Related papers: Exotic Fluids Made of Open Strings
We give examples of modeling the string free energy whose behavior mimics that of QCD: a power-law at high temperature and an exponential decrease at low temperature. Although the effective description is in terms of strings, no limiting…
In this paper, we investigate thermal equilibrium in string gas cosmology which is dominated by closed string.We consider two interesting regimes, Hagedorn and radiation regimes.We find that for short strings in small radius of Hagedorn…
We argue that, within the realm of gauge-gravity duality, for a large class of systems in a steady-state there exists an effective thermodynamic description. This description comes equipped with an effective temperature and a free energy,…
We show that the entropy of any black object in any dimension can be understood as the entropy of a highly excited string on the stretched horizon. The string has a gravitationally renormalized tension due to the large redshift near the…
We describe finite temperature N=4 superstrings in D=5 by an effective four-dimensional supergravity of the thermal winding modes that can become tachyonic and trigger the instabilities at the Hagedorn temperature. Using a domain-wall…
We discuss the thermal properties of string gases propagating in various D-brane backgrounds in the weak-coupling limit, and at temperatures close to the Hagedorn temperature. We determine, in the canonical ensemble, whether the Hagedorn…
A novel representation ---in terms of a Laurent series--- for the free energy of string theory at non-zero temperature is constructed. The examples of open bosonic, open supersymmetric and closed bosonic strings are studied in detail. In…
Open superstrings at non-zero temperature are considered. A novel representation for the free energy (Laurent series representation) is constructed. It is shown that the Hagedorn temperature arises in this formalism as the convergence…
We discuss interacting, closed, bosonic and superstrings in thermal equilibrium at temperatures close to the Hagedorn temperature in flat space. We calculate S-matrix elements of the strings at the Hagedorn temperature and use them to…
The thermal equilibrium of string gas is necessary to activate the Brandenberger-Vafa mechanism, which makes our observed 4-dimensional universe enlarge. Nevertheless, the thermal equilibrium is not realized in the original setup, a problem…
We investigate numerically the configurational statistics of strings. The algorithm models an ensemble of global $U(1)$ cosmic strings, or equivalently vortices in superfluid $^4$He. We use a new method which avoids the specification of…
We consider an exactly solvable worldsheet string theory in the background of a black brane with a gauge field flux. Holographically, such a system can be interpreted as a field theory with finite number of degrees of freedom at finite…
We consider the thermodynamics of a color-confined phase of quantum chromodynamics (QCD) and pure gauge theory within a string-inspired model, corresponding to a physical spatial dimension, d = 3. We show that the physical mass spectrum of…
We consider early time cosmic evolution in string gas cosmology dominated by open strings attached to D-branes. After reviewing statistical properties of open strings in D-brane backgrounds, we use dilaton-gravity equations to determine the…
A framework for numerical evaluation of entropy-conservative volume fluxes in gas flows with internal energies is developed, for use with high-order discretization methods. The novelty of the approach lies in the ability to use arbitrary…
We study the high energy thermodynamics of Little String Theory, using its holographic description. This leads to the entropy-energy relation $S=\beta_H E+\alpha\log E+O(1/E)$. We compute $\alpha$ and show that it is negative; as a…
Thermodynamic properties such as temperature, pressure, and internal energy have been defined for finite binary strings from equilibrium distribution of a chosen computable measure. It is demonstrated a binary string can be associated with…
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…
We show that the string gas - a perfect fluid with the equation of state $p = -\frac13 \rho$ possesses rather interesing properties. In Friedmann universes its presence can can change the observable topology of the space; in the spherically…
In these lecture notes I give a pedagogical introduction to the thermodynamics of ideal string gases. The computation of thermodynamic quantities in the canonical ensemble formalism will be shown in detail with explicit examples. Attention…