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Annihilation is defined as "total destruction" or "complete obliteration" of an object;〔 〕 having its root in the Latin ''nihil'' (nothing). A literal translation is "to make into nothing". In physics, the word is used to denote the process that occurs when a subatomic particle collides with its respective antiparticle, such as an electron colliding with a positron.〔 〕 Energy and momentum are conserved, and the annihilated particles are replaced by photons, electromagnetic wave quanta with zero rest mass. Antiparticles have exactly opposite additive quantum numbers from particles, so the sums of all quantum numbers of the original pair are zero. Hence, any set of particles may be produced whose total quantum numbers are also zero as long as conservation of energy and conservation of momentum are obeyed. When a particle and its antiparticle collide, their energy is converted into a force carrier particle, such as a gluon, W/Z force carrier particle, or a photon. These particles are afterwards transformed into other particles.〔 〕 During a low-energy annihilation, photon production is favored, since these particles have no mass. However, high-energy particle colliders produce annihilations where a wide variety of exotic heavy particles are created. This is an example of renormalization in quantum field theory— the field theory being necessary because the number of particles changes from one to two and back again. ==Examples of annihilation== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「annihilation」の詳細全文を読む スポンサード リンク
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