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Author Balbinot, R.; Fabbri, A.; Dudley, R.A.; Anderson, P.R.
Title Particle production in the interiors of acoustic black holes Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 10 Pages 105021 - 13pp
Keywords
Abstract Phonon creation inside the horizons of acoustic black holes is investigated using two simple toy models. It is shown that, unlike what occurs in the exterior regions, the spectrum is not thermal. This nonthermality is due to the anomalous scattering that occurs in the interior regions.
Address [Balbinot, Roberto] Univ Bologna, Dipartimento Fis, Via Irnerio 46, I-40126 Bologna, Italy, Email: balbinot@bo.infn.it;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000498879600007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4209
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Author Casals, M.; Fabbri, A.; Martinez, C.; Zanelli, J.
Title Quantum-corrected rotating black holes and naked singularities in (2+1) dimensions Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue 10 Pages 104023 - 39pp
Keywords
Abstract We analytically investigate the perturbative effects of a quantum conformally coupled scalar field on rotating (2 + 1)-dimensional black holes and naked singularities. In both cases we obtain the quantum-back-reacted metric analytically. In the black hole case, we explore the quantum corrections on different regions of relevance for a rotating black hole geometry. We find that the quantum effects lead to a growth of both the event horizon and the ergosphere, as well as to a reduction of the angular velocity compared to their corresponding unperturbed values. Quantum corrections also give rise to the formation of a curvature singularity at the Cauchy horizon and show no evidence of the appearance of a superradiant instability. In the naked singularity case, quantum effects lead to the formation of a horizon that hides the conical defect, thus turning it into a black hole. The fact that these effects occur not only for static but also for spinning geometries makes a strong case for the role of quantum mechanics as a cosmic censor in Nature.
Address [Casals, Marc] CBPF, BR-22290180 Rio De Janeiro, Brazil, Email: mcasals@cbpf.br;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000509560700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4263
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Author Dudley, R.A.; Fabbri, A.; Anderson, P.R.; Balbinot, R.
Title Correlations between a Hawking particle and its partner in a 1+1D Bose-Einstein condensate analog black hole Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 102 Issue 10 Pages 105005 - 12pp
Keywords
Abstract The Fourier transform of the density-density correlation function in a Bose-Einstein condensate (BEC) analog black hole is a useful tool to investigate correlations between the Hawking particles and their partners. It can be expressed in terms of <(out)(a) over cap (ext)(up) (out)(a) over cap (int)(up)> where (out)(a) over cap (ext)(up) is the annihilation operator for the Hawking particle and (out)(a) over cap (int)(up) is the corresponding one for the partner. This basic quantity is calculated for three different models for the BEC flow. It is shown that in each model the inclusion of the effective potential in the mode equations makes a significant difference. Furthermore, particle production induced by this effective potential in the interior of the black hole is studied for each model and shown to be nonthermal. An interesting peak that is related to the particle production and is present in some models is discussed.
Address [Dudley, Richard A.; Anderson, Paul R.] Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA, Email: dudlra13@wfu.edu;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000584963300005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4590
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Author Anderson, P.R.; Siahmazgi, S.G.; Clark, R.D.; Fabbri, A.
Title Method to compute the stress-energy tensor for a quantized scalar field when a black hole forms from the collapse of a null shell Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 102 Issue 12 Pages 125035 - 26pp
Keywords
Abstract A method is given to compute the stress-energy tensor for a massless minimally coupled scalar field in a spacetime where a black hole forms from the collapse of a spherically symmetric null shell in four dimensions. Part of the method involves matching the modes for the in vacuum state to a complete set of modes in Schwarzschild spacetime. The other part involves subtracting from the unrenormalized expression for the stress-energy tensor when the field is in the in vacuum state, the corresponding expression when the field is in the Unruh state and adding to this the renormalized stress-energy tensor for the field in the Unruh state. The method is shown to work in the two-dimensional case where the results are known.
Address [Anderson, Paul R.; Siahmazgi, Shohreh Gholizadeh; Clark, Raymond D.] Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA, Email: anderson@wfu.edu;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language Spanish Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000604246500005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4673
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Author Balbinot, R.; Fabbri, A.
