(adsbygoogle = window.adsbygoogle || []).push({}); The Trouble with "The Trouble with deSitter Space"

http://arxiv.org/abs/0705.1178

A global picture of quantum de Sitter space

Steven B. Giddings, Donald Marolf

17 pages, 1 figure

"Perturbative gravity about a de Sitter background motivates a global picture of quantum dynamics in `eternal de Sitter space,' the theory of states which are asymptotically de Sitter to both future and past. Eternal de Sitter physics is described by a finite dimensional Hilbert space in which each state is precisely invariant under the full de Sitter group. This resolves a previously-noted tension between de Sitter symmetry and finite entropy. Observables, implications for Boltzmann brains, and Poincare recurrences are briefly discussed."

Giddings is known as a string theorist but this is not a string paper. It finds a mistake in a 2002 paper by Leonard Susskind and others called "The Trouble with deSitter Space" http://arxiv.org/hep-th/0212209 [Broken]

Incidentally, many papers by people in the LQG community are cited---four by Rovelli, several by Ambjorn, others by Thiemann, Ashtekar, Gambini and Pullin. Doubtless still more but I didnt make a careful count. Since Giddings and Marolf are well-known people at KITP Santa Barbara it suggests a significant broadening of horizons.

As we have discussed here, with John Baez help, a substantial amount of nonstring QG research is currently heading in the deSitter direction---Baez was discussion Cartan geometry using the deSitter group instead of Poincaré---DSR (deformed special relativity) deals a lot with deSitter group. This paper may possibly be of interest and have usefulness in broader QG research outside of string.

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# The Trouble with The Trouble with deSitter Space

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