Joseph Ludwig Raabe

Origins and early life

Joseph Ludwig Raabe was born on 15 May 1801 in Brody, the great Jewish trading town of Austrian Galicia, the son of Wolf and Haja Raabe, in a poor Jewish family, and this fiche states plainly that in 1827, while a student at the Polytechnic Institute in Vienna, he was baptized a Catholic, a conversion that opened the academic career closed to Jews and that does not change the fact of his birth.

Work and career

He had worked as a private tutor from his teens to support himself, and studied mathematics in Vienna under Adam von Burg. In 1831 he moved to Zurich, taught at the cantonal gymnasium and became a lecturer at the new University of Zurich in 1833 and professor there in 1843; when the Federal Polytechnic, today's ETH Zurich, opened in 1855 he was one of its first professors of mathematics. His name survives in Raabe's test, published in 1832 in Crelle's Journal, a criterion for the convergence of infinite series that is sharper than d'Alembert's ratio test and is still taught in every analysis course, and in Raabe's integral formula for the gamma function.

He wrote textbooks on differential and integral calculus that trained a generation of Swiss engineers. He died in Zurich on 22 January 1859, after years of illness that had forced him to give up teaching.