Berlin, Julius Springer, 1923. 8vo. Bound in contemporary half cloth with gilt lettering to spine. Library stamp to front free end paper and titel page. A heavy bump to lower part of boards. In "Zeitschrift für Physik", bd. 17. Fine and clean. Pp. 168-89. [Entire volume: IV, 424 pp.].
First printing of Lanczos important paper in which he clearified the nature of the Event Horizon of Black Hole that r = (pi*R)/2 in the De Sitter solution corresponds to an event horizon and not to a singularity.
Order-nr.: 48938