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arXiv · hep-th/0312101

Effectively Closed Infinite-Genus Surfaces and the String Coupling

Simon Davis
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Abstract

The class of effectively closed infinite-genus surfaces, defining the completion of the domain of string perturbation theory, can be included in the category $O_G$, which is characterized by the vanishing capacity of the ideal boundary. The cardinality of the maximal set of endpoints is shown to be $2^{\mit N}$. The product of the coefficient of the genus-g superstring amplitude in four dimensions by $2^g$ in the $g\to \infty$ limit is an exponential function of the genus with a base comparable in magnitude to the unified gauge coupling. The value of the string coupling is consistent with the characteristics of configurations which provide a dominant contribution to a finite vacuum amplitude.

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Simon Davis. 2003-12-10. Effectively Closed Infinite-Genus Surfaces and the String Coupling. https://doi.org/10.1142/s0217751x05021245

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