Two-Loop Beta Functions without Feynman Diagrams
نویسندگان
چکیده
منابع مشابه
Algorithmic Calculation of Two-loop Feynman Diagrams *
In a recent paper [1] a new powerful method to calculate Feynman diagrams was proposed. It consists in setting up a Taylor series expansion in the external momenta squared. The Taylor coefficients are obtained from the original diagram by differentiation and putting the external momenta equal to zero. It was demonstrated that by a certain conformal mapping and subsequent resummation by means of...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 1997
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.79.3573