| Weekly Seminars for July 2016 |
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Wednesday July 20th,
2016 - 4,00 pm
ICRANet Pescara
ICRANet Seminar
Speaker: Prof. Sang Pyo Kim
Institution: Dept. of Physics, Kunsan National University, Kunsan 54150 , Korea Title: Pair Production from Charged Black Holes
Abstract:
The Reissner-Nordstrom (RN) and Kerr-Newman (KN) black hole has a tiny Hawking temperature in the extremal limit and the Hawking radiation is thus exponentially suppressed except for those with the energy exactly equal to the chemical potential. The near-extremal black hole, however, can emit charged particles through the Schwinger mechanism, pair creation by an electric field. Remarkably, the near-horizon geometry is AdS_2 x S^2 for a near-extremal RN black hole and warped AdS_3 x S^1 for a near-extremal KN black hole. Using the AdS symmetry, the pair-production rate can be explicitly calculated for the near-extremal RN and KN black hole. Remarkably, the pair production in the extremal black hole has a thermal interpretation, in which an effective temperature of the Unruh effect and the AdS_2 curvature introduced by Cai and Kim governs the formula. The near-extremal black hole has an additional factor, which exhibits the QED effect in Rindler space coming from a small deviation from the exact extremality. It is shown that the universal feature of the Schwinger effect in a near-extremal black hole seems to be persistent regardless of rotation or dimensions. Black hole thermodynamics, in particular, the entropy of extremal black hole is discussed.
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ICRANet Secretariat
ICRANet Piazza della Repubblica 10 65122 Pescara (PE) Italy tel.: +39 085 23054200 fax: +39 085 4219252 email: secretariat@icranet.org
Friday, July 22th, 2016 - 11,00 am
ICRANet Pescara
ICRANet Seminar
Speaker: Prof. Donato Giorgio Torrieri
Institution: Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, Campinas, São Paulo , Brazil Title: Hydrodynamics as an effective theory
Abstract:
We attempt to derive hydrodynamics as an effective bottom-up theory, without reference to any microscopic dynamics, in order to understand if symmetries and quantum mechanics gjve "universal limits" to hydrodynamic and transport properties of any physical system. We describe how ideal, Navier Stokes and Israel-Stewart hydrodynamics can be obtained in this way, and show how a systematic further expansion can be constructed and investigated.
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ICRANet Secretariat
ICRANet Piazza della Repubblica 10 65122 Pescara (PE) Italy tel.: +39 085 23054200 fax: +39 085 4219252 |