2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/27281In a recent PRL, Gonze et al claim that the density functional theory in Hohenberg-Kohn formulation is not valid for crystalline solids in a homogenious electric field. They introduce another theory, density-and-polarization functional theory, which has to substitute the DFT in the calculations of the long-wave dielectric response. We show that the theorem proven by Gonzo et al holds in addition to, and not instead of, the Hohenberg-Kohn theorem.1 page, revtex, no figuresCondensed MatterMaterials Sciencetext