Along with a brief introduction to the phenomenon of the integer quantum Hall effect, I will briefly review edge reconstruction due to Coulomb interactions and changes in the smoothness of the edge potential. Then I will describe some recent work where we show how exchange interactions can cause a switching of the spin of the edge modes, causing like spins to come close to each other.
05/12/2017 at 10:30 am
Prof. M. P. Das, Department of Theoretical Physics, The Australian National University
Einstein had an enigmatic ability to arrive at powerful conclusions using a few well-known assumptions. Explanation of the Photoelectric effect is a bright example of that. In this talk we retrospect the so-called quantum revolution beginning with the photoelectric phenomenon. Following this historical endeavor, we present post-Einstein development of theories and experiments on photoemission from solids.
29/11/2017 at 4:00 pm
Professor Rajiv V. Gavai, TIFR, Mumbai
Colloquium
IOP Lecture Hall
Document Date:
Exciting Odyssey in the Femto-world: QCD Critical Point
Non-BPS D1-D5-P solutions and Gravitational Instantons
Abstract
Extremal Black hole microstate geometries have been well studied in the context of the black hole information puzzle and the fuzzball proposal. Non-extremal black hole microstates are much more interesting but less explored. Using the AdS/CFT prescription, we identify a general class of dual states of non-supersymmetric orbifolded D1-D5-P supergravity solutions (JMaRT). We compute the massless scalar emission spectrum and emission rate both in the gravity and CFT sides and show that they match perfectly, thus providing strong evidence for our identification. We also study pair creation like picture from the ergoregion of these geometries. We further present novel approaches to construct these solutions systematically using group theory techniques. Higher dimensional gravity theories when dimensionally reduced to two dimensions manifest infinite number of symmetries. The infinite dimensional symmetry group is known as the Geroch group. We construct Geroch group SL(3,R) matrices for the 5D Myers-Perry and Kaluza-Klein black holes. Moreover we construct the non-BPS D1-D5-P JMaRT solution using inverse scattering method followed by group theory techniques. We show that these solutions can be thought of as charged Euclidean 5D Myers-Perry instanton.
