Strings in a Time-Dependent Orbifold
نویسندگان
چکیده
منابع مشابه
Strings in a Time-Dependent Orbifold
We consider string theory in a time dependent orbifold with a null singularity. The singularity separates a contracting universe from an expanding universe, thus constituting a big crunch followed by a big bang. We quantize the theory both in light-cone gauge and covariantly. We also compute some tree and one loop amplitudes which exhibit interesting behavior near the singularity. Our results a...
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We review the construction of time-dependent backgrounds with space-like singularities. We mainly consider exact CFT backgrounds. The algebraic and geometric aspects of these backgrounds are discussed. Physical issues, results and difficulties associated with such systems are reviewed. Finally, we present some new results: a two dimensional cosmology in the presence of an Abelian gauge field de...
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ژورنال
عنوان ژورنال: Journal of High Energy Physics
سال: 2002
ISSN: 1029-8479
DOI: 10.1088/1126-6708/2002/06/045