/ 06 06 00 8 v 1 1 J un 2 00 6 Feynman problem in the noncommutative case

ar X iv : h ep - t h / 06 06 00 8 v 1 1 Ju n 20 06 Feynman problem in the noncommutative case

In the context of the Feynman’s derivation of electrodynamics, we show that noncommutativity allows other particle dynamics than the standard formalism of electrodynamics.

ar X iv : h ep - t h / 06 06 07 5 v 1 8 J un 2 00 6 Boundary Terms in Supergravity and Supersymmetry ∗

We begin with the simplest possible introduction to supergravity, and then discuss its spin 3/2 stress tensor. Next, we discuss boundary conditions on fields and boundary actions for N = 1 supergravity. Finally, we discuss new boundary contributions to the mass and central charge of monopoles in N = 4 super Yang-Mills theory. All models are in 3+1 dimensions. YITP-SB-06-21

ar X iv : a st ro - p h / 06 06 12 4 v 1 6 J un 2 00 6 Inhomogeneous Cosmology , Inflation and Late - Time Accelerating Universe

An inhomogeneous cosmology describing a spacetime without symmetry is shown to be able to inflate the early universe and explain the late-time acceleration of the universe without a cosmological constant and negative pressure dark energy and avoid the coincidence problem. e-mail: [email protected]

ar X iv : h ep - t h / 06 12 12 8 v 1 1 3 D ec 2 00 6 Riemannian Geometry of Noncommutative Surfaces

ar X iv : h ep - t h / 06 03 12 5 v 1 1 5 M ar 2 00 6 hep - th / 0603125 ITP – UH – 05 / 06 Noncommutative Instantons on C

We construct explicit solutions of the Hermitian Yang-Mills equations on the noncommutative space C θ . In the commutative limit they coincide with the standard instantons on CP written in local coordinates.