ar X iv : h ep - t h / 04 07 24 1 v 1 2 8 Ju l 2 00 4 Lightsheets , Branes and the Covariant Entropy Bound

ar X iv : h ep - t h / 04 08 12 5 v 1 1 7 A ug 2 00 4 Field theoretic models on covariant quantum spaces

ar X iv : h ep - t h / 05 03 04 3 v 3 1 8 Ju l 2 00 5 TAUP -

We study closed N = 2 strings on orbifolds of the form T /Z2 and C /Z2. We compute the torus partition function and prove its modular invariance. We analyze the BRST cohomology of the theory, construct the vertex operators, and compute three and four point amplitudes of twisted and untwisted states. We introduce a background of D-branes, and compute twist states correlators.

ar X iv : h ep - t h / 04 05 27 2 v 2 3 1 Ju l 2 00 4 Two fermion relativistic bound states

We consider the relativistic quantum mechanics of a two interacting fermions system. We first present a covariant formulation of the kinematics of the problem and give a short outline of the classical results. We then quantize the system with a general interaction potential and deduce the explicit equations in a spherical basis. The case of the Coulomb interaction is studied in detail by numeri...

ar X iv : h ep - p h / 04 07 14 9 v 1 1 3 Ju l 2 00 4 Automated calculations for massive fermion production with å ıTalc ∗

The package a˚ı T alc has been developed for the automated calculation of radiative corrections to two-fermion production at e + e − colliders.

ar X iv : h ep - t h / 04 07 26 6 v 1 2 9 Ju l 2 00 4 Cosmic Natural Selection

I make a number of comments about Smolin's theory of Cosmic Natural Selection.