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.
After the seminal work of Connes and Tretkoff on the Gauss-Bonnet theorem for the noncommutative 2-torus and its extension by Fathizadeh and myself, there have been significant developments in understanding the local differential geometry of these noncommutative spaces equipped with curved metrics. In this talk, I will review a series of joint works with Farzad Fathizadeh in which we compute the scalar curvature for curved noncommutative tori and prove the analogue of Weyl's law and Connes' trace theorem.
The same bulk two-dimensional topological phase can have multiple distinct, fully-chiral edge phases. We show that this can occur in the integer quantum Hall states at fillings 8 and 12 with experimentally-testable consequences. We also show examples for Abelian fractional quantum Hall states, the simplest examples being at filling fractions 8/7, 12/11, 8/15, 16/5. For all examples, we propose experiments that can distinguish distinct edge phases. Our results are summarized by the observation that edge phases correspond to lattices while bulk phases correspond to genera of lattices.
We study the classical constraint algebra of Hořava-Lifshitz gravity, where due to the breaking of 4d diffeomorphism symmetry, there is a new dimensionless coupling absent in GR and whose role is not yet clear. Starting from two apparently contradictory results, we show how the role of the extra coupling differs between the projectable and non-projectable versions of the theory. In particular, we see how in the latter, it gives rise to a non-trivial constraint algebra, akin to the conditions seen in the CMC gauge of GR.
Our current definition of what a black hole is relies heavily on the assumption that there exists a finite maximum speed of propagation for any signal. Indeed, one is tempted to think that the notion of a black hole has no place in a world with infinitely fast signal propagation. I will use concrete examples from Lorentz-violating gravity theories to demonstrate that this naive expectation is not necessarily true.
There has been considerable interest in determining whether the universality hypothesis extends to systems which are of non-integer dimension or to systems which are scale invariant (fractals). Specifically research into these types of systems is concerned with determining the relevance of topological properties to their critical phenomena. We have performed Monte Carlo simulations for the XY model on three fractal lattices with different topological properties: the Sierpinski pyramid Menger sponge and Sierpinski carpet.
Turbulence is ubiquitous in hydrodynamics and its study is dominated by statistical methods and dimensional arguments. Even so analytic results tend to rely heavily on statistical symmetries. I will discuss some such results in non-relativistic turbulence and possible extensions to the relativistic case. The 2+1 dimensionality of our numerical setup allows for gaining insight about 3+1 gravity through the fluid/gravity duality. This work aims to further our understanding of the fluid side in its own right.
By numerically solving Einstein equations we are able to study the strong regime of gravity. In many astrophysical scenarios strong gravity plays a fundamental role such as compact binary systems: e.g. Black Hole binaries binary Neutron Stars and Black Hole-Neutron Star systems. In this talk I will discuss the simulations our group has been conducting in binary Neutron Star system where we can study the dynamics and gravitational radiation of the systems but also establish important connections with electromagnetic counterparts and even testing alternatives theories of gravity (i.e.
This work has been published:Viner C Dorman SN Shirley BC and Rogan PK (2014)Validation of predicted mRNA splicing mutations using high-throughput transcriptome data [v1; ref status: indexedhttp://f1000r.es/2no]F1000Research20143:8 (doi:10.12688/f1000research.3-8.v1)Additionally this work has been accepted for a highlights presentation at the upcoming Great Lakes Bioinformatics Conference (GLBIO) in Cincinnati Ohio and it was recently presented as a poster at London Health Research Day (LHRD).Abstract:Interpretation of variants present in complete genomes or exomes reveals numerous s