Spectral Flow in Instanton Computations and the \boldmath{$\b$} functions

Alexander Monin, Mikhail Shifman, Arkady Vainshtein

We discuss various differences in the instanton-based calculations of the $\beta$ functions in theories such as Yang-Mills and $\mathbb{CP}(N-1)$ on one hand, and $\lambda {\varphi }^4$ theory wit…