In 1928, British physicist Paul Dirac derived an equation combining quantum theory and special relativity to describe the behavior of an electron that moves with relativistic speed.
In 1933, Dirac was awarded the Nobel Prize for the derived equation. Like the equation x² = 9 (either x = 3 or x = -3), the Dirac equation also has two possible solutions: the first one is for an electron with positive energy, the second one is for an electron with negative energy.
However, at that time, classical physics dictated that the particle energy is exclusively expressed by a positive number.
Dirac interpreted his own equation in such a way that for each particle, there is a corresponding antiparticle, exactly repeating it, but with the opposite charge.
For example, for an electron, there is an anti-electron or positron, which is absolutely identical in all respects but has a positive electric charge.
This discovery has actually opened up the understanding that there may be whole galaxies consisting of antimatter.
But in the case of contact of matter and antimatter, they annihilate, disappearing in a flash of energy. The big bang was supposed to create an equal amount of matter and antimatter. But the question arises, why is there much more matter in the Universe?
Antimatter is formed naturally during various decays of natural, radioactive isotopes, for example, potassium-40. Antiparticles also arise in an environment with a sufficiently high temperature (lightning, for example).
In addition, antimatter can be obtained artificially in particle accelerators. In particular, CERN does this.
Antimatter has a number of applications, both intended and already quite real.
It was considered as one of the components of nuclear weapons. However, it is quite difficult to be obtained in large quantities, and there is no clear understanding of the solution to this problem.
Isolated, accumulated antimatter can be used as fuel for space travel. Probably, one gram will be enough for a manned mission to Mars.
Thus, in the reaction of 1 kg of antimatter with 1 kg of substance, 180 petajoules would be released, slightly less than the recoil of the Tsar bomb, weighing 26,500 kg, the largest thermonuclear weapon ever detonated.
Finally, the real application is Positron Emission Tomography (PET). It is an extremely useful and valuable tool for studying the functioning of the body.
A person is given sugar containing radioactive oxygen obtained in a medical cyclotron. Oxygen emits positrons, instantly annihilating, emitting gamma rays.
One positron is cheap, its cost is less than a cent. But it is very small and weighs about 10⁻²⁷ grams. It is estimated that the production of only 10 milligrams of positrons will require $250 million.
And per gram of anti-hydrogen, a person will have to pay as much as $62.5 trillion. For comparison, the production of nuclear weapons under the Manhattan project required $23 billion, taking into account inflation.