G. Quarks

In 1810, John Dalton suggested that atoms were indivisible. That understanding of atomic structure lasted for the balance of the 19th century until J.J. Thomson identified cathode rays to consist of particles smaller than hydrogen ions. Millikan had determined the fundamental charge on the atom to be no more that 1.6 x 10^-19 C. He could not show that it was any less. By 1932, nuclear scientists has identified three constituent parts for atoms--protons, neutrons and electrons. Still, the nagging question remained: Do these particles have constituent parts?

By 1964, Murray Gell-Mann suggested yes, and speculated on the existence of quarks, particles with fractional charges of 1/3 or 2/3. The hunt has been on ever since for these elusive particles of which there are six. Read more about quarks at these and other sites.


 This site is good. Must visit


 Where Are the Quarks?
Why Don't Protons Decay?
A New Particle Zoo
The World's Biggest Microscope
Tomorrow's Elementary Particles




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last edited 12/29/05