Title Quantum correlations across the horizon in acoustic and gravitational black holes Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 105 Issue 4 Pages 045010 - 20pp
Keywords
Abstract We investigate, within the framework of quantum field theory in curved space, the correlations across the horizon of a black hole in order to highlight the particle-partner pair creation mechanism at the origin of Hawking radiation. The analysis concerns both acoustic black holes, formed by Bose-Einstein condensates, and gravitational black holes. More precisely, we have considered a typical acoustic black hole metric with two asymptotic homogeneous regions and the Schwarzschild metric as describing a gravitational black hole. By considering equal-time correlation functions, we find a striking disagreement between the two cases: the expected characteristic peak centered along the trajectories of the Hawking particles and their partners seems to appear only for the acoustic black hole and not for the gravitational Schwarzschild one. The reason for that is the existence of a quantum atmosphere displaced from the horizon as the locus of origin of Hawking radiation together, and this is the crucial aspect, with the presence of a central singularity in the gravitational case swallowing everything is trapped inside the horizon. Correlations, however, are not absent in the gravitational case; to see them, one simply has to consider correlation functions at unequal times, which indeed display the expected peak.
Address [Balbinot, Roberto] Univ Bologna, Dipartimento Fis, Bologna, Italy, Email: balbinot@bo.infn.it;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000761172600005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5156
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Author Fourdrinoy, J.; Robertson, S.; James, N.; Fabbri, A.; Rousseaux, G.
Title Correlations on weakly time-dependent transcritical white-hole flows Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 105 Issue 8 Pages 085022 - 14pp
Keywords
Abstract We report observations made on a run of transcritical flows over an obstacle in a narrow channel. Downstream from the obstacle, the flows decelerate from supercritical to subcritical, typically with an undulation on the subcritical side (known in hydrodynamics as an undular hydraulic jump). In the Analogue Gravity context, this transition corresponds to a white-hole horizon. Free-surface deformations are analyzed, mainly via the two-point correlation function which shows the presence of a checkerboard pattern in the vicinity of the undulation. In nongated flows where the white-hole horizon occurs far downstream from the obstacle, this checkerboard pattern is shown to be due to low-frequency fluctuations associated with slow longitudinal movement of the undulation. Tt can thus be considered as an artifact due to a time-varying background. In gated flows, however, the undulation is typically “attached” to the obstacle, and the fluctuations associated with its movement are strongly suppressed. In this case, the observed correlation pattern is likely due to a stochastic ensemble of surface waves, scattering on a background that is essentially stationary.
Address [Fourdrinoy, Johan; Rousseaux, Germain] Univ Poitiers, CNRS, Inst Pprime, ISAL ENSMA, TSA 51124, F-86073 Poitiers 9, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000810510200011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5274
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Author Fabbri, A.; Pavloff, N.
Title Momentum correlations as signature of sonic Hawking radiation in Bose-Einstein condensates Type Journal Article
Year 2018 Publication Scipost Physics Abbreviated Journal SciPost Phys.
Volume 4 Issue 4 Pages 019 - 45pp
Keywords
Abstract We study the two-body momentum correlation signal in a quasi one dimensional Bose-Einstein condensate in the presence of a sonic horizon. We identify the relevant correlation lines in momentum space and compute the intensity of the corresponding signal. We consider a set of different experimental procedures and identify the specific issues of each measuring process. We show that some inter-channel correlations, in particular the Hawking quantum-partner one, are particularly well adapted for witnessing quantum non-separability, being resilient to the effects of temperature and/or quantum quenches.
Address [Fabbri, Alessandro] Museo Stor Fis & Ctr Studi & Ric Enrico Fermi, Ctr Fermi, Piazza Viminale 1, I-00184 Rome, Italy
Corporate Author Thesis
Publisher Scipost Foundation Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2542-4653 ISBN Medium
Area Expedition Conference
Notes WOS:000432739900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3583
Permanent link to this record