WEYL, HERMANN (+) ROLAND EÖTVÖS.

Eine Neue Erweiterung der Relativitätstheorie [Weyl] (+) Experimenteller Nachweis der Schwereänderung, die ein auf normal geformter Erdoberfläche in östlicher oder westlicker Richtung bewegter Körper durch diese Bewegung erleidet [Eötvös].

Leipzig, Ambrosius Barth, 1919. 8vo. In contemporary half cloth with gilt lettering to spine. In "Annalen der Physik", Vierte Folge, Band 59. Entire volume offered. Hinges weak a library labels pasted on the pasted down front free end paper. Stamp to title page, othrewise a fine copy. Pp. 101-133; Pp. 743-752. [Entire volume: VII, (1), 760 pp.].

First printing of WEYL ambitious paper in which he used the Stoney units, named after the Irish physicist George Johnstone Stoney, to unify quantum processes and gravity thereby seeking to create a "Unified Field Theory". The paper appears to have inspired Dirac's fascination with the large number hypothesis.

Also contain in this volume is the first appearance of EÖTVÖS' important paper in which he explains the eastward deflection of falling objects. In the paper, he also describes a device with which the effect can be demonstrated experimentally.
The Eötvös effect is the change in perceived gravitational force caused by the change in centrifugal acceleration resulting from eastbound or westbound velocity. When moving eastbound, the object's angular velocity is increased (in addition to the earth's rotation), and thus the centrifugal force also increases, causing a perceived reduction in gravitational force.
This phenomenon had been observed in the early 20th century on research ships on which gravity was measured; they noticed that measurements of g yielded smaller values when the ship went eastward, and larger ones when they went westward. These observations are mentioned by Eötvös in a paper in which he provides the explanation of the effect.

Order-nr.: 50281