6 2 D O C U M E N T 3 0 M A Y 1 9 2 3 Die elektromagnetischen Feldgesetze lauten bei Ihnen ja genau so wie in meiner Theorie! Auch Sie haben ein absolut normiertes Potential , und der Feldstrom hängt mit ihm nach der Gleichung zusammen Im ganzen freue ich mich natürlich, daß ich Ihnen jetzt auf den gleichen rein spe- kulativen Pfaden begegne, gegen die Sie früher immer protestierten.[5] Freilich— wer weiß, ob auf diesem Wege eine zwingende Entscheidung zu erzielen ist! Mit den besten Grüßen Ihr treu ergebener Anhänger und Gegner H. Weyl. ALS. [24 074]. There are calculations on the back of the document (see Doc. 32). [1]Weyl (1885–1955) was Professor of Mathematics at the Eidgenössische Technische Hochschule in Zurich. [2]A paper by Weyl with the same title as Einstein 1923e (Vol. 13, Doc. 425), “On the General The- ory of Relativity” (“Zur allgemeinen Relativitätstheorie,” Weyl 1923a), was received by the Physika- lische Zeitschrift on 17 April 1923 and issued on 1 June 1923. It discusses both the question of gravitational redshift and the problem of cosmological models, but does not contain a discussion of the subject raised in this letter. [3]Apparently unpublished. But Weyl did react to the approach of Eddington 1921 briefly in Weyl 1921, p. 480, and in Weyl 1923a, pp. 323–324 (Appendix IV). [4]In eq. (5a) of Einstein 1923e (Vol. 13, Doc. 425), , where is the (asym- metric) Ricci tensor obtained from the symmetric affine connection, and and its symmetric and antisymmetric parts, respectively. λ is a large numerical factor introduced to make possible an interpretation of as metric tensor of “human” dimensions. The antisymmetric part is inter- preted as the electromagnetic field tensor. In contrast to Einstein’s approach, Weyl’s Ansatz here is designed to study weak electromagnetic fields. [5]There was a long-standing disagreement between Einstein and Weyl about the latter’s proposal of a unified field theory based on the concept of a variable length connection. More generally, both in print and in their correspondence, Einstein had repeatedly criticized Weyl’s understanding of the “relationship between the propositions of theoretical physics and reality” (“des Verhältnisses, welches zwischen den Aussagen der Physik und der Wirklichkeit besteht” Einstein 1918h [Vol. 7, Doc. 10]). ϕk λ2ik 6 --------- = ik 6 λ2 -----ϕk g.— = λ2Rkl gkl ϕkl += Rkl gkl ϕkl gkl ϕkl