Department Colloquia
Spring 2019 Schedule
All talks will be in the Physics Department Library (accessed from 3438 Ingersoll Hall) unless otherwise stated.
Check here for updates to the schedule as the semester progresses.
Wednesday, March 13, 12:30 p.m.
Speaker: Anatoly Kuklov, Department of Physics & Astronomy, College of Staten Island (CUNY) and The Graduate Center (CUNY)
Title: Superfluidity beyond Helium-4
Abstract: The remarkable phenomena of Bose-Einstein condensation and superfluidity were first observed in liquid Helium-4 about 80 years ago. Then, at the end of 20th century, these effects were realized in ultra cold clouds of atoms Rb-87, Na-23 and Li-7. Similar effects were also observed in exciton-polariton media. I will argue that the condensation of pure light in 2D geometry produced by the photonic group in Bonn University 9 years ago provides a new platform for studying novel phases and phase transitions some of which have no analogy in other systems. The combination of low effective mass of the confined light and the presence of the dye molecules with randomly oriented dipolar transition engages a competition between disorder and the tendency to forming algebraic off-diagonal order. The phase diagram of possible phases is constructed at the mean field level. One of such novel phases is the condensate of photon pairs induced solely by the orientational disorder.
Date TBC:
Speaker: Matthew O'Dowd, Lehman College (CUNY) and The Graduate Center (CUNY)
Title: The Heart of the Quasar
Abstract: Quasars provide one of the few observable manifestations of the extreme behavior of matter near black holes and they are an important factor in the energetic evolution of the Universe. Yet due to their vast distances and compact sizes, we have only a crude understand the physics behind their powerful emission processes. I will discuss an extremely promising technique to map the inner structure of quasars through gravitational microlensing. This technique takes advantage of size-dependent magnification fluctuations in multiply-imaged quasars that result from the gravitational substructure of the intervening lensing galaxy. With our new Hubble Space Telescope observations we apply this technique to make the most reliable-to-date measurement of quasar accretion disk temperature gradients.
More Information
Direct any enquiries to Karl Sandeman.
