Introduction
This page will introduce readers with little knowledge of sub-nuclear particle physics, to some of the basic and most important concepts. As a simplified introductory guide, that will not deal with more complex issues or theories;
but it will help explain the scientific principles as used in the trilogy.
This is how the basics fit together. Let's begin with the building blocks: The current Standard Model of Elementary Particles, pictured right, shows seventeen of the known particles, which at last count numbered twenty-seven.
Neutrons and protons (both composed of quarks), comprise the nucleus of an atom, which is orbited by one or many electrons, which are leptons. Neutrons and protons are called hadrons - Greek for heavy. They are composed of quarks.
Quarks are elementary particles that have fractional electric charge - either 1/3rd or 2/3rd the charge of the electron.
Quarks feel the strong nuclear force transmitted by gluons. This force is unusual because its effects get stronger the more you try and pull quarks apart. Most forces like gravity are weaker the further apart the interacting particles
- inverse square law etc.
So two consequences:
(1) Quarks seldom exist alone, they always come in pairs, or more - as you try and separate them the energy (and mass) of their interaction becomes so great that quark pairs are generated that pair off to lower the energy of the
system. So you never normally find quarks by themselves.
(2) Neither do you find fractional electric charges in nature - so either you have two bound quarks of opposite charge +1/3e and -1/3e that cancel out to give a neutral particle, or three bound quarks +1/3e + 1/3e +1/3e (or the
negative equivalent) to give particles of charge +1 or -1, or three quarks (+2/3e - 1/3e-1/3e) to give particles of charge 0.
Neutrons are bound systems of 3 quarks with net electric charge zero, composed of a down-up-down quarks. Protons are bound systems of 3 quarks with net electric charge +1, composed of up-down-up quarks.
Heavier quarks are unstable and decay to lower mass quarks - that's why a neutron alone outside the atomic nucleus will decay into a proton, anti-electron, and neutrino with a half-life of around 15 seconds. In comparison the experimental
lower bound on the half-life of the proton is about 10^33 years.
Systems of two bound quarks are called mesons. The chi-boson is a meson composed of a bottom and anti-bottom quark. Bottom quarks are quite massive, so creating them takes a lot of energy; an LHC scale machine is required. So this
announcement is not unexpected - just nice to see.
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