International Journal of Mathematics and Mathematical Sciences
Volume 5 (1982), Issue 4, Pages 675-690

Introductory remarks on complex multiplication

Harvey Cohn

Department of Mathematics, City College of New York, New York 10023, N.Y., USA

Received 24 May 1982

Copyright © 1982 Harvey Cohn. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Complex multiplication in its simplest form is a geometric tiling property. In its advanced form it is a unifying motivation of classical mathematics from elliptic integrals to number theory; and it is still of active interest. This interrelation is explored in an introductory expository fashion with emphasis on a central historical problem, the modular equation between j(z) and j(2z).