Video Library

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. 

  

 

Wednesday Apr 06, 2016
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Bott periodicity (1956) is a classical and old result in mathematics.

Its easiest incarnation of which concerns Clifford algebras. It says

that, up to Morita equivalence, the real Clifford algebras Cl_1(R),

Cl_2(R), Cl_3(R), etc. repeat with period 8. A similar result holds

for complex Clifford algebras, where the period is now 2. The modern

way of phrasing Bott periodicity in is terms of K-theory: I will

explain how one computes K-theory, and we will see the 8-fold Bott

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Tuesday Apr 05, 2016

Recent work suggests that a sharp definition of `phase of matter' can be given for some quantum systems out of equilibrium---first for many-body localized systems with time independent Hamiltonians and more recently for periodically driven or Floquet localized systems. We present a new family of driven localized Floquet phases, which are analogues of the 1d symmetry protected topological phases familiar from the equilibrium setting. We then propose a classification for such phases.

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Tuesday Apr 05, 2016
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In the de Broglie-Bohm pilot-wave formulation of quantum theory, standard quantum probabilities arise spontaneously through a process of dynamical relaxation that is broadly similar to thermal relaxation in classical physics. If we are to regard this process as the cause of the quantum probabilities we observe today, then we must infer a primordial ‘quantum nonequilibrium’ in the remote past.

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Tuesday Apr 05, 2016
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Tuesday Apr 05, 2016
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Tuesday Apr 05, 2016
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I will explain how to axiomatize the notion of a chiral WZW model using the formalism of VOAs (vertex operator algebras). This class of models is in almost bijective correspondence with pairs (G,k), where G is a connected (not necessarily simply connected) Lie group and k in H^4(BG,Z) is a degree four cohomology class subject to a certain positivity condition. To my surprise, I have found a couple extra models which satisfy all the defining properties of chiral WZW models, but which don't come from pairs (G,k) as above.

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