D-brane Dynamics and Creations of Open and Closed Strings after Recommbination

Abstract

A quantum-mechanical technique is used within the framework of U(2) super-Yang-Mills theory to investigate what happens in the process after recombination of two D-p-branes at one angle. Two types of initial conditions are considered, one of which with $p=4$ is a candidate of inflation mechanism. It is observed that the branes' shapes come to have three extremes due to localization of tachyon condensation. Furthermore, open string pairs connecting the decaying D-branes are shown to be created; most part of the released energy is used to create them. It also strongly suggests that creation of closed strings happens afterward. Closed strings as gravitational radiation from the D-branes are also shown to be created. A few speculations are also given on implications of the above phenomena for an inflation model.

Comments: 39pages,Latex,9 eps-figs,in v4 creation of closed strings discussed, energy dissipation by rads. replaced by that by creations of strings; in v5 logic to argue pair-creation of open strings corrected, their number density, energy distribution to them, energy flux of gravi. radiation evaluated quantitatively, 2 intuitive figs.added, 1 initial cond. modified: overlapping -> parallel, refs. on rolling tachyons added;in v6 distribution of the releassed energy corrected:its most part used to created open string pairs