What is Matter?

Matter is what all life is made of. Me, you, and everything around is made up of matter. Matter is any object that occupies physical space and possesses a rest mass (has inerita). The idea of matter and atoms was first thought of in ancient Greece. Greek philosopher Leucippus of Miletus believed in 5th century BCE that everything was made up of objects too small to be seen. What they did not know at this time was that atoms were actually made up of something else, subatomic particles. These are very important as they are parts of the building blocks of matter. Together the electron, proton, and neutron form to become atoms, which when placed together can become molecules. These molecules are also still very small and invisible to the naked eye. Molecules must combine to form compounds. When these are all connected together into specific arrangements with certain pieces, they create different compounds. Humans contain unique arrangements to those of trees, and to those of plastics. It is important to understand what matter is, as antimatter is actually the opposite of matter. The differences which exist between matter and antimatter is not obvious to the blind eye, the differences actually exist on the subatomic level.

The Prediction

Antimatter was first discovered in 1928 by English physicist Paul Dirac. Dirac predicted the existence of antimatter when he combined quantum theory with the theory of special relativity. What Dirac was trying to do was explain the behavior of an electron moving at a relativistic speed. What Dirac discovered was that his final equation worked for both an electron with positive and negative energy. This defied all current logic as it was believed that the energy of a particle must always be positive. At first Dirac did not accept his discovery but he soon chose to embrace it, interpreting it to mean that for every particle, there must exist an antiparticle. This antiparticle was just like the normal particle, however the charge of this antiparticle would be inverted from the normal particle.

The Discovery

On August 2 1930, Carl Anderson discovered the existence of this predicted particle. Anderson’s experiment consisted of observing the trails left behind from a particle shower once cosmic rays passed through them. He noticed something strange about one particle which stood out to him. This particle had the same mass as all the other particles however it had a different charge, an opposite charge.

The Antiproton

From this we can then conclude that every electron must have an antielectron which has a positive electron. The mass and behavior of this antielectron would not differ from the normal electron. It was not until 1955 that the antiparticle for the proton was discovered. Since then it is believed that all particles have antiparticles which are equivalent in all ways except for charge. The only problem with this theory is that if this was true then an equivalent amount of matter and antimatter should have been created in the big bang, however there is next to no antimatter present in the observable universe.

Natural Creation

Antimatter can actually be found in nature as it is not only formed in labs. Antimatter can actually be found as product of radioactive decay. Not all radioactive decay forms antimatter, only beta plus decay actually creates antimatter. In this form of decay the proton in the parent nucleus decays into a neutron that will remain in the daughter nucleus. As a result the nucleus emits a positron (antielectron) and a neutrino (a different subatomic particle). Scientists believe that observing neutrinoless double-beta decay will help them understand why there is so much more matter in the observable universe than there is antimatter. When this form of decay occurs it is believed that two electrons are produced and that no antimatter is produced. This is because neutrinos are believed to be Majorna particles. These particles are different from Dirac particles as it is believed that these particles can function as both matter and antimatter. While how is this decay any different from regular beta decay? While in germanium atoms this form of decay actually happens twice. Since it is understood that matter and antimatter would annihilate themselves when they interact, physicists predict that it is possible these neutrinos destroy themselves before they can exit the atom.

Artificial Creation

Apart from natural formations of antimatter, it can also be created in a lab. The European Organization for Nuclear Research (CERN) has created certain instruments which they use to study these antiparticles. The instruments they can use to create and study antimatter include:
-Antiproton Decelerator (AD)
-Antihydrogen Experiment: Gravity, Interferometry, Spectroscopy (AEGIS
-Antihydrogen Laser PHysics Apparatus (ALPHA)
-Atomic Spectroscopy And Collisions Using Slow Antiprotons (ASACUSA)
-Antihydrogen trap (ATRAP)
-Baryon Antibaryon Symmetry Experiment
These machines all serve different purposes in the creating, storing, and study of antimatter however the creation of antimatter is a result of high-energy collisions. In these high-energy collisions the excess energy actually produces pairs of particles and their antimatter particles. An example of this is colliding a stream of high-energy protons with a dense target to produce antiprotons. It is interesting to note that while positrons and antiprotons are the only forms of antimatter created, it is possible to create an anti-atom. The issue with creating an anti-atom however is that they cannot be stored magnetically because they have no charge. As a result of this they risk destroying any form of containment which they are placed in.

The Annihilation Of Matter & Antimatter

The destruction between a particle and its antimatter opposite can generate great amounts of energy. Since the destruction of the two results in all of the mass being converted into energy, Einstein’s famous mass-energy equivalence equation shows that one kilogram of matter and one kilogram of its antimatter counterpart would actually result in an explosion which generates the same amount of energy as the largest thermonuclear bomb ever created. This is an important aspect of antimatter which can be utilized to generate many different applications.