Records |
Author |
Fernandez-Silvestre, D.; Foo, J.; Good, M.R.R. |
Title |
On the duality of Schwarzschild-de Sitter spacetime and moving mirror |
Type |
Journal Article |
Year |
2022 |
Publication |
Classical and Quantum Gravity |
Abbreviated Journal |
Class. Quantum Gravity |
Volume |
39 |
Issue |
5 |
Pages |
055006 - 18pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
QFT in curved spacetime; black holes; cosmological horizons; moving mirrors |
Abstract |
The Schwarzschild-de Sitter (SdS) metric is the simplest spacetime solution in general relativity with both a black hole event horizon and a cosmological event horizon. Since the Schwarzschild metric is the most simple solution of Einstein's equations with spherical symmetry and the de Sitter metric is the most simple solution of Einstein's equations with a positive cosmological constant, the combination in the SdS metric defines an appropriate background geometry for semi-classical investigation of Hawking radiation with respect to past and future horizons. Generally, the black hole temperature is larger than that of the cosmological horizon, so there is heat flow from the smaller black hole horizon to the larger cosmological horizon, despite questions concerning the definition of the relative temperature of the black hole without a measurement by an observer sitting in an asymptotically flat spacetime. Here we investigate the accelerating boundary correspondence of the radiation in SdS spacetime without such a problem. We have solved for the boundary dynamics, energy flux and asymptotic particle spectrum. The distribution of particles is globally non-thermal while asymptotically the radiation reaches equilibrium. |
Address |
[Fernandez-Silvestre, Diego] Univ Valencia, CSIC, Dept Fis Teor, C Dr Moliner 50, Burjassot 46100, Spain, Email: diefer2@alumni.uv.es; |
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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 |
0264-9381 |
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:000754064600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5130 |
Permanent link to this record |
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Author |
Balbinot, R.; Fabbri, A. |
Title |
The Hawking Effect in the Particles-Partners Correlations |
Type |
Journal Article |
Year |
2023 |
Publication |
Physics |
Abbreviated Journal |
Physics |
Volume |
5 |
Issue |
4 |
Pages |
968-982 |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
quantum fields in curved space; black holes; Hawking radiation; correlations across the horizon |
Abstract |
We analyze the correlations functions across the horizon in Hawking black hole radiation to reveal the correlations between Hawking particles and their partners. The effects of the underlying space-time on this are shown in various examples ranging from acoustic black holes to regular black holes. |
Address |
[Balbinot, Roberto] Univ Bologna, Dipartimento Fis, Via Irnerio 46, I-40126 Bologna, Italy, Email: roberto.balbinot@unibo.it; |
Corporate Author |
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Thesis |
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Publisher |
Mdpi |
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:001130983900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5858 |
Permanent link to this record |
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Author |
Casals, M.; Fabbri, A.; Martinez, C.; Zanelli, J. |
Title |
Quantum dress for a naked singularity |
Type |
Journal Article |
Year |
2016 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
760 |
Issue |
|
Pages |
244-248 |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Semiclassical gravity; Quantum backreaction; Cosmic censorship; Black holes; Naked singularities; BTZ |
Abstract |
We investigate semiclassical backreaction on a conical naked singularity space-time with a negative cosmological constant in (2 + 1)-dimensions. In particular, we calculate the renormalized quantum stress-energy tensor for a conformally coupled scalar field on such naked singularity space-time. We then obtain the backreacted metric via the semiclassical Einstein equations. We show that, in the regime where the semiclassical approximation can be trusted, backreaction dresses the naked singularity with an event horizon, thus enforcing (weak) cosmic censorship. |
Address |
[Casals, Marc] Ctr Brasileiro Pesquisas Fis, BR-22290180 Rio De Janeiro, Brazil, Email: mcasals@cbpf.br; |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0370-2693 |
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:000382890500037 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2804 |
Permanent link to this record |
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Author |
Olmo, G.J.; Rubiera-Garcia, D.; Sanchez-Puente, A. |
Title |
Impact of curvature divergences on physical observers in a wormhole space-time with horizons |
Type |
Journal Article |
Year |
2016 |
Publication |
Classical and Quantum Gravity |
Abbreviated Journal |
Class. Quantum Gravity |
Volume |
33 |
Issue |
11 |
Pages |
115007 - 12pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Singularities; black holes; metric-affine geometry |
Abstract |
The impact of curvature divergences on physical observers in a black hole space-time, which, nonetheless, is geodesically complete is investigated. This space-time is an exact solution of certain extensions of general relativity coupled to Maxwell's electrodynamics and, roughly speaking, consists of two Reissner-Nordstrom (or Schwarzschild or Minkowski) geometries connected by a spherical wormhole near the center. We find that, despite the existence of infinite tidal forces, causal contact is never lost among the elements making up the observer. This suggests that curvature divergences may not be as pathological as traditionally thought. |
