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Author Harko, T.; Koivisto, T.S.; Lobo, F.S.N.; Olmo, G.J.; Rubiera-Garcia, D. url  doi
openurl 
  Title Coupling matter in modified Q gravity Type Journal Article
  Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 98 Issue 8 Pages (down) 084043 - 13pp  
  Keywords  
  Abstract We present a novel theory of gravity by considering an extension of symmetric teleparallel gravity. This is done by introducing, in the framework of the metric-affine formalism, a new class of theories where the nonmetricity Q is nonminimally coupled to the matter Lagrangian. More specifically, we consider a Lagrangian of the form L similar to f(1)(Q) + f(2)(Q)L-M, where f(1) and f(2) are generic functions of Q, and L-M is the matter Lagrangian. This nonminimal coupling entails the nonconservation of the energy-momentum tensor, and consequently the appearance of an extra force. The formulation of the gravity sector in terms of the Q instead of the curvature may result in subtle improvements of the theory. In the context of nonminimal matter couplings, we are therefore motivated to explore whether the new geometrical formulation in terms of the Q, when implemented also in the matter sector, would allow more universally consistent and viable realizations of the nonminimal coupling. Furthermore, we consider several cosmological applications by presenting the evolution equations and imposing specific functional forms of the functions f(1)(Q) and f(2)(Q), such as power-law and exponential dependencies of the nonminimal couplings. Cosmological solutions are considered in two general classes of models, and found to feature accelerating expansion at late times.  
  Address [Harko, Tiberiu] Babes Bolyai Univ, Dept Phys, Kogalniceanu St, Cluj Napoca 400084, Romania, Email: t.harko@ucl.ac.uk;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000448458600003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3789  
Permanent link to this record
 

 
Author Boudet, S.; Bombacigno, F.; Montani, G.; Rinaldi, M. url  doi
openurl 
  Title Superentropic black hole with Immirzi hair Type Journal Article
  Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 103 Issue 8 Pages (down) 084034 - 14pp  
  Keywords  
  Abstract In the context of f(R) generalizations to the Hoist action, endowed with a dynamical Immirzi field, we derive an analytic solution describing asymptotically anti-de Sitter black holes with hyperbolic horizon. These exhibit a scalar hair of the second kind, which ultimately depends on the Immirzi field radial behavior. In particular, we show how the Immirzi field modifies the usual entropy law associated to the black hole. We also verify that the Immirzi field boils down to a constant value in the asymptotic region, thus restoring the standard loop quantum gravity picture. We finally prove the violation of the reverse isoperimetric inequality, resulting in the superentropic nature of the black hole, and we discuss in detail the thermodynamic stability of the solution.  
  Address [Boudet, Simon; Rinaldi, Massimiliano] Univ Trento, Dipartimento Fis, Via Sommar 14, I-38123 Povo, TN, Italy, Email: simon.boudet@unitn.it;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000649081100011 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4833  
Permanent link to this record
 

 
Author Wang, D.; Mena, O. url  doi
openurl 
  Title Robust analysis of the growth of structure Type Journal Article
  Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 109 Issue 8 Pages (down) 083539 - 18pp  
  Keywords  
  Abstract Current cosmological tensions show that it is crucial to test the predictions from the canonical ACDM paradigm at different cosmic times. One very appealing test of structure formation in the Universe is the growth rate of structure in our universe f, usually parametrized via the growth index gamma, with f equivalent to Omega(m)(a)gamma and gamma similar or equal to 0.55 in the standard ACDM case. Recent studies have claimed a suppression of the growth of structure from a variety of cosmological observations, characterized by gamma > 0.55. By employing different self-consistent growth parametrizations schemes, we show here that gamma < 0.55, obtaining instead an enhanced growth of structure today. This preference reaches the 3 sigma significance using cosmic microwave background observations, supernova Ia and baryon acoustic oscillation measurements. The addition of cosmic microwave background lensing data relaxes such a preference to the 2 sigma level, since a larger lensing effect can always be compensated with a smaller structure growth, or, equivalently, with gamma > 0.55. We have also included the lensing amplitude AL as a free parameter in our data analysis, showing that the preference for AL > 1 still remains, except for some particular parametrizations when lensing observations are included. We also do not find any significant preference for an oscillatory dependence of AL, AL + Am sin l. To further reassess the effects of a nonstandard growth, we have computed by means of N-body simulations the dark matter density fields, the dark matter halo mass functions and the halo density profiles for different values of gamma. Future observations from the Square Kilometer Array, reducing by a factor of 3 the current errors on the gamma parameter, further confirm or refute with a strong statistical significance the deviation of the growth index from its standard value.  
  Address [Wang, Deng; Mena, Olga] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Paterna, Spain, Email: dengwang@ific.uv.es;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001224750700005 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 6130  
Permanent link to this record
 

