Comment on "Novel Attractive Force between Ions in Quantum Plasmas" [Shukla, Eliasson, PRL 108, 165007 (2012), arXiv:1112.5556]

Abstract

It is shown that the attractive force between ions in a degenerate quantum plasma, recently predicted by Shukla and Eliasson [Shukla, Eliasson, PRL 108, 165007 (2012), arXiv:1112.5556] using a generalized quantum hydrodynamical model, is dwarfed by the attractive force due to kinetic effects that cannot be accounted for in the previous model. This suggests that the problem of charge shielding in a degenerate quantum plasma should necessarily be a kinetic one, providing the dominant part of the attractive force.