# Jabir Ibn Aflah

Date of Birth: 1100

Age: 50

Place of birth: Al-AndalusaGod death 1150

**Who invented torquetum?**

Abu Muhammad Jabir ibn Aflah al-Ishbili created treatise Almagest `` Improving the comments and processing of the classic work of Ptolemy Almagest `` ( `Almagest`), for many years served as the basis for astronomical research. Aflah work was first criticized `Almagesta` in the Islamic West. In particular, Jabir put forward doubts about the mathematical foundations of `` Almagest. For example, it has replaced the use of the theorem of Menelaus (Menelaus), the classical theorem of affine geometry, on the main provisions of spherical trigonometry - in an attempt to increase the accuracy of the mathematical operation.

Theorems have been developed to replace a group of Islamic mathematicians of the 10th century, including Abu al-Wafa Buzdzhani (Abu al-Wafa `Buzjani), as well as Abu Abd Allah Muhammad ibn Muadh al-Dzhayyani (Abu Abd Allah Muhammad ibn Muadh al-Jayyani), who worked in Andalusia (Andalusia) in the 11th century. Jabir, however, has not been formally referred to any one of the mathematicians in his treatise.

One of the significant changes in Aflaha Ptolemaic interpretation concerns the placement of the orbit of Venus and Mercury - the minor planets - beyond the sun. In the case of an original work of Ptolemy, the orbits of Venus and Mercury were located between the moon and the sun.

Jabir ibn Aflah - the inventor of an astronomical instrument, known as torquetum. Torquetum rightly be regarded as an analog computing device, as it allows to measure not only in the horizontal, equatorial and ecliptic coordinate system, but also to the transitions between them.

Several Islamic later writers were influenced by Jabir, including Ibn Rushd (Ibn Rushd) and Nur ad-Din al-Bitrudzhi (Nur ad-Din al-Betrugi). Both of them worked in Andalusia. Work Improvement Almagest `` spread to Egypt (Egypt) in the 12th century thanks to the efforts of prominent Jewish philosopher and theologian Maimonides (Maimonides), and then by the end of the 13th century made it to the east.

`` Improving the Almagest was translated from Arabic into Hebrew and Latin. Translated into Latin engaged Gerard of Cremona (Gerard of Cremona), which has contributed to the popularization of astrology in Western Europe. Jabir Labour has wide influence on later mathematicians and astronomers and helped the development of trigonometry in Europe.

Much of the material on spherical trigonometry in the work of the German mathematician Regiomontanus (Regiomontanus) `Of all kinds treugolnikov` (` On Triangles`) was directly borrowed from the treatise Aflaha. The provisions of trigonometry, which Nicolaus Copernicus (Nicholas Copernicus) said in the first part of its landmark labor `On the Revolutions of the Heavenly Spheres `(` De revolutionibus `), apparently, there were also not without the influence of reasoning Jabir.