I define and study TQFTs which generalize the Dijkgraaf-Witten
TQFT and can be described on a lattice using discrete 1-form and
2-form gauge fields. The gauge group is replaced by a gauge
2-group. It is proposed that 2-group TQFTs classify gapped...
We present concrete solutions with accelerated expansion in
string theory, requiring a small, tractable list of stress energy
sources. We explain how this construction (and others in progress)
evades previous no go theorems for simple accelerating...
Motivated by the connection between 4-manifolds and 2d N=(0,2)
theories, we study the dynamics of a fairly large class of 2d
N=(0,2) gauge theories. We see that physics of such theories is
very rich, much as the physics of 4d N=1 theories. We...
