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Author Capozziello, S.; Harko, T.; Lobo, F.S.N.; Olmo, G.J.; Vignolo, S.
Title The Cauchy problem in hybrid metric-Palatini f(X)-gravity Type Journal Article
Year 2014 Publication International Journal of Geometric Methods in Modern Physics Abbreviated Journal Int. J. Geom. Methods Mod. Phys.
Volume 11 Issue 5 Pages 1450042 - 12pp
Keywords Cauchy problem; modified gravity; hybrid metric-Palatini gravity
Abstract The well-formulation and the well-posedness of the Cauchy problem are discussed for hybrid metric-Palatini gravity, a recently proposed modified gravitational theory consisting of adding to the Einstein-Hilbert Lagrangian an f(R)-term constructed a la Palatini. The theory can be recast as a scalar-tensor one predicting the existence of a light long-range scalar field that evades the local Solar System tests and is able to modify galactic and cosmological dynamics, leading to the late-time cosmic acceleration. In this work, adopting generalized harmonic coordinates, we show that the initial value problem can always be well-formulated and, furthermore, can be well-posed depending on the adopted matter sources.
Address [Capozziello, Salvatore] Univ Naples Federico II, Dipartimento Sci Fis, Naples, Italy, Email: capozzie@na.infn.it;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0219-8878 ISBN Medium
Area Expedition Conference
Notes WOS:000336527100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1813
Permanent link to this record
 
 
Author Sepehri, A.; Pincak, R.; Olmo, G.J.
Title M-theory, graphene-branes and superconducting wormholes Type Journal Article
Year 2017 Publication International Journal of Geometric Methods in Modern Physics Abbreviated Journal Int. J. Geom. Methods Mod. Phys.
Volume 14 Issue 11 Pages 1750167 - 32pp
Keywords M-theory; wormholes; graphene; superconductors
Abstract Exploiting an M-brane system whose structure and symmetries are inspired by those of graphene (what we call a graphene-brane), we propose here a similitude between two layers of graphene joined by a nanotube and wormholes scenarios in the brane world. By using the symmetries and mathematical properties of the M-brane system, we show here how to possibly increase its conductivity, to the point of making it as a superconductor. The questions of whether and under which condition this might point to the corresponding real graphene structures becoming superconducting are briefly outlined.
Address [Sepehri, Alireza] Shahid Bahonar Univ, Fac Phys, POB 76175, Kerman, Iran, Email: alireza.sepehri@uk.ac.ir;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0219-8878 ISBN Medium
Area Expedition Conference
Notes WOS:000413442500018 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3334
Permanent link to this record
 
 
Author Izadi, A.; Shacker, S.S.; Olmo, G.J.; Banerjee, R.
Title Observational effects of varying speed of light in quadratic gravity cosmological models Type Journal Article
Year 2018 Publication International Journal of Geometric Methods in Modern Physics Abbreviated Journal Int. J. Geom. Methods Mod. Phys.
Volume 15 Issue 5 Pages 1850084 - 16pp
Keywords Palatini formalism; modified gravity; causal structure constant; varying speed of light
Abstract We study different manifestations of the speed of light in theories of gravity where metric and connection are regarded as independent fields. We find that for a generic gravity theory in a frame with locally vanishing affine connection, the usual degeneracy between different manifestations of the speed of light is broken. In particular, the space-time causal structure constant (c(ST)) may become variable in that local frame. For theories of the form f(R, R-mu nu R-mu nu), this variation in c(ST) has an impact on the definition of the luminosity distance (and distance modulus), which can be used to confront the predictions of particular models against Supernovae type Ia (SN Ia) data. We carry out this test for a quadratic gravity model without cosmological constant assuming (i) a constant speed of light and (ii) a varying speed of light (VSL), and find that the latter scenario is favored by the data.
Address [Izadi, Azam] Khajeh Nasir Toosi Univ Technol, Dept Phys, Tehran, Iran, Email: aizadi@kntu.ac.ir;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0219-8878 ISBN Medium
Area Expedition Conference
Notes WOS:000429106400016 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3553
Permanent link to this record
 
