  We study the generation of low-energy couplings induced by quantum
fluctuations within the O(4)-symmetric quark-meson model. To this end, we
compute the functional renormalization group flow of the linearly realized
quark-meson model including higher-derivative interactions and subsequently
transform the resulting effective action into a nonlinear effective pion
action. The latter is referred to as the low-energy limit of the O(4)
quark-meson model. The present study may be considered as a preparatory work
for the dynamical generation of low-energy couplings from functional QCD
fluctuations in order to determine meaningful renormalization scales for purely
pionic models.
