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Author Olmo, G.J.; Rubiera-Garcia, D.
Title Brane-world and loop cosmology from a gravity-matter coupling perspective Type Journal Article
Year 2015 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 740 Issue Pages 73-79
Keywords Modified gravity; Palatini formalism; f(R) theories; Gravity-matter coupling; Quadratic cosmology
Abstract We show that the effective brane-world and the loop quantum cosmology background expansion histories can be reproduced from a modified gravity perspective in terms of an f (R) gravity action plus a g(R) term non-minimally coupled with the matter Lagrangian. The reconstruction algorithm that we provide depends on a free function of the matter density that must be specified in each case and allows to obtain analytical solutions always. In the simplest cases, the function f (R) is quadratic in the Ricci scalar, R, whereas g(R) is linear. Our approach is compared with recent results in the literature. We show that working in the Palatini formalism there is no need to impose any constraint that keeps the equations second order, which is a key requirement for the successful implementation of the reconstruction algorithm.
Address [Olmo, Gonzalo J.] Univ Valencia, CSIC, Ctr Mixto, Dept Fis Teor, E-46100 Valencia, Spain, Email: gonzalo.olmo@csic.es;
Corporate Author Thesis
Publisher (up) Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000347046200013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2099
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Author Pena-Garay, C.; Verde, L.; Jimenez, R.
Title Neutrino footprint in large scale structure Type Journal Article
Year 2017 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe
Volume 15 Issue Pages 31-34
Keywords Cosmology; Neutrinos; Large scale structure
Abstract Recent constrains on the sum of neutrino masses inferred by analyzing cosmological data, show that detecting a non-zero neutrino mass is within reach of forthcoming cosmological surveys. Such a measurement will imply a direct determination of the absolute neutrino mass scale. Physically, the measurement relies on constraining the shape of the matter power spectrum below the neutrino free streaming scale: massive neutrinos erase power at these scales. However, detection of a lack of small-scale power from cosmological data could also be due to a host of other effects. It is therefore of paramount importance to validate neutrinos as the source of power suppression at small scales. We show that, independent on hierarchy, neutrinos always show a footprint on large, linear scales; the exact location and properties are fully specified by the measured power suppression (an astrophysical measurement) and atmospheric neutrinos mass splitting (a neutrino oscillation experiment measurement). This feature cannot be easily mimicked by systematic uncertainties in the cosmological data analysis or modifications in the cosmological model. Therefore the measurement of such a feature, up to 1% relative change in the power spectrum for extreme differences in the mass eigenstates mass ratios, is a smoking gun for confirming the determination of the absolute neutrino mass scale from cosmological observations. It also demonstrates the synergy between astrophysics and particle physics experiments.
Address [Verde, Licia; Jimenez, Raul] Univ Barcelona, ICREA, Marti & Franques 1, E-08028 Barcelona, Spain, Email: liciaverde@gmail.com
Corporate Author Thesis
Publisher (up) Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2212-6864 ISBN Medium
Area Expedition Conference
Notes WOS:000401825700003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3138
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Author Beltran Jimenez, J.; Heisenberg, L.; Olmo, G.J.; Rubiera-Garcia, D.
Title Born-Infeld inspired modifications of gravity Type Journal Article
Year 2018 Publication Physics Reports Abbreviated Journal Phys. Rep.
Volume 727 Issue Pages 1-129
Keywords Born-Infeld gravity; Astrophysics; Black holes; Cosmology; Early universe; Compact objects; Singularities
Abstract General Relativity has shown an outstanding observational success in the scales where it has been directly tested. However, modifications have been intensively explored in the regimes where it seems either incomplete or signals its own limit of validity. In particular, the breakdown of unitarity near the Planck scale strongly suggests that General Relativity needs to be modified at high energies and quantum gravity effects are expected to be important. This is related to the existence of spacetime singularities when the solutions of General Relativity are extrapolated to regimes where curvatures are large. In this sense, Born-Infeld inspired modifications of gravity have shown an extraordinary ability to regularise the gravitational dynamics, leading to non-singular cosmologies and regular black hole spacetimes in a very robust manner and without resorting to quantum gravity effects. This has boosted the interest in these theories in applications to stellar structure, compact objects, inflationary scenarios, cosmological singularities, and black hole and wormhole physics, among others. We review the motivations, various formulations, and main results achieved within these theories, including their observational viability, and provide an overview of current open problems and future research opportunities.
