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Author Afonso, V.I.; Olmo, G.J.; Orazi, E.; Rubiera-Garcia, D.
Title Correspondence between modified gravity and general relativity with scalar fields Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue 4 Pages 044040 - 15pp
Keywords
Abstract (down) We describe a novel procedure to map the field equations of nonlinear Ricci-based metric-affine theories of gravity, coupled to scalar matter described by a given Lagrangian, into the field equations of general relativity coupled to a different scalar field Lagrangian. Our analysis considers examples with a single and N real scalar fields, described either by canonical Lagrangians or by generalized functions of the kinetic and potential terms. In particular, we consider several explicit examples involving foRthorn theories and the Eddington-inspired Born-Infeld gravity model, coupled to different scalar field Lagrangians. We show how the nonlinearities of the gravitational sector of these theories can be traded to nonlinearities in the matter fields and how the procedure allows to find new solutions on both sides of the correspondence. The potential of this procedure for applications of scalar field models in astrophysical and cosmological scenarios is highlighted.
Address [Afonso, Victor, I] Univ Fed Campina Grande, Unidade Acad Fis, BR-58429900 Campina Grande, Paraiba, Brazil, Email: viafonso@df.ufcg.cdu.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:000459210600012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3914
Permanent link to this record
 
 
Author Volpe, C.; Vaananen, D.; Espinoza, C.
Title Extended evolution equations for neutrino propagation in astrophysical and cosmological environments Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue 11 Pages 113010 - 17pp
Keywords
Abstract (down) We derive the evolution equations for a system of neutrinos interacting among themselves and with a matter background, based upon the Bogoliubov-Born-Green-Kirkwood-Yvon hierarchy. This theoretical framework gives an (unclosed) set of first-order coupled integro-differential equations governing the evolution of the reduced density matrices. By employing the hierarchy, we first rederive the mean-field evolution equations for the neutrino one-body density matrix associated with a system of neutrinos and antineutrinos interacting with matter and with an anisotropic neutrino background. Then, we derive extended evolution equations to determine neutrino flavor conversion beyond the commonly used mean-field approximation. To this aim we include neutrino-antineutrino pairing correlations to the two-body density matrix. The inclusion of these new contributions leads to an extended evolution equation for the normal neutrino density and to an equation for the abnormal one involving the pairing mean field. We discuss the possible impact of neutrino-antineutrino correlations on neutrino flavor conversion in the astrophysical and cosmological environments, and possibly upon the supernova dynamics. Our results can be easily generalized to an arbitrary number of neutrino families.
Address Univ Paris 07, AstroParticule & Cosmol APC, CNRS, F-75205 Paris 13, France, Email: volpe@apc.univ-paris7.fr;
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000320951500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1478
Permanent link to this record
 
 
Author Bernabeu, J.; Espriu, D.; Puigdomenech, D.
Title Gravitational waves in the presence of a cosmological constant Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 6 Pages 063523 - 13pp
Keywords
Abstract (down) We derive the effects of a nonzero cosmological constant Lambda on gravitational wave propagation in the linearized approximation of general relativity. In this approximation, we consider the situation where the metric can be written as g(mu nu) = eta(mu nu) + h(mu nu)(Lambda) + h(mu nu)(W), h(mu nu)(Lambda,W) << 1, where h(mu nu)(Lambda) is the background perturbation and h(mu nu)(W) is a modification interpretable as a gravitational wave. For Lambda not equal 0, this linearization of Einstein equations is self-consistent only in certain coordinate systems. The cosmological Friedmann-Robertson-Walker coordinates do not belong to this class and the derived linearized solutions have to be reinterpreted in a coordinate system that is homogeneous and isotropic to make contact with observations. Plane waves in the linear theory acquire modifications of order root Lambda, both in the amplitude and the phase, when considered in Friedmann-Robertson-Walker coordinates. In the linearization process for h(mu nu), we have also included terms of order O(Lambda h(mu nu)). For the background perturbation h(mu nu)(Lambda), the difference is very small, but when the term h(mu nu)(W)Lambda is retained the equations of motion can be interpreted as describing massive spin-2 particles. However, the extra degrees of freedom can be approximately gauged away, coupling to matter sources with a strength proportional to the cosmological constant itself. Finally, we discuss the viability of detecting the modifications caused by the cosmological constant on the amplitude and phase of gravitational waves. In some cases, the distortion with respect to gravitational waves propagating in Minkowski space-time is considerable. The effect of Lambda could have a detectable impact on pulsar timing arrays.
Address [Bernabeu, J] Univ Valencia, Dept Fis Teor IFIC, CSIC, E-46100 Valencia, Spain
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000295223100005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 766
Permanent link to this record
 
