It is quite simple, as it pertains to the matter phase as being of solid, gaseous, liquid, or supercritical (sometimes plasma) state. As with any attempt at d

It is quite simple, as it pertains to the matter phase as being of solid, gaseous, liquid, or supercritical (sometimes plasma) state. As with any attempt at delta measurement of energy, you need that starting reference point being used by your test instrument and that method of measurement is likely not to be the same one for different matter phases: Heisenburg uncertainty principle comes to mind here.