موسوعة العلمـاء و المخترعين .. العلمـاء بالترتيب حسب اسم الشهرة .. الحرف ٣_ج

Encyclopedia of Scientists and Inventors.. Scientists in order according to their nickname.. Letter J_3

⏹Janes, Sir James Hopwood
Jeans, Sir James Hopwood

English mathematical physicist (1877-1946)
- Jens learned in Cambridge, then headed the Royal Astronomical Society for about three years. He also headed the British Society.
He studied the kinetic (dynamic) theory of gases, then conducted research on the dynamics of stars. He was one of those who developed the fission theory to refer to the formation of binary and multi-star systems. Jens also developed a theory of spiral nebulae. He suggested the tidal theory of the formation of planets.
The solar system, and this theory calls for the belief that a great body passed relatively close to the sun, and caused a huge tidal wave in the form of a tongue from the body of the sun. Soon it was cut into blocks that remained suspended between the sun and the visiting body, and these blocks cooled, forming the planets.
He also pointed out that the kinetic energy of all stars is almost equal, meaning that the smaller stars move faster than the larger ones. Likewise, Jens indicated that uranium radiation has a temperature of five thousand eight hundred million degrees Celsius.

⏹ Geoffroy St. Aller Etienne
Geoffroy Saint-Hilair-Étienne

French naturalist (1772-1844) ·
Geoffroy received his education in Paris at the hands of Brisson, then joined the church, but his scientific inclinations did not allow him to continue: he played an active role in saving the teaching staff in the college in which he worked from the hands of Geoffroy's work as a professor of zoology at the new Museum of Natural History, the revolutionaries and cooperated with Kevier Cuvier in issuing a number of notes. After a long debate, he was convinced of Kivier's idea of ​​the unity of organic formation, meaning that all animals are composed of the same chemical elements, with the same number and the same bonds.
This led to his deviation towards the belief that the existing animal species could not mutate. When Geoffroy became blind and paralyzed at the age of sixty-eight, his son Isidore continued
his natural studies.