Explicit modular invariant two-loop superstring amplitude relevant for R4
نویسندگان
چکیده
منابع مشابه
Explicit Modular Invariant Two-Loop Superstring Amplitude Relevant for R
In this note we derive an explicit modular invariant formula for the two loop 4-point amplitude in superstring theory in terms of a multiple integral (7 complex integration variables) over the complex plane which is shown to be convergent. We consider in particular the case of the leading term for vanishing momenta of the four graviton amplitude, which would correspond to the two-loop correctio...
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ژورنال
عنوان ژورنال: Journal of High Energy Physics
سال: 1999
ISSN: 1029-8479
DOI: 10.1088/1126-6708/1999/06/011