Erwin Finlay-Freundlich
Erwin Finlay -Freundlich (* May 29, 1885 in Wiesbaden- Biebrich, † July 24, 1964 in Wiesbaden ) was an astrophysicist and the brother of Herbert Finlay Freundlich.
Life and work
Freundlich was the son of a Scottish mother, Ellen Elizabeth Finlayson, and Friedrich Philipp Ernst -friendly, the director of an iron foundry in Wiesbaden- Biebrich. He received his Ph.D. in 1910 in Göttingen at Felix Klein about a problem of analytic function theory, and then became an assistant at the Berlin Observatory, where he was responsible for routine measurements.
1911, the young physicist published at the Charles University in Prague Albert Einstein a later version of the general theory of relativity: On the influence of gravity on the propagation of light ( Ann. Phys 35 (1911 ) 898. ). He said a deflection of light rays tangentially graze the edge of the sun, of only 0 " .85 arc seconds ahead. ( In the final version of 1915/6, the value increased to 1 " .75 by taking into account the curvature of space. ) His colleague, the astronomer Leo Wenzel Pollak, sought astronomers should observe this effect. All experienced astronomers saw no chance. Freundlich, who wanted to escape the stupid routine activities, accepted the challenge with enthusiasm. Thus began a long association with Einstein.
First he tried to determine the deflection of light rays in the gravitational field of the sun from old eclipse photo plates. This failed because the recordings for other goals were optimized. But by publishing the negative result in 1913, two years before the publication of the final version of general relativity, the ideas of the relatively unknown professor at the Charles University of Prague became known in German circles astronomers. With the eclipse of August 21, 1914 in Russia, he then wanted to provide the experimental evidence. The expedition was specifically prepared as of April 1914, and also performed but failed because of the outbreak of the First World War. Friendly were interned in Russia. Even with another solar eclipse expeditions until 1954, no satisfactory results could be provided, often prevented even the weather.
After returning to Germany, sat down very friendly for the construction of a solar observatory, which was built as Einstein Tower in Potsdam. The Cello Playing Friendly learned about the cellist Luise Maas whose husband, the architect Erich Mendelsohn know who built the Einstein Tower. Friendly later headed the observatory belonging to the Einstein -Institut, a part of the Astrophysical Observatory (AIP ). However, the predicted by the theory of general relativity effect of the red shift of spectral lines in the gravitational field of the sun could not be detected. In 1929 he led an eclipse expedition to Sumatra, including Walter Grotrian took part in the.
1933 had to leave Germany friendly, he fell by his Jewish paternal grandmother under § 3 of the "Professional Civil Service Law ," the " Aryan paragraph ".. Until 1937 he headed the Astronomical Institute of the University of Istanbul, where he lectured in Zusammrnarbeit with Wolfgang Gleißberg developed new textbooks and also a solar observatory built. Until 1939 he held a chair at the Charles University in Prague.
About Holland he came on the recommendation of Arthur Stanley Eddington to the University of St Andrews, where he built an observatory. From 1951 to 1959 he held the John Napier - chair of astronomy.
The measurements for the deflection of light at the edge of the sun during solar eclipses had confirmed the general theory of relativity, but there was a problem. The measured value of the deflection was slightly higher than the theoretical value of 1 " .75 Friendly tried all his life to determine the reason. doing so, he removed not only further and further from the generally accepted theories but fell among his colleagues also increasingly sidelined. way he suggested, for example in 1953 with Max Born, an alternative theory for the redshift of the galaxies. ( the temperature of the universe was doing in the range 1.9 to 6 K is calculated. ) Towards the end of his life, then radio astronomers confirmed the theoretical value.
After his retirement, he returned to Germany. He settled in his native city of Wiesbaden and taught as visiting professor at the Johannes Gutenberg University in Mainz.
He is the eponym of the lunar crater -friendly.
Family
In 1913 he married the Jewess Kate Hirschberg. The marriage remained childless, and after the death of his wife's sister they adopted their children Hans and Renate.
Publications (selection)
- Analytic functions with arbitrarily prescribed, infinite- petalled existence ranges, Dissertation, Göttingen, 1910
- About an attempt to examine the suspected by A. Einstein deflection of light in gravitational fields, Astronomische Nachrichten 193 (1913) 369
- The foundations of Einstein 's theory of gravitation. With a foreword by Albert Einstein, Berlin: Springer, 1916.
- The tower telescope of the Einstein Foundation Berlin: Julius Springer, 1927
- Harald von Klüber and Albert von Brunn: Further studies on the determination of the deflection of light in the gravitational field of the sun, Potsdam: [ astrophysics. Observatory, Einstein Inst. ], 1933. ( Annals of the Bosscha - Sterrenwacht, Lembang (Java) )
- Erwin Finlay -Freundlich About the redshift of the spectral lines and Max Born: Theoretical comments on Freundlich's formula for the stellar redshift - Göttingen: Cambridge University Press, 1953, pp. 96-108 ( News of the Academy of Sciences in Göttingen, born in 1953, no. 7)