On the High-Temperature Behaviour of the Closed Superstring

TL;DR

This paper investigates the high-temperature behavior of closed superstring theory, deriving a Laurent series for the free energy and analyzing the nature of the Hagedorn temperature, revealing potential metastability beyond this point.

Contribution

It provides an analytical continuation of the free energy Laurent series to study the critical Hagedorn temperature and its implications for string system stability.

Findings

Finite free energy contribution beyond Hagedorn temperature

Presence of an imaginary part indicating metastability

Analytical continuation of Laurent series

Abstract

The high-temperature expansion for closed superstring one-loop free energy is studied. The Laurent series representation is obtained and its sum is analytically continued in order to investigate the nature of the critical (Hagedorn) temperature. It is found that beyond this critical temperature the statistical sum contribution of the free energy is finite but has an imaginary part, signalling a possible metastability of the system.