Browsing by Author "Haro Cases, Jaume"
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A note on gravitational dark matter production
Haro Cases, Jaume; Pan, Supriya (Multidisciplinary Digital Publishing Institute (MDPI), 2025-02)
Article
Open AccessDark matter, one of the fundamental components of the universe, has remained mysterious in modern cosmology and particle physics, and hence, this field is of utmost importance at the present moment. One of the foundational ... -
A review of quintessential inflation
Haro Cases, Jaume; Aresté Saló, Llibert (2021-12)
Article
Open AccessSome of the most important quintessential inflation scenarios, such as the Peebles–Vilenkin model, are described in detail. These models are able to explain the early- and late-time accelerated expansions of our universe, ... -
a-attractors in quintessential inflation motivated by supergravity
Aresté Saló, Llibert; Benistry, David; Guendelman, Eduardo I.; Haro Cases, Jaume (American Physical Society, 2021-06-15)
Article
Open AccessAn exponential kind of quintessential inflation potential motivated by supergravity is studied. This type belongs to the class of a-attractor models. The model was studied for the first time by Dimopoulos and Owen in [J. ... -
An extended matter bounce scenario: current status and challenges
Haro Cases, Jaume; Cai, Yi-Fu (2015-08-01)
Article
Open AccessAs an alternative to the paradigm of slow roll inflation, we propose an extended scenario of the matter bounce cosmology in which the Universe has experienced a quasi-matter contracting phase with a variable background ... -
Analytic formula to calculate the reheating temperature via gravitational particle production in smooth nonoscillating backgrounds
Haro Cases, Jaume; Aresté Saló, Llibert (American Physical Society, 2023-03-15)
Article
Open AccessWe present for smooth nonoscillating backgrounds an analytic formula which calculates the energy density of massive and massless particles created via gravitational particle production, thus giving the corresponding reheating ... -
ANÀLISI FUNCIONAL
Haro Cases, Jaume (Universitat Politècnica de Catalunya, 2007-06-29)
Exam
Restricted access to the UPC academic community -
Bouncing cosmologies in geometries with positively curved spatial sections
Haro Cases, Jaume (Elsevier, 2016-09-10)
Article
Open AccessBackground bouncing cosmologies, driven by a single scalar field, having a quasi-matter domination period during the contracting phase, i.e., depicting the so-called Matter Bounce Scenario, are reconstructed for cosmologies ... -
Bouncing cosmologies via modified gravity in the ADM formalism: Application to loop quantum cosmology
Haro Cases, Jaume; Amorós Torrent, Jaume (American Physical Society (APS), 2018-03-15)
Article
Open AccessWe consider the Arnowitt-Deser-Misner 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 modifying the gravitational ... -
Bouncing loop quantum cosmology from F(T) gravity
Amorós Torrent, Jaume; Haro Cases, Jaume; Odintsov, Sergei D. (2013-05)
Article
Open AccessThe big bang singularity could be understood as a breakdown of Einstein’s general relativity at very high energies. By adopting this viewpoint, other theories that implement Einstein cosmology at high energies might solve ... -
Bouncing loop quantum cosmology in Gauss-Bonnet gravity
Haro Cases, Jaume; Makarenko, A. M.; Myagky, A. N.; Odintsov, Sergei D.; Oikonomou, V. K. (American Physical Society, 2015-12-11)
Article
Open AccessWe develop an effective Gauss-Bonnet extension of loop quantum cosmology, by introducing holonomy corrections in modified F(G) theories of gravity. Within the context of our formalism, we provide a perturbative expansion ... -
Brane cosmology from observational surveys and its comparison with standard FRW cosmology
Astashenok, Artyom V.; Elizalde, Emilio; Haro Cases, Jaume; Odintsov, Sergei D.; Yurov, Artyom V. (2013-09)
Article
Restricted access - publisher's policySeveral simple dark energy models on the brane are investigated. They are compared with corresponding models in the frame of 4d Friedmann-Robertson-Walker cosmology. For constraining the parameters of the models considered, ... -
Bulk viscous quintessential inflation
Haro Cases, Jaume; Pan, Supriya (2018-04-01)
Article
Open AccessIn a spatially-flat Friedmann–Lemaître–Robertson–Walker universe, the incorporation of bulk viscous process in general relativity leads to an appearance of a nonsingular background of the universe that both at early and ... -
Calculation of the renormalized two-point function by adiabatic regularization
Haro Cases, Jaume (2010-11)
Article
Restricted access - publisher's policyWe calculate a renormalized two-point function using the adiabatic regularization method. We study the conformally and minimally coupled cases for massless and massive scalar fields in full detail. We reproduce previous ... -
Can quantum effects due to a massless conformally coupled field avoid gravitational singularities?
Haro Cases, Jaume (2012-04)
Article
Restricted access - publisher's policyUsing quantum corrections from massless fields conformally coupled to gravity, we study the possibility of avoiding singularities that appear in the flat Friedmann–Robertson–Walker model. We assume that the universe ... -
Cosmological perturbations in a class of fully covariant modified theories: application to models with the same background as standard LQC
Haro Cases, Jaume; Aresté Saló, Llibert; Elizalde, Emilio (Springer, 2018-09-01)
Article
Open AccessBouncing cosmologies are obtained by adding to the Einstein–Hilbert action a term of the form -g---vf(¿), with ¿ a scalar depending on the Hubble parameter only, not on its derivatives, and which is here shown to arise ... -
Cosmological solutions in spatially curved universes with adiabatic particle production
Aresté Saló, Llibert; Haro Cases, Jaume (2017-02-20)
Article
Open AccessWe perform a qualitative and thermodynamic study of two models when one takes into account adiabatic particle production. In the first one, there is a constant particle production rate, which leads to solutions depicting ... -
Cosmology intertwined: a review of the particle physics, astrophysics, and cosmology associated with the cosmological tensions and anomalies
Abdalla, Elcio; Abellan, Guillermo Franco; Aboubrahim, Amin; Agnello, Adriano; Akarsu, Özgür; Akrami, Yashar; Alestas, George; Aloni, Daniel; Amendola, Luca; Anchordoqui, Luis A.; Haro Cases, Jaume (2022-06)
Article
Open AccessThe standard Λ Cold Dark Matter (ΛCDM) cosmological model provides a good description of a wide range of astrophysical and cosmological data. However, there are a few big open questions that make the standard model look ... -
Different reheating mechanisms in quintessence inflation
Haro Cases, Jaume (American Physical Society (APS), 2019-02-11)
Article
Open AccessDifferent well-known ways to reheat the Universe, such as instant preheating, the creation of particles nearly or conformally coupled with gravity, or from the decay of products of a curvaton field, are revisited and ... -
Discrepancies between observational data and theoretical forecast in single field slow roll inflation
Amorós Torrent, Jaume; Haro Cases, Jaume (2016-09-09)
Article
Open AccessThe PLANCK collaboration has determined, or greatly constrained, values for the spectral parameters of the CMB radiation, namely the spectral index ns, its running as, the running of the running ßs, using a growing body ... -
Evolution and dynamics of a matter creation model
Pan, Supriya; Haro Cases, Jaume; Paliathanasis, A.; Slagter, R.J. (2016-05-01)
Article
Open AccessIn a flat Friedmann–Lemaître–Robertson–Walker (FLRW) geometry, we consider the expansion of the universe powered by the gravitationally induced ‘adiabatic’ matter creation. To demonstrate how matter creation works well ...