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Author Barrientos, E.; Lobo, F.S.N.; Mendoza, S.; Olmo, G.J.; Rubiera-Garcia, D.
Title Metric-affine f(R,T) theories of gravity and their applications Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 97 Issue 10 Pages (down) 104041 - 10pp
Keywords
Abstract We study f (R, T) theories of gravity, where T is the trace of the energy-momentum tensor T-mu v, with independent metric and affine connection (metric-affine theories). We find that the resulting field equations share a close resemblance with their metric-affine f(R) relatives once an effective energy-momentum tensor is introduced. As a result, the metric field equations are second-order and no new propagating degrees of freedom arise as compared to GR, which contrasts with the metric formulation of these theories, where a dynamical scalar degree of freedom is present. Analogously to its metric counterpart, the field equations impose the nonconservation of the energy-momentum tensor, which implies nongeodesic motion arid consequently leads to the appearance of an extra force. The weak field limit leads to a modified Poisson equation formally identical to that found in Eddington-inspired Born-Infeld gravity. Furthermore, the coupling of these gravity theories to perfect fluids, electromagnetic, and scalar fields, and their potential applications arc discussed.
Address [Barrientos, E.; Mendoza, S.] Univ Nacl Autonoma Mexico, Inst Astron, AP 70-264, Ciudad De Mexico 04510, Mexico, Email: ebarrientos@astro.unam.mx;
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:000433036500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3585
Permanent link to this record
 
 
Author Casals, M.; Fabbri, A.; Martinez, C.; Zanelli, J.
Title Quantum-corrected rotating black holes and naked singularities in (2+1) dimensions Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue 10 Pages (down) 104023 - 39pp
Keywords
Abstract We analytically investigate the perturbative effects of a quantum conformally coupled scalar field on rotating (2 + 1)-dimensional black holes and naked singularities. In both cases we obtain the quantum-back-reacted metric analytically. In the black hole case, we explore the quantum corrections on different regions of relevance for a rotating black hole geometry. We find that the quantum effects lead to a growth of both the event horizon and the ergosphere, as well as to a reduction of the angular velocity compared to their corresponding unperturbed values. Quantum corrections also give rise to the formation of a curvature singularity at the Cauchy horizon and show no evidence of the appearance of a superradiant instability. In the naked singularity case, quantum effects lead to the formation of a horizon that hides the conical defect, thus turning it into a black hole. The fact that these effects occur not only for static but also for spinning geometries makes a strong case for the role of quantum mechanics as a cosmic censor in Nature.
Address [Casals, Marc] CBPF, BR-22290180 Rio De Janeiro, Brazil, Email: mcasals@cbpf.br;
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:000509560700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4263
Permanent link to this record
 
 
Author Lobo, F.S.N.; Olmo, G.J.; Orazi, E.; Rubiera-Garcia, D.; Rustam, A.
Title Structure and stability of traversable thin-shell wormholes in Palatini f(R) gravity Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 102 Issue 10 Pages (down) 104012 - 11pp
Keywords
Abstract We study the structure and stability of traversable wormholes built as (spherically symmetric) thin shells in the context of Palatini f(R) gravity. Using a suitable junction formalism for these theories we find that the effective number of degrees of freedom on the shell is reduced to a single one, which fixes the equation of state to be that of massless stress-energy fields, contrary to the general relativistic and metric f(R) cases. Another major difference is that the surface energy density threading the thin shell, needed in order to sustain the wormhole, can take any sign and may even vanish, depending on the desired features of the corresponding solutions. We illustrate our results by constructing thin-shell wormholes by surgically grafting Schwarzschild space-times and show that these configurations are always linearly unstable. However, surgically joined Reissner-Nordstrom space-times allow for linearly stable, traversable thin-shell wormholes supported by a positive energy density provided that the (squared) mass-to-charge ratio, given by y = Q(2)/M-2, satisfies the constraint 1 < y < 9/8 (corresponding to overcharged Reissner-Nordstrom configurations having a photon sphere) and lies in a region bounded by specific curves defined in terms of the (dimensionless) radius of the shell x(0) = R/M.
Address [Lobo, Francisco S. N.] Univ Lisbon, Fac Ciencias, Inst Astrofis & Ciencias Espaco, Edificio C8,Campo Grande, P-1749016 Lisbon, Portugal, Email: fslobo@fc.ul.pt;
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:000587286200006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4596
Permanent link to this record
 
