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Author Agius, D.; Essig, R.; Gaggero, D.; Scarcella, F.; Suczewski, G.; Valli, M.
Title Feedback in the dark: a critical examination of CMB bounds on primordial black holes Type Journal Article
Year 2024 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal (down) J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 003 - 36pp
Keywords accretion; cosmological parameters from CMBR; dark matter theory; primordial black holes
Abstract If present in the early universe, primordial black holes (PBHs) would have accreted matter and emitted high-energy photons, altering the statistical properties of the Cosmic Microwave Background (CMB). This mechanism has been used to constrain the fraction of dark matter that is in the form of PBHs to be much smaller than unity for PBH masses well above one solar mass. Moreover, the presence of dense dark matter mini -halos around the PBHs has been used to set even more stringent constraints, as these would boost the accretion rates. In this work, we critically revisit CMB constraints on PBHs taking into account the role of the local ionization of the gas around them. We discuss how the local increase in temperature around PBHs can prevent the dark matter mini -halos from strongly enhancing the accretion process, in some cases significantly weakening previously derived CMB constraints. We explore in detail the key ingredients of the CMB bound and derive a conservative limit on the cosmological abundance of massive PBHs.
Address [Agius, Dominic] Univ Valencia, CSIC, Inst Fis Corpuscular, C Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: dominic.agius@ific.uv.es;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:001262242300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6187
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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 (down) 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 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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Author Galli, P.; Ortin, T.; Perz, J.; Shahbazi, C.S.
Title From supersymmetric to non-supersymmetric black holes Type Journal Article
Year 2012 Publication Fortschritte der Physik-Progress of Physics Abbreviated Journal (down) Fortschritte Phys.-Prog. Phys.
Volume 60 Issue 9-10 Pages 1026-1029
Keywords Black holes; supergravity
Abstract Methods similar to those used for obtaining supersymmetric black hole solutions can be employed to find also non-supersymmetric solutions. We briefly review some of them, with the emphasis on the non-extremal deformation ansatz of [1].
Address [Ortin, Tomas; Perz, Jan; Shahbazi, C. S.] Inst Fis Teor UAM CSIC, Madrid 28049, Spain, Email: Pietro.Galli@ific.uv.es;
Corporate Author Thesis
Publisher Wiley-V C H Verlag Gmbh Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0015-8208 ISBN Medium
Area Expedition Conference
Notes WOS:000308301500012 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1151
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Author Olmo, G.J.; Rubiera-Garcia, D.; Sanchez-Puente, A.
Title Impact of curvature divergences on physical observers in a wormhole space-time with horizons Type Journal Article
Year 2016 Publication Classical and Quantum Gravity Abbreviated Journal (down) Class. Quantum Gravity
Volume 33 Issue 11 Pages 115007 - 12pp
Keywords Singularities; black holes; metric-affine geometry
Abstract The impact of curvature divergences on physical observers in a black hole space-time, which, nonetheless, is geodesically complete is investigated. This space-time is an exact solution of certain extensions of general relativity coupled to Maxwell's electrodynamics and, roughly speaking, consists of two Reissner-Nordstrom (or Schwarzschild or Minkowski) geometries connected by a spherical wormhole near the center. We find that, despite the existence of infinite tidal forces, causal contact is never lost among the elements making up the observer. This suggests that curvature divergences may not be as pathological as traditionally thought.
Address [Olmo, Gonzalo J.; Sanchez-Puente, A.] Univ Valencia, CSIC, Ctr Mixto, Dept Fis Teor, E-46100 Valencia, Spain, Email: gonzalo.olmo@csic.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0264-9381 ISBN Medium
Area Expedition Conference
Notes WOS:000377442000010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2728
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Author Olmo, G.J.; Rubiera-Garcia, D.; Sanchez-Puente, A.
Title Accelerated observers and the notion of singular spacetime Type Journal Article
Year 2018 Publication Classical and Quantum Gravity Abbreviated Journal (down) Class. Quantum Gravity
Volume 35 Issue 5 Pages 055010 - 18pp
Keywords general relativity; geodesic behaviour; black holes; spacetime singularities; modified theories of gravity
Abstract Geodesic completeness is typically regarded as a basic criterion to determine whether a given spacetime is regular or singular. However, the principle of general covariance does not privilege any family of observers over the others and, therefore, observers with arbitrary motions should be able to provide a complete physical description of the world. This suggests that in a regular spacetime, all physically acceptable observers should have complete paths. In this work we explore this idea by studying the motion of accelerated observers in spherically symmetric spacetimes and illustrate it by considering two geodesically complete black hole spacetimes recently described in the literature. We show that for bound and locally unbound accelerations, the paths of accelerated test particles are complete, providing further support to the regularity of such spacetimes.
Address [Olmo, Gonzalo J.; Sanchez-Puente, Antonio] Univ Valencia, Dept Fis Teor, CSIC, Ctr Mixto, E-46100 Valencia, Spain, Email: gonzalo.olmo@uv.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0264-9381 ISBN Medium
Area Expedition Conference
Notes WOS:000424042100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3473
Permanent link to this record