Supercritical linear dilaton capping state using Interpolating functions

TL;DR

This paper explores the Supercritical Linear Dilaton phase in string theory, proposing a method to define a well-behaved initial state using interpolating functions, despite divergences in naive calculations.

Contribution

It introduces a strategy to construct the capping state in SCLD backgrounds via interpolating functions within a strong coupling completion of string theory.

Findings

Proposes a method to define initial states in SCLD backgrounds.

Shows the background is well-defined in the far future despite divergences.

Provides a general strategy using S-duality for constructing the completion.

Abstract

We consider time dependent backgrounds with a time-like linear dilaton which leads to a weakly coupled theory at asymptotic future known as the Supercritical Linear Dilaton (SCLD) phase. Even after projecting out the tachyon there are naive divergences in the partition function due to the spectrum of relevant deformations. Although the partition function seems divergent, the background is actually well defined in the far future due to vanishing backreactions, provided we start from an appropriate initial state called the "capping" state. We use the technique of interpolating functions to construct this state by embedding the SCLD phase in a strong coupling completion of string theory. Although we are unable construct a specific example, we do provide the general strategy in cases where S-duality may provide the completion.