Address |
[Olmo, Gonzalo J.; Sanchez-Puente, A.] Univ Valencia, CSIC, Ctr Mixto, 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 |
0264-9381 |
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:000377442000010 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2728 |
Permanent link to this record |
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Author |
Araujo Filho, A.A.; Zare, S.; Porffrio, P.J.; Kriz, J.; Hassanabadi, H. |
Title |
Thermodynamics and evaporation of a modified Schwarzschild black hole in a non-commutative gauge theory |
Type |
Journal Article |
Year |
2023 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
838 |
Issue |
|
Pages |
137744 - 9pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Thermodynamic properties; Black hole; Non-commutative gauge theory; Evaporation process |
Abstract |
In this work, we study the thermodynamic properties on a non-commutative background via gravitational gauge field potentials. This procedure is accomplished after contracting de Sitter (dS) group, SO(4, 1), with the Poincare group, ISO(3, 1). Particularly, we focus on a static spherically symmetric black hole. In this manner, we calculate the modified Hawking temperature and the other deformed thermal state quantities, namely, entropy, heat capacity, Helmholtz free energy and pressure. Finally, we also investigate the black hole evaporation process in such a context. |
Address |
[Araujo Filho, A. A.] Univ Valencia, Dept Fis Teor, Burjassot 46100, Valencia, Spain, Email: dilto@fisica.ufc.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 |
0370-2693 |
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:000935398000001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5483 |
Permanent link to this record |
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Author |
Araujo Filho, A.A. |
Title |
Analysis of a regular black hole in Verlinde's gravity |
Type |
Journal Article |
Year |
2024 |
Publication |
Classical and Quantum Gravity |
Abbreviated Journal |
Class. Quantum Gravity |
Volume |
41 |
Issue |
1 |
Pages |
015003 - 30pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Verlinde's emergent gravity; dark matter; shadows; black hole |
Abstract |
This work focuses on the examination of a regular black hole within Verlinde's emergent gravity, specifically investigating the Hayward-like (modified) solution. The study reveals the existence of three horizons under certain conditions, i.e. an event horizon and two Cauchy horizons. Our results indicate regions which phase transitions occur based on the analysis of heat capacity and Hawking temperature. To compute the latter quantity, we utilize three distinct methods: the surface gravity approach, Hawking radiation, and the application of the first law of thermodynamics. In the case of the latter approach, it is imperative to introduce a correction to ensure the preservation of the Bekenstein-Hawking area law. Geodesic trajectories and critical orbits (photon spheres) are calculated, highlighting the presence of three light rings. Additionally, we investigate the black hole shadows. Furthermore, the quasinormal modes are explored using third- and sixth-order Wentzel-Kramers-Brillouin approximations. In particular, we observe stable and unstable oscillations for certain frequencies. Finally, in order to comprehend the phenomena of time-dependent scattering in this scenario, we provide an investigation of the time-domain solution. |
Address |
[Araujo Filho, A. A.] Univ Valencia, Ctr Mixto Univ Valencia, CSIC, Dept Fis Teor, Burjassot 46100, Valencia, Spain, Email: dilto@fisica.ufc.br |
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 |
0264-9381 |
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:001114102700001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5841 |
Permanent link to this record |
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Author |
Santos, A.C.L.; Muniz, C.R.; Maluf, R.V. |
Title |
Yang-Mills Casimir wormholes in D=2+1 |
Type |
Journal Article |
Year |
2023 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
09 |
Issue |
9 |
Pages |
022 - 24pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Wormholes; Exact solutions; black holes and black hole thermodynamics in GR and beyond; gravity |
Abstract |
This work presents new three-dimensional traversable wormhole solutions sourced by the Casimir density and pressures related to the quantum vacuum fluctuations in Yang-Mills (Y-M) theory. We begin by analyzing the noninteracting Y-M Casimir wormholes, initially considering an arbitrary state parameter omega and determine a simple constant wormhole shape function. Next, we introduce a new methodology for deforming the state parameter to find well-behaved redshift functions. The wormhole can be interpreted as a legitimate Casimir wormhole with an expected average state parameter of omega = 2. Then, we investigate the wormhole curvature properties, energy conditions, and stability. Furthermore, we discover a novel family of traversable wormhole solutions sourced by the quantum vacuum fluctuations of interacting Yang-Mills fields with a more complex shape function. Deforming the effective state parameter similarly, we obtain well-behaved redshift functions and traversable wormhole solutions. Finally, we examine the energy conditions and stability of solutions in the interacting scenario and compare to the noninteracting case. |
Address |
[Santos, Alana C. L.; Maluf, Roberto V.] Univ Fed Ceara UFC, Departamento Fis, Campus Pici,6030, BR-60455760 Fortaleza, Ceara, Brazil, Email: alanasantos@fisica.ufc.br; |
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:001196198800004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6031 |
Permanent link to this record |