The Ruby fluorescence scale measures this quantity in a device by exciting electrons within its transparent chamber. Post-perovskite is a phase with high values of this quantity in a type of magnesium silicate. In 2023, a paper claiming to have observed superconductivity at 294 Kelvin in nitrogen-doped lutetium hydride in an environment where this quantity is high was retracted due to allegations of faking data and self-plagiarism by its primary author, Rangas Dias. D-DIA and (*) diamond (10[1])anvil cells can be used to subject materials to high values of this quantity. Enthalpy is defined as internal energy plus volume times this quantity. (10[1])This quantity is proportional to temperature over volume according to the ideal gas law. Constant in isobaric processes, for 10 points, name this quantity with SI unit Pascal, defined as force per area. ■END■