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Matter/antimatter annihilation and conservation of mass

  1. Oct 12, 2015 #1
    I was hoping to learn a little bit more about matter-antimatter annihilation. As I understand it, when a particle meets an antiparticle, they are both annihilated and energy is produced. Does this contradict the laws of conservation of energy and conservation of matter? I haven't had much luck finding the answer online or in other threads here, but if there's anything you could refer me to, I would appreciate it.
  2. jcsd
  3. Oct 12, 2015 #2


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    Nothing wrong with annihilation of matter-antimatter... the 2 particles that get annihilated, produce for example 2 gamma rays that carry the energy/momentum needed.
  4. Oct 12, 2015 #3


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    There is no energy produced, energy is conserved. The mass of the particles has energy as well. This energy can get transformed to something else, like radiation.
    There is no conservation law for matter.
  5. Oct 16, 2015 #4
    There is only conservation of matter (nucleons and electrons) in Chemistry probably. When it comes to subatomic physics there is no such thing.

    A more familiar example is in a nuclear reaction, there is loss in mass. For rest particles, we have E = m0c2, so the mass loss is an indication of lost energy which is transferred to the outgoing particles (e.g. photon).

    To properly understand the real theoretical foundation of such process, you might need to look at lowest order quantum electrodynamics processes.
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