Talk detail

Participant	Visser, Matt
Institution	Victoria University of Wellington - School of Mathematics - Wellington - PO Box 600 - New Zealand

Session	BH6	Accepted	Yes	Order	5	Time	17:00	30'
Talk	Oral abstract	Title	Sparsity of the Hawking flux
Coauthors	Visser, Matt; Gray, Finnian; Schuster, Sebastian; Van-Brunt, Alexander
Abstract	The Hawking flux that reaches spatial infinity is extremely sparse and thin, with the Hawking quanta slowly dribbling out of the black hole one-by-one. The typical time interval between the quanta reaching infinity is larger than the timescale set by the energy of the quanta by factors of many hundreds. Among other things, this means that the Hawking evaporation of a black hole should be viewed as a sequential cascade of 3-body decays.
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Session	AT3	Accepted	Yes	Order	4	Time	15:35	25'
Talk	Oral abstract	Title	Buchert averaging and energy conditions
Coauthors	Visser, Matt
Abstract	A key feature of Buchert averaging is the realization that, either with spatial averaging or averaging over a suitably defined ensemble of spacetimes, the average of the Einstein tensor is typically not equal to the Einstein tensor of the average spacetime. The discrepancy can be viewed as an "effective" stress-energy, one that often violates the classical energy conditions. A particularly attractive example of this phenomenon arises when one considers spatial averages in a conformal-FLRW (CFLRW) cosmology or the ensemble average over conformal deformations of a specific FLRW geometry. These CFLRW-based models are particularly tractable, (and particularly attractive for observational reasons; the CMB is not distorted). Furthermore one can now prove some rigorous theorems regarding the interplay between Buchert averaging and the classical energy conditions.
Pdf file