 
Author Albaladejo, M.; Bibrzycki, L.; Dawid, S.M.; Fernandez-Ramirez, C.; Gonzalez-Solis, S.; Hiller Blin, A.N.; Jackura, A.W.; Mathieu, V.; Mikhasenko, M.; Make, V.I.; Passemar, E.; Pilloni, A.; Rodas, A.; Silva-Castro, J.A.; Smith, W.A.; Szczepaniak, A.P.; Winney, D.
Title Novel approaches in hadron spectroscopy Type Journal Article
Year 2022 Publication Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.
Volume 127 Issue Pages (down) 103981 - 75pp
Keywords Hadron spectroscopy; Exotic hadrons; Three-body scattering; Resonance production
Abstract The last two decades have witnessed the discovery of a myriad of new and unexpected hadrons. The future holds more surprises for us, thanks to new-generation experiments. Understanding the signals and determining the properties of the states requires a parallel theoretical effort. To make full use of available and forthcoming data, a careful amplitude modeling is required, together with a sound treatment of the statistical uncertainties, and a systematic survey of the model dependencies. We review the contributions made by the Joint Physics Analysis Center to the field of hadron spectroscopy.
Address [Albaladejo, Miguel; Blin, Astrid N. Hiller; Jackura, Andrew W.; Mokeev, Victor, I; Passemar, Emilie; Rodas, Arkaitz; Szczepaniak, Adam P.] Thomas Jefferson Natl Accelerator Facil, Theory Ctr & Phys Div, Newport News, VA 23606 USA, Email: alessandro.pilloni@unime.it
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-6410 ISBN Medium
Area Expedition Conference
Notes WOS:000883770300003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5422
Permanent link to this record
 
 
Author Addazi, A. et al; Martinez-Mirave, P.; Mitsou, V.A.; Palomares-Ruiz, S.; Tortola, M.; Zornoza, J.D.
Title Quantum gravity phenomenology at the dawn of the multi-messenger era-A review Type Journal Article
Year 2022 Publication Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.
Volume 125 Issue Pages (down) 103948 - 119pp
Keywords Lorentz invariance violation and deformation; Gamma-ray astronomy; Cosmic neutrinos; Ultra-high-energy cosmic rays; Gravitational waves
Abstract The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review, prepared within the COST Action CA18108 “Quantum gravity phenomenology in the multi-messenger approach”, is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers.
Address [Addazi, A.] Sichuan Univ, Coll Phys, Ctr Theoret Phys, Chengdu 610065, Peoples R China, Email: jcarmona@unizar.es
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-6410 ISBN Medium
Area Expedition Conference
Notes WOS:000830343400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5312
Permanent link to this record
 
 
Author Davesne, D.; Pastore, A.; Navarro, J.
Title Linear response theory with finite-range interactions Type Journal Article
Year 2021 Publication Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.
Volume 120 Issue Pages (down) 103870 - 55pp
Keywords Linear response theory; Finite-range interactions; Gogny and Nakada interactions; Finite size instabilities; Continued fraction approximation; Multipolar expansion
Abstract This review focuses on the calculation of infinite nuclear matter response functions using phenomenological finite-range interactions, equipped or not with tensor terms. These include Gogny and Nakada families, which are commonly used in the literature. Because of the finite-range, the main technical difficulty stems from the exchange terms of the particle-hole interaction. We first present results based on the so-called Landau and Landau-like approximations of the particle-hole interaction. Then, we review two methods which in principle provide numerically exact response functions. The first one is based on a multipolar expansion of both the particle-hole interaction and the particle-hole propagator and the second one consists in a continued fraction expansion of the response function. The numerical precision can be pushed to any degree of accuracy, but it is actually shown that two or three terms suffice to get converged results. Finally, we apply the formalism to the determination of possible finite-size instabilities induced by a finite-range interaction.
Address [Davesne, D.] Univ Lyon, F-69003 Lyon, France, Email: alessandro.pastore@york.ac.uk
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-6410 ISBN Medium
Area Expedition Conference
Notes WOS:000674530100008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4910
Permanent link to this record
 
