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On the Nature of the Hagedorn Transition in NCOS Systems

J. L. F. Barbon·E. Rabinovici
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Abstract

We extend the study of the nature of the Hagedorn transition in NCOS systems in various dimensions. The canonical analysis results in a microscopic ionization picture of a bound state system in which the Hagedorn transition is postponed till irrelevancy. A microcanonical analysis leads to a limiting Hagedorn behaviour dominated by highly excited, long open strings. The study of the full phase diagram of the NCOS system using the AdS/CFT correspondence suggests that the microscopic ionization picture is the correct one. We discuss some refinements of the ionization mechanism for $d>2$ NCOS systems, including the formation of a temperature-dependent barrier for the process. Some possible consequences of this behaviour, including a potential puzzle for $d=5$, are discussed. Phase diagrams of a regularized form of NCOS systems are introduced and do accomodate a phase of long open strings which disappears in the strict NCOS limit.

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J. L. F. Barbon, E. Rabinovici. 2001-04-19. On the Nature of the Hagedorn Transition in NCOS Systems. https://doi.org/10.1088/1126-6708%2F2001%2F06%2F029

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