  The phase structure of baryonic matter is investigated with focus on the role
of fluctuations beyond the mean-field approximation. The prototype test case
studied is the chiral nucleon-meson model, with added comments on the chiral
quark-meson model. Applications to the liquid-gas phase transition in nuclear
matter and extensions to dense matter are performed. The role of vacuum
fluctuations and thermal excitations is systematically explored. It is pointed
out that such fluctuations tend to stabilise the hadronic phase characterised
by spontaneously broken chiral symmetry, shifting the chiral restoration
transition to very high densities. This stabilisation effect is shown to be
further enhanced by additional dynamical fluctuations treated with functional
renormalisation group methods.
