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
Etching of an ancient seal identified as Eratosthenes. Philipp Daniel Lippert [de], Dactyliothec, 1767.
Born
276 BC[note 1]
Cyrene (in modern Libya)
Died
194 BC (around age 82)[note 2]
Alexandria
Occupations
Scholar
Librarian
Poet
Inventor
Known for
Sieve of Eratosthenes
Founder of Geography
Eratosthenes of Cyrene (/ɛrəˈtɒsθəniːz/; Greek: Ἐρατοσθένης[eratostʰénɛːs]; c. 276 BC – c. 195/194 BC) was a 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.[1]
He is best known for being the first person known to calculate the circumference of the Earth, which he did by using the extensive survey results he could access in his role at the Library. His calculation was remarkably accurate.[2][3] He was also the first to calculate Earth's axial tilt, which has also proved to have remarkable accuracy.[4] He created the first global projection of the world, incorporating parallels and meridians based on the available geographic knowledge of his era.
Eratosthenes was the founder of scientific chronology;[5] he used Egyptian and Persian records to estimate the dates of the main events of the Trojan War, dating the sack of Troy to 1183 BC. In number theory, he introduced the sieve of Eratosthenes, an efficient method of identifying prime numbers and composite numbers.
He was a figure of influence in many fields who yearned to understand the complexities of the entire world.[6] His devotees nicknamed him Pentathlos after the Olympians who were well rounded competitors, for he had proven himself to be knowledgeable in every area of learning. Yet, according to an entry[7] in the Suda (a 10th-century encyclopedia), some critics scorned him, calling him Number 2 because he always came in second in all his endeavours.[8]
Cite error: There are <ref group=note> tags on this page, but the references will not show without a {{reflist|group=note}} template (see the help page).
^Cite error: The named reference roller was invoked but never defined (see the help page).
^Cite error: The named reference russo273277 was invoked but never defined (see the help page).
^"Imagine the Universe – The Earth".
^Cite error: The named reference cornell was invoked but never defined (see the help page).
^"Greek chronology". Britannica.
^Cite error: The named reference chambers was invoked but never defined (see the help page).
^Cite error: The named reference epsilon was invoked but never defined (see the help page).
^Cite error: The named reference asimov was invoked but never defined (see the help page).
Eratosthenes of Cyrene (/ɛrəˈtɒsθəniːz/; Greek: Ἐρατοσθένης [eratostʰénɛːs]; c. 276 BC – c. 195/194 BC) was a Greek polymath: a mathematician, geographer...
11 13 17 19 23 29 The sieve of Eratosthenes can be expressed in pseudocode, as follows: algorithm Sieve of Eratosthenes is input: an integer n > 1. output:...
defending himself against the charge that he murdered Eratosthenes, after he supposedly caught Eratosthenes committing adultery with his wife. Euphiletos defends...
The Eratosthenes Seamount or Eratosthenes Tablemount is a seamount in the Eastern Mediterranean, in the Levantine basin about 100 kilometres (60 mi) south...
Eratosthenes to find upper or lower bounds on the number of primes within a given set of integers. Because it is a simple extension of Eratosthenes'...
"Against Eratosthenes" is a speech by Lysias, one of the ten Attic orators. In the speech, Lysias accuses Eratosthenes, a member of the Thirty Tyrants...
Katasterismoi, "Constellations" or "Placings Among the Stars") is a lost work by Eratosthenes of Cyrene. It was a comprehensive compendium of astral mythology including...
period. The developments of Greek geography during this time, notably by Eratosthenes and Posidonius culminated in the Roman era, with Ptolemy's world map...
the geographer Eratosthenes of Cyrene (3rd century BC), called Pròs tèn Eratosthénous geographían ("Against the Geography of Eratosthenes"). It is known...
generated by a certain "sieve". This sieve is similar to the Sieve of Eratosthenes that generates the primes, but it eliminates numbers based on their position...
Origins of many of the concepts in geography can be traced to Greek Eratosthenes of Cyrene, who may have coined the term "geographia" (c. 276 BC – c. 195/194...
Eratosthenes Point (Bulgarian: нос Ератостен, romanized: nos Eratosthenes, IPA: ['nɔs ɛrɐto'stɛn]) is the ice-covered, rock-tipped northwest entrance...
invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene, who composed his now-lost Geography at the Library of Alexandria...
Huainanzi, in the 2nd century BC, Chinese astronomers effectively inverted Eratosthenes' calculation of the curvature of the Earth to calculate the height of...
for finding primes. There are many prime sieves. The simple sieve of Eratosthenes (250s BCE), the sieve of Sundaram (1934), the still faster but more complicated...
geographer, Eratosthenes (c. 276 BC – c. 195 BC) and was fully described by the Greek geographer Strabo (64/63 BC – ca. AD 24). Per Eratosthenes' definition...
by Eratosthenes in about 240 BC. Estimates of the accuracy of Eratosthenes's measurement range from 0.5% to 17%. For both Aristotle and Eratosthenes, uncertainty...
According to Eusebius in the Praeparatio evangelica (Book XV, Chapter 53), Eratosthenes found the distance to the Sun to be "σταδιων μυριαδας τετρακοσιας και...
legendary Trojan War, given by chief librarian of the Library of Alexandria Eratosthenes, among others. 1547 – Battle of Mühlberg. Duke of Alba, commanding Spanish-Imperial...
181–2 [= Eratosthenes, Catasterismi 13 (Hard 2015, p. 44; Olivieri, p. 17)]; Musaeus apud Hyginus, De Astronomica 2.13.6. According to Eratosthenes, Musaeus...
displaying wikidata descriptions as a fallback, a concept in group theory Eratosthenes, who calculated the diameter of the Earth around 240 BC. Graph or network...
ποταμός; c.f. Duane W. Roller, Eratosthenes' Geography, Princeton University Press, 2010, ISBN 978-0-691-14267-8, Eratosthenes (24 January 2010). p. 57. Princeton...
librarian, Eratosthenes of Cyrene (lived c. 280–c. 194 BC), is best known today for his scientific works, but he was also a literary scholar. Eratosthenes' most...
Global Information