Renormalisability of the 2PI-Hartree approximation of multicomponent scalar models in the broken symmetry phase

Understand

Non-perturbative renormalisation of a general class of scalar field theories is performed at the Hartree level truncation of the 2PI effective action in the broken symmetry regime.

• Renormalised equations are explicitly constructed for the one- and two-point functions.
• The non-perturbative counterterms are deduced from the conditions for the cancellation of the overall and the subdivergences in the complete Hartree-Dyson-Schwinger equations, with a transparent method.
• The procedure proposed in the present paper is shown to be equivalent to the iterative renormalisation method of Blaizot et al., Nucl.