# 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.

## Fine Tuning May Not Be Enough

Tuesday Aug 11, 2015
Speaker(s):

This talk is based on arXiv:1506.07306, with Shun-Pei Miao. We argue that the fine tuning problems of scalar-driven inflation may be worse than is commonly believed. The reason is that reheating requires the inflaton to be coupled to other matter fields whose vacuum fluctuations alter the inflaton potential. The usual response has been that even more fine-tuning of the classical potential $V(\varphi)$ can repair any damage done in this way.

Scientific Areas:

## Welcome Speech - Neil Turok

Tuesday Aug 11, 2015

## Funny Thing Happened on the Way to Convergence.

Monday Aug 10, 2015
Speaker(s):

Modeling the cosmic velocity field, and especially estimating its lowest order moment, the bulk flow, has been a popular pursuit among aficionados in the cosmological community for three decades now. Other than estimating the magnitude and direction of the flow, one of the main difficulties has been defining the scale of flow detected. There is a nearly universal agreement as to the direction of the flow, however, there is some disagreements regarding the magnitude and scale of the flow.

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## CMB Anomalies and Non-Gaussianity

Monday Aug 10, 2015
Speaker(s):

When the primordial fluctuations are non-Gaussian and inflation lasts longer than the minimum number of e-folds, the likelihood that we observe mild deviations from isotropy increases. I will present a single framework that encompasses many of the most promising scenarios for generating a hemispherical power asymmetry. This framework allows a comparison of the observational evidence for various models, including some with a natural connection between large scale power suppression and power asymmetry.

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## Precision reconstruction of the cold dark matter-neutrino relative velocity.

Monday Aug 10, 2015
Speaker(s):

Neutrinos occur in great number throughout the Universe, yet remain poorly understood due to their weak interactions with other matter. In particular, individual neutrino masses remain an elusive property for particle physicists and cosmologists abound. Recently, it has been proposed that individual neutrino masses may be constrained from observations of neutrino wakes that result from the relative flow between cold dark matter (CDM) and neutrinos. The only required knowledge for such a detection is the relative velocity field between CDM and neutrinos.

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## TianNu: simulating the neutrino sky

Monday Aug 10, 2015
Speaker(s):

TBA

Scientific Areas:

## Probing cosmic flows through the kinematic Sunyaev Zel'dovich effect

Monday Aug 10, 2015

Beyond its primary fluctuations, the cosmic microwave background (CMB) contains a wealth of information on the large-scale structure of the universe, which it illuminates as a backlight. The baryon momentum field is thus imprinted on the CMB through the kinematic Sunyaev-Zel'dovich (kSZ) effect. Current small-scale high-sensitivity CMB experiments make this effect detectable, providing a unique handle on peculiar velocities and baryon physics.

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## TBA

Monday Aug 10, 2015

TBA

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## PSI 2015/2016 Welcome/Orientation

Monday Aug 10, 2015

9:30 am - Neil Turok, Director, Perimeter Institute

10:30 am - Jennifer Yuen, Counselling Services, UW

11:00 am - Michael Duschenes, Managing Director and Chief Operating Officer

11:20 am - Break

11:30 am - Sheri Keffer and Patti Butler, People and Culture

11:45 am - Dan Lynch, Bistro

12:00 pm - Dawn Bombay, Library

## Structure formation with hot particles

Monday Aug 10, 2015
Speaker(s):

I will describe a novel method for simulating nonlinear structure formation in cosmologies that have hot or warm collisionless species. After introducing the method, I will show results of our simulations for universes with massive neutrinos, and warm dark matter simulations.

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## Next Public Lecture

Check back for details on the next lecture in Perimeter's Public Lectures Series

## RECENT PUBLIC LECTURE

### Niels Bohr: Life Behind the Physics

Speaker: Vilhelm Bohr