  Fast pairwise conversions of neutrinos may affect the flavor distribution in
the core of neutrino-dense sources. We explore the interplay between collisions
and fast conversions within a simplified framework that assumes
angle-independent, direction-changing collisions in a neutrino gas that has no
spatial inhomogeneity. Counter to expectations, we find that collisions may
enhance fast flavor conversions instead of damping them. Our work highlights
the need to take into account the feedback of collisions on the neutrino
angular distributions self-consistently, in order to predict the flavor outcome
in the context of fast pairwise conversions reliably.
