String Threshold corrections from Field Theory
نویسندگان
چکیده
A field theory approach to summing threshold effects to the gauge couplings in a two-torus compactification is presented and the link with the (heterotic) string calculation is carefully investigated. We analyse whether the complete UV behaviour of the theory may be described on pure field theory grounds, as due to momentum modes only. “Non-decoupling” effects of a small dimension are discussed. The role of modular invariance in ensuring a finite (heterotic) string result is addressed. 1 E-mail: [email protected] 2 E-mail: [email protected] 1
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