A short introduction is given on the functional renormalization group method, putting
emphasis on its nonperturbative aspects. The method enables to find nontrivial fixed points …

Abstract The Renormalisation Group is a versatile tool for the study of many systems where
scale-dependent behaviour is important. Its functional formulation can be cast into the form …

This thesis deals with several aspects of non-perturbative calculations in low-dimensional
quantum field theories. It is split into two main parts: The first part focuses on method …

We compute the low-energy limit of the O (4)-symmetric quark-meson model as an effective
field theory for quantum chromodynamics (QCD) within the functional renormalization group …

We study a ϕ 4 theory at finite temperature in a finite volume. Quantum, thermal and volume
fluctuations are treated with the functional renormalization group. Specifically, we focus on …

We extend our recent computation of the low-energy limit of the linear O (4) quark-meson
model. The present analysis focuses on the transformation of the resulting effective action …

The requirement for the absence of spontaneous symmetry breaking in the d= 1 dimension
has been used to optimize the regulator dependence of functional renormalization group …

We investigate the flat phase of quantum polymerized phantom membranes by means of a
nonperturbative renormalization group approach. We first implement this formalism for …

A bstract We study the occurrence of spontaneous symmetry breaking (SSB) for O (N)
models using functional renormalization group techniques. We show that even the local …

In this paper we will discuss the derivation of the so-called vanishing beta function curves
which can be used to explore the fixed point structure of the theory under consideration. This …