D O C . 131 O B I T A R Y F O R W. . J L I S 233 198 . But in contrast with the latter, the former causes an asymmetrical broadening of the lines. Julius thus explained shifts which, ascribed to a Doppler effect, called for improbably large velocities varying from line to line. In the same way he explained why the shift toward the red observed in the center of the sun differs from that at the periphery. He believed that the entire observed displacement of lines toward the red had to be explained in this way, and, therefore, held the opinion that the shift required by the theory of relativity does not exist. I am not competent to render judgment on the reach of Julius’ ideas, but I believe that they deserve careful consideration, par- ticularly in the discussion of shifts in spectral lines. These few re- [6] marks will have served their purpose if they bring anew to the atten- tion of the profession the work of this clear-sighted, artistically fine- spirited man. N a t u u r k u n d ig L a bo r a t o r iu m d e r R i j k s -Un i v e r s i t e i t L e id e n December 14, 1925 [7] ublished in r p i al ur al 63 (1926) 196-198. Dated Leiden, 14 December 1925. ublished April 1926. [1]Julius had died on 25 April 1925. In October, Edwin B. Frost, the editor of r p i al ur al, had asked Einstein to write an obituary (see Abs. 167). e would translate it himself into English if submitted in German. [2]Einstein first met Julius in November 1911, when he was a candidate for a chair at the niversity of trecht (see Einstein to Julius, 1 and 11 November 1911 [Vol. 5, Docs. 302 and 304]). In August 1911, Einstein and Julius had entered upon a correspondence on the possibility of observing gravita tional redshift in the Fraunhofer lines of the solar spectrum. In later years Einstein regularly visited the Julius family in their home in trecht. [3] id , . 9 . [4]See, e.g., al 9 . [5]See au d r 9 . Its author was in fact Annie Scott Dill Russell Maunder (1868-1947), a “computer at the Royal Greenwich Observatory from 1891 to 1895 and the wife (and collaborator) of the astronomer Edward Walter Maunder (1851-1928). In her paper, one of only a few sole authored papers she published, since women could not join professional societies, she claimed that more sun spots are observed on the eastern hemisphere of the Sun than the west. This unlikely result was e plained by Julius as being due to differences in rotation at different depths in the solar atmosphere, creating favorable lines of sight for viewing sunspots from the Earth. [6]See, e.g., uliu 9 , which is based on an analysis of the observations of solar spectral lines. The outcome is that “we are forced to conclude that the gravitational displacement does not e ist. [7]After Julius’s death, a manuscript for a comprehensive book on his theory of the solar atmo sphere was finished by his student Marcel Minnaert ( uliu 9 , but interest in Julius’s ideas dwin dled rapidly. See also l 99 for a critical discussion of Julius’s work.
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