Records |
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Nascimento, J.R.; Olmo, G.J.; Petrov, A.Y.; Porfirio, P.J. |
Title |
On metric-affine bumblebee model coupled to scalar matter |
Type |
Journal Article |
Year |
2024 |
Publication |
Nuclear Physics B |
Abbreviated Journal |
Nucl. Phys. B |
Volume |
1004 |
Issue |
|
Pages |
116577 - 10pp |
Keywords |
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Abstract |
We consider the coupling of the metric-affine bumblebee gravity model to scalar matter and calculate the lower -order contributions to two -point functions of bumblebee and scalar fields in the weak gravity approximation. We also obtain the one -loop effective potentials for both scalar and vector fields. |
Address |
[Nascimento, J. R.; Petrov, A. Yu.; Porfirio, P. J.] Univ Fed Paraiba, Dept Fis, Caixa Postal 5008, BR-58051970 Joao Pessoa, PB, Brazil, Email: jroberto@fisica.ufpb.br; |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0550-3213 |
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:001248177100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6157 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Nascimento, J.R.; Olmo, G.J.; Porfirio, P.J.; Petrov, A.Y.; Soares, A.R. |
Title |
Global monopole in Palatini f(R) gravity |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
99 |
Issue |
6 |
Pages |
064053 - 11pp |
Keywords |
|
Abstract |
We consider the space-time metric generated by a global monopole in an extension of general relativity (GR) of the form f(R) = R – lambda R-2. The theory is formulated in the metric-affine (or Palatini) formalism, and exact analytical solutions are obtained. For lambda < 0, one finds that the solution has the same characteristics as the Schwarzschild black hole with a monopole charge in Einstein's GR. For lambda > 0, instead, the metric is more closely related to the Reissner-Nordstrom metric with a monopole charge and, in addition, it possesses a wormhole-like structure that allows for the geodesic completeness of the spacetime. Our solution recovers the expected limits when lambda = 0 and also at the asymptotic far limit. The angular deflection of light in this space-time in the weak field regime is also calculated. |
Address |
[Nascimento, J. R.; Petrov, A. Yu; Soares, A. R.] Univ Fed Paraiba, Dept Fis, Caixa Postal 5008, BR-58051970 Joao Pessoa, Paraiba, Brazil, Email: jroberto@fisica.ufpb.br; |
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 |
|
Notes |
WOS:000462920100010 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3966 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Nascimento, J.R.; Olmo, G.J.; Porfirio, P.J.; Petrov, A.Y.; Soares, A.R. |
Title |
Nonlinear sigma-models in the Eddington-inspired Born-Infeld gravity |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
101 |
Issue |
6 |
Pages |
064043 - 11pp |
Keywords |
|
Abstract |
In this paper we consider two different nonlinear sigma-models minimally coupled to Eddington-inspired Born-Infeld gravity. We show that the resultant geometries represent minimal modifications with respect to those found in GR, though with important physical consequences. In particular, wormhole structures always arise, though this does not guarantee by itself the geodesic completeness of those space-times. In one of the models, quadratic in the canonical kinetic term, we identify a subset of solutions which are regular everywhere and are geodesically complete. We discuss characteristic features of these solutions and their dependence on the relationship between mass and global charge. |
Address |
[Nascimento, J. R.; Porfirio, P. J.; Petrov, A. Yu; Soares, A. R.] Univ Fed Paraiba, Dept Fis, Caixa Postal 5008, BR-58051970 Joao Pessoa, Paraiba, Brazil, Email: jroberto@fisica.ufpb.br; |
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:000521099300008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4344 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Odintsov, S.D.; Olmo, G.J.; Rubiera-Garcia, D. |
Title |
Born-Infeld gravity and its functional extensions |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
90 |
Issue |
4 |
Pages |
044003 - 8pp |
Keywords |
|
Abstract |
We investigate the dynamics of a family of functional extensions of the (Eddington-inspired) Born-Infeld gravity theory, constructed with the inverse of the metric and the Ricci tensor. We provide a generic formal solution for the connection and an Einstein-like representation for the metric field equations of this family of theories. For particular cases we consider applications to the early-time cosmology and find that nonsingular universes with a cosmic bounce are very generic and robust solutions. |
Address |
[Odintsov, Sergei D.] Inst Catalana Recerca & Estudis Avancats, Barcelona 08010, Spain, Email: gonzalo.olmo@csic.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 |
1550-7998 |
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:000339999700005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1880 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Olmo, G.J. |
Title |
Palatini actions and quantum gravity phenomenology |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
10 |
Issue |
10 |
Pages |
018 - 15pp |
Keywords |
quantum gravity phenomenology; cosmic singularity |
Abstract |
We show that an invariant an universal length scale can be consistently introduced in a generally covariant theory through the gravitational sector using the Palatini approach. The resulting theory is able to capture different aspects of quantum gravity phenomenology in a single framework. In particular, it is found that in this theory field excitations propagating with different energy-densities perceive different background metrics, which is a fundamental characteristic of the DSR and Rainbow Gravity approaches. We illustrate these properties with a particular gravitational model and explicitly show how the soccer ball problem is avoided in this framework. The isotropic and anisotropic cosmologies of this model also avoid the big bang singularity by means of a big bounce. |
Address |
[Olmo, GJ] Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain, Email: gonzalo.olmo@csic.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 |
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:000296767600018 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
816 |
Permanent link to this record |