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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 (up) 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 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 Balbinot, R.; Fabbri, A.
Title Amplifying the Hawking Signal in BECs Type Journal Article
Year 2014 Publication Advances in High Energy Physics Abbreviated Journal Adv. High. Energy Phys.
Volume 2014 Issue Pages 713574 - 8pp
Keywords
Abstract We consider simple models of Bosep-Einstein condensates to study analog pairp-creation effects, namely, the Hawking effect from acoustic black holes and the dynamical Casimir effect in rapidly timep-dependent backgrounds. We also focus on a proposal by Cornell to amplify the Hawking signal in density-density correlators by reducing the atoms' interactions shortly before measurements are made.
Address [Balbinot, Roberto; Fabbri, Alessandro] Univ Bologna, Dipartimento Fis, I-40126 Bologna, Italy, Email: afabbri@ific.uv.es
Corporate Author Thesis
Publisher (up) Hindawi Publishing Corporation Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1687-7357 ISBN Medium
Area Expedition Conference
Notes WOS:000335740300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1787
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Author Mayoral, C.; Recati, A.; Fabbri, A.; Parentani, R.; Balbinot, R.; Carusotto, I.
Title Acoustic white holes in flowing atomic Bose-Einstein condensates Type Journal Article
Year 2011 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 13 Issue Pages 025007 - 29pp
Keywords
Abstract We study acoustic white holes in a steadily flowing atomic Bose-Einstein condensate. A white hole configuration is obtained when the flow velocity goes from a super-sonic value in the upstream region to a sub-sonic one in the downstream region. The scattering of phonon wavepackets on a white hole horizon is numerically studied in terms of the Gross-Pitaevskii equation of mean-field theory: dynamical stability of the acoustic white hole is found, as well as a signature of a nonlinear back-action of the incident phonon wavepacket onto the horizon. The correlation pattern of density fluctuations is numerically studied by means of the truncated-Wigner method, which includes quantum fluctuations. Signatures of the white hole radiation of correlated phonon pairs by the horizon are characterized; analogies and differences with Hawking radiation from acoustic black holes are discussed. In particular, a short wavelength feature is identified in the density correlation function, whose amplitude steadily grows in time since the formation of the horizon. The numerical observations are quantitatively interpreted by means of an analytical Bogoliubov theory of quantum fluctuations for a white hole configuration within the step-like horizon approximation.
Address [Recati, Alessio; Carusotto, Iacopo] Univ Trent, INO CNR BEC Ctr, I-38123 Povo, Italy, Email: carusott@science.unitn.it
Corporate Author Thesis
Publisher (up) Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes ISI:000287855400003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 556
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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 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 Thesis
Publisher (up) Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001130983900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5858
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Author Balbinot, R.; Fabbri, A.
Title The Unruh Vacuum and the “In-Vacuum” in Reissner-Nordström Spacetime Type Journal Article
Year 2024 Publication Universe Abbreviated Journal Universe
Volume 10 Issue 1 Pages 18 - 14pp
Keywords Hawking radiation; Unruh vacuum; Reissner-Nordstrom black holes
Abstract The Unruh vacuum is widely used as a quantum state to describe black hole evaporation since, near the horizon, it reproduces the physical state of a quantum field, the so-called “in-vacuum”, in the case where a black hole is formed by gravitational collapse. We examine the relation between these two quantum states in the background spacetime of a Reissner-Nordstrom black hole (both extremal and not), highlighting the similarities and striking differences.
Address [Balbinot, Roberto] Univ Bologna, Dipartimento Fis, Via Irnerio 46, I-40126 Bologna, Italy, Email: roberto.balbinot@unibo.it;
Corporate Author Thesis
Publisher (up) Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001151025300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5914
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Author Carusotto, I.; Balbinot, R.; Fabbri, A.; Recati, A.
