Matter-Antimater Asymmetry

What is Antimatter? That stuff that propels the Enterprise across the stars in "Star Trek really exists. It is helpful, however, to understand the Standard Model of Particle Physics in order to define antimatter. All matter is made up of atoms, which are made up of Baryons and Leptons. Baryons, particles like protons(p+) and neutrons(n), are massive and are made up of even smaller particles called quarks (up, down, strangeness, charmed, top and bottom). For instance, a proton is made up of an up and two downs(udd). Quarks are held together by the strong nuclear force which is carried by a Gauge Boson called a Gluon. Leptons, particles like electrons(e-), are basic particles in themselves. Each quark has a charge(Q), a baryon number(B), and a color which isn,t really a color, just a classification. Similarly, each lepton has a charge(Q) and a lepton number(L). The color of a lepton, however, is always white.
Each quark and lepton has an antiparticle. An antiparticle has the same mass as normal particle, but the charge is reversed as is the magnetic moment. For example, a positron(e+) has the same mass as an electron(e-), but a charge of (+1) instead of (-1). These antiquarks( antiup, antidown, anticharmed...etc.) can be combined like quarks to form antibaryons: like antiprotons(p-) and antineutrons(n-). As mentioned above, a proton is made of one up quark and two down quarks(udd). An antiproton, is therefore made up of one antiup quark and two antidown quarks(u-d-d-).

When antimatter and matter come into contact, they annihilate each other and create two photons: p*(p-) -->two photons. In any reaction between particles, anti or normal, the baryon and lepton numbers must be conserved. In other words, the total baryon and lepton number of the reactants must equal the total baryon and lepton number of the products. There is a problem with the Standard Model, however.