Testing for New Physics: Neutrinos and the Primordial Power Spectrum
  We test the sensitivity of neutrino parameter constraints from combinations
of CMB and LSS data sets to the assumed form of the primordial power spectrum
(PPS) using Bayesian model selection. Significantly, none of the tested
combinations, including recent high-precision local measurements of
$\mathrm{H}_0$ and cluster abundances, indicate a signal for massive neutrinos
or extra relativistic degrees of freedom. For PPS models with a large, but
fixed number of degrees of freedom, neutrino parameter constraints do not
change significantly if the location of any features in the PPS are allowed to
vary, although neutrino constraints are more sensitive to PPS features if they
are known a priori to exist at fixed intervals in $\log k$. Although there is
no support for a non-standard neutrino sector from constraints on both neutrino
mass and relativistic energy density, we see surprisingly strong evidence for
features in the PPS when it is constrained with data from Planck 2015, SZ
cluster counts, and recent high-precision local measurements of $\mathrm{H}_0$.
Conversely combining Planck with matter power spectrum and BAO measurements
yields a much weaker constraint. Given that this result is sensitive to the
choice of data this tension between SZ cluster counts, Planck and
$\mathrm{H}_0$ measurements is likely an indication of unmodeled systematic
bias that mimics PPS features, rather than new physics in the PPS or neutrino
sector.
