## 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 in which the existence of photons might lead to observable derivations from the classical picture" (Pais, p. 413). In 1922, after six years of experimental and theoretical work, Arthur H. Compton discovered what came to be called the Compton effect; Peter Debye also discovered this independently and virtually simultaneously.

Pauli then used Compton & Deby’s work to extend Einstein's 1917 work to the case of radiation in equilibrium with free electrons (Pais, 414). "Pauli examined the requirements of detailed balance under Lorentz transformations and found that scattering of light by free electrons must include a term of a form which we would now call stimulated emission . . . Einstein and Ehrenfest then showed that Pauli's results could be obtained by an extension of [Einstein's] 1917 paper with the unnecessary specialization to discrete energy levels removed . . .

“The core of Einstein's argument is that the scattering process should be broken into two parts: the absorption of energy from radiation of frequency 1 and the emission of energy as radiation of frequency 2" Lewis, "Einstein's derivation of Planck's radiation law," AJP, 1973, 38-44.

Weil, Einstein Bibliography, 138; Pais, Subtle is the Lord, 21, 413; Lewis, "Einstein's derivation of Planck's radiation law," AJP, 1973, 38-44; Calaprice, Einstein Almanac 121.

ALSO INCLUDED IN VOLUME 19 ARE PAPERS BY: Hertz, Meitner, Lande, Hertzfeld, Joos, Kossel, Lande, Sommerfeld, Seeliger, Wentzel, Raschevsky, Ebert, and Toussaint among many others.

ALSO INCLUDED IN VOLUME 20 ARE PAPERS BY: Pauli, Ornstein, Raschevsky, Bothe, Walter, Hermann, and Przibram among many others. Item #1650

CONDITION: Berlin: Julius Springer. Volumes 19 & 20 bound as one. [iv], 415pp + [v], 426pp. NOT EX-LIBRARY. Solidly and cleanly bound in blue cloth, gilt-lettered at the spine. Bright and clean inside and out. Very good + condition.

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Price:
$195.00
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