Strong-Coupling $ϕ^4$-Theory in $4- ε$ Dimensions and Critical Exponents

Abstract

With the help of variational perturbation theory we continue the renormalization constants $ϕ^4$-theories in $4- ε$ dimensions to strong bare couplings $g_0$ and find their power behavior in $g_0$, thereby determining all critical exponents without renormalization group techniques.