Colloquium

Displaying 385 - 396 of 609

What is motion? What is time?

Flavio Mercati University of Naples Federico II
January 23, 2013

PIRSA:13010003
Quantum Gravity
Einstein's gravity versus String Gravity

Barton Zwiebach Massachusetts Institute of Technology (MIT) - Department of Physics
January 16, 2013

PIRSA:13010103
Quantum Fields and Strings
Adventures with Monte Carlo Simulations of the Self-Avoiding Walk

Esaias Janse van Rensburg York University

December 12, 2012

PIRSA:12120025
Wiring up Quantum Systems: Fun with Artificial Atoms and Microwave Photons

Steve Girvin Yale University
November 28, 2012

PIRSA:12110041
Condensed Matter
Quantum Signatures of Chaos

Shohini Ghose Wilfrid Laurier University

November 21, 2012

PIRSA:12110072
Massive gravitons, the cosmological constant and new directions in gravity
November 14, 2012

PIRSA:12110061
Cosmology
An introduction to quantum channels and their capacities

Graeme Smith Institute for Quantum Computing (IQC)
November 07, 2012

PIRSA:12110066
Quantum Information
Astrophysical shear-driven turbulence

Jeremy Goodman Princeton University

October 17, 2012

PIRSA:12100043
Warm Superconductors

Baskaran Ganapathy Institute of Mathematical Sciences

October 10, 2012

PIRSA:12100059
New Observations about the Renormalization Group Flow

Zohar Komargodski Stony Brook University
September 26, 2012

PIRSA:12090058
Quantum Fields and Strings
The Higgs Boson and speculative particle physics

Mark Wise California Institute of Technology (Caltech)

September 19, 2012

PIRSA:12090065
A Journalist's Perspective on Science Media

Ivan Semeniuk The Globe and Mail

June 20, 2012

PIRSA:12060017

What is motion? What is time?

Flavio Mercati University of Naples Federico II
January 23, 2013

PIRSA:13010003
Quantum Gravity
I give an account of the Machian approach to dynamics, from Mach's critique of Newton to the work of Barbour, Bertotti, York and O'Murchadha, which culminated in the theory of Shape Dynamics, a new and original way of thinking about General Relativity. I conclude commenting on the present research lines in Shape Dynamics, and the opportunity it offers to solve the problem of time in quantum gravity.

Support for this colloquium is provided by The Templeton Frontiers Program.
Einstein's gravity versus String Gravity

Barton Zwiebach Massachusetts Institute of Technology (MIT) - Department of Physics
January 16, 2013

PIRSA:13010103
Quantum Fields and Strings
Gravity in string theory is a generalized version of Einstein's theory with some universal features that call for a reformulation of the key geometrical concepts. In addition to the metric tensor, for example, string theory contains an antisymmetric tensor and a dilaton that allow for extra symmetries. A new branch of mathematics, Generalized Geometry, suggests a framework that finds a realization in the recent Double Field Theory formulation of string gravity. I will describe the main ideas, the progress, and the mysteries that remain in the search for a proper description of string gravitation.
Adventures with Monte Carlo Simulations of the Self-Avoiding Walk

Esaias Janse van Rensburg York University

December 12, 2012

PIRSA:12120025

The Rosenbluth Method is a classical kinetic growth Monte Carlo algorithm for growing a self-avoiding walk by appending steps to its endpoint. This algorithm can be generalised by the implementation of more general elementary moves (for example, BFACF elementary moves) to realise kinetic growth algorithms for lattice polygons. This generalises the counting principle that underlies the Rosenbluth method and the result is a widely applicable class of algorithms which may be used for microcanonical sampling in discrete models. In addition to self-avoiding walks, several applications of kinetic growth and canonical Monte Carlo algorithms will be presented, including the sampling of trivial words in abstract groups, as well as knotted lattice polygons and discrete lattice spin systems such as the Potts model. This is work was done in collaboration with Andrew Rechnitzer of the Mathematics Department at the University of British Columbia.
Wiring up Quantum Systems: Fun with Artificial Atoms and Microwave Photons

Steve Girvin Yale University
November 28, 2012

PIRSA:12110041
Condensed Matter
A revolution is underway in the construction of ‘artificial atoms’ out of superconducting electrical circuits. These macroscopic ‘atoms’ have quantized energy levels and can emit and absorb quanta of light (in this case microwave photons), just like ordinary atoms. Unlike ‘real’ atoms, the properties of these artificial atoms can be engineered to suit various particular applications, and they can be connected together by wires to form quantum ‘computer chips.’ This so-called ‘circuit QED’ architecture has given us the ability to do non-linear quantum optics in electrical circuits at the single photon level. It is now possible to entangle multiple qubits, count individual microwave photons, create large ‘Schrödinger cat’ photon states and perform quantum feedback. This talk will present an elementary introduction to the field.
Quantum Signatures of Chaos

Shohini Ghose Wilfrid Laurier University

November 21, 2012

PIRSA:12110072
Massive gravitons, the cosmological constant and new directions in gravity
November 14, 2012

