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Electron beam processing is used to irradiate materials in order to change their physical properties or sterilize medical and food products. [180] Electron beams fluidise or quasi-melt glasses without significant increase of temperature on intensive irradiation: e.g. intensive electron radiation causes a many orders of magnitude decrease of ...
It also revealed that physical objects do not change their parameters, such as total energy, position and momentum, as continuous functions of time, as it was thought of in classical physics: see atomic electron transition for example. Another crucial discovery was identical particles or, more generally, quantum particle statistics. It was ...
Thomson made the discovery around the same time that Walter Kaufmann and Emil Wiechert discovered the correct mass to charge ratio of these cathode rays (electrons). [35] The name "electron" was adopted for these particles by the scientific community, mainly due to the advocation by George Francis FitzGerald, Joseph Larmor, and Hendrik Lorentz.
The discovery of these particles required very different experimental methods from that of their ordinary matter counterparts, and provided evidence that all particles had antiparticles—an idea that is fundamental to quantum field theory, the modern mathematical framework for particle physics. In the case of most subsequent particle ...
The two discovering parties independently assign the discovered meson two different symbols, J and ψ; thus, it becomes formally known as the J/ψ meson. The discovery finally convinces the physics community of the quark model's validity. 1974 Robert J. Buenker and Sigrid D. Peyerimhoff introduce the multireference configuration interaction method.
Atoms were thought to be the smallest possible division of matter until 1899 when J. J. Thomson discovered the electron through his work on cathode rays. [37]: 86 [5]: 364 A Crookes tube is a sealed glass container in which two electrodes are separated by a vacuum.
The discovery of electromagnetic waves in space led to the development of radio in the closing years of the 19th century. The electron as a unit of charge in electrochemistry was posited by G. Johnstone Stoney in 1874, who also coined the term electron in 1894. [135]
With Thomson's discovery of the electron in 1897, scientist began the search for a model of the interior of the atom. Thomson proposed negative electrons swimming in a pool of positive charge . Between 1908 and 1911, Rutherford showed that the positive part was only 1/3000th of the diameter of the atom.