Address [Beltran Jimenez, Jose] Univ Autonoma Madrid, CSIC, Inst Fis Teor, E-28049 Madrid, Spain, Email: jose.beltran@uam.es;
Corporate Author Thesis
Publisher (up) Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1573 ISBN Medium
Area Expedition Conference
Notes WOS:000425482900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3497
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Author Consiglio, R.; de Salas, P.F.; Mangano, G.; Miele, G.; Pastor, S.; Pisanti, O.
Title PArthENoPE reloaded Type Journal Article
Year 2018 Publication Computer Physics Communications Abbreviated Journal Comput. Phys. Commun.
Volume 233 Issue Pages 237-242
Keywords Primordial nucleosynthesis; Cosmology; Neutrino physics
Abstract We describe the main features of a new and updated version of the program PArthENoPE, which computes the abundances of light elements produced during Big Bang Nucleosynthesis. As the previous first release in 2008, the new one, PArthENoPE2.0, is publicly available and distributed from the code site, http://parthenope.na.infn.it . Apart from minor changes, which will be also detailed, the main improvements are as follows. The powerful, but not freely accessible, NAG routines have been substituted by ODEPACK libraries, without any significant loss in precision. Moreover, we have developed a Graphical User Interface (GUI) which allows a friendly use of the code and a simpler implementation of running for grids of input parameters. New Version program summary Program Title: PArthENoPE2.0 Program Files doi : http://dx.doi.org/10.17632/wvgr7d8yt9.1 Licensing provisions: GPLv3 Programming language: Fortran 77 and Python Supplementary material: User Manual available on the web page http://parthenope.na.infn.it Journal reference of previous version: Comput. Phys. Commun. 178 (2008) 956 971 Does the new version supersede the previous version?: Yes Reasons for the new version: Make the code more versatile and user friendly Summary of revisions: (1) Publicly available libraries (2) GUI for configuration Nature of problem: Computation of yields of light elements synthesized in the primordial universe Solution method: Livermore Solver for Ordinary Differential Equations (LSODE) for stiff and nonstiff systems
Address [Consiglio, R.; Miele, G.; Pisanti, O.] Univ Napoli Federico II, Dipartimento Fis E Pancini, Via Cintia, I-80126 Naples, Italy, Email: pisanti@na.infn.it
Corporate Author Thesis
Publisher (up) Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0010-4655 ISBN Medium
Area Expedition Conference
Notes WOS:000444667100020 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3729
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Author Villanueva-Domingo, P.; Mena, O.; Palomares-Ruiz, S.
Title A Brief Review on Primordial Black Holes as Dark Matter Type Journal Article
Year 2021 Publication Frontiers in Astronomy and Space Sciences Abbreviated Journal Front. Astron. Space Sci.
Volume 8 Issue Pages 681084 - 10pp
Keywords primordial black holes; dark matter; cosmology; accretion; 21 cm cosmology; gravitational waves; cosmic microwave background; microlensing
Abstract Primordial black holes (PBHs) represent a natural candidate for one of the components of the dark matter (DM) in the Universe. In this review, we shall discuss the basics of their formation, abundance and signatures. Some of their characteristic signals are examined, such as the emission of particles due to Hawking evaporation and the accretion of the surrounding matter, effects which could leave an impact in the evolution of the Universe and the formation of structures. The most relevant probes capable of constraining their masses and population are discussed.
Address [Villanueva-Domingo, Pablo; Mena, Olga; Palomares-Ruiz, Sergio] CSIC Univ Valencia, Inst Fis Corpuscular IFIC, Paterna, Spain, Email: pablo.villanueva.domingo@gmail.com
Corporate Author Thesis
Publisher (up) Frontiers Media Sa Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-987x ISBN Medium
Area Expedition Conference
Notes WOS:000660081700001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4852
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