Elementary particle

In particle physics, an elementary particle refers to a particle of which other, larger particles are composed. For example, atoms are made up of smaller particles known as electrons, protons, and neutrons. The proton and neutron, in turn, are composed of more elementary particles known as quarks. One of the outstanding problems of particle physics is to find the most elementary particles - or the so-called fundamental particles - which make up all the other particles found in Nature, and are not themselves made up of smaller particles.

The Standard Model of particle physics contains 12 species of elementary fermions ("matter particles") and 12 species of elementary bosons ("radiation particles"), plus their corresponding antiparticles. However, the Standard Model is widely considered to be a provisional theory rather than a truly fundamental one, and it is possible that some or all of its "elementary" particles are actually composite particles. There might also be other elementary particles not described by the Standard Model, the most prominent being the graviton, the hypothetical particle that carryies the gravitational force.

See also

• Subatomic particle
• Particle physics
• List of particles

• particleadventure.org: The Standard Model, Unsolved Mysteries. Beyond The Standard Model, What is the World Made of? The Naming of Quarks
• quarkdance.org ("Cute" dancing quarks with music)
• University of California: Particle Data Group
• particleadventure.org: Particle chart
• CERNCourier: Season of Higgs and melodrama
• 6 December, 2001, BBCNews: 'God particle may not exist Citat: "...its giant accelerator which should have shown up the presence of the Higgs found absolutely nothing - and this could mean particle physics having to revisit some of its most cherished ideas..."
• Milo Wolff: The Physical Origin of Electron Spin - using quantum wave particle structure Citat: "...The electron's structure, as well as its spin, had been a mystery. Providing a physical origin of spin for the first time is the purpose of this paper....note that spin, and other properties, are attributes of the underlying quantum space rather than of the individual particle. This is why spin, like charge, has only one value for all particles...This structure settles a century old paradox of whether particles are waves or point-like bits of matter. They are wave structures in space. There is nothing but space. As Clifford speculated 100 years ago, matter is simply, "undulations in the fabric of space". ..."
• Robert Rutkiewicz: Explaining Particle Spin
• Robert Rutkiewicz: Defining Mass Citat: "...The value of mass is not being redefined. But the concept of mass being a fundamental property is reviewed...A new physical law is postulated: All known particless are elements of momentum moving at a velocity c...This extension is based on special relativity and uses SR equation for mass..."
• The Physical Origin of Electron Spin - using quantum wave particle structure Citat: "...note that spin, and other properties, are attributes of the underlying quantum space rather than of the individual particle. This is why spin, like charge, has only one value for all particles...."
• Glimpses of a new paradigm. K.V.K. Nehru Citat: "...Dewey B. Larson introduces the new paradigm that motion is the basic and sole constituent of the physical universe, and space-time is the content—not the container—of the universe...", Dewey B. Larson (1898-1990)