Linear Perturbations in a coupled cosmon-bolon cosmology
  We investigate linear perturbations in the recently proposed cosmon-bolon
model of coupled scalar field dark matter and quintessence. We provide an
analytical mechanism to average over the quick oscillations appearing both in
the background and at the perturbative level and evolve the effective equations
numerically. The resulting matter power spectra are used to predict total halo
number counts as well as substructure abundances in a typical galaxy by
employing the extended Press-Schechter excursion set approach. We discuss in
some detail the ambiguities arising in this formalism, starting from issues
with generalizing spherical collapse to our model to filter choices and
different barriers. The results are used to put a lower bound on the current
bolon mass of roughly $9 \times 10^{-22}$ eV.
