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Color charge is a property of quarks and gluons that is related to the particles' strong interactions in the theory of quantum chromodynamics (QCD). Note that the "color charge" of quarks and gluons is completely unrelated to visual perception of color. The term ''color'' became popular simply because the charge responsible for the strong force between particles, can be analogized to the three primary colors of human vision: red, green, and blue.〔Close (2007)〕 Another color scheme is "red, yellow, and blue", using paint, rather than light as the perceptible analogy. Particles have corresponding antiparticles. A particle with red, green, or blue charge has a corresponding antiparticle in which the color charge must be the anticolor of red, green, and blue, respectively, for the color charge to be conserved in particle-antiparticle creation and annihilation. Particle physicists call these antired, antigreen, and antiblue. All three colors mixed together, or any one of these colors and its complement (or negative), is "colorless" or "white" and has a net color charge of zero. Free particles have a color charge of zero: baryons are composed of three quarks, but the individual quarks can have red, green, or blue charges, or negatives; mesons are made from a quark and antiquark, the quark can be any color, and the antiquark will have the negative of that color. This color charge differs from electromagnetic charges since electromagnetic charges have only one kind of value. Positive and negative electrical charges are the same kind of charge as they only differ by the sign. Shortly after the existence of quarks was first proposed in 1964, Oscar W. Greenberg introduced the notion of color charge to explain how quarks could coexist inside some hadrons in otherwise identical quantum states without violating the Pauli exclusion principle. The theory of quantum chromodynamics has been under development since the 1970s and constitutes an important component of the Standard Model of particle physics. ==Red, green, and blue== In QCD, a quark's color can take one of three values or charges, red, green, and blue. An antiquark can take one of three anticolors, called antired, antigreen, and antiblue (represented as cyan, magenta and yellow, respectively). Gluons are mixtures of two colors, such as red and antigreen, which constitutes their color charge. QCD considers eight gluons of the possible nine color–anticolor combinations to be unique; see ''eight gluon colors'' for an explanation. The following illustrates the coupling constants for color-charged particles: Image:Quark_Colors.svg|The quark colors (red, green, blue) combine to be colorless Image:Quark_Anticolors.svg|The quark anticolors (antired, antigreen, antiblue) also combine to be colorless Image:QCD Intermediate 1.png|A hadron with 3 quarks (red, green, blue) before a color change Image:QCD Intermediate 2.png|Blue quark emits a blue-antigreen gluon Image:QCD Intermediate 3.png|Green quark has absorbed the blue-antigreen gluon and is now blue; color remains conserved File:Neutron QCD Animation.gif|An animation of the interaction inside a neutron. The gluons are represented as circles with the color charge in the center and the anti-color charge on the outside. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Color charge」の詳細全文を読む スポンサード リンク
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