|
Al-Mahani
Abu-Abdullah Muhammad ibn Īsa Māhānī (, flourished c. 860 and died c. 880) was a Persian mathematician and astronomer born in Mahan, (in today Kermān, Iran) and active in Baghdad, Abbasid Caliphate. His known mathematical works included his commentaries on Euclid's '' Elements'', Archimedes' '' On the Sphere and Cylinder'' and Menelaus' ''Sphaerica'',* Roshdi Rashed and Athanase Papadopoulos, 2017 as well as two independent treatises. He unsuccessfully tried to solve a problem posed by Archimedes of cutting a sphere into two volumes of a given ratio, which was later solved by 10th century mathematician Abū Ja'far al-Khāzin. His only known surviving work on astronomy was on the calculation of azimuths. He was also known to make astronomical observations, and claimed his estimates of the start times of three consecutive lunar eclipses were accurate to within half an hour. Biography Historians know little of Al-Mahani's life due to lack of sources. He was born in Mahan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mahan, Iran
Mahan () is a city in, and the capital of, Mahan District of Kerman County, Kerman province, Iran. History Mahan is well known for the tomb of the great Sufi leader Shah Ne'emat Ollah-e-Vali, as well as Shazdeh Garden (Prince Garden). The tomb of Shah Nur-eddin Nematollah Vali, poet, sage, Sufi and founder of an order of darvishes, has twin minarets covered with turquoise tiles from the bottom up to the cupola. The mausoleum was built by Ahmad Shah Kani; the rest of the building was constructed during the reigns of Shah Abbas I, Mohammad Shah Qajar and Nasser-al-Din Shah. Shah Nematallah Wali spent many years wandering through central Asia perfecting his spiritual gifts before finally settling at Mahan, twenty miles south-east of Kerman, where he passed the last twenty five years of his life. He died in 1431, having founded a Darvish order which continues to be an active spiritual force today. The central domed burial vault at Mahan, completed in 1437 was erected by A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Al-Fihrist
The () (''The Book Catalogue'') is a compendium of the knowledge and literature of tenth-century Islam compiled by Ibn al-Nadim (d. 998). It references approx. 10,000 books and 2,000 authors.''The Biographical Dictionary of the Society for the Diffusion of Useful Knowledge'', Volume 2, Numero 2, p. 782 A crucial source of medieval Arabic-Islamic literature, it preserves the names of authors, books and accounts otherwise entirely lost. is evidence of Ibn al-Nadim's thirst for knowledge among the sophisticated milieu of Baghdad's intellectual elite. As a record of civilisation transmitted through Muslim culture to the Western world, it provides unique classical material and links to other civilisations. Content The ''Fihrist'' indexes authors, together with biographical details and literary criticism. Ibn al-Nadim's interest ranges from religions, customs, sciences, with obscure facets of medieval Islamic history, works on superstition, magic, drama, poetry, satire and music fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spherical Law Of Cosines
In spherical trigonometry, the law of cosines (also called the cosine rule for sides) is a theorem relating the sides and angles of spherical triangles, analogous to the ordinary law of cosines from plane trigonometry. Given a unit sphere, a "spherical triangle" on the surface of the sphere is defined by the great circles connecting three points , and on the sphere (shown at right). If the lengths of these three sides are (from to (from to ), and (from to ), and the angle of the corner opposite is , then the (first) spherical law of cosines states:Romuald Ireneus 'Scibor-MarchockiSpherical trigonometry ''Elementary-Geometry Trigonometry'' web page (1997).W. Gellert, S. Gottwald, M. Hellwich, H. Kästner, and H. Küstner, ''The VNR Concise Encyclopedia of Mathematics'', 2nd ed., ch. 12 (Van Nostrand Reinhold: New York, 1989). \cos c = \cos a \cos b + \sin a \sin b \cos C\, Since this is a unit sphere, the lengths , and are simply equal to the angles (in radians) subte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrolabe
