Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

B Matters and anti-matters

  1. Mar 5, 2016 #1
    What will happen when a particle collide with other particles' anti-self? For example, down quark with anti-up quark , up quark with positron etc
  2. jcsd
  3. Mar 5, 2016 #2


    User Avatar
    Science Advisor
    Gold Member
    2017 Award

    It will scatter somehow. You can think of all kinds of elastic and inelastic collisions compatible with the conservation laws. If something is not forbidden by conservation laws, it will happen with some probability. Perhaps I don't understand right your question, but there's nothing special about anti-particles. They just undergo elastic or inelastic reactions as particles.
  4. Mar 5, 2016 #3


    User Avatar
    Science Advisor

    Most mesons are a combination of a quark and an anti-quark.
  5. Mar 6, 2016 #4


    User Avatar
    Gold Member

    You can see this in the decay of the charged and neutral pion decays.
    The decay of the neutral pion is basically a matter-antimatter annihilation process that can be seen through the decay equation:
    π0 -> γ + γ
    The annihilation occurs because neutral pions always have a quark and an antiquark from the same flavor.
    But you can't see this annihilation process in charged pions where the flavors are different
    π± -> π0 + e± + electron neutrino/antineutrino
  6. Mar 6, 2016 #5


    User Avatar
    2017 Award

    Staff: Mentor

    That is an extremely rare decay (about 10 decays in a billion). The most common decay is ##\pi^+ \to \mu^+ \nu## and ##\pi^- \to \mu^- \bar\nu## (probability of more than 99.98%).

    Free quarks do not exist, you cannot "collide" quarks. You can have them in the same meson, with implications discussed above.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted