# 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.

## The quantum origin of the cosmological structure: an arena for quantum gravity phenomenology

Monday Nov 05, 2007
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I will review the shortcomings of the standard account of the origin of anisotropies and in-homogeneities in inflationary cosmology. I will argue that something beyond the established paradigm of physics in needed for a satisfactory explanation of the process by which the seeds of structure emerge from the inflaton vacuum and will consider the application of a generalization of the ideas of R Penrose about a quantum gravity induced dynamical collapse of the quantum mechanical state of a system as a promising avenue to address the issue.

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## Inflation with a Cutoff: Proposals and Problems

Monday Nov 05, 2007
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The possible existence of a physical UV cutoff in dynamical spacetimes raises a number of conceptual and practical questions. If the validity of Lorentz Invariance is considered unreliable above the cutoff, the creation or destruction of quantum modes and the choice of their initial state need to be described explicitly. It has been proposed that these trans-Planckian effects might leave an oscillatory imprint on the power spectrum of inflationary perturbations. However, taking into account the fluctuations of the cutoff, the signal is smeared out beyond recognition.

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## Planck Meets Hubble and Boltzmann: Holographic Quantum Foam and Cosmology

Monday Nov 05, 2007
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Quantum fluctuations of spacetime give rise to quantum foam, and black hole physics dictates that the foam is of holographic type. One way to detect quantum foam is to exploit the fact that an electromagnetic wavefront will acquire uncertainties in direction as well as phase as it propagates through spacetime. These uncertainties can show up in interferometric observations of distant quasars as a decreased fringe visibility.

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## Z\' mediation of supersymmetry breaking

Monday Nov 05, 2007
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If some form of string theory indeed describes the ultra high energy physics of our universe, then there are two ingredients which are very likely to remain at low energies. The first, is a fifth force in the form of an additional abelian gauge group. The second, and more dramatic, is supersymmetry. Both may be observed at the upcoming Large Hadron Collider. In this talk I will explore a possible intimate connection between these two ingredients which leads to surprising predictions.

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## Quantum-Gravity-induced Decoherence and intrinsic CPT Violation: towards smoking-gun experimental evidence in entangled particle states?

Monday Nov 05, 2007
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Quantum Gravity may be entirely unconventional as a theory, leading to completely unfamiliar (compared to other fields of physics) and unexpected experimental signatures. One particularly interesting avenue for research in that field is the study of models in which quantum gravity operates as a decoherening foamy space-time medium\'\', with which ordinary propagating matter interacts.

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## Intro to Supersymmetry 14

Thursday Nov 01, 2007
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## Spontaneous Broken Symmetry 1

Thursday Nov 01, 2007
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## Estimating Jones polynomials is a complete problem for one clean qubit.

Wednesday Oct 31, 2007
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The one clean qubit model is a model of quantum computation in which all but one qubit starts in the maximally mixed state. One clean qubit computers are believed to be strictly weaker than standard quantum computers, but still capable of solving some classically intractable problems. I\'ll discuss my recent work in collaboration with Peter Shor which shows that evaluating a certain approximation to the Jones polynomial at a fifth root of unity for the trace closure of a braid is a complete problem for the one clean qubit complexity class.

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## d=3 SIC POVMs and Elliptic Curves

Tuesday Oct 30, 2007
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The simplest algebraic curves of genus one are the nonsingular cubics in two-dimensional complex projective space. Interpreting CP^2 as the space of pure quantum states associated with a Hilbert space of dimension three, I will show how various properties of d=3 symmetric informationally complete positive operator valued measures can be understood in terms of the geometry of such curves. The resulting structure, although of considerable complexity, is very beautiful from a mathematical perspective.

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## Constraints on scale dependent non-Gaussianity

Tuesday Oct 30, 2007
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The detection of primordial non-Gaussianity could provide a powerful means to rule out various inflationary scenarios. Although scale-invariant non-Gaussianity is currently best constrained by the Cosmic Microwave Background, single-field inflation models with changing sound speed can have strongly scale dependent non-Gaussianity. I will discuss the theoretical motivation for such models and present work on the likely ability of current and future large scale structure measurements to constrain them.

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## Next Public Lecture

### INGRID WALDRON, DALHOUSIE UNIVERSITY

Tuesday Apr 24, 2018

## RECENT PUBLIC LECTURE

### Rob Moore: Stanford Institute for Materials and Energy Sciences

Speaker: Rob Moore