 
Author Caputo, A.; Sberna, L.; Frias, M.; Blas, D.; Pani, P.; Shao, L.J.; Yan, W.M.
Title Constraints on millicharged dark matter and axionlike particles from timing of radio waves Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 6 Pages 063515 - 7pp
Keywords
Abstract (down) We derive constraints on millicharged dark matter and axionlike particles using pulsar timing and fast radio burst observations. For dark matter particles of charge epsilon e, the constraint from time of arrival (TOA) of waves is epsilon/m(milli) less than or similar to 10(-8) eV(-1), for masses m(milli) greater than or similar to 10(-6) eV. For axionlike particles, the polarization of the signals from pulsars yields a bound in the axial coupling g/ m(a) less than or similar to 10(-13) Gev(-1)/(10(-22) eV),for m(a) less than or similar to 10(-19) eV. Both bounds scale as (rho/rho(dm))(1/2 )for fractions of the total dark matter energy density rho(dm). We make a precise study of these bounds using TOA from several pulsars, FRB 121102, and polarization measurements of PSR J0437 – 4715. Our results rule out a new region of the parameter space for these dark matter models.
Address [Caputo, Andrea] Univ Valencia, Inst Fis Corpuscular, Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: lsberna@perimeterinstitute.ca
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:000486646600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4147
Permanent link to this record
 
 
Author Albertus, C.; Aoki, Y.; Boyle, P.A.; Christ, N.H.; Dumitrescu, T.T.; Flynn, J.M.; Ishikawa, T.; Izubuchi, T.; Loktik, O.; Sachrajda, C.T.; Soni, A.; Van de Water, R.S.; Wennekers, J.; Witzel, O.
Title Neutral B-meson mixing from unquenched lattice QCD with domain-wall light quarks and static b quarks Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 82 Issue 1 Pages 014505 - 29pp
Keywords
Abstract (down) We demonstrate a method for calculating the neutral B-meson decay constants and mixing matrix elements in unquenched lattice QCD with domain-wall light quarks and static b-quarks. Our computation is performed on the "2 + 1'' flavor gauge configurations generated by the RBC and UKQCD Collaborations with a lattice spacing of a approximate to 0.11 fm (a(-1) = 1.729 GeV) and a lattice spatial volume of approximately (1.8 fm)(3). We simulate at three different light sea quark masses with pion masses down to approximately 430 MeV, and extrapolate to the physical quark masses using a phenomenologically-motivated fit function based on next-to-leading order heavy-light meson SU(2) chiral perturbation theory. For the b-quarks, we use an improved formulation of the Eichten-Hill action with static link-smearing to increase the signal-to-noise ratio. We also improve the heavy-light axial current used to compute the B-meson decay constant to O(alpha(s)pa) using one-loop lattice perturbation theory. We present initial results for the SU(3)-breaking ratios f(Bs)/f(Bd) and xi = f(Bs)root B-Bs/f(Bd)root B-Bd, thereby demonstrating the viability of the method. For the ratio of decay constants, we find f(Bs)/f(Bd) = 1.15(12) and for the ratio of mixing matrix elements, we find xi = 1.13(12), where in both cases the errors reflect the combined statistical and systematic uncertainties, including an estimate of the size of neglected O(1/m(b)) effects.
Address [Albertus, C.; Flynn, J. M.; Sachrajda, C. T.] Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000280124300003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 405
Permanent link to this record
 
 
Author Tang, C.; Gao, F.; Liu, Y.X.
Title Practical scheme from QCD to phenomena via Dyson-Schwinger equations Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 5 Pages 056001 - 16pp
Keywords
Abstract (down) We deliver a scheme to compute the quark propagator and the quark-gluon interaction vertex through the coupled Dyson-Schwinger equations (DSEs) of QCD. We take the three-gluon vertex into account in our calculations, and implement the gluon propagator and the running coupling function fitted by the solutions of their respective DSEs. We obtain the momentum and current mass dependence of the quark propagator and the quark-gluon vertex, and the chiral quark condensate that agrees with previous results excellently. We also compute the quark-photon vertex within this scheme and give the anomalous chromo- and electromagnetic moment of the quark. The obtained results are excellently consistent with previous ones. These applications manifest that the scheme is realistic and then practical for explaining the QCD-related phenomena.
Address [Tang, Can; Liu, Yu-xin] Peking Univ, Dept Phys, Beijing 100871, Peoples R China, Email: yxliu@pku.edu.cn
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:000483583000008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4128
Permanent link to this record
 
