Anisotropic tensor modes from icosahedral inflation
  For icosahedral inflation, we compute the tensor modes' two-point function in
the presence of higher derivative corrections, and show that in general this
features anisotropies that are aligned with the underlying icosahedral
structure. The effect is small within the regime of validity of the effective
theory, but it is the leading contribution to a mixed correlator between the
two different helicities. We also estimate the magnitude of a similar effect
for a mixed scalar-tensor correlator, whose detailed computation we leave for
future work. Along the way, we clarify a number of aspects of the spin
decomposition of generic icosahedral-invariant physical quantities.
