Records |
Author ![sorted by Author field, descending order (down)](img/sort_desc.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 |
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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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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, descending order (down)](img/sort_desc.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, descending order (down)](img/sort_desc.gif) |
Napiralla, P. et al; Domingo-Pardo, C. |
Title |
Benchmarking the PreSPEC@GSI experiment for Coulex-multipolarimetry on the pi(p3/2) -> pi(p1/2) spin-flip transition in 85Br |
Type |
Journal Article |
Year |
2020 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
Volume |
56 |
Issue |
5 |
Pages |
147 - 10pp |
Keywords |
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Abstract |
A first performance test of the Coulomb excitation multipolarimetry (Coulex-multipolarimetry) method is presented. It is based on a 85Br pp3/ 2. pp1/ 2 spinflip experiment performed as part of the PreSPEC-AGATA campaign at the GSI Helmholtzzentrum fur Schwerionen-forschung (GSI). Via determination of background levels around the expected 85Br excitations as well as measured 197Au excitations, an upper limit for the M1 transition strength of the 1/2- 1. 3/2- g.s. transition in 85Br and a lower beam time limit for upcoming experimental campaigns utilizing Coulex-multipolarimetry have been inferred. The impact of the use of AGATA in its anticipated 1p configuration on these estimates is deduced via Geant4 simulations. |
Address |
[Napiralla, P.; Lettmann, M.; Stahl, C.; Pietralla, N.; Boutachkov, P.; Cortes, M. L.; John, P. R.; Lizarazo, C.; Louchart-Henning, C.; Merchan, E.; Moeller, O.; Moeller, T.; Ralet, D.; Werner, V] Tech Univ Darmstadt, Inst Kernphys, Schlossgartenstr 9, D-64289 Darmstadt, Germany, Email: pnapiralla@ikp.tu-darmstadt.de |
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Publisher |
Springer |
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 |
1434-6001 |
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:000541855500002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4441 |
Permanent link to this record |
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Author ![sorted by Author field, descending order (down)](img/sort_desc.gif) |
Nadal-Gisbert, S.; Navarro-Salas, J.; Pla, S. |
Title |
Low-energy states and CPT invariance at the big bang |
Type |
Journal Article |
Year |
2023 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
107 |
Issue |
8 |
Pages |
085018 - 16pp |
Keywords |
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Abstract |
In this paper, we analyze the quantum vacuum in a radiation-dominated and CPT -invariant universe by further imposing the quantum states to be ultraviolet regular i.e., satisfying the Hadamard/adiabatic condition. For scalar fields, this is enforced by constructing the vacuum via the states of low-energy proposal. For spin -12 fields, we extend this proposal for a FLRW spacetime and apply it for the radiation-dominated and CPT -invariant universe. We focus on minimizing the smeared energy density around the big bang and give strong evidence that the resulting states satisfy the Hadamard/adiabatic condition. These states are then self -consistent candidates as effective big bang quantum vacuum from the field theory perspective. |
Address |
[Nadal-Gisbert, Sergi; Navarro-Salas, Jose] Univ Valencia, Ctr Mixto Univ Valencia, CSIC Fac Fis, Dept Fis Teor, Valencia 46100, Spain, Email: sergi.nadal@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:000981997800003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5585 |
Permanent link to this record |
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Author ![sorted by Author field, descending order (down)](img/sort_desc.gif) |
Nada, A.; Ramos, A. |
Title |
An analysis of systematic effects in finite size scaling studies using the gradient flow |
Type |
Journal Article |
Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
81 |
Issue |
1 |
Pages |
1 - 19pp |
Keywords |
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Abstract |
We propose a new strategy for the determination of the step scaling function sigma (u) in finite size scaling studies using the gradient flow. In this approach the determination of sigma (u) is broken in two pieces: a change of the flow time at fixed physical size, and a change of the size of the system at fixed flow time. Using both perturbative arguments and a set of simulations in the pure gauge theory we show that this approach leads to a better control over the continuum extrapolations. Following this new proposal we determine the running coupling at high energies in the pure gauge theory and re-examine the determination of the Lambda -parameter, with special care on the perturbative truncation uncertainties. |
Address |
[Nada, Alessandro] DESY, John von Neumann Inst Comp NIC, Platanenallee 6, D-15738 Zeuthen, Germany, Email: alberto.ramos@cern.ch |
Corporate Author |
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Thesis |
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Publisher |
Springer |
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 |
1434-6044 |
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:000606481000001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4678 |
Permanent link to this record |