An astrolabe (; ; ) is an astronomy, astronomical list of astronomical instruments, instrument dating to ancient times. It serves as a star chart and Model#Physical model, physical model of the visible celestial sphere, half-dome of the sky. Its various functions also make it an elaborate inclinometer and an analog computer, analog calculation device capable of working out several kinds of problems in astronomy. In its simplest form it is a metal disc with a pattern of wires, cutouts, and perforations that allows a user to calculate astronomical positions precisely. It is able to measure the horizontal coordinate system, altitude above the horizon of a celestial body, day or night; it can be used to identify stars or planets, to determine local latitude given local time (and vice versa), to survey, or to triangulation, triangulate. It was used in classical antiquity, the Islamic Golden Age, the European Middle Ages and the Age of Discovery for all these purposes. The astrolabe, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjunction (astronomy)
In astronomy, a conjunction occurs when two astronomical objects or spacecraft appear to be close to each other in the sky. This means they have either the same right ascension or the same ecliptic longitude, usually as observed from Earth. When two objects always appear close to the ecliptic—such as two planets, the Moon and a planet, or the Sun and a planet—this fact implies an apparent close approach between the objects as seen in the sky. A related word, '' appulse'', is the minimum apparent separation in the sky of two astronomical objects. Conjunctions involve either two objects in the Solar System or one object in the Solar System and a more distant object, such as a star. A conjunction is an apparent phenomenon caused by the observer's perspective: the two objects involved are not actually close to one another in space. Conjunctions between two bright objects close to the ecliptic, such as two bright planets, can be seen with the naked eye. The astronomical symbol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conic Section
A conic section, conic or a quadratic curve is a curve obtained from a cone's surface intersecting a plane. The three types of conic section are the hyperbola, the parabola, and the ellipse; the circle is a special case of the ellipse, though it was sometimes considered a fourth type. The ancient Greek mathematicians studied conic sections, culminating around 200 BC with Apollonius of Perga's systematic work on their properties. The conic sections in the Euclidean plane have various distinguishing properties, many of which can be used as alternative definitions. One such property defines a non-circular conic to be the set of those points whose distances to some particular point, called a '' focus'', and some particular line, called a ''directrix'', are in a fixed ratio, called the ''eccentricity''. The type of conic is determined by the value of the eccentricity. In analytic geometry, a conic may be defined as a plane algebraic curve of degree 2; that is, as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omar Khayyam
Ghiyāth al-Dīn Abū al-Fatḥ ʿUmar ibn Ibrāhīm Nīshābūrī (18 May 1048 – 4 December 1131) (Persian language, Persian: غیاث الدین ابوالفتح عمر بن ابراهیم خیام نیشابورﻯ), commonly known as Omar Khayyam (), was a Persian poet and polymath, known for his contributions to Mathematics in medieval Islam, mathematics, Astronomy in the medieval Islamic world, astronomy, Iranian philosophy, philosophy, and Persian literature. He was born in Nishapur, Iran and lived during the Seljuk Empire, Seljuk era, around the time of the First Crusade. As a mathematician, he is most notable for his work on the classification and solution of cubic equations, where he provided a geometric formulation based on the intersection of conics. He also contributed to a deeper understanding of Euclid's parallel axiom. As an astronomer, he calculated the duration of the solar year with remarkable precision and accuracy, and designed the Jalali calendar, a solar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abu Nasr Mansur
Abū Naṣr Manṣūr ibn ʿAlī ibn ʿIrāq al-Jaʿdī (; c. 960 – 1036) was a Persian Muslim mathematician and astronomer. He is well known for his work with the spherical sine law.Bijli suggests that three mathematicians are in contention for the honor, Alkhujandi, Abdul-Wafa and Mansur, leaving out Nasiruddin Tusi. Bijli, Shah Muhammad and Delli, Idarah-i Adabiyāt-i (2004) ''Early Muslims and their contribution to science: ninth to fourteenth century'' Idarah-i Adabiyat-i Delli, Delhi, India, page 44, Abu Nasri Mansur was born in Gilan, Persia, to the ruling family of Khwarezm, the Afrighids. He was thus a prince within the political sphere. He was a student of Abu'l-Wafa and a teacher of and also an important colleague of the mathematician, Al-Biruni. Together, they were responsible for great discoveries in mathematics and dedicated many works to one another. Most of Abu Nasri's work focused on mathematics, but some of his writings were on astronomy. In mathemati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasir Al-Din Al-Tusi
