The former describes the world of electrons, quarks and so on, and led to the Standard Model.
Hadrons (i.e. particles made from quarks; including baryons like neutrons and protons) were only allowed to form 10-6 seconds after the Big Bang.
A proton contains three charged quarks bound by the strong force and its radius is defined as the distance at which the charge density drops below a certain value.
In other words, particles such as leptons and quarks have no substructure.
We streak like superheroes past suns and solar systems, we divethrough shoals of quarks and atomic nuclei.
Scientists announced Monday that in a quark-gluon plasma, achieved by smashing gold nuclei together at 99.995 percent of light speed, quarks briefly lost their ability to tell right from left.
Information flows everywhere, through wires and genes, through brain cells and quarks.
No doubt, in the future, these agents will acquire some sub-sub atomic label; just as, presumably, whole classes of angels have been replaced by photons and quarks.
As protons or heavy nuclei, such as gold, are accelerated to nearly the speed of light, the quarks and gluons inside flatten into a pancakelike structure, a relativistic effect called Lorentz contraction.
What if the earliest particles to form — such as quarks — had slightly different masses than we measure today?
Perhaps partons or quarks will be found with this accelerator.
We find that the spontaneous breaking of gauge symmetry and supersymmetry can be realized, but it is difficult to make the quarks and leptons to acquire small masses.
Then there are neutrinos, W and Z bosons, the electron-like muon and tau particles, and gluons—which hold quarks together in groups.
Last year, the venerable two-mile-long linear accelerator, where charmed quarks were discovered, was converted into a new kind of powerful laser that will create super-brilliant X-ray pulses.
The nuclei and their constituent protons and neutrons literally melt, and many more quarks, antiquarks (antimatter opposites of the quarks) and gluons are created from all the energy available.
A quark cannot exist on its own, but must be bound to other quarks or an antiquark.
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