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String Expansion as Large N Expansion of Gauge Theories

Michael Bershadsky·Zurab Kakushadze·Cumrun Vafa
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Abstract

We consider string perturbative expansion in the presence of D-branes imbedded in orbifolded space-time. In the regime where the string coupling is weak and $α'\to 0$, the string perturbative expansion coincides with `t Hooft's large N expansion. We specifically concentrate on theories with d=4 and ${\cal N}=0,1,2,4$, and use world-sheet orbifold techniques to prove vanishing theorems for the field theory beta functions to all orders in perturbation theory in the large N limit. This is in accord with recent predictions.

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Michael Bershadsky, Zurab Kakushadze, Cumrun Vafa. 1998-03-18. String Expansion as Large N Expansion of Gauge Theories. https://doi.org/10.1016/s0550-3213(98)00272-7

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