PIRSA:12110061
Cosmology
The solutions to the cosmological constant problems may involve modifying the very long-range dynamics of gravity by adding new degrees of freedom. As an example of a conservative and minimal such modification, we consider the possibility that the graviton has a very small mass. Massive gravity has received renewed interest due to recent advances which have resolved its traditional problems. This kind of modification has some peculiar and unexpected features, and it points us towards a universe which looks quite unfamiliar.
Support for this colloquium is provided by The Templeton Frontiers Program.
An introduction to quantum channels and their capacities

Graeme Smith Institute for Quantum Computing (IQC)
November 07, 2012

PIRSA:12110066
Quantum Information
A quantum communication channel can be put to many uses: it can transmit classical information, private classical information, or quantum information. It can be used alone, with shared entanglement, or together with other channels. For each of these settings there is a capacity that quantifies a channel's fundamental potential for communication. In this introductory talk, I will discuss what we known about the various capacities of a quantum channel, including a discussion of synergies between different channels and related additivity questions.
Astrophysical shear-driven turbulence

Jeremy Goodman Princeton University

October 17, 2012

PIRSA:12100043

Astronomical hydrodynamics is usually almost ideal in the sense that the Reynolds number (Re) is enormous and any effective viscosity must be due to shocks or turbulence. Astronomical magnetohydrodynamics (MHD) is often also nearly ideal, so that magnetic fields and plasma are well coupled. In particular, dissipation of orbital energy in accretion disks around black holes is readily explained by MHD turbulence. On the other hand, the planet-bearing disks around protostars are magnetically far from ideal because of very low fractional ionization. MHD turbulence is at best marginal in these disks, yet accretion is observed. The Reynolds numbers based on orbital-velocity gradients are enormous, so by analogy with high-Re terrestrial flows, one might expect hydrodynamic (i.e., unmagnetized) turbulence. Direct numerical simulations indicate that such turbulence is somehow suppressed by keplerian rotation, though the mechanism is
unclear and the simulations are limited in Re. Recently, a few groups have studied the question via Taylor-Couette experiments at somewhat higher Re, obtaining conflicting results. Complicating and enriching this debate is the recent discovery that turbulence tends to have a finite lifetime in shear flows that admit a formally linearly stable laminar solution: this includes flow in smooth pipes and probably also unmagnetized keplerian disks. Some suggestions will be offered as to how these open questions might be resolved.
Warm Superconductors

Baskaran Ganapathy Institute of Mathematical Sciences

October 10, 2012

PIRSA:12100059
New Observations about the Renormalization Group Flow

Zohar Komargodski Stony Brook University
September 26, 2012

PIRSA:12090058
Quantum Fields and Strings
We review recent breakthroughs in understanding some general features of the Renormalization Group and of Quantum Field Theory. We discuss some applications of these new results and their deep connection to the entanglement of the Quantum Field Theory vacuum.
The Higgs Boson and speculative particle physics

Mark Wise California Institute of Technology (Caltech)

September 19, 2012

PIRSA:12090065

The crucial role that the Higgs boson plays in the standard model for strong weak and electromagnetic interactions is reviewed. Recently a resonance with properties consistent with those expected for the Higgs boson has been discovered at the large hadron collider (LHC). This discovery constrains speculations about new physics beyond what is in the standard model. The motivation for such new physics, at roughly the energy scale probed by LHC experiments, and the nature of the constraints imposed by the recent LHC results are discussed.
A Journalist's Perspective on Science Media

Ivan Semeniuk The Globe and Mail

June 20, 2012

PIRSA:12060017

TBA

Title	Speaker(s)	Date	Talk Type	Info
What is motion? What is time?	Flavio Mercati	2013-01-23	Scientific Series	View details
Einstein's gravity versus String Gravity	Barton Zwiebach	2013-01-16	Scientific Series	View details
Adventures with Monte Carlo Simulations of the Self-Avoiding Walk	Esaias Janse van Rensburg	2012-12-12	Scientific Series	View details
Wiring up Quantum Systems: Fun with Artificial Atoms and Microwave Photons	Steve Girvin	2012-11-28	Scientific Series	View details
Quantum Signatures of Chaos	Shohini Ghose	2012-11-21	Scientific Series	View details
Massive gravitons, the cosmological constant and new directions in gravity		2012-11-14	Scientific Series	View details
An introduction to quantum channels and their capacities	Graeme Smith	2012-11-07	Scientific Series	View details
Astrophysical shear-driven turbulence	Jeremy Goodman	2012-10-17	Scientific Series	View details
Warm Superconductors	Baskaran Ganapathy	2012-10-10	Scientific Series	View details
New Observations about the Renormalization Group Flow	Zohar Komargodski	2012-09-26	Scientific Series	View details
The Higgs Boson and speculative particle physics	Mark Wise	2012-09-19	Scientific Series	View details
A Journalist's Perspective on Science Media	Ivan Semeniuk	2012-06-20	Scientific Series	View details

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