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arXiv · hep-th/9701142

Dilute D-Instantons at Finite Temperature

J. L. F. Barbon·M. A. Vazquez-Mozo
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Abstract

We discuss Dirichlet instanton effects on type-IIB string Thermodynamics. We review some general properties of dilute D-instanton gases and use the low-energy supergravity solutions to define the normalization of the instanton measure, as well as the effects of long-range interactions. Thermal singularities in the single-instanton sector are due to tachyonic winding modes of Dirichlet open strings. Purely bosonic D-instantons induce in this way hard infrared singularities that ruin the weak-coupling expansion in the microcanonical ensemble. However, type-IIB D-instantons, give smooth contributions at the Hagedorn temperature, and the induced mass and coupling of the axion field are insufficient to change the first-order character of the phase transition in the mean field approximation.

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J. L. F. Barbon, M. A. Vazquez-Mozo. 1997-04-28. Dilute D-Instantons at Finite Temperature. https://doi.org/10.1016/s0550-3213(97)00256-3

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