Records |
Author |
Lessa, L.A.; Maluf, R.V.; Silva, J.E.G.; Almeida, C.A.S. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Braneworlds in warped Einsteinian cubic gravity |
Type |
Journal Article |
Year |
2024 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
05 |
Issue |
5 |
Pages |
123 - 25pp |
Keywords |
Gauss-Bonnet-Lovelock-Horndeski-Palatini etc gravity theories; gravity; modified gravity |
Abstract |
Einstenian cubic gravity (ECG) is a modified theory of gravity constructed with cubic contractions of the curvature tensor. This theory has the remarkable feature of having the same two propagating degrees of freedom of Einstein gravity (EG), at the perturbative level on maximally symmetric spacetimes. The additional unstable modes steaming from the higher order derivative dynamics are suppressed provided that we consider the ECG as an effective field theory wherein the cubic terms are seen as perturbative corrections of the Einstein -Hilbert term. Extensions of ECG have been proposed in cosmology and compact objects in order to probe if this property holds in more general configurations. In this work, we construct a modified ECG gravity in a five dimensional warped braneworld scenario. By assuming a specific combination of the cubic parameters, we obtained modified gravity equations of motion with terms up to second -order. For a thin 3-brane, the cubic -gravity corrections yield an effective positive bulk cosmological constant. Thus, in order to keep the 5D bulk warped compact, an upper bound of the cubic parameter with respect to the bulk curvature was imposed. For a thick brane, the cubic -gravity terms modify the scalar field potential and its corresponding vacuum. Nonetheless, the domain -wall structure with a localized source is preserved. At the perturbative level, the Kaluza-Klein (KK) tensor gravitational modes are stable and possess a localized massless mode provided the cubic corrections are small compared to the EG braneworld. |
Address |
[Lessa, L. A.; Maluf, R. V.; Silva, J. E. G.; Almeida, C. A. S.] Univ Fed Ceara UFC, Dept Fis, Campus Pici, BR-60455760 Fortaleza, CE, Brazil, Email: leandrolessa@fisica.ufc.br; |
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Thesis |
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Publisher |
IOP Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001240966600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6164 |
Permanent link to this record |
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Author |
Beltran-Palau, P.; Ferreiro, A.; Navarro-Salas, J.; Pla, S. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Breaking of adiabatic invariance in the creation of particles by electromagnetic backgrounds |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
100 |
Issue |
8 |
Pages |
085014 - 12pp |
Keywords |
|
Abstract |
Particles are spontaneously created from the vacuum by time-varying gravitational or electromagnetic backgrounds. It has been proven that the particle number operator in an expanding universe is an adiabatic invariant. In this paper we show that, in some special cases, the expected adiabatic invariance of the particle number fails in presence of electromagnetic backgrounds. In order to do this, we consider as a prototype a Sauter-type electric pulse. Furthermore, we also show a close relation between the breaking of the adiabatic invariance and the emergence of the axial anomaly. |
Address |
[Beltran-Palau, Pau; Ferreiro, Antonio; Navarro-Salas, Jose; Pla, Silvia] Univ Valencia, CSIC, Ctr Mixto, Fac Fis,Dept Fis Teor, E-46100 Valencia, Spain, Email: pau.beltran@uv.es; |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2470-0010 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000491467800009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
4184 |
Permanent link to this record |
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Author |
Angles-Castillo, A.; Perez, A.; Roldan, E. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Bright and dark solitons in a photonic nonlinear quantum walk: lessons from the continuum |
Type |
Journal Article |
Year |
2024 |
Publication |
New Journal of Physics |
Abbreviated Journal |
New J. Phys. |
Volume |
26 |
Issue |
2 |
Pages |
023004 - 16pp |
Keywords |
quantum walks; soliton; non-linear optics |
Abstract |
