4 ms·

I guess it would be tough to keep these around in any substantial quantity.

• thaumasiotes 9y ago
  It's not usually a problem to have a large number of photons?
  • adrusi 9y ago
    Which are different because the result of a particle/antiparticle collision is the emission of photons so the quantity of photons is not changed by collisions.
• m3kw9 9y ago
  Unless it can only become one of the properties at one time