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Speed of subatomic particles

  1. Jul 4, 2015 #1
    what might be the speed of subatomic particles ?
    The problem arises from all the interactions of subatomic particles are known to be super fast . thus wish to know how fast they are .
    Does time have anything to do with subatomic particles ? ( Relativity )
    " am a science enthusiast just out of curiosity "
  2. jcsd
  3. Jul 4, 2015 #2


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    Staff: Mentor

    Same as for anything else - any speed from zero all the way up to very close to the speed of light.
    (The so-called "massless" particles such as the photon move at the speed of light).
  4. Jul 5, 2015 #3


    Staff: Mentor

    It needs to also be said in QM speed only has an actual value for free particles.

  5. Jul 5, 2015 #4
    Just substantiating this (in a non-technical manner)- three out of the 4 fundamental interactions (4 most elementary forces in nature) are mediated by gauge bosons in the Standard Model whose existence has been confirmed (think of gauge bosons as elementary particles which "carry" forces around). The strong interaction (which binds the nucleus) and the electromagnetic interaction (which keeps the electrons and protons together in the atom [warning, this classical interpretation breaks down in quantum mechanics]) is mediated by the gluon and photon respectively, and both of these bosons are massless, which means that these forces propagate through space (vacuum, really) at the speed of light. The weak interaction is mediated by the W ± and Z bosons, and these particles were initially theorized to be massless as well, but are now considered to be massive after the discovery of the Higgs boson, which confirms the Higgs mechanism. Basically, the Higgs mechanism says that there is a Higgs field throughout the universe, and 3 of its components interact with the W and Z bosons, thereby giving them mass (if I remember correctly, the fourth real component of the field produces the Higgs boson). Hence, the weak nuclear interaction propagates through space at speeds less than the speed of light.

    The fourth fundamental force, gravity, is mediated by the hypothetical "graviton" in the Standard Model (the graviton is theorized to be massless), but the existence of the graviton has so far not been confirmed. So we rely on General Relativity instead, which says that gravitational effects (waves) propagate through spacetime at the speed of light (the graviton's mass is predicted to be 0 [so it always moves at light speed] because it must match this result).

    So now you know what super fast exactly means :wink:
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