Joint cosmology seminar at MIT:

Tuesday, October 2, 2012, 2:30 pm
Cosman Seminar Room
Center for Theoretical Physics
Building 6C, Room 6C-442
Massachusetts Institute of Technology
Refreshments at 2:00 in the same room

On ``Nothing''

Alex Dahlen
Berkeley

Abstract:

This talk is about ``nothing'': the state of zero metric from which spacetime can appear, and to which spacetime can disappear. By studying generalizations of Witten's ``bubble of nothing'' in the context of perturbatively-stabilized compact extra dimensions, I will show that ``nothing'' should be understood as an infinitely negatively curved spacetime. Armed with this understanding, I will show that a proposed mechanism for the appearance of spacetime from nothing -- the ``quantum creation of a universe'' of Hawking and Turok -- does not work.