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The string partition function in Hull's doubled formalism

David S Berman·Neil B Copland
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Abstract

T-duality is one of the essential elements of string theory. Recently, Hull has developed a formalism where the dimension of the target space is doubled so as to make T-duality manifest. This is then supplemented with a constraint equation that allows the connection to the usual string sigma model. This paper analyses the partition function of the doubled formalism by interpreting the constraint equation as that of a chiral scalar and then using holomorphic factorisation techniques to determine the partition function. We find there is quantum equivalence to the ordinary string once the topological interaction term is included.

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David S Berman, Neil B Copland. 2007-01-25. The string partition function in Hull's doubled formalism. https://doi.org/10.1016/j.physletb.2007.03.007

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