We propose a nonlinear quantum walk model inspired in a photonic implementation in which the polarization state of the light field plays the role of the coin-qubit. In particular, we take profit of the nonlinear polarization rotation occurring in optical media with Kerr nonlinearity, which allows to implement a nonlinear coin operator, one that depends on the state of the coin-qubit. We consider the space-time continuum limit of the evolution equation, which takes the form of a nonlinear Dirac equation. The analysis of this continuum limit allows us to gain some insight into the existence of different solitonic structures, such as bright and dark solitons. We illustrate several properties of these solitons with numerical calculations, including the effect on them of an additional phase simulating an external electric field. |
Address |
[Angles-Castillo, Andreu; Perez, Armando] Univ Valencia, Dept Fis Teor & IFIC, CSIC, Burjassot 46100, Valencia, Spain, Email: andreu.angles-castillo@uv.es |
Corporate Author |
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Thesis |
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Publisher |
IOP Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1367-2630 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001156767400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
5929 |
Permanent link to this record |
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Author |
Das, B. et al; Algora, A. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Broken seniority symmetry in the semimagic proton mid-shell nucleus 95Rh |
Type |
Journal Article |
Year |
2024 |
Publication |
Physical Review Research |
Abbreviated Journal |
Phys. Rev. Res. |
Volume |
6 |
Issue |
2 |
Pages |
L022038 - 7pp |
Keywords |
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Abstract |
Lifetime measurements of low-lying excited states in the semimagic ( N = 50) nucleus 95 Rh have been performed by means of the fast -timing technique. The experiment was carried out using gamma -ray detector arrays consisting of LaBr 3 (Ce) scintillators and germanium detectors integrated into the DESPEC experimental setup commissioned for the Facility for Antiproton and Ion Research ( FAIR ) Phase -0, Darmstadt, Germany. The excited states in 95 Rh were populated primarily via the /3 decays of 95 Pd nuclei, produced in the projectile fragmentation of a 850 MeV / nucleon 124 Xe beam impinging on a 4 g / cm 2 9 Be target. The deduced electromagnetic E2 transition strengths for the gamma -ray cascade within the multiplet structure depopulating from the isomeric I pi = 21 / 2 + state are found to exhibit strong deviations from predictions of standard shell model calculations which feature approximately conserved seniority symmetry. In particular, the observation of a strongly suppressed E2 strength for the 13 / 2 + -> 9 / 2 + ground state transition cannot be explained by calculations employing standard interactions. This remarkable result may require revision of the nucleon-nucleon interactions employed in state-of-the-art theoretical model calculations, and might also point to the need for including three-body forces in the Hamiltonian. |
Address |
[Das, B.; Cederwall, B.; Qi, C.; Aktas, O.; Liotta, R.; Vasiljevic, J.] KTH Royal Inst Technol, S-10691 Stockholm, Sweden, Email: b.das@gsi.de; |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001240855200002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6147 |
Permanent link to this record |
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Author |
Moreno, O.; Sarriguren, P.; Algora, A.; Fraile, L.M.; Orrigo, S.E.A. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Bulk and decay properties of neutron-deficient odd-mass Hg isotopes near A=185 |
Type |
Journal Article |
Year |
2022 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
106 |
Issue |
3 |
Pages |
034317 - 11pp |
Keywords |
|
Abstract |
Ground and isomeric states of the neutron-deficient odd-A isotopes 183Hg, 185Hg, and 187Hg are described from a microscopic calculation based on a self-consistent, axially deformed Hartree-Fock mean field with the Skyrme functional and pairing within BCS approximation. For each equilibrium shape and different odd-neutron states, results on mean-square charge radii and magnetic dipole moments are given and analyzed in the context of their sensitivity to the nuclear deformation and to the spin and parity. Spin-isospin correlations within proton-neutron quasiparticle random phase approximation are then introduced in the nuclear states to obtain the distributions of Gamow-Teller strength and the beta+/EC half-lives of these isotopes, whose measurements are planned at ISOLDE-CERN using total absorption gamma-ray spectroscopy techniques. |
Address |
[Moreno, O.; Fraile, L. M.] Univ Complutense Madrid, Dept Estruct Mat Fis Term & Elect, Grp Fis Nucl, Av Complutense s-n, E-28040 Madrid, Spain, Email: osmoreno@ucm.es |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9985 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000861758100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5368 |
Permanent link to this record |