From Surf Wiki (app.surf) — the open knowledge base

Abu Sahl al-Quhi

10th century Persian mathematician, physicist and astronomer

Field	Value
name	Abu Sahl Wayjan ibn Rustam al-Quhi

image	Mesue. Watercolour. Wellcome V0006562.jpg
other_names	Abu Sahl Quhi
caption	Al Quhi's official
birth_date	940
birth_place	Amol, Abbasid Caliphate
death_date	1000
death_place	Baghdad, Abbasid Caliphate
era	Islamic Golden Age
(Buyid dynasty era)
main_interests	Astronomer, Mathematician
notable_ideas
major_works	Encyclopedia of Astronomy & Astrophysics

(Buyid dynasty era)

ar (ar; Abusahl Bijan-e Koohi) was a Persian mathematician, physicist and astronomer. He was from Kuh (or Quh), an area in Tabaristan, Amol, and flourished in Baghdad in the 10th century. He is considered one of the greatest geometers, with many mathematical and astronomical writings ascribed to him.

Engraving of al-Qūhī's perfect compass to draw conic sections

Al-Qūhī was the leader of the astronomers working in 988 at the observatory built by the Buwayhid amir Sharaf al-Dawla in Badhdad. He wrote a treatise on the astrolabe in which he solves a number of difficult geometric problems.

In mathematics he devoted his attention to those Archimedean and Apollonian problems leading to equations higher than the second degree. He solved some of them and discussed the conditions of solvability. For example, he was able to solve the problem of inscribing an equilateral pentagon into a square, resulting in a fourth degree equation. He also wrote a treatise on the "perfect compass", a compass with one leg of variable length that allows users to draw any conic section: straight lines, circles, ellipses, parabolas and hyperbolas. It is likely that al-Qūhī invented the device.

Like Aristotle, al-Qūhī proposed that the weight of bodies varies with their distance from the center of the Earth.

The correspondence between al-Qūhī and Abu Ishaq al-Sabi, a high civil servant interested in mathematics, has been preserved.

References

"The first steps for learning optics : Ibn Sahl's, Al-Khayam's and Young's works on refraction as typical examples". II.
[http://adsabs.harvard.edu/abs/2000eaa..bookE3410. al-Qūhī, Abu Sahl Wayjan ibn Rustam (c. 940-c. 1000)]
Suter, ''Die Mathematiker und Astronomen der Araber'' (75-76, 1900). In his treatise On Rising Times, he wrote that he had also investigated astronomy as well as centers of gravity and optics. His Perfect Compass, for example, represented a step beyond [[Ibn Sina]]’s pointwise constructions of conic sections and described an instrument al-Qūhī characterized as useful for drawing these sections on sundials and astrolabes.
Berggren, Len. (2007). "Kūhī: Abū Sahl Wījan ibn Rustam [Wustam] al-Kūhī [al-Qūhī]". Springer.
[[Jan Hogendijk]] (1984) "al-Kuhi's construction of an equilateral pentagon in a given square", ''Zeitschrift für Gesch. Arab.-Islam. Wiss.'' 1: 100-144; correction and addendum Volume 4, 1986/87, p.267
"Abu Sahl Waijan ibn Rustam al-Qūhī". MacTutor.
[[Jan Hogendijk]] (2008) "Two beautiful geometrical theorems by Abu Sahl Kuhi in a 17th century Dutch translation", ''Ta'rikh-e Elm: Iranian Journal for the History of Science'' 6: 1-36
Thomas de Vittori. "The Perfect Compass: Conics, Movement and Mathematics around the 10th century".
Rashed, Roshdi. (1996}} Reviews: Seyyed Hossein Nasr (1998) in ''Isis'' '''89''' (1) pp. 112-113 {{JSTOR). "Les Mathématiques Infinitésimales du IXe au XIe Siècle '''1''': Fondateurs et commentateurs: Banū Mūsā, Ibn Qurra, Ibn Sīnān, al-Khāzin, al-Qūhī, Ibn al-Samḥ, Ibn Hūd".
John Lennart Berggren, Hogendijk: ''The Fragments of Abu Sahl al-Kuhi's Lost Geometrical Works in the Writings of al-Sijzi'', in: C. Burnett, J.P. Hogendijk, K. Plofker, M. Yano (eds): ''Studies in the History of the Exact Sciences in Honour of [[David Pingree]]'', Leiden: Brill, 2003, pp. 605–665
Mohammed Abattouy (2002), "The Arabic Science of weights: A Report on an Ongoing Research Project", ''The Bulletin of the Royal Institute for Inter-Faith Studies'' '''4''', p. 109-130
Berggren: "The correspondence of Abu Sahl al-Kuhi and Abu Ishaq al-Sabi: a translation with commentaries", ''J. Hist. Arabic Sci.'', volume 7, 1983, pp. 39-124.
M. Steinschnieder, ''Lettere intorno ad Alcuhi a D. Bald''. Boncompagni (Roma, 1863)

Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

1000-deaths 10th-century-iranian-mathematicians people-from-amol 10th-century-iranian-astronomers astronomers-of-the-medieval-islamic-world scholars-under-the-buyid-dynasty 10th-century-people-from-the-abbasid-caliphate

Want to explore this topic further?

Ask Mako anything about Abu Sahl al-Quhi — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report