Введение
Греческий математик (ок. 417 – ок. 369 до н. э.)
Theaetetus of Athens (,/θ//iː//ɪ/'/t//iː//t//ə//s/; Theaítētos; c. 417 – c. 369 BCE), possibly the son of Euphronius of the Athenian deme Sunium, was a Greek mathematician. His principal contributions were on irrational lengths, which was included in Book X of Euclid's Elements and proving that there are precisely five regular convex polyhedra. A friend of Socrates and Plato, he is the central character in Plato's eponymous Socratic dialogue. Theaetetus, like Plato, was a student of the Greek mathematician Theodorus of Cyrene. Cyrene was a prosperous Greek colony on the coast of North Africa, in what is now Libya, on the eastern end of the Gulf of Sidra. Theodorus had explored the theory of incommensurable quantities, and Theaetetus continued those studies with great enthusiasm; specifically, he classified various forms of irrational numbers according to the way they are expressed as square roots. This theory is presented in great detail in Book X of Euclid's Elements. Theaetetus was one of the few Greek mathematicians who was actually a native of Athens. Most Greek mathematicians of antiquity came from the numerous Greek cities scattered around the Ionian coast, the Black Sea and the whole Mediterranean basin. He evidently resembled Socrates in the snubness of his nose and bulging of his eyes. This and most of what is known of him comes from Plato, who named a dialogue after him, the Theaetetus. He apparently died from wounds and dysentery on his way home after fighting in an Athenian battle at Corinth, now presumed to have occurred in 369 BC; some scholars argue alternately for 391 BC as his date of death, the date of an earlier battle at Corinth. The crater Theaetetus on the Moon is named after him.
Театет Афинский (др.-греч. Θεαίτητος; ок. 417 – ок. 369 до н. э.), предположительно сын Эфрония из афинской демы Суний, был греческим математиком. Его основные достижения связаны с исследованием иррациональных величин, результаты которых вошли в Книгу X «Начал» Евклида, и доказательством того, что существует ровно пять правильных выпуклых многогранников. Друг Сократа и Платона, он является центральным персонажем одноименного сократического диалога Платона. Театет, как и Платон, был учеником греческого математика Феодора Киренского. Киринея была процветающей греческой колонией на побережье Северной Африки, на территории современной Ливии, в восточной части Сидринского залива. Феодор исследовал теорию несоизмеримых величин, и Театет с большим энтузиазмом продолжил эти исследования, в частности, классифицировав различные формы иррациональных чисел в зависимости от способа их представления в виде квадратных корней. Эта теория подробно изложена в Книге X «Начал» Евклида. Театет был одним из немногих греческих математиков, родившихся в Афинах. Большинство древнегреческих математиков происходили из многочисленных греческих городов, разбросанных по побережью Ионического моря, Черного моря и всему Средиземноморскому бассейну. Он, очевидно, был похож на Сократа приплюснутым носом и выпуклыми глазами. Это и большая часть того, что известно о нем, происходит из работ Платона, который назвал в его честь один из своих диалогов – «Театет». По-видимому, он умер от ран и дизентерии по дороге домой после участия в афинской битве при Коринфе, которая, как считается, произошла в 369 г. до н. э.; некоторые ученые предполагают, что он умер в 391 г. до н. э., во время более ранней битвы при Коринфе. Кратер Театет на Луне назван в его честь.
Theaetetus of Athens (,/θ//iː//ɪ/'/t//iː//t//ə//s/; Theaítētos; c. 417 – c. 369 BCE), possibly the son of Euphronius of the Athenian deme Sunium, was a Greek mathematician. His principal contributions were on irrational lengths, which was included in Book X of Euclid's Elements and proving that there are precisely five regular convex polyhedra. A friend of Socrates and Plato, he is the central character in Plato's eponymous Socratic dialogue. Theaetetus, like Plato, was a student of the Greek mathematician Theodorus of Cyrene. Cyrene was a prosperous Greek colony on the coast of North Africa, in what is now Libya, on the eastern end of the Gulf of Sidra. Theodorus had explored the theory of incommensurable quantities, and Theaetetus continued those studies with great enthusiasm; specifically, he classified various forms of irrational numbers according to the way they are expressed as square roots. This theory is presented in great detail in Book X of Euclid's Elements. Theaetetus was one of the few Greek mathematicians who was actually a native of Athens. Most Greek mathematicians of antiquity came from the numerous Greek cities scattered around the Ionian coast, the Black Sea and the whole Mediterranean basin. He evidently resembled Socrates in the snubness of his nose and bulging of his eyes. This and most of what is known of him comes from Plato, who named a dialogue after him, the Theaetetus. He apparently died from wounds and dysentery on his way home after fighting in an Athenian battle at Corinth, now presumed to have occurred in 369 BC; some scholars argue alternately for 391 BC as his date of death, the date of an earlier battle at Corinth. The crater Theaetetus on the Moon is named after him.