HYDROGEN

The PT phase diagram of H has as much importance in physics as the PT phase diagram of He. Solid state H may exist in metallic states that might have very important quantum mechanical properties, for example. H sits at the top of the alkali metal family and all of the members of this family have been isolated as elemental metals. Nellis has discovered metallic H in gas gun, dynamic pressure experiments in about 1998. The volume of this metallic H is small, but large enough to be considered a bulk sample of matter. Ashcroft was a co-author on the Nellis discovery and provided the exotic theory on the metallic state of H. Ashcroft has done much to advance the understanding and importance of the PT phase diagram of H. Independently of Ashcroft and Nellis, Silvera has done a great deal of experimental work elucidating the phase diagram of H using static high pressure methods with the diamond anvil cell. Silvera et al. has provided independent evidence of metallic H in their static pressure work, in experiments after 2015. H is the most abundant element and it exists possibly in great volumes in the metallic state under gravitational pressure in gas giant planets like Jupiter etc. For these other reasons H and metallic H qualify, as much as He does, as Nobel Prize caliber subjects. Nellis and Ashcroft are the lead scientists in this area.