Tell me about anti-matter? Has it been discovered or is it just a theory?

Question

I have read that one raison and one anti-matter raison would have the energy to furish New York for a whole day. A box for a year.

Answer 1

What is Antimatter?
The world is made up of matter in the form of (mostly) atoms and molecules. Of course, atoms themselves can be broken down into several fundamental particles, the proton, neutron and electron. There are many other fundamental particles that we know of and scientists have long been trying to come up with a comprehensive theory that will describe all of them, and their interactions.

For every matter particle, there is a corresponding antiparticle — these antiparticles collectively are what we know as antimatter. They have properties that are similar but opposite to their corresponding matter particles — for example the same mass and the same magnitude but opposite sign of charge. When a particle and its antiparticle meet, they annihilate — disappearing in a burst of energy. What happens in between can be quite interesting, and is the focus of CAMS.

Where do you get antimatter?
Most forms of antimatter are quite hard to come by and can only be seen at big accelerator facilities, such as CERN in Switzerland (or in deep outer space). However, the electron's antiparticle, the positron, is reasonably accessible. It has the same mass as en electron but has a positive charge, rather than a negative charge. This is either through generating positrons using a (relatively) small accelerator called a LINAC, or by using an artificially made radioactive isotope which emits positrons, such as 22Na. CAMS uses radioactive sources to give us the positrons to study interactions of antimatter with matter.

What is a Positron?
A positron is the antiparticle of the electron. It has the same mass but opposite charge (positive instead of negative). When it annihilates with an electron, they turn into gamma rays.

What is Positronium?
Positronium is when a positron and an electron are bound together. In a normal atom, there is a heavy nucleus with a positive charge, with electrons orbiting around it. In the case of positronium, the positive nucleus is replaced by the positive positron. Essentially it is an exotic type of atom. It is very light, as the positron is not heavy like an ordinary nucleus and it only lives for 120 picoseconds or 142 nanoseconds, depending on the configuration. You can even make molecules out of it!

Annihilate, what's that?
Remember E=mc2? When an antiparticle meets its corresponding particle, the mass is converted into energy, and sometimes other particles. In the case of a positron and electron annihilating, the energy is carried by gamma rays, usually either two or three gamma rays are emitted per annihilation event.

Can't you use antimatter for bombs, space drives and that sort of thing?
Not really. For anything like that you would need enormous amounts of antimatter, which you just can't find here on Earth. If you tried to make it, you'd soon find it took a VERY long time and is VERY expensive, a nanogram (one thousandth millionth of a gram) of 22Na costs about $35,000 (Aussie dollars). Even to get a gram, you would need about twice the GDP of the USA (in 2004).

Answer 2

Anti matter is made up of a positive electron and a negative proton. It does exist. When they meet they explode with more power per mass than any other substance. Here is a little clip from the web site listed below;
The Reality of Antimatter
By Robert Roy Britt
Senior Science Writer
posted: 07:00 am ET
29 September 2003

Antimatter sounds like the stuff of science fiction, and it is. But it's also very real. Antimatter is created and annihilated in stars every day. Here on Earth it's harnessed for medical brain scans.

"Antimatter is around us each day, although there isn't very much of it," says Gerald Share of the Naval Research Laboratory. "It is not something that can be found by itself in a jar on a table."

So Share went looking for evidence of some in the Sun, a veritable antimatter factory, leading to new results that provide limited fresh insight into these still-mysterious particles.

Answer 3

About three years back an atom of anti-hydrogen was made. We know enough about antiparticles to be sure that you could make antiatoms of all the elements in the periodic table and they'd obey all the usual rules of chemistry, so you could make complex structures like living things with them.

Answer 4

Anti-matter is theoretical, I believe.

Matter is positively charged nucleus, with negatively charged electrons orbiting it.

Anti-matter has a negatively charged nucleus, and postive electrons.

Answer 5

It's actually been "discovered" already. They throw anti-particles and their corresponding particle together in "particle accelerators" and create rare and exotic particles from thier impact!