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Al-Hassan Ibn Al-Haytham
Ḥasan Ibn al-Haytham, Latinized as Alhazen (; full name ; ), was a medieval mathematician, astronomer, and physicist of the Islamic Golden Age from present-day Iraq.For the description of his main fields, see e.g. ("He is one of the principal Arab mathematicians and, without any doubt, the best physicist.") , ("Ibn al-Ḥaytam was an eminent eleventh-century Arab optician, geometer, arithmetician, algebraist, astronomer, and engineer."), ("Ibn al-Haytham (d. 1039), known in the West as Alhazan, was a leading Arab mathematician, astronomer, and physicist. His optical compendium, Kitab al-Manazir, is the greatest medieval work on optics.") Referred to as "the father of modern optics", he made significant contributions to the principles of optics and visual perception in particular. His most influential work is titled '' Kitāb al-Manāẓir'' (Arabic: , "Book of Optics"), written during 1011–1021, which survived in a Latin edition. Ibn al-Haytham was an early propo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Islamic Calendar
The Hijri calendar ( ar, ٱلتَّقْوِيم ٱلْهِجْرِيّ, translit=al-taqwīm al-hijrī), also known in English as the Muslim calendar and Islamic calendar, is a lunar calendar consisting of 12 lunar months in a year of 354 or 355 days. It is used to determine the proper days of Islamic holidays and rituals, such as the Ramadan, annual fasting and the annual season for the Hajj, great pilgrimage. In almost all countries where the predominant religion is Islam, the civil calendar is the Gregorian calendar, with Assyrian calendar, Syriac month-names used in the Arabic names of calendar months#Levant and Mesopotamia, Levant and Mesopotamia (Iraq, Syria, Jordan, Lebanon and State of Palestine, Palestine) but the religious calendar is the Hijri one. This calendar enumerates the Hijri era, whose Epoch (reference date), epoch was established as the Islamic New Year in 622 Common Era, CE. During that year, Muhammad and his followers migrated from Mecca to Medina and es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abū Sahl Al-Qūhī
(; fa, ابوسهل بیژن کوهی ''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. Al-Qūhī was the leader of the astronomers working in 988 AD 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 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analysis
Analysis ( : analyses) is the process of breaking a complex topic or substance into smaller parts in order to gain a better understanding of it. The technique has been applied in the study of mathematics and logic since before Aristotle (384–322 B.C.), though ''analysis'' as a formal concept is a relatively recent development. The word comes from the Ancient Greek ἀνάλυσις (''analysis'', "a breaking-up" or "an untying;" from ''ana-'' "up, throughout" and ''lysis'' "a loosening"). From it also comes the word's plural, ''analyses''. As a formal concept, the method has variously been ascribed to Alhazen, René Descartes (''Discourse on the Method''), and Galileo Galilei. It has also been ascribed to Isaac Newton, in the form of a practical method of physical discovery (which he did not name). The converse of analysis is synthesis: putting the pieces back together again in new or different whole. Applications Science The field of chemistry uses analysis in thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alhazen's Problem
Alhazen's problem, also known as Alhazen's billiard problem, is a mathematical problem in geometrical optics first formulated by Ptolemy in 150 AD. It is named for the 11th-century Arab mathematician Alhazen (''Ibn al-Haytham'') who presented a geometric solution in his '' Book of Optics''. The algebraic solution involves quartic equations and was found in 1965 by . Geometric formulation The problem comprises drawing lines from two points, meeting at a third point on the circumference of a circle and making equal angles with the normal at that point (specular reflection). Thus, its main application in optics is to solve the problem, "Find the point on a spherical convex mirror at which a ray of light coming from a given point must strike in order to be reflected to another point." This leads to an equation of the fourth degree. ( Alhazen himself never used this algebraic rewriting of the problem) Alhazen's solution Ibn al-Haytham solved the problem using conic sections and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doubts Concerning Ptolemy
Doubt is a mental state in which the mind remains suspended between two or more contradictory propositions, unable to be certain of any of them. Doubt on an emotional level is indecision between belief and disbelief. It may involve uncertainty, distrust or lack of conviction on certain facts, actions, motives, or decisions. Doubt can result in delaying or rejecting relevant action out of concern for mistakes or missed opportunities. Psychology Partial or intermittent negative reinforcement can create an effective climate of fear and doubt. Philosophy Descartes employed Cartesian doubt as a pre-eminent methodological tool in his fundamental philosophical investigations. Branches of philosophy like logic devote much effort to distinguish the dubious, the probable and the certain. Much of illogic rests on dubious assumptions, dubious data or dubious conclusions, with rhetoric, whitewashing, and deception playing their accustomed roles. Theology Doubt as a path towards (deepe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Book Of Optics
The ''Book of Optics'' ( ar, كتاب المناظر, Kitāb al-Manāẓir; la, De Aspectibus or ''Perspectiva''; it, Deli Aspecti) is a seven-volume treatise on optics and other fields of study composed by the medieval Arab scholar Ibn al-Haytham, known in the West as Alhazen or Alhacen (965–c. 1040 AD). The ''Book of Optics'' presented experimentally founded arguments against the widely held extramission theory of vision (as held by Euclid in his ''Optica''), and proposed the modern intromission theory, the now accepted model that vision takes place by light entering the eye.D. C. Lindberg (1976), ''Theories of Vision from al-Kindi to Kepler'', Chicago, Univ. of Chicago Press The book is also noted for its early use of the scientific method, its description of the camera obscura, and its formulation of Alhazen's problem. The book extensively affected the development of optics, physics and mathematics in Europe between the 13th and 17th centuries. Vision theory B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johannes Kepler
Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws of planetary motion, and his books ''Astronomia nova'', ''Harmonice Mundi'', and ''Epitome Astronomiae Copernicanae''. These works also provided one of the foundations for Newton's theory of universal gravitation. Kepler was a mathematics teacher at a seminary school in Graz, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to the astronomer Tycho Brahe in Prague, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He also taught mathematics in Linz, and was an adviser to General Wallenstein. Additionally, he did fundamental work in the field of optics, invented an improved version of the refracting (or Keplerian) telescope, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roger Bacon
Roger Bacon (; la, Rogerus or ', also '' Rogerus''; ), also known by the scholastic accolade ''Doctor Mirabilis'', was a medieval English philosopher and Franciscan friar who placed considerable emphasis on the study of nature through empiricism. In the early modern era, he was regarded as a wizard and particularly famed for the story of his mechanical or necromantic brazen head. He is sometimes credited (mainly since the 19th century) as one of the earliest European advocates of the modern scientific method, along with his teacher Robert Grosseteste. Bacon applied the empirical method of Ibn al-Haytham (Alhazen) to observations in texts attributed to Aristotle. Bacon discovered the importance of empirical testing when the results he obtained were different from those that would have been predicted by Aristotle. His linguistic work has been heralded for its early exposition of a universal grammar, and 21st-century re-evaluations emphasise that Bacon was essentially a medi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitello
Vitello ( pl, Witelon; german: Witelo; – 1280/1314) was a friar, theologian, natural philosopher and an important figure in the history of philosophy in Poland The history of philosophy in Poland parallels the evolution of philosophy in Europe in general. Overview Polish philosophy drew upon the broader currents of European philosophy, and in turn contributed to their growth. Some of the most momentous .... Name Vitello's name varies with some sources. In earlier publications he was quoted as Erazmus Ciolek Witelo, Erazm Ciołek, Vitellio and Vitulon. Today, he is usually referred to by his Latin name Vitello Thuringopolonis, often shortened to Vitello. Life Vitello's exact birth-name and birthplace are uncertain. He was most likely born around 1230 in Silesia, in the vicinity of Legnica. His mother came from a Polish knightly house, while his father was a Germans, German settler from Thuringia. He called himself, in Latin, "''Thuringorum et Polonorum filius''" — "a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Peckham
John Peckham (c. 1230 – 8 December 1292) was Archbishop of Canterbury in the years 1279–1292. He was a native of Sussex who was educated at Lewes Priory and became a Friar Minor about 1250. He studied at the University of Paris under Bonaventure, where he would later teach theology. From his teaching, he came into conflict with Thomas Aquinas, with whom he debated on two occasions. Known as a conservative theologian, he opposed Aquinas' views on the nature of the soul. Peckham also studied optics and astronomy, and his studies in those subjects were particularly influenced by Roger Bacon and Alhazen. In around 1270, Peckham returned to England, where he taught at the University of Oxford, and was elected the provincial minister of England (Minoriten) in 1275. After a brief stint in Rome, he was appointed Archbishop of Canterbury in 1279. His time as archbishop was marked by efforts to improve discipline in the clergy as well as reorganize the estates of his see. Plura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Al-Khazini
Abū al-Fath Abd al-Rahman Mansūr al-Khāzini or simply al-Khāzini (, flourished 1115–1130) was an Iranian astronomer of Greek origin from Seljuk Persia. His astronomical tables written under the patronage of Sultan Sanjar (', 1115) is considered to be one of the major works in mathematical astronomy of the medieval period. Montelle, C. (2011). The ‘Well-Known Calendars’: Al-Khāzinī’s Description of Significant Chronological Systems for Medieval Mathematical Astronomy in Arabic. In Steele J. (Ed.), Calendars and Years II: Astronomy and Time in the Ancient and Medieval World (pp. 107-126). Oxford; Oakville: Oxbow Books. He provided the positions of fixed stars, and for oblique ascensions and time-equations for the latitude of Marv in which he was based.Meyerhof, M. (1948). 'Alī al-Bayhaqī's Tatimmat Siwān al-Hikma: A Biographical Work on Learned Men of the Islam. Osiris, 8, 122-217. He also wrote extensively on various calendrical systems and on the various manip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Averroes
Ibn Rushd ( ar, ; full name in ; 14 April 112611 December 1198), often Latinized as Averroes ( ), was an Andalusian polymath and jurist who wrote about many subjects, including philosophy, theology, medicine, astronomy, physics, psychology, mathematics, Islamic jurisprudence and law, and linguistics. The author of more than 100 books and treatises, his philosophical works include numerous commentaries on Aristotle, for which he was known in the Western world as ''The Commentator'' and ''Father of Rationalism''. Ibn Rushd also served as a chief judge and a court physician for the Almohad Caliphate. Averroes was a strong proponent of Aristotelianism; he attempted to restore what he considered the original teachings of Aristotle and opposed the Neoplatonist tendencies of earlier Muslim thinkers, such as Al-Farabi and Avicenna. He also defended the pursuit of philosophy against criticism by Ashari theologians such as Al-Ghazali. Averroes argued that philosophy was permissi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
