Zobrazeno 1 - 10
of 120
pro vyhledávání: '"Brizuela, David"'
Autor:
Brizuela, David, Uria, Sara F.
The goal of this paper is to analyze the effects of the matter fields in the evolution of the Bianchi IX cosmology close to the singularity. Although the dynamics of this model is very involved, asymptotically, as the singularity is approached, it ca
Externí odkaz:
http://arxiv.org/abs/2407.17307
Autor:
Brizuela, David, Uria, Sara F.
We consider the Bianchi I geometry coupled to several species of comoving barotropic perfect fluids with a linear equation of state in the context of general relativity. The solution of the dynamics can be reduced to a quadrature, which can be explic
Externí odkaz:
http://arxiv.org/abs/2406.20070
We present a formalism to study linear perturbations of bimetric gravity on any spherically symmetric background, including dynamical spacetimes. The setup is based on the Gerlach-Sengupta formalism for general relativity. Each of the two background
Externí odkaz:
http://arxiv.org/abs/2402.15327
Autor:
Alonso-Bardaji, Asier, Brizuela, David
We provide a covariant framework to study singularity-free Lema\^itre-Tolman-Bondi spacetimes with effective corrections motivated by loop quantum gravity. We show that, as in general relativity, physically reasonable energy distributions lead to a c
Externí odkaz:
http://arxiv.org/abs/2312.15505
Autor:
Brizuela, David, Uria, Sara F.
We present a consistent formalism to describe the dynamics of hybrid systems with mixed classical and quantum degrees of freedom. The probability function of the system, which, in general, will be a combination of the classical distribution function
Externí odkaz:
http://arxiv.org/abs/2312.13946
Autor:
Alonso-Bardaji, Asier, Brizuela, David
We study covariant models for vacuum spherical gravity within a canonical setting. Starting from a general ansatz, we derive the most general family of Hamiltonian constraints that are quadratic in first-order and linear in second-order spatial deriv
Externí odkaz:
http://arxiv.org/abs/2310.12951
Publikováno v:
JCAP 03, 004 (2024)
Unlike general relativity, in bimetric gravity linear gravitational waves do not evolve as free fields. In this theory there are two types of tensor perturbations, whose interactions are inherited from non-trivial couplings between two dynamical metr
Externí odkaz:
http://arxiv.org/abs/2309.08536
According to general relativity, the generic early-universe dynamics is chaotic. Various quantum-gravity effects have been suggested that may change this behavior in different ways. Here, it is shown how key mathematical properties of the classical d
Externí odkaz:
http://arxiv.org/abs/2307.13040