# 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.

## Higher-Spin Interactions: Three-point Functions and Beyond

Thursday Nov 10, 2011
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Taking String Theory as a theoretical laboratory'', I will present handy expressions for bosonic and fermionic (SUSY) higher-spin Noether currents. I will also describe a class of non-local higher-spin Lagrangian couplings that are generically required by the Noether procedure starting from four-points. The construction clarifies the origin of old problems for these systems and links String Theory to some aspects of Field Theory that go beyond its conventional low energy limit.

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## Non-Gaussianity in Single Field Inflation Beyond Slow-roll

Thursday Nov 10, 2011
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In inflationary theories, single field models are typically considered subject to slow-roll conditions. In this talk I will present current observational constraints on deviations from slow-roll, e.g. bounds coming from strong coupling considerations, scale-dependent non-Gaussianities and the tensor-to-scalar ratio. These constraints still allow significant violations of slow-roll conditions. Focusing on non-Gaussian signals, I will discuss a variety of intriguing observable signatures that can be found for fast-rolling single fields.

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## Curvature and Anisotropy Near a Nonsingular Bounce

Thursday Nov 10, 2011
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Problematic growths of curvature and anisotropy are found in nonsingular bouncing cosmologies that include both an ekpyrotic phase and a bouncing phase. Classically, initial curvature and anisotropy that are suppressed during the ekpyrotic phase will grow back exponentially during the nonsingular bouncing phase. Besides, curvature and shear perturbations are generated by quantum fluctuations during the ekpyrotic phase. In the bouncing phase, an adiabatic curvature perturbation grows to dominate and gives rise to a blue spectrum that spoils the scale-invariance.

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## Condensed Matter - Lecture 9

Thursday Nov 10, 2011
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## Quantum Field Theory II - Lecture 9

Thursday Nov 10, 2011
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## Random Matrices for Spin Decoherence

Wednesday Nov 09, 2011
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Besides their experimental relevance in condensed matter and quantum information science, quantum spin systems are an interesting playground to study decoherence and quantum entanglement. Random matrices are used since the 50' to model quantum chaotic dynamics and complex quantum systems. I introduce new random matrix models which lead to explicit solutions for some simple open or closed quantum spin systems.

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## Condensed Matter - Lecture 8

Wednesday Nov 09, 2011
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## Quantum Field Theory II - Lecture 8

Wednesday Nov 09, 2011
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## On Four Point Functions of 1/2 BPS operators in the AdS/CFT Correspondence

Tuesday Nov 08, 2011
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In this talk I will provide evidence supporting the Dolan/Nirschl/Osborn conjecture for the precise form of the amplitude of four-point functions of 1/2-BPS operators in N=4 SYM theory at strong coupling and in the large N limit. I will also discuss the methods that allowed the evaluation of amplitudes involving operators of arbitrary conformal dimension.

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## Formulating Quantum Theory as a Causally Neutral Theory of Bayesian Inference

Tuesday Nov 08, 2011
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Quantum theory can be thought of as a noncommutative generalization of Bayesian probability theory, but for the analogy to be convincing, it should be possible to describe inferences among quantum systems in a manner that is independent of the causal relationship between those systems.

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## Next Public Lecture

### EMILY LEVESQUE: THE WEIRDEST STARS IN THE UNIVERSE

Wednesday Mar 07, 2018

## RECENT PUBLIC LECTURE

### Robert Spekkens: The riddle of the quantum sphinx: quantum states and category mistakes

Speaker: Robert Spekkens