 
Author Pich, A.
Title Precision physics with inclusive QCD processes Type Journal Article
Year 2021 Publication Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.
Volume 117 Issue Pages (down) 103846 - 41pp
Keywords QCD; Standard Model; Precision physics
Abstract The inclusive production of hadrons through electroweak currents can be rigorously analysed with short-distance theoretical tools. The associated observables are insensitive to the involved infrared behaviour of the strong interaction, allowing for very precise tests of Quantum Chromodynamics. The theoretical predictions for sigma(e(+)e(-) -> hadrons) and the hadronic decay widths of the tau lepton and the Z, W and Higgs bosons have reached an impressive accuracy of O(alpha(4)(s)). Precise experimental measurements of the Z and tau hadronic widths have made possible the accurate determination of the strong coupling at two very different energy scales, providing a highly significant experimental verification of asymptotic freedom. A detailed discussion of the theoretical description of these processes and their current phenomenological status is presented. The most precise determinations of alpha(s) from other sources are also briefly reviewed and compared with the fully-inclusive results.
Address [Pich, Antonio] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Parc Cient,Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: antonio.pich@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-6410 ISBN Medium
Area Expedition Conference
Notes WOS:000671808200002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4916
Permanent link to this record
 
 
Author Carrasco-Ribelles, L.A.; Pardo-Mas, J.R.; Tortajada, S.; Saez, C.; Valdivieso, B.; Garcia-Gomez, J.M.
Title Predicting morbidity by local similarities in multi-scale patient trajectories Type Journal Article
Year 2021 Publication Journal of Biomedical Informatics Abbreviated Journal J. Biomed. Inform.
Volume 120 Issue Pages (down) 103837 - 9pp
Keywords Patient trajectory; Risk prediction; Local alignment; Dynamic programming; Diabetes; Cardiovascular disease
Abstract Patient Trajectories (PTs) are a method of representing the temporal evolution of patients. They can include information from different sources and be used in socio-medical or clinical domains. PTs have generally been used to generate and study the most common trajectories in, for instance, the development of a disease. On the other hand, healthcare predictive models generally rely on static snapshots of patient information. Only a few works about prediction in healthcare have been found that use PTs, and therefore benefit from their temporal dimension. All of them, however, have used PTs created from single-source information. Therefore, the use of longitudinal multi-scale data to build PTs and use them to obtain predictions about health conditions is yet to be explored. Our hypothesis is that local similarities on small chunks of PTs can identify similar patients concerning their future morbidities. The objectives of this work are (1) to develop a methodology to identify local similarities between PTs before the occurrence of morbidities to predict these on new query individuals; and (2) to validate this methodology on risk prediction of cardiovascular diseases (CVD) occurrence in patients with diabetes. We have proposed a novel formal definition of PTs based on sequences of longitudinal multi-scale data. Moreover, a dynamic programming methodology to identify local alignments on PTs for predicting future morbidities is proposed. Both the proposed methodology for PT definition and the alignment algorithm are generic to be applied on any clinical domain. We validated this solution for predicting CVD in patients with diabetes and we achieved a precision of 0.33, a recall of 0.72 and a specificity of 0.38. Therefore, the proposed solution in the diabetes use case can result of utmost utility to secondary screening.
Address [Carrasco-Ribelles, Lucia A.; Pardo-Mas, Jose Ramon; Saez, Carlos; Garcia-Gomez, Juan M.] Univ Politecn Valencia, Biomed Data Sci Lab BDSLAB, Inst Tecnol Informat & Comunicac ITACA, Camino Vera S-N, Valencia 46022, Spain, Email: lucarri@etsii.upv.es;
Corporate Author Thesis
Publisher Academic Press Inc Elsevier Science Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1532-0464 ISBN Medium
Area Expedition Conference
Notes WOS:000683527500003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4934
Permanent link to this record
 
