6.4 Spacetime Topology Change
by Joseph Polchinski
This subsection is not directly related to black holes, but deals with another exotic question in quantum gravity. Gravity is due to the bending of spacetime. It is an old question, whether spacetime can not only bend but break: does its topology as well as its geometry evolve in time?
Again, string theory provides the tools to answer this question. The answer is ‘yes’ — under certain controlled circumstances the geometry can evolve as shown schematically in figure 9.
Posted below is Steinhardt informtaion, and his cyclical universe have been highlighted for consideration. The informtaion about the Planck satelitte ready for deployment in 2007 should open our eyes to a few of the issues that are evolving.
No comments:
Post a Comment