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.
I review the best-matching construction, and the striking properties of a Jacobi-type action first introduced by Baierelein, Sharp and Wheeler. The simplest theories compatible with such an action principle must have a universal light-cone and gauge symmetry. I also describe the implementation of three-dimensional conformal symmetries on the basis of the BSW action, which gives a first-principles derivation of York's solution of the initial value problem in General Relativity.
Shape Dynamics first arose as a theory of particle interactions formulated without any of Newton's absolute structures. Its fundamental arena is shape space, which is obtained by quotienting Newton's kinematic framework with respect to translations, rotations and dilatations. This leads to a universe defined purely intrinsically in relational terms. It is then postulated that a dynamical history is determined by the specification in shape space of an initial shape and an associated rate of change of shape. There is a very natural way to create a theory that meets such a requirement.
Shape Dynamics first arose as a theory of particle interactions formulated without any of Newton's absolute structures. Its fundamental arena is shape space, which is obtained by quotienting Newton's kinematic framework with respect to translations, rotations and dilatations. This leads to a universe defined purely intrinsically in relational terms. It is then postulated that a dynamical history is determined by the specification in shape space of an initial shape and an associated rate of change of shape. There is a very natural way to create a theory that meets such a requirement.
The tremendous empirical success of Einstein's relativity has pushed Aether into a chapter in the history books, for nearly a century. However, a phenomenologically consistent quantum mechanical treatment of gravity has motivated a revival of aether, by taming its UV-divergences, or the cosmological constant problem. Here I will outline the phenomenological implications of a physically motivated aether model. I will also discuss how aether could potentially evade traditional tests of Lorentz violation, through strong coupling.
This talk reviews the idea of quantum gravity with anisotropic scaling, and presents a scenario in which this theory of gravity is coupled to matter, described by the standard model or beyond.This "multicritical universe" scenario predicts systematic, energy-dependent, calculable Lorentz-violating corrections to the relativistic dispersion relations of matter.
TBA
The distinction between a realist interpretation of quantum theory that is psi-ontic and one that is psi-epistemic is whether or not a difference in the quantum state necessarily implies a difference in the underlying ontic state. Psi-ontologists believe that it does, psi-epistemicists that it does not. This talk will address the question of whether the PBR theorem should be interpreted as lending evidence against the psi-epistemic research program.
It is well known that on-shell recursion relation can be applied to tree-level amplitude in string theory. One technical issue of the application is the sum of infinite middle on-shell states. We discuss how we can do the sum exactly to reproduce the known result.
With the emergence of the dark sector in cosmology, a variety of modified theories of gravity have come to the fore. I will discuss a framework which can be used to test gravity on large scales and the observational programmes that might lead to the tightest constraints.
In this talk I will review recent results we obtained regarding the computation of Wilson loops in the context of the AdS/CFT correspondence. According to such correspondence Wilson loops are related to minimal area surfaces in hyperbolic space. The problem reduces to solving a set of non-linear but integrable differential equations. The solutions can be expressed in terms of Riemann theta functions. Other methods such as the dressing method applied to this problem will also be discussed.
Check back for details on the next lecture in Perimeter's Public Lectures Series