 
Author Giare, W.; Mena, O.; Di Valentino, E.
Title Lensing impact on cosmic relics and tensions Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 108 Issue 10 Pages (down) 103539 - 9pp
Keywords
Abstract Cosmological bounds on neutrinos and additional hypothetical light thermal relics, such as QCD axions, are currently among the most restrictive ones. These limits mainly rely on cosmic microwave background temperature anisotropies. Nonetheless, one of the largest cosmological signatures of thermal relics is that on gravitational lensing, due to their free-streaming behavior before their nonrelativistic period. We investigate late-time only hot-relic mass constraints, primarily based on recently released lensing data from the Atacama Cosmology Telescope, both alone and in combination with lensing data from the Planck satellite. Additionally, we consider other local probes, such as baryon acoustic oscillations measurements, shear-shear, galaxy-galaxy, and galaxy-shear correlation functions from the dark energy survey, and distance moduli measurements from Type-Ia Supernovae. The tightest bounds we find are Sigma m(v) < 0.43 eV and m(a) < 1.1 eV, both at 95% CL Interestingly, these limits are still much stronger than those found on e.g., laboratory neutrino mass searches, reassessing the robustness of the extraction of thermal relic properties via cosmological observations. In addition, when considering lensing-only data, the significance of the Hubble constant tension is considerably reduced, while the clustering parameter sigma 8 controversy is completely absent.
Address [Giare, William] Univ Sheffield, Sch Math & Stat, Consortium Fundamental Phys, Hounsfield Rd, Sheffield S3 7RH, England, Email: w.giare@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:001121804800014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5862
Permanent link to this record
 
 
Author Servant, G.; Simakachorn, P.
Title Ultrahigh frequency primordial gravitational waves beyond the kHz: The case of cosmic strings Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue 10 Pages (down) 103538 - 24pp
Keywords
Abstract We investigate gravitational -wave backgrounds (GWBs) of primordial origin that would manifest only at ultrahigh frequencies, from kilohertz to 100 gigahertz, and leave no signal at LIGO, the Einstein Telescope, the Cosmic Explorer, LISA, or pulsar -timing arrays. We focus on GWBs produced by cosmic strings and make predictions for the GW spectra scanning over high-energy scale (beyond 10 10 GeV) particle physics parameters. Signals from local string networks can easily be as large as the big bang nucleosynthesis/ cosmic microwave background bounds, with a characteristic strain as high as 10 – 26 in the 10 kHz band, offering prospects to probe grand unification physics in the 10 14 -10 17 GeV energy range. In comparison, GWB from axionic strings is suppressed (with maximal characteristic strain similar to 10 – 31 ) due to the early matter era induced by the associated heavy axions. We estimate the needed reach of hypothetical futuristic GW detectors to probe such GWB and, therefore, the corresponding high-energy physics processes. Beyond the information of the symmetry -breaking scale, the high -frequency spectrum encodes the microscopic structure of the strings through the position of the UV cutoffs associated with cusps and kinks, as well as potential information about friction forces on the string. The IR slope, on the other hand, reflects the physics responsible for the decay of the string network. We discuss possible strategies for reconstructing the scalar potential, particularly the scalar self -coupling, from the measurement of the UV cutoff of the GW spectrum.
Address [Servant, Geraldine] Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany, Email: peera.simakachorn@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:001238459100006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6150
Permanent link to this record