English D'Alembert operator Cited by user SmartAssLevelPro on 03 Jan 2023 In special relativity, electromagnetism and wave theory, the d'Alembert operator (denoted by a box: .).
English Enthalpy Cited by user KH-1 on 08 Sep 2021 Enthalpy is a property of a thermodynamic system, and is defined as the sum of the system's internal energy and the product of its pressure and volume.