Scalar Bispectrum Beyond Slow-Roll in the Unified EFT of Inflation
  We present a complete formulation of the scalar bispectrum in the unified
effective field theory (EFT) of inflation, which includes the Horndeski and
beyond-Horndeski Gleyzes-Langlois-Piazza-Vernizzi classes, in terms of a set of
simple one-dimensional integrals. These generalized slow-roll expressions
remain valid even when slow-roll is transiently violated and encompass all
configurations of the bispectrum. We show analytically that our expressions
explicitly preserve the squeezed-limit consistency relation beyond slow-roll.
As an example application of our results, we compute the scalar bispectrum in a
model in which potential-driven G-inflation at early times transitions to
chaotic inflation at late times, showing that our expressions accurately track
the bispectrum when slow-roll is violated and conventional slow-roll
approximations fail.
