%0 Journal Article
%A Trachenko, K.
%A Monserrat, B.
%A Pickard, C. J.
%A Brazhkin, V. V.
%T Speed of sound from fundamental physical constants
%D 2020
%R 10.1126/sciadv.abc8662
%J Science Advances
%P eabc8662
%V 6
%N 41
%X Two dimensionless fundamental physical constants, the fine structure constant α and the proton-to-electron mass ratio mpme, are attributed a particular importance from the point of view of nuclear synthesis, formation of heavy elements, planets, and life-supporting structures. Here, we show that a combination of these two constants results in a new dimensionless constant that provides the upper bound for the speed of sound in condensed phases, vu. We find that vuc=α(me2mp)12, where c is the speed of light in vacuum. We support this result by a large set of experimental data and first-principles computations for atomic hydrogen. Our result expands the current understanding of how fundamental constants can impose new bounds on important physical properties.
%U https://advances.sciencemag.org/content/advances/6/41/eabc8662.full.pdf