 
Author Araujo Filho, A.A.; Reis, J.A.A.S.; Ghosh, S.
Title Quantum gases on a torus Type Journal Article
Year 2023 Publication International Journal of Geometric Methods in Modern Physics Abbreviated Journal Int. J. Geom. Methods Mod. Phys.
Volume 20 Issue 10 Pages 2350178 - 19pp
Keywords Thermodynamic properties; non-Cartesian geometries; grand canonical ensemble; noninteracting and interacting quantum gases; spinless; bosons and fermion particles
Abstract This paper is aimed at studying the thermodynamic properties of quantum gases confined to a torus. To do that, we consider noninteracting gases within the grand canonical ensemble formalism. In this context, fermions and bosons are taken into account and the calculations are properly provided in both analytical and numerical manners. In particular, the system turns out to be sensitive to the topological parameter under consideration: the winding number. Furthermore, we also derive a model in order to take into account interacting quantum gases. To corroborate our results, we implement such a method for two different scenarios: a ring and a torus.
Address [Araujo Filho, A. A.] Univ Fed Ceara UFC, Dept Fis, Campus Pici,CP 6030, BR-60455760 Fortaleza, CE, Brazil, Email: dilto@fisica.ufc.br;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0219-8878 ISBN Medium
Area Expedition Conference
Notes WOS:000988814200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5553
Permanent link to this record
 
 
Author Araujo Filho, A.A.
Title Thermodynamics of massless particles in curved spacetime Type Journal Article
Year 2023 Publication International Journal of Geometric Methods in Modern Physics Abbreviated Journal Int. J. Geom. Methods Mod. Phys.
Volume 12 Issue 13 Pages 2350226 - 40pp
Keywords Einstein-aether; thermodynamic properties; curved spacetime
Abstract This work is devoted to study the behavior of massless particles within the context of curved spacetime. In essence, we investigate the consequences of the scale factor C(?) of the Friedmann-Robertson-Walker metric in the Einstein-aether formalism to study photon-like particles. To do so, we consider the system within the canonical ensemble formalism in order to derive the following thermodynamic state quantities: spectral radiance, Helmholtz free energy, pressure, entropy, mean energy and the heat capacity. Moreover, the correction to the Stefan-Boltzmann law and the equation of states are also provided. Particularly, we separate our study within three distinct cases, i.e. s = 0, p = 0; s = 1, p = 1; s = 2, p = 1. In the first one, the results are derived numerically. Nevertheless, for the rest of the cases, all the calculations are accomplished analytically showing explicitly the dependence of the scale factor C(?) and the Riemann zeta function ?(s). Furthermore, our analyses are accomplished in general taking into account three different regimes of temperature of the universe, i.e. the inflationary era (T = 10(13)GeV), the electroweak epoch (T = 10(3)GeV) and the cosmic microwave background (T = 10(-13)GeV).
Address [Araujo Filho, A. A.] Univ Fed Cearra UFC, Dept Fis, Campus Pici,CP 6030, BR-60455760 Fortaleza, CE, Brazil, Email: dilto@fisica.ufc.br
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0219-8878 ISBN Medium
Area Expedition Conference
Notes WOS:001048378900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5613
Permanent link to this record
 
 
Author Chen, Y.H.; Yao, D.L.; Zheng, H.Q.
Title A Study of rho-omega Mixing in Resonance Chiral Theory Type Journal Article
Year 2018 Publication Communications in Theoretical Physics Abbreviated Journal Commun. Theor. Phys.
Volume 69 Issue 1 Pages 50-58
Keywords Chiral Lagrangians; vector mesons; 1/N-C expansion
Abstract The strong and electromagnetic corrections to rho-omega mixing are calculated using an SU(2) version of resonance chiral theory up to next-to-leading orders in 1/N-C expansion, respectively. Up to our accuracy, the effect of the momentum dependence of rho-omega mixing is incorporated due to the inclusion of loop contributions. We analyze the impact of rho-omega mixing on the pion vector form factor by performing numerical fit to the data extracted from e(+)e(-) -> pi(+)pi(-) and tau -> nu(tau)2 pi, while the decay width of omega -> pi(+)pi(-) is taken into account as a constraint. It is found that the momentum dependence is significant in a good description of the experimental data. In addition, based on the fitted values of the involved parameters, we analyze the decay width of omega -> pi(+)pi(-), which turns out to be highly dominated by the rho-omega mixing effect.
Address [Chen, Yun-Hua] Univ Sci & Technol Beijing, Sch Math & Phys, Beijing 100083, Peoples R China, Email: yhchen@ustb.edu.cn;
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 (up) 0253-6102 ISBN Medium
Area Expedition Conference
Notes WOS:000422832600010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3453
Permanent link to this record
 
