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. The Zij al-Sindhind was the first astronomical table ever introduced in the Muslim World. 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. He also wrote a commentary on "Kitāb al-ğabr wa-l-muqābala" and helped prove the works of al-Khwarizmi. The decimal point notation to the Arabic numerals was introduced by Sind ibn Ali.
Al-Akhtal al-Taghlibi Ghiyath ibn Ghawth al-Taghlibi, commonly known as al-Akhtal (  640 710), was one of the most famous Arab poets of the Umayyad period. He belonged to the Banu Taghlib tribe of Upper Mesopotamia, and was, like his fellow-tribesmen, a Christian, enjoying the freedom of his religion.