 
Author Celis, A.; Fuentes-Martin, J.; Jung, M.; Serodio, H.
Title Family nonuniversal Z ' models with protected flavor-changing interactions Type Journal Article
Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 92 Issue 1 Pages 015007 - 17pp
Keywords
Abstract (down) We define a new class of Z' models with neutral flavor-changing interactions at tree level in the down-quark sector. They are related in an exact way to elements of the quark mixing matrix due to an underlying flavored U(1)' gauge symmetry, rendering these models particularly predictive. The same symmetry implies lepton-flavor nonuniversal couplings, fully determined by the gauge structure of the model. Our models allow us to address presently observed deviations from the standard model and specific correlations among the new physics contributions to the Wilson coefficients C-9, 10((')l) can be tested in b -> sl(+)l(-) transitions. We furthermore predict lepton-universality violations in Z' decays, testable at the LHC.
Address [Celis, Alejandro] Univ Munich, Fak Phys, Arnold Sommerfeld Ctr Theoret Phys, D-80333 Munich, Germany, Email: alejandro.celis@physik.uni-muenchen.de;
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000357859300004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2341
Permanent link to this record
 
 
Author Bazeia, D.; Marques, M.A.; Olmo, G.J.
Title Small and hollow magnetic monopoles Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 2 Pages 025017 - 8pp
Keywords
Abstract (down) We deal with the presence of magnetic monopoles in a non-Abelian model that generalizes the standard 't Hooft-Polyakov model in three spatial dimensions. We investigate the energy density of the static and spherically symmetric solutions to find first order differential equations that solve the equations of motion. The system is further studied and two distinct classes of solutions are obtained, one that can also be described by analytical solutions and is called a small monopole, since it is significantly smaller than the standard 't Hooft-Polyakov monopole. The other type of structure is the hollow monopole, since the energy density is endowed with a hole at its core. The hollow monopole can be smaller or larger than the standard monopole, depending on the value of the parameter that controls the magnetic permeability of the model.
Address [Bazeia, D.; Marques, M. A.; Olmo, Gonzalo J.] Univ Fed Paraiba, Dept Fis, BR-58051970 Joao Pessoa, Paraiba, Brazil
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:000439545000007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3672
Permanent link to this record
 
 
Author Nieves, J.; Pich, A.; Ruiz Arriola, E.
Title Large-N(C) properties of the rho and f(0)(600) mesons from unitary resonance chiral dynamics Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 9 Pages 096002 - 20pp
Keywords
Abstract (down) We construct pi pi amplitudes that fulfill exact elastic unitarity, account for one-loop chiral perturbation theory contributions and include all 1/N(C) leading terms, with the only limitation of considering just the lowest-lying nonet of exchanged resonances. Within such a scheme, the N(C) dependence of sigma and rho masses and widths is discussed. Robust conclusions are drawn in the case of the rho resonance, confirming that it is a stable meson in the limit of a large number of QCD colors, N(C). Less definitive conclusions are reached in the scalar-isoscalar sector. With the present quality of data, we cannot firmly conclude whether or not the N(C) = 3 f(0)(600) resonance completely disappears at large N(C) or if it has a subdominant component in its structure, which would become dominant for a number of quark colors sufficiently large.
Address [Nieves, J] Ctr Mixto Univ Valencia, Inst Fis Corpuscular, CSIC, IFIC, Valencia 46071, Spain
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000296890300012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 799
Permanent link to this record
 
 
Author Arbelaez, C.; Fonseca, R.M.; Romao, J.C.; Hirsch, M.
Title Supersymmetric SO(10)-inspired GUTs with sliding scales Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue 7 Pages 075010 - 19pp
Keywords
Abstract (down) We construct lists of supersymmetric models with extended gauge groups at intermediate steps, all of which are inspired by SO(10) unification. We consider three different kinds of setups: (i) the model has exactly one additional intermediate scale with a left-right (LR) symmetric group; (ii) SO(10) is broken to the LR group via an intermediate Pati-Salam scale; and (iii) the LR group is broken into SU(3)(c) X SU(2)(L) X U(1)(R) X U(1)(B-L), before breaking to the standard model (SM) group. We use sets of conditions, which we call the “sliding mechanism,” which yield unification with the extended gauge group(s) allowed at arbitrary intermediate energy scales. All models thus can have new gauge bosons within the reach of the LHC, in principle. We apply additional conditions, such as perturbative unification, renormalizability and anomaly cancellation and find that, despite these requirements, for the ansatz (i) with only one additional scale still around 50 different variants exist that can have a LR symmetry below 10 TeV. For the more complicated schemes (ii) and (iii) literally thousands of possible variants exist, and for scheme (ii) we have also found variants with very low Pati-Salam scales. We also discuss possible experimental tests of the models from measurements of supersymmetry masses. Assuming mSugra boundary conditions we calculate certain combinations of soft terms, called “invariants,” for the different classes of models. Values for all the invariants can be classified into a small number of sets, which contain information about the class of models and, in principle, the scale of beyond-minimal supersymmetric extension of the Standard Model physics, even in case the extended gauge group is broken at an energy beyond the reach of the LHC.
Address Univ Tecn Lisboa, Dept Fis, P-1049001 Lisbon, Portugal, Email: Carolina.Arbelaez@ist.utl.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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000317586900007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1401
Permanent link to this record