Local observer effect on the cosmological soft theorem
  Non-Gaussianities of primordial perturbations in the soft limit provide the
important information about the light degrees of freedom during inflation. The
soft modes of the curvature perturbations, unobservable for a local observer,
act as rescaling the spatial coordinates. We determine how the trispectrum in
the collapsed limit is shifted by the rescaling due to the soft modes. We find
the form of the inequality between $f_{\rm NL}$ and $\tau_{\rm NL}$ parameters
is not affected by the rescaling, demonstrating that the role of the inequality
as an indicator of the light degrees of freedom remains intact. We also comment
on the local observer effect on the consistency relation for ultra slow-roll
inflation.
