Since 2002 Perimeter Institute has been recording seminars, conference talks, and public outreach events using video cameras installed in our lecture theatres. Perimeter now has 7 formal presentation spaces for its many scientific conferences, seminars, workshops and educational outreach activities, all with advanced audio-visual technical capabilities. Recordings of events in these areas are all available On-Demand from this Video Library and on Perimeter Institute Recorded Seminar Archive (PIRSA). PIRSA is a permanent, free, searchable, and citable archive of recorded seminars from relevant bodies in physics. This resource has been partially modelled after Cornell University's arXiv.org.
We describe a new correspondence between four-dimensional conformal field theories with extended supersymmetry and two-dimensional chiral algebras. We explore the resulting chiral algebras in the context of theories of class S. The class S duality web implies nontrivial associativity properties for the corresponding chiral algebras, the structure of which can be summarized by a generalized topological quantum field theory.
Dark matter is clear evidence of the existence of new physics beyond the Standard Model, and there are compelling reasons to expect that this physics can be probed at the LHC. As we prepare for Run II, we must consider a wide range of possible phenomenology, leaving no stone unturned. In this talk, I present a set of scalar and pseudoscalar models which provide a useful framework to interpret dark matter results, and can motivate new searches in novel channels at the LHC.
Peculiar velocities - deviations from Hubble expansion - are the only practical probe of the growth of matter density fluctuations on very large scales in the nearby Universe. I will discuss recent measurements of quantities of cosmological interest from our group and others. One is the "bulk" flow of nearby galaxies with respect to the frame defined by the Cosmic Microwave Background, and what this tells us about fluctuations on large very spatial scales.
At large N, an important sector of the ABJM field theory defined on a stack of N M2-branes can be described holographically by the D=4 N=8 SO(8)-gauged supergravity of de Wit and Nicolai. Since its inception, the latter has been tacitly assumed to be unique. Recently, however, a one-parameter family of SO(8) gaugings of N=8 supergravity has been discovered, the de Wit-Nicolai theory being just a member in this class. I will explain how this overlooked family of SO(8)-gauged supergravities is deeply related to electric/magnetic duality breaking in four dimensions.