Who did more ring theory, Cahit Arf or Sind ibn Ali?
Sind ibn Ali: He is known to have translated and modified the Zij al-Sindhind. Sind ibn Ali:  The Zij al-Sindhind was the first astronomical table ever introduced in the Muslim World. Sind ibn Ali:  As a mathematician Sind ibn ʿAlī was a colleague of al-Khwarizmi and worked closely with Yaqūb ibn Tāriq together they calculated the diameter of the Earth and other astronomical bodies. Sind ibn Ali:  The decimal point notation to the Arabic numerals was introduced by Sind ibn Ali.
i don't know