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The major problem is that it takes a lot of money to make just a small amount of anti-protons. You need a big costly accelerator and the production rate is small. The second problem is that you just can't store them in an ordinary bottle, they would just interact with the sides of the bottle and annihilate. You need what is called a storage ring which is a ring of magnets with a vacuum tube inside.
Never-the-less, there is such a ring at the CERN accelerator in Geneva, Switzerland where small amounts of anti-protons are stored and used for various experiments.
See: http://cerncourier.com/cws/article/cern/28112 for a nice news article.
On a larger scale, at Fermilab anti-protons are not only stored but accelerated and made to collide with real protons producing weird and wonderful new particles, for example the Top Quark and, hopefully, the Higgs boson.
(published on 09/29/2009)
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(published on 01/31/2013)
When a particle collides with its antiparticle, their rest masses are annihilated and converted to other forms of energy. This does obey physical law because, in a closed system, energy and momentum must be conserved, as well as some other quantities such as electronic charge. In this case, the energy that is in the form of rest mass in the two particles plus their kinetic energies is converted to energy in the form of rest masses and kinetic energies of other subatomic particles or (purely kinetic energies) of photons (light). This is just what happens between two particles.
It is hard to say exactly what would happen if you had a "chunk" of matter and antimatter and threw them together, but it would definitely be extremely energetic and violent, and therefore very difficult to test - even if we already had a large amount of antimatter, which is difficult to create. Furthermore, as the two "chunks" of different matters were pushed together, the forces caused by the reaction would cause a tremendous outward acceleration that would further complicate things. It's difficult for us to say what would happen quantitatively, although there may be some experts who know. If you're interested in antimatter though, you should check out some of the other questions we've had on the subject here.
Samson (mods by mw)
(published on 01/28/2013)
The first thing that popped into my mind was PET, Positron Emission Tomography. See http://en.wikipedia.org/wiki/Positron_emission_tomography. Positrons are the anti-particles of ordinary electrons. This procedure allows doctors to compose a three-dimensional image of the body for medical diagnostic purposes. I know it is used, I had one myself. In addition doctors at the CERN laboratory in Switzerland are investigating the use of anti-protons in cancer therapy. You can Google "antiproton therapy" to find out more about it.
Antimatter itself doesn't last very long so there are no long term environmental hazards. It annihilates as soon as it meets up with a suitable ordinary-matter particle. Finally, I should say that the study of anti-matter particles allows us to better understand the fundamentals of what the universe is made of and how it works.
(published on 05/30/2013)