Please explain..

New Views of the Universe: The Kavli Inaugural Symposium in honor of David Schramm (2005), Preliminary Program

Cosmology interests me, even though it is a difficult field to understand. But then, with an abstract like this for a talk to be given at conference in Chicago later this month, who can blame me?:

"The large number of vacua in the stringy landscape may lead to interesting new cosmology. First, tunneling between from one vacuum to another (e.g. tunneling through a series of minima in a tilted cosine potential) provides a new mechanism for inflation: Chain Inflation. Second, a dynamical solution to the cosmological constant problem may be provided by a field with the same potential but without tunneling. After inflation, the universe reheats, and different regions of the universe fall into different minima of the potential. Domain walls shove aside higher energy vacua in favor of lower energy ones, but it is shown that this process stops before the universe can fall into very negative energy vacua. Gravitation itself provides a cutoff at a minimum vacuum energy, thereby leaving the universe with a small cosmological constant comparable in magnitude to the current vacuum energy."