Records |
Author |
Olmo, G.J. |
Title |
Palatini approach to modified gravity: f(R) theories and beyond |
Type |
Journal Article |
Year |
2011 |
Publication |
International Journal of Modern Physics D |
Abbreviated Journal ![sorted by Abbreviated Journal field, ascending order (up)](img/sort_asc.gif) |
Int. J. Mod. Phys. D |
Volume |
20 |
Issue |
4 |
Pages |
413-462 |
Keywords |
Palatini formalism; modified gravity; cosmic speed-up; dark energy; dark matter; MOND; quantum gravity phenomenology; Hamiltonian formulation; stellar structure; Cauchy problem; solar system tests |
Abstract |
We review the recent literature on modified theories of gravity in the Palatini approach. After discussing the motivations that lead to consider alternatives to Einstein's theory and to treat the metric and the connection as independent objects, we review several topics that have been recently studied within this framework. In particular, we provide an in-depth analysis of the cosmic speed-up problem, laboratory and solar system tests, the structure of stellar objects, the Cauchy problem, and bouncing cosmologies. We also discuss the importance of going beyond the f(R) models to capture other phenomenological aspects related with dark matter/energy and quantum gravity. |
Address |
[Olmo, Gonzalo J.] Univ Valencia CSIC, Dept Fis Teor, Valencia, Spain, Email: gonzalo.olmo@uv.es |
Corporate Author |
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Thesis |
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Publisher |
World Scientific Publ Co Pte 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 |
0218-2718 |
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:000290228200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
961 |
Permanent link to this record |
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Author |
Capozziello, S.; Harko, T.; Lobo, F.S.N.; Olmo, G.J. |
Title |
Hybrid Modified Gravity Unifying Local Tests, Galactic Dynamics and Late-Time Cosmic Acceleration |
Type |
Journal Article |
Year |
2013 |
Publication |
International Journal of Modern Physics D |
Abbreviated Journal ![sorted by Abbreviated Journal field, ascending order (up)](img/sort_asc.gif) |
Int. J. Mod. Phys. D |
Volume |
22 |
Issue |
12 |
Pages |
1342006 - 7pp |
Keywords |
Modified gravity; late-time cosmic acceleration; dark matter; solar system tests |
Abstract |
The nonequivalence between the metric and Palatini formalisms of f(R) gravity is an intriguing feature of these theories. However, in the recently proposed hybrid metric-Palatini gravity, consisting of the superposition of the metric Einstein-Hilbert Lagrangian with an f(R) term constructed a la Palatini, the “true” gravitational field is described by the interpolation of these two nonequivalent approaches. The theory predicts the existence of a light long-range scalar field, which passes the local constraints and affects the galactic and cosmological dynamics. Thus, the theory opens new possibilities for a unified approach, in the same theoretical framework, to the problems of dark energy and dark matter, without distinguishing a priori matter and geometric sources, but taking their dynamics into account under the same standard. |
Address |
[Capozziello, Salvatore] Univ Naples Federico II, Dipartimento Fis, I-80126 Naples, Italy, Email: capozzie@na.infn.it; |
Corporate Author |
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Thesis |
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Publisher |
World Scientific Publ Co Pte 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 |
0218-2718 |
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:000329048900013 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1688 |
Permanent link to this record |
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Author |
Olmo, G.J.; Rubiera-Garcia, D. |
Title |
The quantum, the geon and the crystal |
Type |
Journal Article |
Year |
2015 |
Publication |
International Journal of Modern Physics D |
Abbreviated Journal ![sorted by Abbreviated Journal field, ascending order (up)](img/sort_asc.gif) |
Int. J. Mod. Phys. D |
Volume |
24 |
Issue |
9 |
Pages |
1542013 - 15pp |
Keywords |
Effective geometries; crystalline structures; modified gravity; metric-affine approach; geons |
Abstract |
