Theory Matter and Antimatter

Antimatter Discovered

After Einstein demonstrated the relationship between space and time, and energy and mass, after Max Planck devised the quantum theory (light behave as a wave and as particles packets), their concepts were applied to the atom in the 1920s by Schrodinger and Heisenberg, the latter inventing the quantum theory of physics. Trying to reconcile this new physics with Special Relativity, to explain behavior of particles at relativistic speeds, British theoretical physicist Paul Dirac in 1928 wrote an equation that described an electron moving close to the speed of light as he realized that there had to be both a positive and a negative solution to his equation. He later interpreted this mathematical quirk as suggestive of the existence of an anti-electron, now called a positron, and theorized that antimatter equivalents should exist for every particle. Each particle was supposed to have its antiparticle, matching it totally except for the electric charge as when that pair meets, both particles annihilated themselves, creating a explosion of enery. From 1930 onward, experiments began to look for these exotic particles. Experimentalist Carl Anderson confirmed the positron's existence in 1932 like a byproduct of cosmic rays hitting Earth's atmosphere, when he found a particle that seemed like an electron except that when it travelled through a magnetic field, its trajectory bent in the opposite direction. Physicists soon realized that positrons were routinely produced in collisions: smash particles together with enough energy and some of that energy can turn into matter–antimatter pairs. By the 1950s, researchers had begun to exploit this energy-to-particle conversion to produce antiprotons. But it took decades to find a way to make enough of them to capture and study. Creating positrons is fairly straightforward. The particles are produced in certain types of radioactive decay, and can be readily caught with electric and magnetic fields. But the higher-mass antiproton is another story. Antiprotons can be made by slamming protons into a dense metal, but they emerge from such collisions moving too fast to be held by an electromagnetic trap. British scientists by 2011 found that electron is a perfect sphere by less than 0.000000000000000000000000001 of a centimeter. That has implication about antimatter as electrons previously were considered distorted in shape causing its antimatter opposite, the positron, to behave in different ways. Cosmic rays were then the only way to study highly accelerated particles as cosmic rays hitting in the Earth's atmosphere can occasionally create a particle of antimatter. Cosmic rays are charged particles, mostly protons, that come from the interstellar space, beyond the solar system. They are carrying a large energetic punch. In 1937, Italian physicist Ettore Majorana updated Dirac's theories suggesting that fermions should be their own antiparticles, a hypothesis dubbed the 'Majorana fermion.' The first evidence of the theory was found by mid-2017 only as some of such fermions are of interest in research about quantum computers

A Whole World of Antiparticles

Researches accelerated with the 1940s and the invention of the first particle accelerators, and eventually, in 1955, was found the antiproton (Nobel Prize 1959), and in 1960 the antineutron. The three main components of the atom -the proton, the neutron, the electron- had been found to have their antiparticles, The physicists hence wanted to know whether the fundamental antiparticles might bind together to form "antiatoms". And the answer was yes. But it took too steps however. In 1965 (CERN, and Brookhaven National Laboratory) the antideuteron was found. The antideuteron is the opposite of a deuteron, a nucleus of deuterium. Being an "anti-nucleus", it is just the opposite of the deuteron, and is made of one antiproton and one antineutron. More recently, in 1995 (CERN) and 1996 (Fermilab), researchers were successfull in making a positron (an antielectron) stick to an antiproton, thus yielding an antiatom of hydrogen (9 of them were first created at the CERN). As hydrogen makes up about the two-thirds of the Universe, finding the anti-hydrogen is an important step. When antiparticles meet particles, they annihilate each other in a release of energy. The annihilation of both a electron and a positron, further, yields gamma rays. Antiparticles also naturally occur as byproducts of the decay of the elements (e.g. when an atom of Carbon 14 decays, a neutron decays into a proton plus an electron, and an electron antineutrino)

