|   | 
Details
   web
Records
Author Beltran Jimenez, J.; Heisenberg, L.; Olmo, G.J.; Rubiera-Garcia, D.
Title On gravitational waves in Born-Infeld inspired non-singular cosmologies Type Journal Article
Year 2017 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 10 Issue 10 Pages 029 - 23pp
Keywords alternatives to inflation; modified gravity; physics of the early universe; primordial gravitational waves (theory)
Abstract (down) We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisation of the gravitational waves evolution. We extend our analysis to more general Born-Infeld inspired theories where analogous solutions are found. As a general conclusion, we obtain that the bouncing solutions are generally more prone to instabilities, while the asymptotically Minkowski solutions can be rendered stable, making them appealing models for the early universe.
Address [Beltran Jimenez, Jose] Univ Toulon & Var, Aix Marseille Univ, CNRS, CPT, Marseille, France, Email: jose.beltran@uam.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:000413332400002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3337
Permanent link to this record
 

 
Author Gomez Dumm, D.; Noguera, S.; Scoccola, N.N.
Title eta-gamma and eta(')-gamma transition form factors in a nonlocal NJL model Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 95 Issue 5 Pages 054006 - 19pp
Keywords
Abstract (down) We study the eta and eta(') distribution amplitudes (DAs) in the context of a nonlocal SU(3)(L) circle times SUd(3)(R) chiral quark model. The corresponding Lagrangian allows us to reproduce the phenomenological values of pseudoscalar meson masses and decay constants, as well as the momentum dependence of the quark propagator arising from lattice calculations. It is found that the obtained DAs have two symmetric maxima, which arise from new contributions generated by the nonlocal character of the interactions. These DAs are then applied to the calculation of the eta-gamma and eta(')-gamma transition form factors. Implications of our results regarding higher twist corrections and/or contributions to the transition form factors originated by gluon-gluon components in the eta and eta(') mesons are discussed.
Address [Gomez Dumm, D.] Univ Nacl La Plata, Fac Ciencias Exactas, Dept Fis, IFLP,CONICET, CC 67, RA-1900 La Plata, Buenos Aires, Argentina
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:000396030600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3031
Permanent link to this record
 

 
Author de Rham, C.; Motohashi, H.
Title Caustics for spherical waves Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 95 Issue 6 Pages 064008 - 13pp
Keywords
Abstract (down) We study the development of caustics in shift-symmetric scalar field theories by focusing on simple waves with an SO(p)-symmetry in an arbitrary number of space dimensions. We show that the pure Galileon, the DBI-Galileon, and the extreme-relativistic Galileon naturally emerge as the unique set of caustic-free theories, highlighting a link between the caustic-free condition for simple SO(p)-waves and the existence of either a global Galilean symmetry or a global (extreme-) relativistic Galilean symmetry.
Address [de Rham, Claudia] Imperial Coll London, Blackett Lab, London SW7 2AZ, 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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000396031700006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3032
Permanent link to this record
 

 
Author Ballesteros, G.; Carmona, A.; Chala, M.
Title Exceptional composite dark matter Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 7 Pages 468 - 18pp
Keywords
Abstract (down) We study the darkmatter phenomenology of non-minimal composite Higgs models with SO(7) broken to the exceptional group G(2). In addition to the Higgs, three pseudo-Nambu-Goldstone bosons arise, one of which is electrically neutral. A parity symmetry is enough to ensure this resonance is stable. In fact, if the breaking of the Goldstone symmetry is driven by the fermion sector, this Z(2) symmetry is automatically unbroken in the electroweak phase. In this case, the relic density, as well as the expected indirect, direct and collider signals are then uniquely determined by the value of the compositeness scale, f. Current experimental bounds allow one to account for a large fraction of the dark matter of the Universe if the dark matter particle is part of an electroweak triplet. The totality of the relic abundance can be accommodated if instead this particle is a composite singlet. In both cases, the scale f and the dark matter mass are of the order of a few TeV.
Address [Ballesteros, Guillermo] Univ Paris Saclay, CNRS, Inst Phys Theor, CEA, F-91191 Gif Sur Yvette, France, Email: guillermo.ballesteros@cea.fr;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000405437500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3205
Permanent link to this record
 

 
Author Pagura, V.P.; Gomez Dumm, D.; Noguera, S.; Scoccola, N.N.
Title Magnetic catalysis and inverse magnetic catalysis in nonlocal chiral quark models Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 95 Issue 3 Pages 034013 - 7pp
Keywords
Abstract (down) We study the behavior of strongly interacting matter under an external constant magnetic field in the context of nonlocal chiral quark models within the mean field approximation. We find that at zero temperature the behavior of the quark condensates shows the expected magnetic catalysis effect, our predictions being in good quantitative agreement with lattice QCD results. On the other hand, in contrast to what happens in the standard local Nambu-Jona-Lasinio model, when the analysis is extended to the case of finite temperature, our results show that nonlocal models naturally lead to the inverse magnetic catalysis effect.
Address [Pagura, V. P.; Noguera, S.] Univ Valencia, CSIC, Ctr Mixto, Dept Fis Teor, E-46100 Burjassot, 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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000393853000002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2968
Permanent link to this record