Jamshid al-Kashi: The Last Islamic Polymath (Also Me)

Jamshid al-Kashi, a brilliant scholar of the 14th and 15th centuries in Iran and Central Asia, made significant contributions to the fields of astronomy and mathematics. Born in 1380 in Kashan, Iran, during a period of political upheaval and cultural decline in the Islamic world, he secured patronage from Timurid rulers, notably Ulugh Beg, who welcomed him to his observatory and university in Samarkand.

Al-Kashi delved into the mysteries of the cosmos and the earth, conducting observations of eclipses, calculating celestial body sizes and distances, and innovating improvements for astronomical instruments. Notably, he authored the Khaqani Zij, which housed precise tables for sines, cosines, and planetary positions. He also penned a guide on the astrolabe, a tool for measuring celestial positions. Pioneering the use of decimal fractions and devising an algorithm for cubic equation roots, he demonstrated his mathematical prowess.

A prolific mathematician, Al-Kashi elevated algebra, geometry, trigonometry, and arithmetic. His comprehensive textbook, "The Key to Arithmetic," and his work "The Treatise on the Chord and Sine" significantly advanced the field. His calculation of pi to 16 decimal places using a polygon with 3 × 2^28 sides remains a notable achievement. Additionally, he unveiled the law of cosines, offering insights into triangle relationships. His exploration of Pascal's triangle, a numerical array with myriad combinatorial applications, further showcased his mathematical ingenuity.

Tragically, Al-Kashi met his end in 1429 in Samarkand, possibly at the behest of Ulugh Beg, envious of his renown and accomplishments. Nevertheless, he bequeathed a legacy of scientific excellence that left an indelible mark on subsequent scholars, both within the Islamic world and beyond. Arguably the final Islamic polymath, Al-Kashi embodied the inquisitive and creative spirit that defined the Golden Age of Islam.