Instantons and R 2 couplings in N = 4 String Theory Jeffrey
نویسنده
چکیده
We compute the gravitational coupling F1 for IIA string theory on K3× T 2 and use string-string duality to deduce the corresponding term for heterotic string on T . The latter is an infinite sum of gravitational instanton effects which we associate with the effects of Euclidean fivebranes wrapped on T . These fivebranes are the neutral fivebranes or zero size instantons of heterotic string theory.
منابع مشابه
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تاریخ انتشار 1996