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PERIMETER INSTITUTE RECORDED SEMINAR ARCHIVE

Displaying all lectures given by: Rafael Sorkin


A Lisp "scratch-pad" for working with posets
Speaker(s): Rafael Sorkin
Abstract:
Date: 09/02/2012 - 4:35 pm

Quantum Theory - Lecture 9
Speaker(s): Rafael Sorkin
Abstract:
Date: 22/09/2011 - 1:30 pm

Quantum Theory - Lecture 8
Speaker(s): Rafael Sorkin
Abstract:
Date: 21/09/2011 - 3:15 pm

An Invitation to Causal Sets - Lecture 5
Abstract: Introduction to the causal set approach to quantum gravity and overview of current research in causal set theory
Date: 22/10/2010 - 11:00 am

An Invitation to Causal Sets - Lecture 4
Abstract: Introduction to the causal set approach to quantum gravity and overview of current research in causal set theory
Date: 21/10/2010 - 11:00 am

An Invitation to Causal Sets - Lecture 3
Abstract: Introduction to the causal set approach to quantum gravity and overview of current research in causal set theory
Date: 20/10/2010 - 11:00 am

An Invitation to Causal Sets - Lecture 2
Abstract: Introduction to the causal set approach to quantum gravity and overview of current research in causal set theory
Date: 19/10/2010 - 11:30 am

An Invitation to Causal Sets - Lecture 1
Abstract: Introduction to the causal set approach to quantum gravity and overview of current research in causal set theory
Date: 18/10/2010 - 11:00 am

What is a quantal reality?
Speaker(s): Rafael Sorkin
Abstract: I will rephrase the question, "What is a quantal reality?" as "What is a quantal history?" (the word history having here the same meaning as in the phrase sum-over-histories). The answer I will propose modifies the rules of logical inference in order to resolve a ... read more
Date: 01/06/2009 - 12:15 pm

Is the cosmological constant a nonlocal quantum residue of discreteness of the causal set type?
Speaker(s): Rafael Sorkin
Abstract: The currently accelerating Hubble expansion is in accord with the old heuristic prediction, from causal set theory, of a fluctuating and ever-present cosmological "constant''. More recently, a phenomenological model based on certain of the ideas behind the prediction has been devised, but i... read more
Date: 27/05/2009 - 11:00 am

Ten Theses on Black Hole Entropy
Speaker(s): Rafael Sorkin
Abstract: I present a viewpoint on black hole thermodynamics according to which the entropy: derives from horizon 'degrees of freedom''; is finite because the deep structure of spacetime is discrete; is ``objective'' thanks to the distinguished coarse graining provided by the horizon; and obeys the second law... read more
Date: 23/01/2009 - 9:00 am

Solved and unsolved problems of time in quantum gravity
Speaker(s): Rafael Sorkin
Abstract: I will identify six 'problems of time' that arise in connection with quantum gravity and review the extent to which some of them can be regarded as solved, highlighting the very different aspects that they assume depending on one's starting point: Hamiltonian vs. path-integral, discrete vs continuou... read more
Date: 02/10/2008 - 9:00 am

Lecture 14B
Speaker(s): Rafael Sorkin
Abstract: The Problem of Time in Quantum Gravity and Cosmology
Date: 23/04/2008 - 8:00 pm

Lecture 14A
Speaker(s): Rafael Sorkin
Abstract: The Problem of Time in Quantum Gravity and Cosmology
Date: 23/04/2008 - 7:00 pm

Does quantum gravity give rise to an observable nonlocality?
Speaker(s): Rafael Sorkin
Abstract: If spacetime is "quantized" (discrete), then any equation of motion compatible with the Lorentz transformations is necessarily non-local. I will present evidence that this sort of nonlocality survives on length scales much greater than Planckian, yielding for example a nonlocal effective wave-equat... read more
Date: 17/01/2007 - 2:00 pm
Series: Colloquium

A discrete, Lorentz-invariant wave equation and its continuum limit
Speaker(s): Rafael Sorkin
Abstract:
Date: 05/09/2006 - 2:00 pm

Strings/Quantum Gravity 5
Speaker(s): Rafael Sorkin
Abstract:
Date: 08/06/2006 - 3:50 pm
Collection: Theory Canada 2

Is a past-finite causal order the inner basis of spacetime?
Speaker(s): Rafael Sorkin
Abstract: The causal set -- mathematically a finitary partial order -- is a candidate discrete substratum for spacetime. I will introduce this idea and describe some aspects of causal set kinematics, dynamics, and phenomenology, including, as time permits, a notion of fractal dimension, a (classical) dynamics... read more
Date: 07/09/2005 - 2:00 pm
Series: Colloquium

Audience Night
Abstract: The final part of the 04-05 Public Events series turns the spotlight on you. ItÂ’s your chance to ask a panel of Perimeter researchers for their thoughts on a wide variety of scientific topics.
Date: 01/06/2005 - 7:00 pm

Is a past finite order the inner basis of space-time?
Speaker(s): Rafael Sorkin
Abstract:
Date: 29/10/2004 - 11:30 am
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