  The interaction of light with rotating media has attracted recent interest
for both fundamental and applied studies including rotational Doppler shift
measurements. It is also possible to obtain amplification through the
scattering of light with orbital angular momentum from a rotating and absorbing
cylinder, as proposed by Zel'dovich more than 40 years ago. This amplification
mechanism has never been observed experimentally yet has connections to other
fields such as Penrose superradiance in rotating black holes. Here we propose a
nonlinear optics system whereby incident light carrying orbital angular
momentum drives parametric interaction in a rotating medium. The crystal
rotation is shown to take the phase-mismatched parametric interaction with
negligible energy exchange at zero rotation to amplification for sufficiently
large rotation rates. The amplification is shown to result from breaking of
anti-PT symmetry induced by the medium rotation.
