557 citations · 2.3k across the 25 of their papers we have counts for
26 papers
Non-linear structure formation with elastic interactions in the dark sector
Jose Beltrán Jiménez, David Figueruelo, David F. Mota +1
Cosmological models where dark matter interacts with dark energy via a pure momentum transfer and with no energy exchange (i.e. elastic) provide compelling scenarios for addressing…
Modified Gravity and Cosmology: An Update by the CANTATA Network
Emmanuel N. Saridakis, Ruth Lazkoz, Vincenzo Salzano +50
General Relativity and the CDM framework are currently the standard lore and constitute the concordance paradigm. Nevertheless, long-standing open theoretical issues, as well as…
Born-Infeld Gravity: Constraints from Light-by-Light Scattering and an Effective Field Theory Perspective
Jose Beltrán Jiménez, Adrià Delhom, Gonzalo J. Olmo +1
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 constrain…
The miniJPAS survey: a preview of the Universe in 56 colours
S. Bonoli, A. Marín-Franch, J. Varela +166
The Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) will soon start to scan thousands of square degrees of the northern extragalactic sky with a unique…
Anisotropic deformations in a class of projectively-invariant metric-affine theories of gravity
Jose Beltrán Jiménez, Daniel de Andrés, Adrià Delhom
Among the general class of metric-affine theories of gravity, there is a special class conformed by those endowed with a projective symmetry. Perhaps the simplest manner to realise…
On cosmological signatures of baryons-dark energy elastic couplings
Jose Beltrán Jiménez, Dario Bettoni, David Figueruelo +1
We consider a scenario where dark energy and baryons are dynamically coupled without any energy transfer. In this scenario, the background cosmology is unaffected and, at the pertu…
Minkowski space in gravity
Jose Beltran Jimenez, Alexey Golovnev, Tomi Koivisto +1
The full set of solutions of gravity with the Minkowski metric is considered in this note. At the 4-th order in perturbations around the trivial tetrad solution, a new mode…
Charged Dark Matter and the tension
Jose Beltrán Jiménez, Dario Bettoni, Philippe Brax
We consider cosmological models where dark matter is charged under a dark Abelian gauge field. This new interaction is repulsive and competes with gravity on large scales and in th…
Probing cosmological fields with gravitational wave oscillations
Jose Beltrán Jiménez, Jose María Ezquiaga, Lavinia Heisenberg
Gravitational wave (GW) oscillations occur whenever there are additional tensor modes interacting with the perturbations of the metric coupled to matter. These extra modes can aris…
Revisiting the Stability of Quadratic Poincaré Gauge Gravity
Jose Beltrán Jiménez, Francisco José Maldonado Torralba
Poincaré gauge theories provide an approach to gravity based on the gauging of the Poincaré group, whose homogeneous part generates curvature while the translational sector gives r…
Non-Linear Obstructions for Consistent New General Relativity
Jose Beltrán Jiménez, Konstantinos F. Dialektopoulos
We revisit the field content and consistency of the New General Relativity family of theories. These theories are constructed in a geometrical framework with a flat and metric-comp…
Cosmology in geometry
Jose Beltrán Jiménez, Lavinia Heisenberg, Tomi Sebastian Koivisto +1
The universal character of the gravitational interaction provided by the equivalence principle motivates a geometrical description of gravity. The standard formulation of General R…
On structure formation from a small-scales-interacting dark sector
Mahnaz Asghari, Jose Beltran Jimenez, Shahram Khosravi +1
We consider a cosmological model with an interaction between dark matter and dark energy which leaves the background cosmology unaffected and only affects the evolution of the pert…
Limits on the anomalous speed of gravitational waves from binary pulsars
Hermano Velten, Jose Beltrán Jiménez, Federico Piazza
A large class of modified theories of gravity used as models for dark energy predict a propagation speed for gravitational waves which can differ from the speed of light. This diff…
Generalized multi-Proca fields
Jose Beltrán Jiménez, Lavinia Heisenberg
We extend previous results on healthy derivative self-interactions for a Proca field to the case of a set of massive vector fields. We obtain non-gauge invariant derivative self-in…
Derivative self-interactions for a massive vector field
Jose Beltrán Jiménez, Lavinia Heisenberg
In this work we revisit the construction of theories for a massive vector field with derivative self-interactions such that only the 3 desired polarizations corresponding to a Proc…
Beyond CDM: Problems, solutions, and the road ahead
Philip Bull, Yashar Akrami, Julian Adamek +37
Despite its continued observational successes, there is a persistent (and growing) interest in extending cosmology beyond the standard model, CDM. This is motivated by a range o…
Spacetimes with vector distortion: Inflation from generalised Weyl geometry
Jose Beltrán Jiménez, Tomi S. Koivisto
Spacetime with general linear vector distortion is introduced. Thus, the torsion and the nonmetricity of the affine connection are assumed to be proportional to a vector field (and…
Tensor perturbations in a general class of Palatini theories
Jose Beltrán Jiménez, Lavinia Heisenberg, Gonzalo J. Olmo
We study a general class of gravitational theories formulated in the Palatini approach and derive the equations governing the evolution of tensor perturbations. In the absence of t…
The Zakharov-Kuznetsov equation in weighted Sobolev spaces
Eddye Bustamante, José Jiménez, Jorge Mejía
In this work we consider the initial value problem (IVP) associated to the two dimensional Zakharov-Kuznetsov equation $$\left. \begin{array}{rl} u_t+\partial_x^3 u+\partial_x \par…
Infrared lessons for ultraviolet gravity: the case of massive gravity and Born-Infeld
Jose Beltrán Jiménez, Lavinia Heisenberg, Gonzalo J. Olmo
We generalize the ultraviolet sector of gravitation via a Born-Infeld action using lessons from massive gravity. The theory contains all of the elementary symmetric polynomials and…
The Cauchy problem for a fifth order KdV equation in weighted Sobolev spaces
Eddye Bustamante, José Jiménez, Jorge Mejía
In this work we study the initial value problem (IVP) for the fifth order KdV equations, \begin{align*} \partial_{t}u+\partial_{x}^{5}u+u^k\partial_{x}u=0,\text{} & \quad x,t\in \m…
Cosmology with a Continuous Tower of Scalar Fields
Jose Beltrán Jiménez, David F. Mota, Paulo Santos
We study the cosmological evolution for a universe in the presence of a continuous tower of massive scalar fields which can drive the current phase of accelerated expansion of the…
Screening Vector Field Modifications of General Relativity
Jose Beltrán Jiménez, André Luís Delvas Fróes, David F. Mota
A screening mechanism for conformal vector-tensor modifications of general relativity is proposed. The conformal factor depends on the norm of the vector field and makes the field…