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PERIMETER INSTITUTE RECORDED SEMINAR ARCHIVE

Displaying all lectures given by: Brendan Foster


PIRSA:08100050  ( MP4 Medium Res , MP3 , PDF ) Which Format?
Dirac's penumbra: constraints and gauge transformations in reparametrization invariant theories
Speaker(s): Brendan Foster
Abstract: A simple theorem of Dirac identifies primary first-class constraints as generators of transformations, 'that do not affect the physical state'. This result has profound implications for the definition of physical states and observables in the quantization of constrained systems, and leads to one asp... read more
Date: 07/10/2008 - 4:00 pm

PIRSA:06120033  ( MP4 Medium Res , MP3 , PDF ) Which Format?
Aethereal Gravity
Speaker(s): Brendan Foster
Abstract: Hints from quantum gravity suggest that a preferred frame may actually exist. One way to accommodate such a frame in general relativity without sacrificing diffeomorphism invariance is to couple the metric to a dynamical, time like, unit-norm vector field--the "aether". I will discuss properties an... read more
Date: 06/12/2006 - 4:30 pm

PIRSA:06090021  ( MP4 Medium Res , MP3 , PDF ) Which Format?
Do background independent approaches to quantum gravity have something to say about this question?
Speaker(s): Brendan Foster
Abstract: The question of how to describe a natural ultraviolet cutoff in an expanding space-time is of significance in several respects. First, it concerns the fate of general covariance in the presence of a natural UV cutoff. Second, it concerns the continued generating of degrees of freedom through expansi... read more
Date: 05/09/2006 - 11:00 am
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