2008/03/27 by R. J. Rivers, D. A. Steer
Mathematics · Physics and Astronomy · #Black Holes and Theoretical Physics #Stochastic processes and statistical mechanics #Theoretical and Computational Physics #hep-th
paper · pdf · doi:10.1103/physrevd.78.023521
published as Phys.Rev.D78:023521,2008
arxiv created 2008/03/27 · openalex publication_date 2008/07/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We investigate the Hagedorn transitions of string networks with Y-junctions as may occur, for example, with (p,q) cosmic superstrings. In a simplified model with three different types of string, the partition function reduces to three generalized coupled XY models. We calculate the phase diagram and show that, as the system is heated, the lightest strings first undergo the Hagedorn transition despite the junctions. There is then a second, higher, critical temperature above which infinite strings of all tensions, and junctions, exist. Conversely, on cooling to low temperatures, only the lightest strings remain, but they collapse into small loops.