EINSTEIN, Albert (1879-1955). "Zur allgemeinen Relativitätstheorie. (Mit Nachtrag)" Offprint from Preussische Akademie der Wissenschaften, Sitzungsberichte, XLIV.XLVI. Berlin, 1915. [AND:] "Erklärung der Perihelbewegung des Merkur aus der allgemeinen Relativitätstheorie." Offprint from Preussische Akademie der Wissenschaften, Sitzungsberichte. XLVII. Berlin, 1915. [AND:] "Kosmologische Betrachtungen zur allgemeinen Relativitätstheorie." Offprint from Preussische Akademie der Wissenschaften, Sitzungsberichte. VI. Berlin, 1917.

First editions, offprint issues, of the first publication of Einstein's general theory of relativity in the form it is known today. The first two offprints contain the first three of the four lectures which Einstein presented to the plenary session of the Prussian Academy in November 1915 (November 4, 11 and 18). They give his new formulation of general relativity theory, explaining “that he had ‘completely lost confidence’ in the equations [he] proposed in October 1914... His answers were still not entirely right. There was still one flaw, a much smaller one, which he eliminated three weeks later. But the road lay open. He was lyrical. ‘No one who has really grasped it can escape the magic of this [new] theory’” (Pais). Very rare at auction.

In the third paper present here, Einstein introduces an entire field, general relativistic cosmology, and introduces a constant--termed the Cosmological Constant—to describe a universe that is ever expanding. Einstein would later reject this concept as the worst mistake of his life. Nevertheless, discoveries in recent decades agree that we live in a universe that will always expand, and at an ever-increasing rate. Boni 74, 75, 96; Weil 75, 76, 92.

Three volumes, octavo. Original orange printed wrappers (some minor soiling and creasing, pencil numbering and small erasures to each).