1. When matter comes into contact with antimatter there is a ginourmous explosion.
Yes, but what happens depends on how much kinetic energy the matter
and antimatter particles have. High-energy particle colliders such as
the ones at Fermilab
and antiparticles together at very high energies, in the hopes of
producing exotic, not-before-detected particles, and of measuring
precisely the properties of ones we already know about.
But see the answer below about the photons:
2. Do 'particles' in the electromagnetic spectrum count as matter?
Photons are their own antiparticles: an anti-photon is just a
photon. To a good approximation, photons do not interact with each
other (but you can search this web site for our explanations of how
much they do and under what circumstances). So a photon meeting an
anti-photon does not result in a ginormous explosion -- they just go
past each other nearly all of the time.
3. If not, couldn't a magnetic field be used to contain positrons or antiprotons?
Very good! This is exactly how antiprotons and other antiparticles
are stored at particle-physics research laboratories. Charged particles
feel forces when traveling through magnetic fields. In practice, beams
of antiprotons (or protons, or electrons, or positrons, or lots of
other goodies) can be made to travel in circular paths with the help of
magnets. Fermilab's Tevatron ring, for exmaple, is four miles in
circumference and consists of a pipe with a very good vacuum in it.
Very strong magnets supply a field perpendicular to the plane of the
ring. A beam of antiprotons whirls around in one direction and a beam
of protons whirls around in the other. These beams can be stored in
this way for days on end (but collisions between the protons and
antiprotons, and between the beams and residual gas molecules will
eventually make the beams get weaker and weaker -- same energy, but
4. Another thing that bugs me is: Why should the big bang have happened in the first place if it was all down to chance?
Don't expect a definite or reliable answer to this one. Just for
fun, I'll run one of the many possible answers by you. It may be that
the 'chance' in quantum mechanics has nothing to do with randomness of
which event will occur but rather is a subjective impression because
ALL the events which quantum mechanics allows do occur. Any one version
of you can only experience one little chain of these possibilities, so
it feels chancy. That seems to be the most natural reading of the
quantum time-dependence equations, although like other ways of looking
at quantum mechanics it has serious problems. It may be that one piece
of the quantum state underwent the big bang simply because that's one
possibility and all possibilities occur.
Mike W. and Tom J.
(republished on 07/20/06)