6 2 8 D O C . 4 3 4 C A L C U L A T I O N 434. Calculation [Berlin, between 14 March and 19 March 1929][1] . AD. [73 287]. On the verso of Abs. 1038. Sotheby’s Auction Catalog 3, 1986, lot 190, p. 90. [1] Dated by the date of Abs. 935 and 1038, and by the fact that Einstein also sent a copy of Doc. 435 enclosed with the latter. hg hg , + – hg – hg , h – hg , x hg hg + = hg , hg | + hg , hg | + 0 g , g g h + + = 0 g , g g h + + = h g g – g – + g h ( – g g ) = 0 +