QÄá¸Ä« ZÄda al-RÅ«mÄ«
Salah ad-Din Musa Pasha, known as Salah ad -Din Musa ibn Mahmud ibn Muhammad al -ma ʿ ruf bi -Qadi Zada al- Rumi, (* 1364 in Bursa, Ottoman Empire, † 1436 in Samarkand ) was a Turkish mathematician and astronomer at the madrasah and the Ulugh Beg observatory in Samarkand.
Biography
As his nickname is, he is the son of a judge ( Qadi ) from the former Eastern Roman Empire (ar - Rumi ). His birth city of Bursa was until 1368 the capital of the Ottoman Empire. His father, Mahmoud Effendi, was entrusted alongside the judge directing the Madrasa of Kapıcılar in Bursa, where Qadi Zada was a first basic training.
He then continued his education at the scholar al - Farní (1350-1431) in Basra, in Iraq today, gone. He made a name for himself through the Risālatun fī - l - Hisab, a treatise on arithmetic and algebra, which he wrote in Basra in 1383. In al - Farnīs advice, he continued his studies after 1407 in the city of Herat in the province of Khorasan, then later in Bukhara and Samarkand, continued. 1410 he met in Samarkand the Timurid prince Ulugh Beg, who made him his teacher. During this period he wrote a number of commentaries on mathematics and astronomy, which were originally intended for training Ulugh Beg. Below is a commentary on the comprehensive treatise only 20 pages of Shams ad - Dīn Muḥammad ibn al -Ashraf al - Husaini as- Samarqandi over 35 theses of Euclid.
Ulugh Beg in 1420 appointed him as one of 70 scholars to the newly founded Madrasah in Samarkand. Together with the astronomer Al- Kasi he constructed the observatory Gurchanī Zīǧ, where he became manager after the death of Al- Kazis. The work at the observatory were summarized in the star catalog Zīǧ - ī - Sultani.
His most original mathematical work is the Risālatu - l - ǧaib (Treatise on the sinus ), in which he calculated the sine of 1 ° to 16 decimal places. At the same time came Ulugh Beg and / or Al - Kasi on a different path to the same result (see Ulugh Beg madrasah ).
Narrated still an incomplete commentary on the astronomical works of the at- Tusi and a treatise on mathematical methods for determining the qibla, the direction of prayer to Mecca.