Beschreibung:

EINSTEIN, Albert (1879-1955) Collection of 9 important offprints relating to Einstein’s work on Unified Field Theory. 'Zu Kaluzas Theorie des Zusammenhanges von Gravitation und Elektrizität. Erste [-Zweite] Mitteilung‘ Offprint from: Sitzungsberichten der Presussichen Akademie der Wissenschaften, Phys.-Math. Klasse, VI. Berlin: 1927. Offprint of Einstein’s reaction to Theodor Kaluza’s work linking gravitation and electromagnetism using Einstein’s gravitation equations for 5 dimensions, instead of 4. BRL 170; Weil 156. 2 parts in 1 vol., quarto (255 x 184 mm). Original printed orange wrappers. – 'Riemann-Geometrie mit Aufrechterhaltung des Begriffes des Fernparallelismus.‘ Offprint from: Sitzungsberichten der Presussichen Akademie der Wissenschaften, Phys.-Math. Klasse, XVII. Berlin: 1928. ‘[A] purely mathematical paper, a rarity in Einstein's oeuvre, in which he invented distant parallelism (also called absolute parallelism or teleparallelism... The resulting geometry, a Riemannian geometry with torsion, was the one Einstein independently invented...’ (Pais Subtle is the Lord pp. 344-45). BRL 174; Weil 161. Quarto (255 x 184 mm). Original printed orange wrappers (fine copy). – 'Neue Möglichkeit für Einheitliche Theorie von Gravitation und Elektrizität.’ Offprint from: Sitzungsberichten der Presussichen Akademie der Wissenschaften, Phys.-Math. Klasse, XVIII. Berlin: 1928. ‘Using the geometry he invented in the "Riemann Geometrie" paper he proposed one week later to use the formula expressed in "Neue Möglichkeit" for unification’ (Pais Subtle is the Lord p.345). BRL 175; Weil 162. Quarto (255 x 184 mm). Original printed orange wrappers (vertical and horiztonal creasefolds). Provenance: Max Wehrli (1909-1998, Swiss literary scholar and Germanist; stamp on upper wrapper). Sold with a duplicate, identical in text excepting the publisher's adverts on the lower wrapper which are different and with dating suggesting a later variant of 1929. – 'Zur einheitlichen Feldtheorie.‘ Offprint from: Sitzungsberichten der Presussichen Akademie der Wissenschaften, Phys.-Math. Klasse, I. Berlin: 1929. First edition of one of Einstein's last important scientific works. ‘In 1928, [Einstein] embarked on a new approach to a unified field theory ... By early 1929 he had solved the main problems involved in writing down field equations for his unified field theory ... Einstein's new theory was hailed in the press as an outstanding scientific advance.’' Einstein sought to build a theory of ‘unified field’ which would be a generalization of his gravitational theory and would include all electromagnetic phenomena. BRL 183; Norman 700; Weil 165; cf. PMM 416. Quarto (255 x 184 mm). Original orange printed wrappers (slight discolouration along upper edges of wrappers, and some faint creasing). – 'Die Kompatibilität der Feldgleichungen in der einheitlichen Feldtheorie.‘Offprint from: Sitzungsberichten der Presussichen Akademie der Wissenschaften, Phys.-Math. Klasse, I. Berlin: 1930. Quarto (255 x 184 mm). Original orange printed wrappers (fine copy). BRL 195; Weil 169. – and Walter MAYER (1887-1948). 'Zwei strenge statische Losungen der Feldgleichungen der einheitlichen Feldtheorie.‘ Offprint from: Sitzungsberichten der Presussichen Akademie der Wissenschaften, Phys.-Math. Klasse, VI. Berlin: 1930. Quarto (255 x 184 mm). Original orange printed wrappers (top corner faintly creased, otherwise a fine copy). BRL 196; Weil 170. – and Walter MAYER (1887-1948). ‘Einheitliche Theorie von Gravitation und Elektrizitat.’ Offprint from: Offprint from: Sitzungsberichten der Presussichen Akademie der Wissenschaften, Phys.-Math. Klasse, XXV. Berlin: 1931. Offprint of Einstein’s description of five dimensions. In 1921, Kaluza proposed an alternative unified field theory in direct opposition to Weyl, by supposing the dimensionality of space-time be enlarged and formal geometry preserved. In this paper, Einstein, and his assistant Mayer, reject Weyl and Eddington’s theories, r