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arXiv · alg-geom/9208001

Open String Diagrams I: Topological Type

Subhashis Nag·Parameswaran Sankaran
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Abstract

An arbitrary Feynman graph for string field theory interactions is analysed and the homeomorphism type of the corresponding world sheet surface is completely determined even in the non-orientable cases. Algorithms are found to mechanically compute the topological characteristics of the resulting surface from the structure of the signed oriented graph. Whitney's permutation-theoretic coding of graphs is utilized.

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Subhashis Nag, Parameswaran Sankaran. 1992-08-03. Open String Diagrams I: Topological Type. https://doi.org/10.1063/1.530357

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