The only way today to create some antimatter is to smash particles together at nearly the speed of light inside a particle accelerator. In the effort to be able to contain manmade antimatter particles, physicists until now have just been able to slow and trap the antiprotons only, through a magnetic field confining the particles in a vacuum. Physicists have not be able however to trap larger particles like antihydrogen atoms as a whole. Scientists at the CERN, however, by 2011, have been able to isolate 112 antihydrogen atoms by 16 minutes, with the procedure now almost a routine and experiments to come about the exotic compound. As antimatter annihilate with matter, a container for antimatter is usually made of magnetic fields . An unknown answer is whether such clumping might be allowed to be annihilating, acting like an antimatter nuclear weapon. Such a purpose is illustrated in the 'Angels and Demons' movie, a second episode to the 'Da Vinci Code', where the Vatican is threatened of destruction by such an antimatter bomb!

Antimatter also is produced on Earth above thunderstorms! Brief bursts produced inside thunderstorms, as called terrestrial gamma-ray flashes or TGFs, associated with lightning likely are producing antimatter particles acting like enormous particle accelerators emitting gamma-ray flashes and high-energy electrons and positrons which are then riding Earth's magnetic field. TGFs likely arise from the strong electric fields near the tops of thunderstorms as, under the right conditions, the field becomes strong enough that it drives an upward avalanche of electrons. Reaching speeds nearly as fast as light, the high-energy electrons give off gamma rays when they're deflected by air molecules yielding the TGF. The cascading electrons produce so many gamma rays that they blast a electrons and positrons beam clear out of the atmosphere due to the gamma-ray energy turning into a pair of particles: an electron and a positron. Such particles are starting at a altitude of 9.3 miles (15 km) as they can reach up to 373 miles (600 km)

Astronomical Consequences

Although it was a while speculated that antimatter would be equivalent in amount to matter in the Universe to matter -hence an anti-Universe might exist, it is now believed that Universe is mostly made of matter and that there is no such anti-Universe. Soon during the Big Bang, matter eventually won over antimatter: for each billion antimatter particles, there eventually were a billion matter particles plus one. And, as temperature dropped quickly to a level where no more particles-antiparticles couples might be created, all the couples annihilated each other, and only the surplus of matter eventually remained. The origin of this fundamental imbalance between matter and antimatter in the Universe remains one of the biggest mysteries in physics. Any difference in nature between matter and antimatter, generally, would mean the violation of a principle called 'charge, parity and time reversal (CPT) symmetry'. According to this principle, a mirror-image Universe that is filled with antimatter and in which time runs backwards will have the same laws of physics as our own. Space-born missions kept on however to study possible antiparticles coming from somewhere in the Universe (Space Shuttle in 1998, ISS is still scheduled for this in 2004). The Space Shuttle 1998 experiment did not detect any heavy particle of antimatter among 3 million nuclei as some source state that that prototype instrument had provided enough information to make physicists reanalyze some of their theories as none of the results seen could be explained by existing theory. The research is now mainly aimed to find, if any, leftover antimatter dating back to the Big Bang era. Our matter-preferred Universe might be due to the concept of "charge-parity" violation (or CP violation), which was devised by Andrei Sakharov about 1967. CP violation is an assymmetry between particles and their antiparticles in the way they decay. Finding this CP violation is too a field of the present researches. Four sub-atomic particles are known to prefer matter over antimatter, a other reason for the apparent lack of antimatter in the Universe. The discovery of some antimatter in the Universe might allow scientists to tell how long the inflation lasted, by the beginnings of the Universe, as recent searches are mostly turning to study the collisions between galaxy clusters, which could release antimatter, among their X-rays and gamma-rays radiations. In the same order of idea, antimatter could keep infering into the existence of a anti-Universe, as dark matter might be related and constitute entire galaxies and emitting cosmic rays in the antimatter, with anti-electrons and protons. First findings from the International Space Station antimatter experiment in 2013 confimed how the ratio of positrons compared to electrons in the Universe changes depending on their energy as it is unknown whether that comes from dark matter particles colliding with each other or from pulsating stars in our Galaxy that produce antimatter. New results in studies have shown a excess of high-energy positron, the anti-particle opposite to the electron as high-energy antiprotons might be a unique signature of dark matter