Do you know, what is antimatter

A cloud chamber photograph of the first observed positron, 2 August 1932.

Antimatter

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Modern physics
${\hat {H}}\|\psi _{n}(t)\rangle =i\hbar {\frac {\partial }{\partial t}}\|\psi _{n}(t)\rangle$ $G_{\mu \nu }+\Lambda g_{\mu \nu }={\kappa }T_{\mu \nu }$ Schrödinger and Einstein field equations
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In modern physics, antimatter is defined as matter composed of the antiparticles (or "partners") of the corresponding particles in "ordinary" matter. Minuscule numbers of antiparticles are generated daily at particle accelerators—total artificial production has been only a few nanograms^[1]—and in natural processes like cosmic ray collisions and some types of radioactive decay, but only a tiny fraction of these have successfully been bound together in experiments to form antiatoms. No macroscopic amount of antimatter has ever been assembled due to the extreme cost and difficulty of production and handling.

Theoretically, a particle and its antiparticle (for example, a proton and an antiproton) have the same mass, but opposite electric charge, and other differences in quantum numbers.

A collision between any particle and its anti-particle partner leads to their mutual annihilation, giving rise to various proportions of intense photons (gamma rays), neutrinos, and sometimes less-massive particle–antiparticle pairs. The majority of the total energy of annihilation emerges in the form of ionizing radiation. If surrounding matter is present, the energy content of this radiation will be absorbed and converted into other forms of energy, such as heat or light. The amount of energy released is usually proportional to the total mass of the collided matter and antimatter, in accordance with the notable mass–energy equivalence equation, $E = mc 2$ .^[2]

Antimatter particles bind with each other to form antimatter, just as ordinary particles bind to form normal matter. For example, a positron (the antiparticle of the electron) and an antiproton (the antiparticle of the proton) can form an antihydrogen atom. The nuclei of antihelium have been artificially produced, albeit with difficulty, and are the most complex anti-nuclei so far observed.^[3] Physical principles indicate that complex antimatter atomic nuclei are possible, as well as anti-atoms corresponding to the known chemical elements.

There is strong evidence that the observable universe is composed almost entirely of ordinary matter, as opposed to an equal mixture of matter and antimatter.^[4] This asymmetry of matter and antimatter in the visible universe is one of the great unsolved problems in physics.^[5] The process by which this inequality between matter and antimatter particles developed is called baryogenesis

Properties[edit]

Theorized anti-gravitational properties of antimatter are currently being tested at the AEGIS experiment at CERN.^[19] Antimatter coming in contact with matter will annihilate both while leaving behind pure energy.^[20] Research is needed to study the possible gravitational effects between matter and antimatter, and between antimatter and antimatter. However research is difficult considering when the two meet they annihilate, along with the current difficulties of capturing and containing antimatter.

There are compelling theoretical reasons to believe that, aside from the fact that antiparticles have different signs on all charges (such as electric and baryon charges), matter and antimatter have exactly the same properties.^[21]^[22] This means a particle and its corresponding antiparticle must have identical masses and decay lifetimes (if unstable). It also implies that, for example, a star made up of antimatter (an "antistar") will shine just like an ordinary star.^[23] This idea was tested experimentally in 2016 by the ALPHA experiment, which measured the transition between the two lowest energy states of antihydrogen. The results, which are identical to that of hydrogen, confirmed the validity of quantum mechanics for antimatter.^[24]^[25]