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Author Balbinot, R.; Fabbri, A.
Title Amplifying the Hawking Signal in BECs Type Journal Article
Year 2014 Publication (up) 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 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 Babichev, E.; Fabbri, A.
Title Instability of black holes in massive gravity Type Journal Article
Year 2013 Publication (up) Classical and Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 30 Issue 15 Pages 152001 - 7pp
Keywords
Abstract We show that linear perturbations around the simplest black hole solution of massive bi-gravity theories, the bi-Schwarzschild solution, exhibit an unstable mode featuring the Gregory-Laflamme instability of higher dimensional black strings. The result is obtained for the massive gravity theory which is free from the Boulware-Deser ghost, as well as for its extension with two dynamical metrics. These results may indicate that static black holes in massive gravity do not exist. For the graviton mass of the order of the Hubble scale, however, the instability timescale is of order of the Hubble time.
Address [Babichev, Eugeny] Univ Paris 11, Lab Phys Theor Orsay, F-91405 Orsay, France, Email: eugeny.babichev@th.u-psud.fr;
Corporate Author Thesis
Publisher 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 0264-9381 ISBN Medium
Area Expedition Conference
Notes WOS:000321692600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1498
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Author Clement, G.; Fabbri, A.
Title A scenario for critical scalar field collapse in AdS(3) Type Journal Article
Year 2015 Publication (up) Classical and Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 32 Issue 9 Pages 095009 - 16pp
Keywords critical collapse; exact solutions; AdS(3)
Abstract We present a family of exact solutions, depending on two parameters alpha and b (related to the scalar field strength), to the three-dimensional Einstein-scalar field equations with negative cosmological constant Lambda. For b not equal 0 these solutions reduce to the static Banados-Teitelboim-Zanelli (BTZ) family of vacuum solutions, with mass M = -alpha. For b not equal 0, the solutions become dynamical and develop a strong spacelike central singularity. The alpha < 0 solutions are black-hole like, with a global structure topologically similar to that of the BTZ black holes, and a finite effective mass. We show that the near-singularity behavior of the solutions with alpha > 0 agrees qualitatively with that observed in numerical simulations of sub-critical collapse, including the independence of the near-critical regime on the angle deficit of the spacetime. We analyze in the Lambda = 0 approximation the linear perturbations of the self-similar threshold solution, alpha = 0, and find that it has only one unstable growing mode, which qualifies it as a candidate critical solution for scalar field collapse.
Address [Clement, Gerard] Univ Savoie, CNRS, LAPTh, F-74941 Annecy Le Vieux, France, Email: gerard.clement@lapth.cnrs.fr;
Corporate Author Thesis
Publisher 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 0264-9381 ISBN Medium
Area Expedition Conference
Notes WOS:000353351500009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2192
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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 (up) 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 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 (up) 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 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 (up) 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 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 (up) 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 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
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Author Babichev, E.; Fabbri, A.
Title A class of charged black hole solutions in massive (bi)gravity Type Journal Article
Year 2014 Publication (up) Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 016 - 10pp
Keywords Classical Theories of Gravity; Black Holes
Abstract We present a new class of solutions describing charged black holes in massive (bi)gravity. For a generic choice of the parameters of the massive gravity action, the solution is the Reissner-Nordstrom-de Sitter metric written in the Eddington-Finkelstein coordinates for both metrics. We also study a special case of the parameters, for which the space of solutions contains an extra symmetry.
Address [Babichev, Eugeny] Univ Paris 11, CNRS, LPT, UMR 8627, F-91405 Orsay, France, Email: eugeny.babichev@th.u-psud.fr;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000339110500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1847
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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 (up) 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 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 Martone, G.I.; Larre, P.E.; Fabbri, A.; Pavloff, N.
Title Momentum distribution and coherence of a weakly interacting Bose gas after a quench Type Journal Article
Year 2018 Publication (up) Physical Review A Abbreviated Journal Phys. Rev. A
Volume 98 Issue 6 Pages 063617 - 21pp
Keywords
Abstract We consider a weakly interacting uniform atomic Bose gas with a time-dependent nonlinear coupling constant. By developing a suitable Bogoliubov treatment we investigate the time evolution of several observables, including the momentum distribution, the degree of coherence in the system, and their dependence on dimensionality and temperature. We rigorously prove that the low-momentum Bogoliubov modes remain frozen during the whole evolution, while the high-momentum ones adiabatically follow the change in time of the interaction strength. At intermediate momenta we point out the occurrence of oscillations, which are analogous to Sakharov oscillations. We identify two wide classes of time-dependent behaviors of the coupling for which an exact solution of the problem can be found, allowing for an analytic computation of all the relevant observables. A special emphasis is put on the study of the coherence property of the system in one spatial dimension. We show that the system exhibits a smooth “light-cone effect,” with typically no prethermalization.
Address [Martone, Giovanni I.; Pavloff, Nicolas] Univ Paris Saclay, Univ Paris Sud, CNRS, LPTMS,UMR 8626, F-91405 Orsay, 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 2469-9926 ISBN Medium
Area Expedition Conference
Notes WOS:000452949900009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3841
Permanent link to this record