## Zur Quantentheorie des Strahlungsgleichgewichts Zeitschrift fur Physik Vol. 19 + 20, pp. 301-306, 1923. [ON THE QUANTUM THEORY OF THE RADIATIVE EQUILIBRIUM, Not ex-library]

Berlin: Vieweg und Springer, 1923. 1st Edition. This paper, “On the Quantum Theory of the Radiative Equilibrium” introduces the expression “negative irradiance” ("negative Einstrahlung") for the emission of a quantum by action of irradiance (Calaprice, 121). Following his work on general relativity in 1916, Einstein continued searching for new ways..... More