Past String Theory Seminar

I present a calculation of the moduli Kahler potential for M-theory

on a G_2 manifold in a large radius approximation. The result is used to

analyze moduli dynamics and moduli stabilization in the context of the

associated four-dimensional effective theory.

I discuss gauge theories for commutative but non-associative algebras

related to the SO(2k+1) covariant finite dimensional fuzzy 2k-sphere

algebras. A consequence of non-associativity is that gauge fields and

gauge parameters have to be generalized to be functions of coordinates as

well as derivatives. The usual gauge fields depending on coordinates only

are recovered after a partial gauge fixing.The deformation parameter for

these commutative but non-associative algebras is a scalar of the rotation

group. This suggests interesting string-inspired algebraic deformations of

spacetime which preserve Lorentz-invariance.

The talk will be based on hepth/0310153