. FA ] 1 5 Fe b 19 99 Subsequences of frames

ar X iv : m at h / 99 02 08 6 v 1 [ m at h . SP ] 1 4 Fe b 19 99 THE REDUCED WAVE EQUATION IN LAYERED MATERIALS

/ 99 02 44 5 v 1 2 3 Fe b 19 99 UK / 99 - 03 Leading soft gluon production in high energy nuclear collisions 1

The leading soft gluon pT distribution in heavy ion collisions was obtained by Kovner, McLerran, and Weigert after solving classical Yang-Mills equations. I show explicitly this result can be understood in terms of conventional QCD perturbation theory. I also demonstrate that the key logarithm in their result represents the logarithm in DGLAP evolution equations.

ar X iv : a st ro - p h / 99 02 23 4 v 2 1 7 Fe b 19 99 OB ASSOCIATIONS

ep - p h / 99 02 46 3 v 1 2 5 Fe b 19 99 LU TP 99 - 05 February 1999 A Parametrization for K + → π + π − e + ν . †

We discuss various models and Chiral Perturbation Theory results for the Kl4 form factors F and G. We check in how much a simple parametrization with a few parameters can be used to extract information from experiment. Work supported in part by TMR, EC-Contract No. ERBFMRX-CT980169 (EURODAΦNE).

/ 99 02 20 1 v 1 2 6 Fe b 19 99 On the structure of exact effective action for N = 1 supersymmetric theories

We discuss the ways of constructing the exact superpotential for N=1 supersymmetric theories and propose a new approach. As a consequence , a new structure of the superpotential is found.