Jakob Rosanes (also Jacob; 16 August 1842 – 6 January 1922) was a German mathematician who worked on algebraic geometry and invariant theory. He was also a chess master.
School period
College/University
Gallery of Jacob Rosanes
Humboldt University of Berlin, Berlin, Germany
Jakob Rosanesom from 1860 until 1864 studied at the University of Berlin.
Gallery of Jacob Rosanes
University of Wrocław, Wrocław, Lower Silesian Voivodeship, Poland
From 1864 until 1865 Rosanes studied at the University of Breslau having taken the Ph.D. at the latter in 1865, lie remained there for the rest of his career.
University of Wrocław, Wrocław, Lower Silesian Voivodeship, Poland
From 1864 until 1865 Rosanes studied at the University of Breslau having taken the Ph.D. at the latter in 1865, lie remained there for the rest of his career.
Jakob Rosanes was a prominent Prussian mathematician. He is noted for his work regarding algebraic geometry and invariant theory.
Background
Ethnicity:
He was a Galician-born Jew from an old Sephardic family.
Jakob Rosanes was born on August 16, 1842, in Brody, Austria-Hungary (now Ukraine), the son of Leo Rosanes, a merchant. His maternal grandfather was Akiva Eger, an outstanding Talmudic scholar who, for the last twenty years of his life, was the rabbi of the city of Posen.
Education
From 1860 until 1865 Rosanes studied at the universities of Berlin and Breslau; having taken the Ph.D. at the latter in 1865, lie remained there for the rest of his career.
In 1870 Rosanes became Privatdozent, in 1873 professor extraordinarius, and in 1876 ordinary professor; he also served the university as its rector during the academic year 1903–1904.
Rosanes’ mathematical papers concerned the various questions of algebraic geometry and invariant theory that were current in the nineteenth century. One of his first papers, written with Moritz Pasch, discussed a problem on conies in closure-position. In 1870 he provided a demonstration that each plane Cremona transformation can be factored as a product of quadratic transformations, a theorem that M. Noether also proved independently at about the same time. Both demonstrations were, however, incomplete and were put into final form by G. Castelnuovo some thirty years later.
He retired from the university in 1911 and spent the rest of his life in Breslau.
Rosanes wrote on many aspects of algebraic geometry and invariant theory (particularly between 1870 and 1890) which were in fashion at that time.
Personality
Perhaps Rosanes' main interest outside mathematics was chess. He was able to beat even one of the leading players of his time Adolf Anderssen which he did in Breslau in 1862 (although he lost to him in the following year).
Quotes from others about the person
Richard Courant described Rosanes' lecturing as follows: "... he scribbled equations which his students never quite saw because as he wrote he hid them with his body and as he moved along he rubbed them out with his sponge."