2003/07/27 by Daniel Brace, Carlos A. R. Herdeiro, Carlos Herdeiro +1
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Noncommutative and Quantum Gravity Theories #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.69.066010
published as Phys.Rev. D69 (2004) 066010 · 42 pages, LaTeX, 2 figures
arxiv created 2003/07/27 · openalex publication_date 2004/03/31 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We consider Neveu-Schwarz (NS) pp waves with spacetime supersymmetry. Upon compactification of a spacelike direction, these backgrounds develop closed null curves (CNCs) and closed timelike curves (CTCs), and are U dual to supersymmetric G"odel type universes. We study classical and quantum strings in this background, with emphasis on the strings winding around the compact direction. We consider two types of strings: long strings stabilized by NS flux and rotating strings which are stabilized against collapse by angular momentum. Some of the latter strings wrap around CNCs and CTCs, and are thus a potential source of pathology. We analyze the partition function, and in particular discuss the effects of these string states. Although our results are not conclusive, the partition function seems to be dramatically altered due to the presence of CNCs and CTCs. We discuss some interpretations of our results, including a possible sign of unitary violation.