Abstract:
The formalism of projection Hamiltonians is applied to the N-component O(N)-invariant φ4 model in the Euclidean and p-adic spaces. We use two versions of the ε-expansion (with ε=4−d and ε=α−3d/2 where α is the renormalization group parameter) and evaluate the critical indices ν and η up to the second order of the perturbation theory. The results for the (4−d)-expansion then coincide with the known results obtained via the quantum-field renormalization-group methods. Our calculations give evidence that in dimension three, both expansions describe the same non-Gaussian fixed point of the renormalization group.
Citation:
M. D. Missarov, R. G. Stepanov, “Epsilon-expansion in the N-component φ4 model”, TMF, 146:3 (2006), 365–384; Theoret. and Math. Phys., 146:3 (2006), 304–320