physics dark energy Physics matter: nonrelativistic 010308 nuclear & particles physics Gravitational wave [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th] Degenerate energy levels gravitational radiation stability field theory: scalar Wavelength gravitation: scalar tensor evolution equation Dark energy [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] gravitation: higher-order [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] dark energy: equation of state |
| Zdroj: | Physical Review D Physical Review D, American Physical Society, 2020, 102 (2), pp.024018. ⟨10.1103/PhysRevD.102.024018⟩ Phys.Rev.D Phys.Rev.D, 2020, 102 (2), pp.024018. ⟨10.1103/PhysRevD.102.024018⟩ |
| ISSN: | 1550-7998 1550-2368 |
| Popis: | International audience; We study the late cosmological evolution, from the nonrelativistic matter dominated era to the dark energy era, in modified gravity models described by degenerate higher-order scalar-tensor (DHOST) theories. They represent the most general scalar-tensor theories propagating a single scalar degree of freedom and include Horndeski and beyond Horndeski theories. We provide the homogeneous evolution equations for any quadratic DHOST theory, without restricting ourselves to theories where the speed of gravitational waves coincides with that of light since the present constraints apply to wavelengths much smaller than cosmological scales. To illustrate the potential richness of the cosmological background evolution in these theories, we consider a simple family of shift-symmetric models, characterized by three parameters and compute the evolution of dark energy and of its equation of state. We also identify the regions in parameter space where the models are perturbatively stable. |
| Databáze: | OpenAIRE |
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