 
Author Barenboim, G.; Kinney, W.H.; Morse, M.J.P. url  doi
openurl 
  Title Phantom Dirac-Born-Infeld dark energy Type Journal Article
  Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 98 Issue 8 Pages (down) 083531 - 11pp  
  Keywords  
  Abstract Motivated by the apparent discrepancy between cosmic microwave background measurements of the Hubble constant and measurements from Type-la supernovae, we construct a model for dark energy with equation of state w = p/rho < -1, violating the null energy condition. Naive canonical models of so-called “phantom” dark energy require a negative scalar kinetic term, resulting in a Hamiltonian unbounded from below and associated vacuum instability. We construct a scalar field model for dark energy with w < -1, which nonetheless has a Hamiltonian bounded from below in the comoving reference frame, i.e., in the rest frame of the fluid. We demonstrate that the solution is a cosmological attractor, and find that early-time cosmological boundary conditions consist of a “frozen” scalar field, which relaxes to the attractor solution once the dark energy component dominates the cosmological energy density. We consider the model in an arbitrary choice of gauge, and find that, unlike the case of comoving gauge, the fluid Hamiltonian is in fact unbounded from below in the reference frame of a highly boosted observer, corresponding to a nonlinear gradient instability. We discuss this in the context of general NEC-violating perfect fluids, for which this instability is a general property.  
  Address [Barenboim, Gabriela] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: Gabriela.Barenboim@uv.es;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000447934300002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3771  
Permanent link to this record
 

 
Author Esteban, I.; Mena, O.; Salvado, J. url  doi
openurl 
  Title Nonstandard neutrino cosmology dilutes the lensing anomaly Type Journal Article
  Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 106 Issue 8 Pages (down) 083516 - 9pp  
  Keywords  
  Abstract Despite the impressive success of the standard cosmological model, several anomalies defy its triumph. Among them is the so-called lensing anomaly: The Planck satellite observes stronger cosmic microwave background (CMB) gravitational lensing than expected. The role of neutrinos in this anomaly has been mostly overlooked, despite their key role in CMB lensing, because in the standard scenario they tend to increase the tension. Here, we show that this strongly depends on the assumed neutrino equation of state. We demonstrate that if neutrinos have yet undiscovered long-range interactions, the lensing pattern is significantly affected, rendering the lensing anomaly as a statistical fluctuation. Our results, thus, open up a window to link anomalous CMB lensing with present and future cosmological, astrophysical, and laboratory measurements of neutrino properties.  
  Address [Esteban, Ivan] Ohio State Univ, Ctr Cosmol & AstroParticle Phys CCAPP, Columbus, OH 43210 USA, Email: esteban.6@osu.edu;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000886611900003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5415  
Permanent link to this record
 

 
Author Barenboim, G.; Denton, P.B.; Oldengott, I.M. url  doi
openurl 
  Title Constraints on inflation with an extended neutrino sector Type Journal Article
  Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 99 Issue 8 Pages (down) 083515 - 9pp  
  Keywords  
  Abstract Constraints on inflationary models typically assume only the standard models of cosmology and particle physics. By extending the neutrino sector to include a new interaction with a light scalar mediator (m(phi) similar to MeV), it is possible to relax these constraints, in particular via opening up regions of the parameter space of the spectral index n(s). These new interactions can be probed at IceCube via interactions of astrophysical neutrinos with the cosmic neutrino background for nearly all of the relevant parameter space.  
  Address [Barenboim, Gabriela] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: Gabriela.Barenboim@uv.es;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000464746300005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3980  
Permanent link to this record
 

 
Author Yang, W.Q.; Mena, O.; Pan, S.; Di Valentino, E. url  doi
openurl 
  Title Dark sectors with dynamical coupling Type Journal Article
  Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 100 Issue 8 Pages (down) 083509 - 11pp  
  Keywords  
  Abstract Coupled dark matter-dark energy scenarios arc modeled via a dimensionless parameter xi, which controls the strength of their interaction. While this coupling is commonly assumed to be constant, there is no underlying physical law or symmetry that forbids a time-dependent xi parameter. The most general and complete interacting scenarios between the two dark sectors should therefore allow for such a possibility, and it is the main purpose of this study to constrain two possible and well-motivated coupled cosmologies by means of the most recent and accurate early- and late-time universe observations. We find that CMB data alone prefer xi(z) > 0 and therefore a smaller amount of dark matter, alleviating some crucial and well-known cosmological data tensions. An objective assessment of the Bayesian evidence for the coupled models explored here shows no particular preference for the presence of a dynamical dark sector coupling.  
  Address [Yang, Weiqiang] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: d11102004@163.com;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000489039100003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4166  
Permanent link to this record
 

