The Wonderful World of Baryons and Leptons


The in world of physicists the sub-atomic particles are divided into to distinct classes, the Baryons and Leptons. These classifications are used to create laws that become extremely important in the discovery of other sub-atomic particles. The Leptons have very small masses, these are the electrons and positrons and other particles to be discovered later. The Baryons are very massive compared to the Leptons; these are protons, neutrons, and their anti-particles. From the concept of Baryons and Leptons, physicists devised the conservation of Baryon and Lepton number. They assigned values to the various range of sub-atomic particle and then can predict what will happen in reactions with these particles using these principles. They use this idea to show why a neutron (Baryon number of +1) can become a proton (Baryon number of +1) while a proton cannot become a Positron (Baryon number 0) even while charge is conserved. The conservation of Lepton number follows the same principle.

This idea leads to the discovery of the antineutron. It was found experimentally that a proton and antiproton, if close enough to each other, could cancel charges without annahilation. Without their charges, one could suppose each was a neutron but this seemingly violated the Conservation of Baryon number. The sum of the Baryon numbers of a proton anti-proton pair is zero while the sum of the Baryon number of a pair of neutrons is +2, breaking the rule. But, if there were an antineutron with a Baryon number of -1 then the net Baryon number becomes zero and the experiment makes sense. How can something with a charge of zero have an opposite? This happens because a neutron (or antineutron) have a net charge of zero. There are localized charges over the surface of the particle so that its total charge is zero. The difference between the two is that while they both spin in the same direction, because of this arrangement, each has an opposite magnetic field.
Think about the planet Earth. The neutron would have its "North Pole" in the artic as it really it. The anti-neutron would have its "North Pole" in Antarctica.


The natural consequence of this is, "Where is all the antimatter?" If there are positrons, antiprotons, and antineutrons, why does there only seem to be normal matter around? This is a question that physicists are currently trying to solve. Theoretically there should be an equal amount of matter and antimatter. Antimatter has the same properties as normal matter in terms of reactions and the like so there should be antiatoms, antimolecules, and antisolar systems. Actually, we have made antideuterium and antihelium-3 nuclei but the search for the missing antimatter is one of the major quests of the modern physicists.
Somewhere there should hypothetically be an anti-me, anti-you, and anti-Earth.


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