While the accumulation of long wavelength modes during inflation wreaks havoc
on the large scale structure of spacetime, the question of even observability
of their presence by any local observer has lead to considerable confusion.
Though it is commonly agreed that infrared effects are not visible to a single
sub-horizon observer at late times, we argue that the question is less trivial
for a \emph{patient observer} who has lived long enough to have a record of the
state before the soft mode was created. Though classically there is no
obstruction to measuring this effect locally, we give several indications that
quantum mechanical uncertainties censor the effect, rendering the observation
of long modes ultimately forbidden.Comment: 7 pages, awarded honorable mention in the 2017 Gravity Research
Foundation Essays on Gravitation competitio
