Since 2002 Perimeter Institute has been recording seminars, conference talks, public outreach events such as talks from top scientists 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 and 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.
Accessibly by anyone with internet, Perimeter aims to share the power and wonder of science with this free library.
We analyze the
implications for Susy theories of a Higgs to di-photon rate enhanced, if
compared to the Standard Model prediction. We show how models predicting a
sizable enhancement have generically an electroweak vacuum that is not
absolutely stable. In particular we discuss the only viable scenario that can
predict sizable new physics effects in the di-photon rate in the framework of
the MSSM: a scenario with light and heavily mixed staus. We conclude with the
Cosmological
birefringence is a postulated rotation of the linear polarization of photons
that arises due to a Chern-Simons coupling of a new scalar field to
electromagnetism. In particular, it appears as a generic feature of simple
quintessence models for Dark Energy, and therefore, should it be detected,
could provide insight into the microphysics of cosmic acceleration. Prior work
has sought this rotation, assuming the rotation angle to be uniform across the
sky, by looking for the parity-violating TB and EB correlations in the CMB
A "one-time program" for a channel C is a
hypothetical cryptographic primitive by which a user may evaluate C on only one
input state of her choice. (Think Mission Impossible: "this tape
will self-destruct in five seconds.") One-time programs cannot be
achieved without extra assumptions such as secure hardware; it is known that
one-time programs can be constructed for classical channels using a very basic
hypothetical hardware device called a "one-time memory".
I will recall the
main motivations for considering spin foam models in their Group Field Theory
(GFT) versions, which are quantum field theories defined on group manifolds. As
for any other quantum field theory, a fully consistent definition of the latter
must involve renormalization. I will briefly review a specific class of GFTs,
called tensorial, for which progress in this direction has recently been possible.
A new just-renormalizable model, in three dimensions and on the SU(2) group,
Pulsars are rotating magnetized neutron stars that emit
broadband pulses of radiation. Our ability to model magnetospheres of pulsars has been hampered by the difficulty of solving the self-consistent behavior of strongly magnetized relativistic plasmas. I will describe
recent progress in numerical modeling of magnetically-dominated plasmas and show applications to pulsar magnetospheres in increasing levels of realism, including ideal and resistive force-free,
The information paradox and the infall problem have been
long-standing puzzles in the understanding of black holes. The idea of free
infall is in considerable tension with unitarity of the evaporation process and
recent developements have made this tension sharp. In the first part of my talk
I will address the information question and argue that unitarty requires every
quantum of radiation leaving the black hole to carry information about the
initial state. Unitary evaporation is thus inconsistent with an
Curiosity is often said to drive science, but until the seventeenth century – the age of
the so-called Scientific Revolution – it was regarded with suspicion and
condemnation. What happened to liberate curiosity? Why did no question seem too
vast or trivial to be ruled out of bounds? And what does the freedom to be
curious really mean for science today?
We study the robustness of quantum information stored in
the degenerate ground space of a local, frustration-free Hamiltonian with
commuting terms on a 2D spin lattice. On one hand, a macroscopic energy barrier
separating the distinct ground states under local transformations would protect
the information from thermal fluctuations. On the other hand, local topological
order would shield the ground space from static perturbations.
Warped AdS3 has isometry SL(2,R) x U(1). It is closed
related to Kerr/CFT, non local dipole theories and AdS/CMT. In this talk I will
derive the spectrum of string theory on
Warped AdS3. This is possible because the worldsheet theory can be
mapped to the worldsheet on AdS3 by a nonlocal field redefinition.
Check back for details on the next lecture in Perimeter's Public Lectures Series