Title Density correlations and analog dynamical Casimir emission of Bogoliubov phonons in modulated atomic Bose-Einstein condensates Type Journal Article
Year 2010 Publication European Physical Journal D Abbreviated Journal Eur. Phys. J. D
Volume 56 Issue 3 Pages 391-404
Keywords
Abstract We present a theory of the density correlations that appear in an atomic Bose-Einstein condensate as a consequence of the emission of correlated pairs of Bogoliubov phonons by a time-dependent atom-atom scattering length. This effect can be considered as a condensed matter analog of the dynamical Casimir effect of quantum field theory. Different regimes as a function of the temporal shape of the modulation are identified and a simple physical picture of the phenomenon is discussed. Analytical expressions for the density correlation function are provided for the most significant limiting cases. This theory is able to explain some unexpected features recently observed in numerical studies of analog Hawking radiation from acoustic black holes.
Address [Carusotto, I.; Recati, A.] Univ Trent, CNR, INFM, BEC Ctr, I-38050 Trento, Italy, Email: carusott@science.unitn.it
Corporate Author Thesis
Publisher (up) Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6060 ISBN Medium
Area Expedition Conference
Notes ISI:000274327600013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 506
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Author Balbinot, R.; Fabbri, A.; Mayoral, C.
Title Hawking effect in BECs acoustic white holes Type Journal Article
Year 2013 Publication European Physical Journal Plus Abbreviated Journal Eur. Phys. J. Plus
Volume 128 Issue 2 Pages 16 - 21pp
Keywords
Abstract Bogoliubov pseudoparticle creation in a BEC undergoing a WH-like flow is investigated analytically in the case of a one-dimensional geometry with stepwise homogeneous regions. Comparison of the results with those corresponding to a BH flow is performed. The implications for the analogous gravitational problem is discussed.
Address [Balbinot, R.; Fabbri, A.] Univ Bologna, Dipartimento Fis, I-40126 Bologna, Italy, Email: balbinot@bo.infn.it;
Corporate Author Thesis
Publisher (up) Springer Heidelberg Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-5444 ISBN Medium
Area Expedition Conference
Notes WOS:000316122600005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1378
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Author Mauro, S.; Balbinot, R.; Fabbri, A.; Shapiro, I.L.
Title Fourth derivative gravity in the auxiliary fields representation and application to the black-hole stability Type Journal Article
Year 2015 Publication European Physical Journal Plus Abbreviated Journal Eur. Phys. J. Plus
Volume 130 Issue 7 Pages 135 - 8pp
Keywords
Abstract We consider an auxiliary fields formulation for the general fourth-order gravity on an arbitrary curved background. The case of a Ricci-flat background is elaborated in detail and it is shown that there is an equivalence with the standard metric formulation. At the same time, using auxiliary fields helps to make perturbations to look simpler and the results clearer. As an application we reconsider the linear perturbations for the classical Schwarzschild solution. We also briefly discuss the relation to the effect of massive unphysical ghosts in the theory.
Address [Mauro, Sebastiao; Shapiro, Ilya L.] Univ Fed Juiz de Fora, Dept Fis, ICE, BR-36036360 Juiz De Fora, MG, Brazil, Email: afabbri@ific.uv.es
Corporate Author Thesis
Publisher (up) Springer Heidelberg Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-5444 ISBN Medium
Area Expedition Conference
Notes WOS:000358147100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2309
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Author Balbinot, R.; Carusotto, I.; Fabbri, A.; Recati, A.
Title Testing Hawking Particle Creation By Black Holes Through Correlation Measurements Type Journal Article
Year 2010 Publication International Journal of Modern Physics D Abbreviated Journal Int. J. Mod. Phys. D
Volume 19 Issue 14 Pages 2371-2377
Keywords
Abstract Hawking's prediction of thermal radiation by black holes has been shown by Unruh to be expected also in condensed matter systems. We show here that in a black hole-like configuration realized in a BEC this particle-creation does indeed take place and can be unambiguously identified via a characteristic pattern in the density-density correlations. This opens the concrete possibility of the experimental verification of this effect.
Address [Balbinot, R.] Univ Bologna, Dipartimento Fis, I-40126 Bologna, Italy, Email: balbinot@bo.infn.it
Corporate Author Thesis
Publisher (up) World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0218-2718 ISBN Medium
Area Expedition Conference
Notes ISI:000286112000022 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 534
Permanent link to this record