Twisting S-branes

TL;DR

This paper constructs smooth, non-singular time-dependent supergravity solutions with a helical twist, revealing de Sitter phases, tachyon condensation, and closed timelike curves in various limits, advancing understanding of S-brane dynamics.

Contribution

It introduces new analytic supergravity solutions for S-branes with a helical twist, exploring their de Sitter expansion and CTC formation, which were not previously characterized.

Findings

De Sitter expansion in extremal limit

Formation and decay of twisted circles

Closed timelike curves for small twists

Abstract

Smooth time dependent supergravity solutions corresponding to analytic continuations of Kerr black holes are constructed and limits with a local de Sitter phase are found. These solutions are non-singular due to a helical twist in space and a fine tuning of the energy flow in the spacetime. For the extremal limit in which the mass and twist parameters are equal the S-brane undergoes de Sitter expansion. Subextremal limits show the formation and decay of a twisted circle and closed string tachyon condensation backreaction effects can be followed. For small values of the twist deformation, a short lived ergosphere envelopes the S-brane and leads to the production of closed timelike curves.