2007/12/31 by Dimitri P. Skliros, Dimitri Skliros, Mark Hindmarsh
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #hep-th
paper · pdf · doi:10.1103/physrevd.78.063539
published as Phys.Rev.D78:063539,2008 · 12 pages, 4 figures, more details presented in string thermodynamics section, to be published in Physical Review D
arxiv created 2008/07/31 · openalex publication_date 2008/09/25 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We calculate the equation of state of a gas of strings at high density in a large toroidal universe and use it to determine the cosmological evolution of background metric and dilaton fields in the entire large radius Hagedorn regime, (lnS)1/d\ensuremath≪R\ensuremath≪S1/d (with S the total entropy). The pressure in this regime is not vanishing but of O(1), while the equation of state is proportional to volume, which makes our solutions significantly different from previously published approximate solutions. For example, we are able to calculate the duration of the high-density Hagedorn phase, which increases exponentially with increasing entropy, S. We go on to discuss the difficulties of the scenario, quantifying the problems of establishing thermal equilibrium and producing a large but not too weakly coupled universe.