====== Quarks ======

Following theoretical calculations, particle accelerator experiments in the 1970s confirmed that quarks are responsible for the internal structure of protons and neutrons. ( 3 quarks each, in different configurations, see :[[content:physics:quantum_physics:electron_quark_balence]]).

Again, as calculations predicted, six 'flavours' of quark have now been experimentally identified (ref. [[http://en.wikipedia.org/wiki/Quarks|Wikipedia]] ), suggesting the obvious question, are quarks themselves formed from even more elementary particles?

Hypothetical sub-quark particles, given the name //'Preons ' //in 1974, have been proposed as possible building-blocks for quarks. Some researchers maintain that they could help provide theoretical support for experimental findings.  But, as yet, no experiment has confirmed (or refuted) their existence. See : [[https://en.wikipedia.org/wiki/Preon|Wikipedia]]

If quarks //can// be broken down, experiments underway at CERN's  [[http://en.wikipedia.org/wiki/Large_Hadron_Collider|Large Hadron Collider]] may show their finer structure. Until then, the consensus is that they appear to be fundamental - in the same way that electrons and photons appear to be.

//Note :// As well as the ubiquitous protons and neutrons which quarks can form, there are also dozens of other possible theoretical combinations for 'exotic' hadron particles - at least 66 of which have now been experimentally observed at CERN's Large Hadron Collider ([[https://www.nikhef.nl/~pkoppenb/particles.html|ref.]]).

It's a given that they are highly unstable and short-lived, if they weren't they would almost certainly be found in the natural environment.

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