Arnold Schönhage (1 December 1934, Lockhausen, now Bad Salzuflen, Free State of Lippe) is a mathematician and computer scientist and Professor Emeritus at Rheinische Friedrich-Wilhelms-Universität, Bonn. He was also professor in Tübingen and Konstanz. Schönhage now lives near Bonn, Germany.
Schönhage together with Volker Strassen developed the Schönhage–Strassen algorithm for fast integer multiplication that has a run-time of O(N log N log log N).
Schönhage designed and implemented together with Andreas F. W. Grotefeld and Ekkehart Vetter a multitape Turing machine, called TP, in software. The machine is programmed in TPAL, an assembler language. They implemented numerous numerical algorithms including the Schönhage–Strassen algorithm on this machine.