  Fossil turbulence processes are central to turbulence, turbulent mixing, and
turbulent diffusion in the ocean and atmosphere, in astrophysics and cosmology,
and in most other natural flows. George Gamov suggested in 1954 that galaxies
might be fossils of primordial turbulence produced by the Big Bang. John Woods
showed that breaking internal waves on horizontal dye sheets in the interior of
the stratified ocean form highly persistent remnants of these turbulent events,
which he called fossil turbulence. The dark mixing paradox of the ocean refers
to undetected mixing that must exist somewhere to explain why oceanic scalar
fields like temperature and salinity are so well mixed, just as the dark matter
paradox of galaxies refers to undetected matter that must exist to explain why
rotating galaxies don't fly apart by centrifugal forces. Both paradoxes result
from sampling techniques that fail to account for the extreme intermittency of
random variables involved in self-similar, nonlinear, cascades over a wide
range of scales; turbulent vorticity for dark mixing, and accreting
small-planetary-mass MACHO number density for dark matter.
