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.
The network of tests shows the LCDM cosmology is a good approximation to what actually happened, but that need not mean it has all the physics relevant to cosmology back to light element formation. I will review properties of galaxies that seem to be particularly difficult to understand within LCDM and might be pointing to still better physics.
Constraining primordial non-Gaussianity can offer a window into the early universe, and into testing the inflationary paradigm, which is fully complementary to the approach offered by Cosmic Microwave Background polarization.
Large-scale structure and galaxy surveys have recently received renewed attention as a way to constrain primordial non-Gaussianity. I will review the potential and the limitations of this approach and highlight its complementarity to Cosmic Microwave Background observations.
We describe recent progress on the quantum description of the Kerr black hole. Previous descriptions of black hole microstates have relied on the existence of near-horizon regions with conformal symmetry, and hence have only worked for extremal or supersymmetric black holes. We argue that the states of non-extremal black holes can also be understood in terms of a conformal symmetry, the difference being that this symmetry is not geometrically realized. Thus a Kerr black hole is an excited state of a conformal field theory.
I will discuss a recent proposal to regulate the infinities of eternal inflation by relating a late-time cutoff in the bulk to a short-distance cutoff on the conformal boundary of the spacetime.
It has been suggested, by Kallosh and Linde, that a generic bound on inflation in string theory keeps the
I will describe recent work by Cutler&Holz and Hirata, Holz, & Cutler showing that a highly sensitive, deci-Hz gravitational-wave mission like BBO or Decigo could measure cosmological parameters, such as the Hubble constant H_0 and the dark energy parameters w_0 and w_a, far more accurately than other proposed dark-energy missions.
Magnetic fields are ubiquitous in our Universe. The are observed in galaxies and clusters in our vicinity and at high redshifts.