Related papers: Thermal Equilibrium in String Theory in the Hagedo…
We study string-gas cosmology in dilaton gravity, inspired by the fact that it naturally arises in a string theory context. Our main interest is the thermodynamical treatment of the string-gas and the resulting implications for the…
This thesis concerns the study of high-temperature string theory on curved backgrounds, generalizing the notions of Hagedorn temperature and thermal scalar to general backgrounds. Chapter 2 contains a review on string thermodynamics in flat…
Following the conjectured duality between near-horizon NS5-branes and little string theory, the string-corrected thermodynamics of near-horizon NS5-branes is studied and found to agree with the statistical thermodynamics of a 5+1…
We analyze the thermodynamics of NS 5-branes as the temperature approaches the NS 5-branes' Hagedorn temperature, and conclude that the dynamics of ``Little String Theory'' is a new universality class of interacting strings. First we point…
Thermal duality, which relates the physics of closed strings at temperature T to the physics at the inverse temperature 1/T, is one of the most intriguing features of string thermodynamics. Unfortunately, the classical definitions of…
Thermal duality is a relationship between the behaviour of heterotic string models of the $E(8)x E(8)$ or $SO(32)$ types at inversely related temperatures, a variant of T duality in the Euclidean regime. This duality would have consequences…
We explain how perturbative string theory can be viewed as an exactly renormalizable Weyl invariant quantum mechanics in the worldsheet representation clarifying why string scattering amplitudes are both finite and unambiguously normalized…
The divergence of the string partition function due to the exponential growth of states is a well-understood issue in flat spacetime. It can be interpreted as the appearance of tachyon modes above a certain temperature, known as the…
We calculate the thermal partition function in the canonical ensemble for type IIB superstrings in the plane wave background with constant null R-R 5-form. The Hagedorn temperature is found to be higher than the corresponding value for…
We discuss the high temperature behaviour of IIB strings in the maximally symmetric plane wave background, and show that there is a Hagedorn temperature. We discuss the map between strings in the pp-wave background and the dual…
We study the finite temperature properties of a recently introduced string bit model designed to capture some features of the emergent string in the tensionless limit. The model consists of a pair of bosonic and fermionic bit operators…
We discuss the correspondence between highly excited strings and black holes in the presence of angular momentum. At fixed imaginary angular velocity $\nu$, we show that free strings exhibit a Hagedorn instability due to a thermal-winding…
We study the behavior of a simple string bit model at finite temperature. We use thermal perturbation theory to analyze the high temperature regime. But at low temperatures we rely on the large $N$ limit of the dynamics, for which the exact…
We compute the high energy entropy and the equation of state of a gas of open superstrings in the infinite volume limit focusing on the calculation of the number of strings as a function of energy and volume. We do it in the fixed…
In string theory, black holes are expected to transition into string stars as their Hawking temperatures approach the Hagedorn temperature. We study string stars and their phase transitions in the Euclidean spacetime…
String gas cosmology is rewritten in the Einstein frame. In an effective theory in which a gas of closed strings is coupled to a dilaton gravity background without any potential for the dilaton, the Hagedorn phase which is quasi-static in…
According to the standard prescriptions, zero-temperature string theories can be extended to finite temperature by compactifying their time directions on a so-called "thermal circle" and implementing certain orbifold twists. However, the…
We extend the analysis of the recently obtained stringy cosmological solutions induced by thermal and quantum effects, once space-time supersymmetry is spontaneously broken by geometrical fluxes. Cases in which more than one modulus…
Physical arguments stemming from the theory of black-hole thermodynamics are used to put constraints on the dynamics of closed-string tachyon condensation in Scherk--Schwarz compactifications. A geometrical interpretation of the tachyon…
The thermodynamics of type IIB superstring theory in the maximally supersymmetric plane wave background is studied. We compute the thermodynamic partition function for non-interacting strings exactly and the result differs slightly from…