Comment on “Multi-dimensional Instability of Dust Acoustic Waves in Magnetized Quantum Plasmas with Positive or Negative Dust”

Abstract

In a recent paper [D.N. Gao, Braz J Phys51, 66-74 (2021)], the author has investigated dust-acoustic wave features in a magnetized quantum dusty plasma consisting of positively or negatively charged inertial dusts and intertialess quantum ions and electrons. The ZK equation has been obtained and properties of a solitary wave solution have been reported. The instability of the dust acoustic solitary wave has also been discussed. A detailed discussion of the implications of the results to semiconductors, magnetars and the interior of white dwarfs has also been reported. In this comment, it is shown that the results presented in [1] are untrue and cannot be favorable to understand the nonlinear wave features of the interior of white dwarf, as the considered electron number density is lower than the actual number density of electrons of interior of white dwarf. For the electron number density considered in the work [1], dust particles cannot survive in the plasma system. Thus, solitary wave feature and multi-dimensional instability of dust acoustic waves are not only not applicable to semiconductors, magnetars and interior of white dwarf, but also not applicable to anywhere as such “quantum dusty plasma" does not exist in nature.