252 citations · 1.5k across the 51 of their papers we have counts for
45 papers · 1 filter
Accelerating scaling solutions from dark matter particle creation
Sudip Halder, Jaume de Haro, Supriya Pan +3
This article opens new window to obtain accelerating scaling attractors without any need of dark energy. We study cosmological dynamics in a two-fluid system where pressureless dar…
A dynamical approach to General Relativity based on proper time
Jaume de Haro
This work places the invariant at the center of the gravitational interaction, interpreting it not as a purely geometric object but as the differential of proper time, endow…
Novikov Coordinates and the Physical Description of Gravitational Collapse
Jaume de Haro
We show that the Novikov coordinates can be obtained in a direct and physically transparent way from the radial geodesics of massive particles with negative energy in the Schwarzsc…
On the Geometric Meaning of General Relativity and the Foundations of Newtonian Cosmology
Jaume de Haro, Emilio Elizalde
The geometric foundations of General Relativity are revisited, with particular attention to its gauge invariance, as a key to understanding the true nature of spacetime. Beyond the…
On the perturbed Friedmann equations in Newtonian Gauge
Jaume de Haro, Emilio Elizalde, Supriya Pan
Based on the Newtonian mechanics, in this article, we present a heuristic derivation of the Friedmann equations, providing an intuitive foundation for these fundamental relations i…
Gravitational reheating formulas and bounds in oscillating backgrounds
Jaume de Haro, Llibert Aresté Saló, Supriya Pan
In this article we calculate the reheating temperature in the cosmological scenarios where heavy scalar particles are gravitationally produced, due to a conformally coupled interac…
Relations between Newtonian and relativistic cosmology
Jaume de Haro
We start with the cosmic Friedmann equations, where we adopt a novel perspective rooted in a Lagrangian formulation grounded in Newtonian mechanics and the first law of thermodynam…
Phase space analysis of sign-shifting interacting dark energy models
Sudip Halder, Jaume de Haro, Tapan Saha +1
The theory of non-gravitational interaction between a pressure-less dark matter (DM) and dark energy (DE) is a phenomenologically rich cosmological domain which has received magnif…
Finite-time Cosmological Singularities and the Possible Fate of the Universe
Jaume de Haro, Shin'ichi Nojiri, S. D. Odintsov +2
Singularities in any physical theory are either remarkable indicators of the unknown underlying fundamental theory, or indicate a change in the description of the physical reality.…
Reheating formulas in Quintessential Inflation via Gravitational Particle Production
Jaume de Haro
We calculate the reheating temperature in scenarios where heavy particles are gravitationally produced during a phase transition. We explore two distinct situations: the decay of t…
Reheating constraints in Instant Preheating
Jaume de Haro
We use Instant Preheating as a mechanism to reheat the universe when its evolution is modeled by a non-oscillating background. Once we obtain the reheating temperature, we calculat…
An analytic formula to calculate the reheating temperature via gravitational particle production
Jaume de Haro, Llibert Aresté Saló
We present for smooth non-oscillating backgrounds an analytic formula which calculates the energy density of massive and massless particles created via gravitational particle produ…
The problem of calculating the -Bogoliubov coefficient in Non-Oscillating models
Jaume de Haro, Llibert Aresté Saló
The calculation of the Bogoliubov coefficients is a key piece to obtain the reheating temperature of the Universe. In all cases this calculation is performed either in toy models w…
Gravitational particle production of superheavy massive particles in Quintessential Inflation II: -attractors
Llibert Aresté Saló, Jaume de Haro
We compute the gravitational production of conformally coupled superheavy particles during the phase transition from the end of inflation to the beginning of kination for -attra…
A review of Quintessential Inflation
Jaume de Haro, Llibert Aresté Saló
We compute numerically the reheating temperature due to the gravitational production of conformally coupled superheavy particles during the phase transition from the end of inflati…
Understanding the phenomenology of interacting dark energy scenarios and their theoretical bounds
Supriya Pan, Jaume de Haro, Weiqiang Yang +1
Non-gravitational interaction between dark matter and dark energy has been considered in a spatially flat Friedmann-Lemaître-Robertson-Walker (FLRW) universe. The interaction rate…
Understanding gravitational particle production in quintessential inflation
Jaume de Haro, Supriya Pan, Llibert Aresté Saló
The diagonalization method, introduced by a group of Russian scientists at the beginning of seventies, is used to compute the energy density of superheavy massive particles produce…
Limiting curvature mimetic gravity and its relation to Loop Quantum Cosmology
Jaume de Haro, Llibert Aresté Saló, Supriya Pan
Considering as usual that the underlying geometry of our universe is well described by the spatially flat Friedmann-Lemaitre-Robertson-Walker line element, we review how the backgr…
Viable Inflationary Evolution from Loop Quantum Cosmology Scalar-Tensor Theory
Jaume de Haro, S. D. Odintsov, V. K. Oikonomou
In this work we construct a bottom-up reconstruction technique for Loop Quantum Cosmology scalar-tensor theories, from the observational indices. Particularly, the reconstruction t…
Note on bouncing backgrounds
Jaume de Haro, Supriya Pan
The theory of inflation is one of the fundamental and revolutionary developments of modern cosmology that became able to explain many issues of early universe in the context of the…
Bouncing cosmologies via modified gravity in the ADM formalism: Application to Loop Quantum Cosmology
Jaume de Haro, Jaume Amorós
We consider the ADM formalism as a tool to build bouncing cosmologies. In this approach, the foliation of the spacetime has to be fixed in order to go beyond General Relativity mod…
Viscous Cosmology for Early- and Late-Time Universe
Iver Brevik, Øyvind Grøn, Jaume de Haro +2
From a hydrodynamicist's point of view the inclusion of viscosity concepts in the macroscopic theory of the cosmic fluid would appear most natural, as an ideal fluid is after all a…
Reheating constraints in quintessential inflation
Jaume de Haro, Llibert Aresté Saló
We study the consequences of reheating in quintessential inflation. From simple inflationary quintessential models introduced in cite{hap, hap2}, we show that when the reheating is…
Qualitative study in Loop Quantum Cosmology
Llibert Aresté Saló, Jaume Amorós, Jaume de Haro
This work contains a detailed qualitative analysis, in General Relativity and in Loop Quantum Cosmology, of the dynamics in the associated phase space of a scalar field minimally c…