Matter-Antimatter Conversions

Most recent answer: 10/22/2007

How is antimatter formed and why is there less antimatter in the universe than matter if they "explode" when they come into contact?
- Leonid Kelner (age 15)
Saint-Henri High, Montreal, Qc, Ca
To make antimatter, scientists build big equipment called "particle accelerators." These accelerators make tiny particles (usually either protons or electrons) move extremely fast (almost as fast as the speed of light). That gives these particles a lot of energy. When scientists shoot these particles into a block of material (like steel) they tend to produce a "shower" of new particles, some of which will be antimatter. Scientists then use some other equipment to catch this antimatter and store it until they need it later.

The other part of your question is a tricky one that scientists are still trying to answer. We believe that in the Big Bang that produced the Universe, matter and anti-matter was produced in equal quantities (since this is what we observe in our accelerator experiments). If order for the universe we live in now to be made of mostly matter and very little antimatter (which seems to be the case), it must be true that the matter and anti-matter did not behave in exactly the same way. Searching for the cause of this "symmetry breaking" is a hot research topic right now.


(published on 10/22/2007)