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Antimatter 

Antimatter is literally matter which is the inverse or opposite of matter; particles which have charges opposite of regular matter.

Antimatter was first predicted by P.A.M. Dirac in his theory of quantum mechanics in 1928. Antiparticles were found soon after by Carl Anderson. Since then, research centers such as CERN and Fermilab produce antimatter particles on a daily basis. CERN uses a Proton Synchrotron machine to accelerate protons and then they inject them into the Antiproton Decelerator - a gigantic circular machine with a diameter of 18 km. Here the protons are smashed into a copper or iridium block of metal. The abrupt stop from such an incredible speed (about the speed of light) results in an enormous amount of energy released into a small volume, resulting in extreme temperatures greater than 10,000,000,000,000 Celsius. This enormous amount of heat and energy results in the spontaneous creation of matter-antimatter particles.

When antimatter comes in contact with regular matter - earth, air, whatever - it annihilates immediately in a 100% efficient reaction. A popular misconception is that this antimatter-matter reaction will someday allow antimatter for use as a source of fuel, or power source. Unfortunately, this is an impossible reality. Since antimatter is not found anywhere on Earth naturally (obviously), it must be created. With the equation E=mc2, it is IMPOSSIBLE to have a net gain of matter: the energy required running the accelerators would ALWAYS be more than the energy antimatter produced.

It's true that a quarter gram of antimatter has as much power as the nuclear bomb dropped on Hiroshima. This raises concern as to whether it could eventually be yielded as a terrorist device. Fortunately, it is IMPOSSIBLE to collect and store antimatter at this great of a density, and even if it were possible, with the current technology it would take billions and billions of years to yield that much. In fact, if CERN were to have kept all of the antimatter it ever produced; it would be enough to power a light bulb for about three seconds. Anyways, even with these things aside, it's completely impractical considering how much time, money, and energy is required to create antimatter.

This information is from the CERN official web site.
For more information visit:

www.cern.ch
www.fnal.gov
Isn't particle physics fun?
Antimatter by moltovivace April 1, 2005

Antimatter 

Antimatter in matter composed of the analogous antiparticles to ordinary matter. Physicists believe symmetry breakdown at the most fundamental levels after the Big Bang resulted in our universe where matter predominates and anti-matter is all but non-existant.

Anti-hydrogen consists of an anti-electron aka Positron, orbiting an Antiproton. Truly miniscule amounts of Anti-hydrogen (a few atoms) have been made in the largest accelerator laboratories.

When reacted with ordinary matter anti-matter would indeed release enormous amounts of energy according to E=MC^2. However, much of this energy is carried away in neutrinos, which interact so slightly with anything at all, matter or antimatter, capturing the output of a M-AM reactor would present another huge hurdle.

However, it may not necessarily take more energy input than output. This is based on the misconception that the input to the accelerators is the same energy as released by the reaction. The energy released by a future M-AM reactor comes from annihilation, rather than being stored energy from the accelerator drive & containment. Most of the huge power requirements of accelerators goes into their magnetic confinement system. Suppose it becomes possible to re-arrange the quarks constituting normal matter into the configuration of antimatter much more efficiently. This is a big science fiction IF, by the way. Thus if a “matter inverter” were to function reasonably efficiently, the downstream M-AM reactor would see a net gain.

One possibility would be to base the “matter inverter” on a hypothetical Bussard Ramjet. This would be a magnetic or electrostatic “scoop” that collects interstellar hydrogen to power a hypothetical interstellar spacecraft at relativistic speeds. An accelerator might not be needed, as the hydrogen & whatever other atoms are out there would be running into the craft at near-light speed already. Although the Bussard scoop field(s) would probably use a lot of power in its own right.

Remember and be warned, when one extrapolates science far enough beyond the frontiers of present knowledge, it becomes largely indistinguishable from science fiction!
Anti-Hydrogen and Anti-Helium are the two forms of antimatter that have been made on earth as of the early
Antimatter by ScienceGuy April 13, 2006

Antimatter Dimensions 

A clicker game based on creating antimatter and using it to buy antimatter dimensions that create more antimatter and more dimensions. Eventually you can start buying galaxies and shiz until you reach 1e308 antimatter, which causes the Big Crunch. Keep doing this and eventually you can break the limit and unlock a ton of cool shiz.
9th antimatter dimensions don't exist, if you know what I mean ;)

Antimatter Dick 

A dick so large it destroys anything it comes in contact with
Johnny literally destroyed my pussy last night, He has an Antimatter Dick!
Antimatter Dick by MrSokol January 14, 2020

Antimatter 

Antimatter is something that doesn't matter at all.
Guy one: Hey man, my girlfriend has bought this awesome new sweater!!!
Guy two: Come on man, stop bothering me with you useless antimatter.

antimatter 

Most beneficial yet dangerous element known to man. One particle of antimatter can fuel New York's power for a day. Yet it has a drawback however; It is completely destructive upon contact with another element (yes, EVEN AIR). Upon contact, one particle is enough to cause an even more massive explosion, perhaps (researching) double the destruction level of an Atomic bomb.

It is currently being researched at CERN (a European Organization for Particle Physics Research located just west of Geneva, Switzerland) and Fermilab. Both of these organizations are researching on making antimatter on large quantities and fuel.
This can be very beneficial yet destructive.

Star Trek geeks/nerds/appreciators (or whatever) knows antimatter and its use as a power source.

There are antimatter weapons currently in production.

OH SHIT! ANTIMATTER EXPLOSION!
antimatter by Welp May 30, 2004
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