Abstract
It has been proposed that the string diagrams of closed string field theory be defined by a minimal area problem that requires that all nontrivial homotopy curves have length greater than or equal to 2π. Consistency requires that the minimal area metric be flat in a neighbourhood of the punctures. The theorem proven in this paper, yieds a criterion which if satisfied, will ensure this requirement. The theorem states roughly that the metric is flat in an open set,U if there is a unique closed curve of length 2π through every point inU and all of these closed curves are in the same free homotopy class.
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Communicated by S.-T. Yau
Supported in part by funds provided by the US Department of Energy (DOE) under contract # DE-AC02-76ER03069
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Ranganathan, K. A criterion for flatness in minimal area metrics that define string diagrams. Commun.Math. Phys. 146, 429–445 (1992). https://doi.org/10.1007/BF02097012
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DOI: https://doi.org/10.1007/BF02097012