Confinement is the physics phenomenon that quarks cannot be isolated. The color-charged quarks are confined with other quarks by the strong interaction to form pairs or triplets so that the net color is neutral. The force between quarks increases as the distance between them increases, so no quarks can be found individually.
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As of the census of 2000, there are 19,701 people, 6,700 households, and 5,011 families residing in the town. The population density is 1,549.2/km² ...