Stability of ${\phi }^4$-vector model: four-loop $\epsilon$ expansion study

L. Ts. Adzhemyan, A. Kudlis

The stability of $O(n)$-symmetric fixed point regarding the presence of vector-field term ($\sim h{p}_{\alpha }{p}_{\beta }$) in the ${\phi }^4$ field theory is analyzed. For this purpose, the four-loop r…