Key points are not available for this paper at this time.
Neutrinos mediate long range forces among macroscopic bodies in a vacuum. When the bodies are placed in the neutrino cosmic background, these forces are modified. Indeed, at distances long compared to the scale T^-1, the relic neutrinos completely screen off the two-neutrino exchange force, whereas for small distances the interaction remains unaffected.
Ferrer et al. (Thu,) studied this question.