In the intense heat of the Big Bang, particles of matter were forged out of pure energy. But for every particle of matter created, a 'twin' was also born - an 'antiparticle' identical in mass but with opposite electric charge.
For the first few instants of its existence the Universe was balanced, with matter and antimatter created in equal abundance. Then just one second after the Big Bang, the antimatter had all but disappeared, together with almost all the matter, leaving a minute amount of matter alone to form everything that we see around us – from the stars and galaxies, to the Earth and all life that it supports.
Antimatter: a mirror image of matter
Our world is made of matter, which consists of three types of particles called electrons, protons and neutrons. Each particle has a specific mass and electric charge. For example, the electron has a negative charge, and the proton a positive charge.
Antimatter particles have the same mass as the particles that make up our world, but carry the opposite charge. For example, the electron, which has a negative charge, has an antimatter 'twin' with the same mass but the opposite charge; we call the 'anti-electron' a positron.
Particles and antiparticles go together. Imagine sitting on a sandy beach. When you dig a hole, you also create a pile of sand. One cannot be made without making the other: they are complementary - just like particles and antiparticles.
Antimatter and matter were created in equal amounts in the Big Bang, but we don't see antimatter around us today.
Video on How Particle were formed in space.
E = mc2
Einstein’s famous formula means that 'mass is condensed energy'. Since 'c' is the speed of light, which is a very large number, the equation tells us that a small amount of mass contains an enormous amount of energy. It is like exchanging money between different currencies, with a huge exchange rate.
A mass of 1 kg contains an energy of 90 million gigajoules, equivalent to worldwide energy consumption over 90 minutes.
Highly volatile
When antiparticles and particles meet, they destroy each other. This process, called 'annihilation', liberates all the energy that is stored in their mass. Annihilation can create gamma-rays or even new particle-antiparticle pairs.
CERN scientists are exploring big mysteries such as: if matter and antimatter were created in equal amounts during the Big Bang, and matter and antimatter annihilate, then why is all this matter left-over to form our Universe?
Making antimatter
We don't find antimatter around us; in order to study antimatter it has to be made.
Transforming energy into mass
When enough energy is squeezed into a very small space, such as during high-energy particle collisions at CERN, particle-antiparticle pairs are produced spontaneously. The energy given to the accelerated particles has to be at least equivalent to the mass of the new particles in order for this to occur; the more energy that is put into particle collisions, the more massive the particles and antiparticles that can be produced.
When energy transforms into mass, both matter and antimatter are created in equal amounts. 
Antimatter at CERN
Antimatter is produced in many experiments at CERN. In collisions at the Large Hadron Collider the antiparticles that are produced cannot be trapped because of their very high energy - they annihilate harmlessly in the detectors. The Antiproton Decelerator at CERN produces much slower antiprotons that can be trapped. These antiprotons can then be studied to explore questions such as: do antiparticles fall upwards?
Antimatter production in practice
At CERN, protons with an energy of 26 GeV (about 30 times their mass at rest) collide with nuclei inside a metal cylinder called a target. About four proton-antiproton pairs are produced in every million collisions. The antiprotons are separated from other particles using magnetic fields and are guided to the Antiproton Decelerator, where they are slowed down from 96% to 10% of the speed of light. They are ejected and run through beam pipes into experiments to be trapped and stored. 
Small, very small quantities
Even if CERN used its accelerators only for making antimatter, it could produce no more than about 1 billionth of a gram per year. To make 1 g of antimatter - the amount made by Vetra in the movie - would therefore take about 1 billion years.
The total amount of antimatter produced in CERN’s history is less than 10 nanograms - containing only enough energy to power a 60 W light bulb for 4 hours.
Trapping antimatter
In order to study antimatter it has to be kept separate from matter, to prevent it from annihilating. Electrically-charged antimatter can be trapped in a device called a Penning trap.
The Penning trap requires an ultrahigh vacuum. Inside the trap, magnetic fields force the charged antiparticles to spiral around the magnetic field lines, and electric fields confine them along the magnetic axis.
No-one has yet managed to trap electrically neutral antimatter.
World record
The world record for storing antiparticles is held by the TRAP experiment at CERN: it kept a single antiproton in a Penning trap for 57 days! The scientists performed very precise measurements of its mass and charge before the trap was switched off and the antiproton ... annihilated.
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