Abū’l-‘Abbās al-Faḍl ibn Ḥātim al-Nairīzī ( ar, أبو العباس الفضل بن حاتم النيريزي, la, Anaritius, Nazirius, c. 865–922) was a Persian

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

and

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

from Nayriz, Fars Province,

Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...

. He flourished under

al-Mu'tadid Abū al-ʿAbbās Aḥmad ibn Ṭalḥa al-Muwaffaq ( ar, أبو العباس أحمد بن طلحة الموفق), 853/4 or 860/1 – 5 April 902, better known by his regnal name al-Muʿtaḍid bi-llāh ( ar, المعتضد بالله, link=no, ...

Caliph A caliphate or khilāfah ( ar, خِلَافَة, ) is an institution or public office under the leadership of an Islamic steward with the title of caliph (; ar, خَلِيفَة , ), a person considered a political-religious successor to th ...

from 892 to 902, and compiled astronomical tables, writing a book for al-Mu'tadid on atmospheric phenomena. Nayrizi wrote commentaries on

Ptolemy Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...

and

Euclid Euclid (; grc-gre, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the '' Elements'' treatise, which established the foundations of ...

. The latter were translated by

Gerard of Cremona Gerard of Cremona (Latin: ''Gerardus Cremonensis''; c. 1114 – 1187) was an Italian translator of scientific books from Arabic into Latin. He worked in Toledo, Kingdom of Castile and obtained the Arabic books in the libraries at Toledo. Some of ...

. Nairizi used the so-called umbra (versa), the equivalent to the tangent, as a genuine trigonometric line (but he was anticipated in this by al-Marwazi). He wrote a treatise on the spherical astrolabe, which is very elaborate and seems to be the best Persian work on the subject. It is divided into four books: #Historical and critical introduction. #Description of the spherical astrolabe; its superiority over plane

astrolabe An astrolabe ( grc, ἀστρολάβος ; ar, ٱلأَسْطُرلاب ; persian, ستاره‌یاب ) is an ancient astronomical instrument that was a handheld model of the universe. Its various functions also make it an elaborate inclin ...

s and all other astronomical instruments. #Applications. #Applications. He gave a proof of the

Pythagorean theorem In mathematics, the Pythagorean theorem or Pythagoras' theorem is a fundamental relation in Euclidean geometry between the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse (the side opposit ...

using the Pythagorean tiling.. Reprinted in . See also . Nelsen uses the "Annairizi" form of his name; for the identification of it with Anaritius, see ''Isis'', vol. 6
p. 515

Ibn al-Nadim Abū al-Faraj Muḥammad ibn Isḥāq al-Nadīm ( ar, ابو الفرج محمد بن إسحاق النديم), also ibn Abī Ya'qūb Isḥāq ibn Muḥammad ibn Isḥāq al-Warrāq, and commonly known by the ''nasab'' (patronymic) Ibn al-Nadīm ...

mentions Nayrizi as a distinguished astronomer with eight works by him listed in his book ''

al-Fihrist The ''Kitāb al-Fihrist'' ( ar, كتاب الفهرست) (''The Book Catalogue'') is a compendium of the knowledge and literature of tenth-century Islam compiled by Ibn Al-Nadim (c.998). It references approx. 10,000 books and 2,000 authors.''The ...

''.

Notes

References

*H. Suter: Die Mathematiker und Astronomen der Araber (45, 1900) *Nachtrage (164, 1902). *

Primary sources

''The (fragmentary) text of Nairizi's commentary on Euclid I. PDF scans from the edition of Codex Leidensis 399''
(Classical Arabic)

External links

* *
PDF version
Scientists who worked on qibla determination 9th-century Iranian mathematicians 10th-century Iranian mathematicians 860s births 922 deaths Year of birth uncertain Mathematicians from the Abbasid Caliphate Astronomers from the Abbasid Caliphate People from Fars Province 10th-century Iranian astronomers 9th-century Iranian astronomers {{Asia-mathematician-stub