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.
will describe a discrete model of spacetime which is quantum-mechanical,
causal, and background free. The kinematics is described by networks whose
vertices are labelled with arrows. These networks can be evolved forwards (or
backwards) in time by using unitary replacement rules. The arrow structure
permits one to define dynamics without using an absolute time parameter.
Based on arXiv:1201.2489.
Already the last decade has
witnessed unprecedented progress in the collection of cosmological data.
Presently proposed and designed future cosmological probes and surveys permit
us to anticipate the upcoming avalanche of cosmological information during the
The increase of valuable observations needs to be accompanied with the development
of efficient and accurate information processing technology in order to analyse
and interpret this data. In particular, cosmography projects, aiming at studying
this talk, I will construct a symmetry protected topological phase of bosons in
3d with particle number conservation and time reversal symmetries, which is the
direct bosonic analogue of the familiar electron topological insulator. The
construction employs a parton decomposition of bosons, followed by condensation
of parton-monopole composites. The surface of the resulting state supports a
gapped symmetry respecting phase with intrinsic toric code topological order
where both e and m anyons carry charge 1=2.