title: Comment on "Dynamic transition of supercritical hydrogen: Defining the boundary between interior and atmosphere in gas giants".
abstract: Trachenko et al. [Phys. Rev. E 89, 032126 (2014)] have argued for the existence of a "Frenkel line" in fluid hydrogen that separates "rigid" and "nonrigid" regimes in a supercritical region. On that basis, they proposed a criterion for locating the boundary between the interior and the atmosphere for gas giants. This Comment shows that the two methods they use to locate the transition between the rigid and nonrigid states are both questionable, which casts doubt on the claims in the paper.
authors: Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii Street, UA-79011 Lviv, Ukraine and Lviv Polytechnic National University, 79013 Lviv, Ukraine.
authors: Taras
authors: T
authors: Bryk