also studied the arithmetic of elliptic curves. He classified them up to isomorphism, not only over C, but also over Q. Next he studied what in modern terminology would be the subgroup of rational torsion points on an elliptic curve over Q: he proved that certain groups were realizable and that others were not. He essentially formulated the torsion conjecture for elliptic curves over the rational numbers, providing a complete list of possibilities should be, which was formulated independently by Andrew Ogg about 60 years later and finally proved by Barry Mazur in 1973. References Biographic and general references . An ample biographical paper of nearly 40 pages, an earlier version of which was published as . References describing his scientific contributions . For a freely downloadable offprint from the web site of one of the two authors, see here. External links . The web site of a scientific meeting in Bologna, honouring the memory of Beppo Levi. (in Italian). Available from the Edizione Nazionale Mathematica Italiana. 1875 births 1961 deaths Scientists from Turin People from Rosario, Santa Fe Argentine Sephardi Jews Argentine mathematicians 19th-century Italian mathematicians 20th-century Italian mathematicians 20th-century Italian Jews Italian emigrants to Argentina Jewish scientists Italian Sephardi Jews University of Turin alumni Academic staff of the University of Turin Academic staff of the Università Cattolica del Sacro Cuore Academic staff of the University of Cagliari Academic staff of the University of Parma Academic staff of the University of Bologna National University of Rosario faculty