 
Author Yang, W.Q.; Di Valentino, E.; Mena, O.; Pan, S.; Nunes, R.C. url  doi
openurl 
  Title All-inclusive interacting dark sector cosmologies Type Journal Article
  Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 101 Issue 8 Pages (down) 083509 - 15pp  
  Keywords  
  Abstract In this paper we explore possible extensions of interacting dark energy cosmologies, where dark energy and dark matter interact nongravitationally with one another. In particular, we focus on the neutrino sector, analyzing the effect of both neutrino masses and the effective number of neutrino species. We consider the Planck 2018 legacy release data combined with several other cosmological probes, finding no evidence for new physics in the dark radiation sector. The current neutrino constraints from cosmology should therefore be regarded as robust, as they are not strongly dependent on the dark sector physics, once all the available observations are combined. Namely, we find a total neutrino mass g, < 0.15 eV and a number of effective relativistic degrees of freedom N-eff = 3.03(-0.33)(+0.33), both at 95% C.L., which are close to those obtained within the ACDM cosmology, M-v < 0.12 eV and N-eff = (+0.36)(-0.35), for the same data combination.  
  Address [Yang, Weiqiang] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: d11102004@163.com;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000523633500002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4359  
Permanent link to this record
 

 
Author Di Valentino, E.; Gariazzo, S.; Giare, W.; Mena, O. url  doi
openurl 
  Title Impact of the damping tail on neutrino mass constraints Type Journal Article
  Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 108 Issue 8 Pages (down) 083509 - 11pp  
  Keywords  
  Abstract Model-independent mass limits assess the robustness of current cosmological measurements of the neutrino mass scale. Consistency between high-multipole and low-multiple cosmic microwave background observations measuring such scale further valuates the constraining power of present data. We derive here up-to-date limits on neutrino masses and abundances exploiting either the Data Release 4 of the Atacama Cosmology Telescope (ACT) or the South Pole Telescope polarization measurements from SPT-3G, envisaging different nonminimal background cosmologies and marginalizing over them. By combining these high-l observations with supernova Ia, baryon acoustic oscillations (BAO), redshift space distortions (RSD) and a prior on the reionization optical depth fromWMAP data, we find that the marginalized bounds are competitive with those from Planck analyses. We obtain Sigma m(nu) < 0.139 eV and N-eff = 2.82 +/- 0.25 in a dark energy quintessence scenario, both at 95% CL. These limits translate into Sigma m(nu) < 0.20 eV and N-eff = 2.79(-0.28)(+0.30) after marginalizing over a plethora of well-motivated fiducial models. Our findings reassess both the strength and the reliability of cosmological neutrino mass constraints.  
  Address [Di Valentino, Eleonora; Giare, William] Univ Sheffield, Sch Math & Stat, Hounsfield Rd, Sheffield S3 7RH, S Yorkshire, England, Email: e.divalentino@sheffield.ac.uk;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001157784100002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5935  
Permanent link to this record
 

 
Author Di Valentino, E.; Gariazzo, S.; Mena, O. url  doi
openurl 
  Title Most constraining cosmological neutrino mass bounds Type Journal Article
  Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 104 Issue 8 Pages (down) 083504 - 7pp  
  Keywords  
  Abstract We present here up-to-date neutrino mass limits exploiting the most recent cosmological data sets. By making use of the cosmic microwave background temperature fluctuation and polarization measurements, supernovae Ia luminosity distances, baryon acoustic oscillation observations and determinations of the growth rate parameter, we are able to set the most constraining bound to date, Sigma m(v) < 0.09 eV at 95% C.L. This very tight limit is obtained without the assumption of any prior on the value of the Hubble constant and highly compromises the viability of the inverted mass ordering as the underlying neutrino mass pattern in nature. The results obtained here further strengthen the case for very large multitracer spectroscopic surveys as unique laboratories for cosmological relics, such as neutrinos: that would be the case of the Dark Energy Spectroscopic Instrument survey and of the Euclid mission.  
  Address [Di Valentino, Eleonora] Univ Durham, Inst Particle Phys Phenomenol, Dept Phys, Durham DH1 3LE, England, Email: eleonora.di-valentino@durham.ac.uk;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000704632300010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4996  
Permanent link to this record
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