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SUMMARY:Extreme Black Holes: Anabasis and Accidental Symmetry
DESCRIPTION:  \n \n  \nSpeaker: Achilleas Porfyriadis\, Harvard Black Hole Initiative \nTitle: Extreme Black Holes: Anabasis and Accidental Symmetry \nAbstract: The near-horizon region of black holes near extremality is universally AdS_2-like. In this talk I will concentrate on the simplest example of  AdS_2 x S^2 as the near-horizon of (near-)extreme Reissner-Nordstrom. I will first explain the SL(2)transformation properties of the spherically symmetric linear perturbations of  AdS_2 x S^2 and show how their backreaction leads to the Reissner-Nordstrom black hole. This backreaction with boundary condition change is called an anabasis. I will then show that the linear Einstein equation near AdS_2 x S^2\, with or without additional matter\, enjoys an accidental symmetry that may be thought of as an on-shell large diffeomorphism of AdS_2.
URL:https://cmsa.fas.harvard.edu/event/2-24-2022-general-relativity-seminar/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
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