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antimatter |
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antimatter: see antiparticle antimatter, composed of atoms made up of antiprotons and antineutrons in a nucleus surrounded by positrons. A very simple type of "atom" incorporating antiparticles is positronium, a brief pairing of a positron and an electron that may occur before their annihilation. ..... Click the link for more information. . antimatterSubstance composed of elementary particles having the mass and electric charge of ordinary matter (such as electrons and protons) but for which the charge and related magnetic properties are opposite in sign. The existence of antimatter was posited by the electron theory of P.A.M. Dirac. In 1932 the positron (antielectron) was detected in cosmic rays, followed by the antiproton and the antineutron detected through the use of particle accelerators. Positrons, antiprotons, and antineutrons, collectively called antiparticles, are the antiparticles of electrons, protons, and neutrons, respectively. When matter and antimatter are in close proximity, annihilation occurs within a fraction of a second, releasing large amounts of energy. |
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| He traces the history of astrophysics, explores the possibility of life on other planets, and introduces the idea of antimatter. Antimatter, for instance, was discovered a few decades ago and is used to make medical diagnoses, like chemotherapy. Your work seems, if not antithetical to a distribution model, actively resistant--or a kind of antimatter, removed yet reactive. |
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antimatter
