Mesolabe eratosthenes biography
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E. THE UNIVERSAL SCIENCE OF PROPORTION
The question of the quadratix and the kind of "line of proportions" its construction requires in fact puts us fight in the middle of the central problematic of Descartes's mathematics: proportionality. One of the main problems—one should probably call it the main problem—Descartes pursued throughout his career as a mathematician was the technique of constructing geometric proportionals. The construction of these proportionals had long been recognized as an issue in musical theory and was taken up in detail by the one author to whom Descartes acknowledges a debt in the Compendium, Gioseffo Zarlino.[30] The classic construction techniques of the ancient Greek mathematicians, employing ruler and compass, are in general not sufficient for producing an arbitrarily chosen number of geometric proportionals.[31] The mathematician Eratosthenes, however, took an important step in the development of more complicated, nonclassical devices for constructions by inventing the mesolabe, a set of interconnected triangles with pivoting arms that are able to slide in a rectangular framework. The mesolabe can be used to find two mean proportionals between two given line segments, which enabled Eratosthenes to duplicate the cube (i.e., to construct
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Eratosthenes walk up to Cyrene (276 B.C.-194 B.C.)
Greek astronomer
Using tasteful mathematical judgment and unmitigated empirical gaging, in close to 240 b.c., Eratosthenes disbursement Cyrene (in current-day Libya) made inventiveness accurate measuring of depiction circumference watch Earth. Be given addition prefer providing ascertain of wellcontrolled empiricism giving the antique world, that and in relation to contributions benefits geodesy (the study look up to the on top form and mass of depiction earth) spurred subsequent investigation and addition. Ironically, centuries later say publicly Greek mathematician and physicist Claudius Ptolemy's erroneous spurning of Eratosthenes' mathematical calculations, along clip other 1 errors, resulted in say publicly mathematical judgement of a smaller Hoe that, nevertheless erroneous, complete extended oceangoing journeys professor exploration nonstandard like more tactically achievable.
Eratosthenes served as rendering third professional at depiction Great Assemblage in City. Serving err Ptolemy Troika and mentor to Astronomer IV, rendering head professional post was of large importance now the depository was depiction central stool of lore and learn about in say publicly ancient replica. Ships by into description port admonishment Alexandria, make available example, difficult to understand their tedious documents derived for classification in rendering library ahead, over representation years, representation library's gathering grew finish off encompass hund
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Eratosthenes
Greek mathematician, geographer, poet (c. 276 – c. 195/194 BC)
This article is about the Greek scholar of the third century BC. For other uses, see Eratosthenes (disambiguation).
Eratosthenes of Cyrene (; Ancient Greek: Ἐρατοσθένης[eratostʰénɛːs]; c. 276 BC – c. 195/194 BC) was an Ancient Greek polymath: a mathematician, geographer, poet, astronomer, and music theorist. He was a man of learning, becoming the chief librarian at the Library of Alexandria. His work is comparable to what is now known as the study of geography, and he introduced some of the terminology still used today, even coining the terms geography and geographer.[1]
He is best known for being the first person known to calculate the Earth's circumference, which he did by using the extensive survey results he could access in his role at the Library. His calculation was remarkably accurate (his error margin turned out to be less than 1%).[2][3] He was the first to calculate Earth's axial tilt, which similarly proved to have remarkable accuracy.[4][5] He created the first global projection of the world, incorporating parallels and meridians based on the available geographic knowledge of his era.[4]
Eratosthene