The microscopic description of black holes has been a challenge for more that forty years.  There are now quite a number of promising approaches to solving this problem and the primary goal of this conference and workshop is to bring together experts in these areas to identify synergies, engage in constructive criticism and resolve apparent conflicts.  A significant focus will be the dynamics of black-hole microstructure: how infalling matter is scrambled and how information is recovered.

The conference will involve three or four talks a day and three panel discussions.   All events will be held via Zoom and streamed to Youtube
Organizers: Iosif Bena and Nick Warner

https://indico.in2p3.fr/event/24137/

Thermalization and out of equilibrium dynamics of many body strongly interacting quantum systems have been the subject of a recent burst of research activities. In particular the dynamics of operator and information spreading (scrambling) as well as its chaotic behavior have been recently investigated starting from models originated in the context of strongly correlated many body systems and have found application to black holes physics. This has been triggered by the appearance of a new class of exactly soluble large N quantum field theories, such as the celebrated Sachdev-Ye-Kitaev model. The aim of this workshop is to review the recent advances in the field and to stimulate further research in this direction which lies at the interface between statistical and condensed matter physics and high-energy/mathematical physics.

Due to the current situation, the conference will take place online.

Organizing committee: Monica Guica, Marco Schirò, Pierfrancesco Urbani, Laure Sauboy (Secretary)

Registration: here

http://indico.in2p3.fr/event/20611/

CC BY 3.0 (as fig. 1 from  Event Horizon TelescopeCollaboration, K. Akiyama et al., First M87 Event Horizon Telescope Results. V. Physical Origin of the Asymmetric Ring, Astrophys.J. Lett.875(2019), no. 1, L5,1906.11242 )

More than a century after their theoretical discovery, black holes still hold many mysteries. We have developed new methods to calculate an infinite number of hitherto unknown parameters of any arbitrary black hole, some of which we believe could be observed in current and future experiments.

Half of these multipoles are finite, and the other half vanish.  Any ratio of two vanishing moments thus seems to be ill-defined. By embedding black holes in string theory, we develop a novel method to define and calculate such multipole moment ratios unambiguously for any black hole. In this way, we find an infinite number of previously unknown multipole ratios for any Kerr black hole.

Our method can also be used to calculate multipole ratios for supersymmetric black holes. There exist a large number of horizonless geometries that have the same charges as these supersymmetric black holes and only differ from them close to the horizon. We also develop an independent second method to calculate multipole ratios using these “microstate geometries,” and find striking similarities between the results of the two methods.

Contact: Iosif Bena

https://journals.aps.org/prl/abstract/10 ...