Muḥammad ibn Muḥammad ibn al-Ḥasan al-Ṭūsī (1201 – 1274), also known as Naṣīr al-Dīn al-Ṭūsī (; ) or simply as (al-)Tusi, was a Persians, Persian polymath, architect, Early Islamic philosophy, philosopher, Islamic medicine, physician, Islamic science, scientist, and kalam, theologian. Nasir al-Din al-Tusi was a well published author, writing on subjects of math, engineering, prose, and mysticism. Additionally, al-Tusi made several scientific advancements. In astronomy, al-Tusi created very accurate tables of planetary motion, an updated planetary model, and critiques of Ptolemaic astronomy. He also made strides in logic, mathematics but especially trigonometry, biology, and chemistry. Nasir al-Din al-Tusi left behind a great legacy as well. Tusi is widely regarded as one of the greatest scientists of medieval Islam, since he is often considered the creator of trigonometry as a mathematical discipline in its own right. The Muslim scholar Ibn Khaldun (1332–1406) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ahmad Ibn Abi Said Al-Harawi
Ahmad () is an Arabic male given name common in most parts of the Muslim world. Other English spellings of the name include Ahmed. It is also used as a surname. Etymology The word derives from the root ( ḥ-m-d), from the Arabic (), from the verb (''ḥameda'', "to thank or to praise"), non-past participle (). Lexicology As an Arabic name, it has its origins in a Quranic prophecy attributed to Jesus in the Quran which most Islamic scholars concede is about Muhammad. It also shares the same roots as Mahmud, Muhammad, Hamed, and Hamad. In its transliteration, the name has one of the highest number of spelling variations in the world. Some Islamic traditions view the name Ahmad as another given name of Muhammad at birth by his mother, considered by Muslims to be the more esoteric name of Muhammad and central to understanding his nature. Over the centuries, some Islamic scholars have suggested the name's parallel is in the word 'Paraclete' from the Biblical text,"Isa", ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Line (geometry)
In geometry, a straight line, usually abbreviated line, is an infinitely long object with no width, depth, or curvature, an idealization of such physical objects as a straightedge, a taut string, or a ray (optics), ray of light. Lines are space (mathematics), spaces of dimension one, which may be Embedding, embedded in spaces of dimension two, three, or higher. The word ''line'' may also refer, in everyday life, to a line segment, which is a part of a line delimited by two Point (geometry), points (its ''endpoints''). Euclid's Elements, Euclid's ''Elements'' defines a straight line as a "breadthless length" that "lies evenly with respect to the points on itself", and introduced several postulates as basic unprovable properties on which the rest of geometry was established. ''Euclidean line'' and ''Euclidean geometry'' are terms introduced to avoid confusion with generalizations introduced since the end of the 19th century, such as Non-Euclidean geometry, non-Euclidean, Project ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadratic Irrational Number
In mathematics, a quadratic irrational number (also known as a quadratic irrational or quadratic surd) is an irrational number that is the solution to some quadratic equation with rational coefficients which is irreducible over the rational numbers. Since fractions in the coefficients of a quadratic equation can be cleared by multiplying both sides by their least common denominator, a quadratic irrational is an irrational root of some quadratic equation with integer coefficients. The quadratic irrational numbers, a subset of the complex numbers, are algebraic numbers of degree 2, and can therefore be expressed as :, for integers ; with , and non-zero, and with square-free. When is positive, we get real quadratic irrational numbers, while a negative gives complex quadratic irrational numbers which are not real numbers. This defines an injection from the quadratic irrationals to quadruples of integers, so their cardinality is at most countable; since on the other hand every ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