Effective geometries arising from a hypothetical discrete structure of spacetime can play an important role in the understanding of the gravitational physics beyond General Relativity (GR). To discuss this question, we make use of lessons from crystalline systems within solid state physics, where the presence of defects in the discrete microstructure of the crystal determine the kind of effective geometry needed to properly describe the system in the macroscopic continuum limit. In this work, we study metric-affine theories with nonmetricity and torsion, which are the gravitational analog of crystalline structures with point defects and dislocations. We consider a crystal-motivated gravitational action and show the presence of topologically nontrivial structures (wormholes) supported by an electromagnetic field. Their existence has important implications for the quantum foam picture and the effective gravitational geometries. We discuss how the dialogue between solid state physics systems and modified gravitational theories can provide useful insights on both sides. |
Address |
[Olmo, Gonzalo J.] Univ Valencia, CSIC, Fac Fis, Dept Fis Teor, E-46100 Valencia, Spain, Email: drubiera@fudan.edu.cn |
Corporate Author |
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Thesis |
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Publisher |
World Scientific Publ Co Pte 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 |
0218-2718 |
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:000358793200014 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2322 |
Permanent link to this record |
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Author |
Cervantes-Cota, J.L.; de Putter, R.; Linder, E.V. |
Title |
Induced gravity and the attractor dynamics of dark energy/dark matter |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal ![sorted by Abbreviated Journal field, ascending order (up)](img/sort_asc.gif) |
J. Cosmol. Astropart. Phys. |
Volume |
12 |
Issue |
12 |
Pages |
019 - 20pp |
Keywords |
modified gravity; dark energy theory |
Abstract |
Attractor solutions that give dynamical reasons for dark energy to act like the cosmological constant, or behavior close to it, are interesting possibilities to explain cosmic acceleration. Coupling the scalar field to matter or to gravity enlarges the dynamical behavior; we consider both couplings together, which can ameliorate some problems for each individually. Such theories have also been proposed in a Higgs-like fashion to induce gravity and unify dark energy and dark matter origins. We explore restrictions on such theories due to their dynamical behavior compared to observations of the cosmic expansion. Quartic potentials in particular have viable stability properties and asymptotically approach general relativity. |
Address |
[Cervantes-Cota, Jorge L.] Inst Nacl Invest Nucl, Dept Fis, Mexico City 11801, DF, Mexico, Email: jorge.cervantes@inin.gob.mx |
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 |
ISI:000286930700019 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
533 |
Permanent link to this record |
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Author |
Girones, Z.; Marchetti, A.; Mena, O.; Pena-Garay, C.; Rius, N. |
Title |
Cosmological data analysis of f(R) gravity models |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal ![sorted by Abbreviated Journal field, ascending order (up)](img/sort_asc.gif) |
J. Cosmol. Astropart. Phys. |
Volume |
11 |
Issue |
11 |
Pages |
004 - 18pp |
Keywords |
modified gravity; cosmological parameters from LSS |
Abstract |
A class of well-behaved modified gravity models with long enough matter domination epoch and a late-time accelerated expansion is confronted with SNIa, CMB, SDSS, BAO and H(z) galaxy ages data, as well as current measurements of the linear growth of structure. We show that the combination of geometrical probes and growth data exploited here allows to rule out f(R) gravity models, in particular, the logarithmic of curvature model. We also apply solar system tests to the models in agreement with the cosmological data. We find that the exponential of the inverse of the curvature model satisfies all the observational tests considered and we derive the allowed range of parameters. Current data still allows for small deviations of Einstein gravity. Future, high precision growth data, in combination with expansion history data, will be able to distinguish tiny modifications of standard gravity from the Lambda CDM model. |
Address |
[Girones, Z.; Marchetti, A.; Mena, O.; Pena-Garay, C.; Rius, N.] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Valencia 46071, Spain, Email: girones@ific.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 |
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 |
ISI:000284825100004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
315 |
Permanent link to this record |