Winding String Condensation and Noncommutative Deformation of Spacelike Singularity

TL;DR

This paper explores how winding string production in matrix models can resolve spacelike singularities in Misner space, leading to noncommutative spacetime structures without relying on closed string tachyons.

Contribution

It demonstrates a new mechanism involving winding strings for singularity resolution and noncommutative deformation in Misner space.

Findings

Winding string production can resolve spacelike singularities.

Space and time become noncommutative due to winding strings.

Calculated four-open-string cylinder amplitudes to analyze bulk-boundary coupling.

Abstract

In a previous paper (hep-th/0509067) using matrix model, we showed that closed string tachyons can resolve spacelike singularity in one particular class of Misner space (with anti-periodic boundary conditions for fermions around the spatial circle). In this note, we show that for Misner space without closed string tachyons, there also exists a mechanism to resolve the singularity in the context of the matrix model, namely cosmological winding string production. We show that here space and time also become noncommutative due to these winding strings. Employing optical theorem, we study the bulk boundary coupling by calculating the four-open-string cylinder amplitudes.