 
Author Shi, P.P.; Baru, V.; Guo, F.K.; Hanhart, C.; Nefediev, A.
Title Production of the X(4014) as the Spin-2 Partner of X(3872) in e + e – Collisions Type Journal Article
Year 2024 Publication Chinese Physics Letters Abbreviated Journal Chin. Phys. Lett.
Volume 41 Issue 3 Pages 031301 - 7pp
Keywords
Abstract In 2021, the Belle collaboration reported the first observation of a new structure in the psi(2S)gamma final state produced in the two-photon fusion process. In the hadronic molecule picture, this new structure can be associated with the shallow isoscalar D*D* bound state and as such is an excellent candidate for the spin-2 partner of the X(3872) with the quantum numbers J(PC) = 2(++) conventionally named X-2. In this work we evaluate the electronic width of this new state and argue that its nature is sensitive to its total width, the experimental measurement currently available being unable to distinguish between different options. Our estimates demonstrate that the planned Super tau-Charm Facility offers a promising opportunity to search for and study this new state in the invariant mass distributions for the final states J/psi gamma and psi(2S)gamma.
Address [Shi, Pan-Pan; Guo, Feng-Kun] Chinese Acad Sci, CAS Key Lab Theoret Phys, Inst Theoret Phys, Beijing 100190, Peoples R China, Email: panpan@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 (up) 0256-307x ISBN Medium
Area Expedition Conference
Notes WOS:001189846900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6051
Permanent link to this record
 
 
Author Botella-Soler, V.; Glendinning, P.
Title Emergence of hierarchical networks and polysynchronous behaviour in simple adaptive systems Type Journal Article
Year 2012 Publication Europhysics Letters Abbreviated Journal EPL
Volume 97 Issue 5 Pages 50004 - 5pp
Keywords
Abstract We describe the dynamics of a simple adaptive network. The network architecture evolves to a number of disconnected components on which the dynamics is characterized by the possibility of differently synchronized nodes within the same network (polysynchronous states). These systems may have implications for the evolutionary emergence of polysynchrony and hierarchical networks in physical or biological systems modeled by adaptive networks.
Address [Botella-Soler, V.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Valencia, Spain, Email: vicente.botella@uv.es
Corporate Author Thesis
Publisher Epl Association, European Physical Society Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0295-5075 ISBN Medium
Area Expedition Conference
Notes WOS:000301952600004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 958
Permanent link to this record
 
 
Author Baker, M.J.; Bordes, J.; Hong-Mo, C.; Tsun, T.S.
Title On the corner elements of the CKM and PMNS matrices Type Journal Article
Year 2013 Publication Europhysics Letters Abbreviated Journal EPL
Volume 102 Issue 4 Pages 41001 - 6pp
Keywords
Abstract Recent experiments show that the top-right corner element (U-e3) of the PMNS matrix is small but nonzero, and suggest further via unitarity that it is smaller than the bottom-left corner element (U-tau 1). Here, it is shown that if to the assumption of a universal rank-one mass matrix, long favoured by phenomenologists, one adds that this matrix rotates with scale, then it follows that A) by inputting the mass ratios m(c)/m(t), m(s)/m(b), m(mu)/m(tau), and m(2)/m(3), i) the corner elements are small but nonzero, ii) V-ub < V-td, U-e3 < U-tau 1, iii) estimates result for the ratios V-ub/V-td and U-e3/U-tau 1, and B) by inputting further the experimental values of V-us, V-tb and U-e2, U-mu 3, iv) estimates result for the values of the corner elements themselves. All the inequalities and estimates obtained are consistent with present data within expectation for the approximations made.
Address [Baker, Michael J.; Bordes, Jose] Univ Valencia, Dept Fis Teor, E-46100 Burjassot, Valencia, Spain
Corporate Author Thesis
Publisher Epl Association, European Physical Society Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0295-5075 ISBN Medium
Area Expedition Conference
Notes WOS:000321118600014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1511
Permanent link to this record
 
 
Author Motohashi, H.; Starobinsky, A.A.
Title Constant-roll inflation: Confrontation with recent observational data Type Journal Article
Year 2017 Publication Europhysics Letters Abbreviated Journal EPL
Volume 117 Issue 3 Pages 39001 - 3pp
Keywords
Abstract The previously proposed class of phenomenological inflationary models in which the assumption of inflaton slow-roll is replaced by the more general, constant-roll condition is compared with the most recent cosmological observational data, mainly the Planck ones. Models in this two-parametric class which remain viable appear to be close to the slow-roll ones, and their inflaton potentials are close to (but still different from) that of the natural inflation model. The permitted regions for the two model parameters are presented.
Address [Motohashi, Hayato] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46980 Valencia, Spain
Corporate Author Thesis
Publisher Epl Association, European Physical Society Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0295-5075 ISBN Medium
Area Expedition Conference
Notes WOS:000401165300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3134
Permanent link to this record