Johann Georg von Soldner

Johann Georg von Soldner (* July 16, 1776 Georgenhof with wet cheeks, † May 13, 1833 in Munich- Bogenhausen ) was a German physicist, mathematician, astronomer and surveyor.

Life

He was born the son of a farmer Johann Andreas Soldner on 16 July 1776 at the Georgenhof wet cheeks in the Middle Franconian district of Ansbach. He received two years of teaching at the Feuchtwanger Latin School. It showed in his early mathematical talent: with homemade instruments he measured the lands of his father and nights he studied math textbooks and maps. Since he had never attended a high school, he began in 1796 with private study of languages ​​and mathematics in Ansbach. 1797 the then Prussian citizen to Berlin, where he was employed by the astronomer Johann Elert Bode at the Berlin Observatory as a geometer, and operation is at astronomical and geodetic studies. 1804-1806 he headed the survey of the Principality of Ansbach. In 1808, he was brought by Joseph Utzschneider to Munich and set as trigonometers the newly established control surveying Commission. For his contributions to the theoretical foundations for the Bavarian Land Surveying him later the personal title of nobility was conferred. In 1815 he was appointed court astronomer. After the astronomer and mathematician Charles Felix of Seyffer (1762-1822) due to " astronomical inaction " regarding the redeployment of the observatory in arch bei München 1813 excused from his duties and the physicist and mathematician Anselm Ellinger ( 1758-1816 ) appointed as its representative was Soldner took over in November 1815 after Seyffers release the successor and was appointed on 1 April 1816 Observatories director. 1816-1818 then was composed of Utzschneider, Georg Friedrich von Reichenbach and Joseph von Fraunhofer built the new observatory on a hill east of the village Bogenhausen. From 1828 on, Soldner could not do full justice to his duties due to a liver ailment. Therefore, his young assistant Johann Lamont led under his supervision the affairs of the observatory. Soldner was on the Bogenhausener cemetery on the west side of the church of St. George buried ( grave of honor ).

Work

In Soldner including the Soldner coordinate system goes back, which was used in many parts of Germany until the 20th century, in the State of Berlin even in the 21st century. He has dealt with the logarithmic integral and to 1809 the work Théorie et tables d' une nouvelle fonction transcendante written mathematically. Soldner was the first of γ is the Euler constant by Lorenzo Mascheroni (1790 ) = 0.57721 ... is calculated to 22 decimal places right (1809 ).

1804 (written 1801), one of his works was published, in which he concluded due to Newton's corpuscular theory of light, that light would be deflected by the heavenly bodies, taking in the context of the Newtonian law of gravitation using the mass- independent classical equations of motion the value of 0.84 arcseconds received. Soldner wrote:

" So when passing a Lichtstral to a world body, he is compelled by the same attraction, rather than to go away in the straight direction, to describe a hyperbola whose concave side is directed toward the attracting body. [ ... ] If you are in the formula for tang ω the acceleration of gravity on the surface of the Sun substituted and assumes the radius of this body for the unit, one finds ω = 0.84 ". If one could observe the fixed stars very close to the Sun, it would probably have to take this into account. Since this is well known, does not happen, so the perturbation by the Sun is negligible. "

In his first work on the general theory of relativity ( 1908.1911 ) Albert Einstein received the same value for the distraction. However, this work proved with the development of the theory as inadequate and in 1916 finally came to Einstein to a deflection of 1.75 ", or about twice as large as Sold agent value. Thereupon led 1921 Einstein and relativity opponent Philipp Lenard a Neuabdruck of wages agent work in the annals of physics, with the intention of undermining the priority Einstein to present an alternative to ART and to point out a possible plagiarism Einstein. However, this was and the other rejected the same instance of Max von Laue, because pay former value of a hand, half as large as Einstein, and because the foundations of the theories are completely different, so that a comparison between them gives no sense. modernity measurements confirm the Einstein value.

Honors

1803 he was in Berlin dissertation without the degree of Dr. phil. awarded. Since 1813 Soldner was a member of the Bavarian Academy of Sciences. In 1825 he was appointed a member of the Astronomical Society of London. Him the Knight's Cross of the Bavarian Order of Civil Merit (1825 ) and the Knight's Cross of the French Legion of Honour (1829 ) was awarded.

In damp cheeks Johann Georg von Soldner -Realschule wet cheeks is named after him. In Munich, since 1962 a monument commemorates Soldner. The Bavarian State Ministry of Finance provides for services to the Surveying since 2003 Soldner Medal.

Publications

• Soldner, J. G. von; ( Lenard, P.): close passes over the deflection of a light beam from its rectilinear motion by the attraction of a celestial body on which he, . In: Annals of Physics. 65, 1921, pp. 593-604. doi: 10.1002/andp.19213701503.

• JG v. Soldner: Théorie et tables d' une nouvelle fonction transcendante. J. Lindau, Munich 1809 (uni -goettingen.de ).