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Hagedorn transition and chronology protection in string theory

Miguel S. Costa·Carlos A. R. Herdeiro·J. Penedones·N. Sousa
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Abstract

We conjecture chronology is protected in string theory due to the condensation of light winding strings near closed null curves. This condensation triggers a Hagedorn phase transition, whose end-point target space geometry should be chronological. Contrary to conventional arguments, chronology is protected by an infrared effect. We support this conjecture by studying strings in the O-plane orbifold, where we show that some winding string states are unstable and condense in the non-causal region of spacetime. The one-loop string partition function has infrared divergences associated to the condensation of these states.

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Miguel S. Costa, Carlos A. R. Herdeiro, J. Penedones, N. Sousa. 2005-07-12. Hagedorn transition and chronology protection in string theory. https://doi.org/10.1016/j.nuclphysb.2005.08.022

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