Higher covariant derivatives, exact beta-function and finiteness
Семинары
Семинар «Теория квантового поля»
Дата и время: среда, 28 октября 2020 г., в 11:00
Место: Онлайн конференция в Zoom, Лаборатория теоретической физики им. Н.Н. Боголюбова
Тема семинара: «Higher covariant derivatives, exact beta-function and finiteness»
Докладчик: А. Е. Казанцев (МГУ)
Аннотация:
In this work we present the calculation of the two-loop anomalous dimension in N=1 supersymmetric gauge theory regularized by higher covariant derivatives. With a recently obtained all-order proof of the exact Novikov—Shifman—Vainshtein—Zakharov beta-function, we also give the three-loop beta-function in the scheme with minimal subtraction of divergent logarithms. The anomalous dimension obtained depends on a number of parameters that define the regularization, namely the Pauli—Villars masses and the form of regulator functions. We show that with a certain choice of these parameters one-loop finite theory can be made two-loop finite (which, as we argue, is generally not so). In this case the beta-function vanishes up to and including the three-loop approximation.