Color singlet game
Combine quark colors and anticolors to explore meson, baryon and antibaryon components.
About this tool
Choose two or three quarks or antiquarks. Free play updates the answer immediately. Repeated selections are allowed; click a selected particle to remove it. The quiz asks for meson, baryon, antibaryon, meson and baryon components in that order. Select Check to submit one answer per round, then advance. A wrong answer resets the streak. Changing mode or starting a new quiz begins a fresh game.
Color is a charge label. R, G and B do not describe visible light; barred symbols denote the corresponding anticolors. A matching selection is a basis component of a color singlet. It is not by itself the complete singlet quantum state.
A normalized meson color singlet is (|R R̄⟩ + |G Ḡ⟩ + |B B̄⟩) / √3. A normalized baryon color singlet is (|RGB⟩ + |GBR⟩ + |BRG⟩ − |RBG⟩ − |GRB⟩ − |BGR⟩) / √6. The corresponding antibaryon state is (|R̄ḠB̄⟩ + |ḠB̄R̄⟩ + |B̄R̄Ḡ⟩ − |R̄B̄Ḡ⟩ − |ḠR̄B̄⟩ − |B̄ḠR̄⟩) / √6. The three or six terms are orthogonal basis states, which explains the normalization factors.
The order of slots matters in these quantum expressions: the baryon sums have alternating signs. The game checks only whether the selected colors can occur in one of those terms, so rearranging a selection does not change its answer. The optional complete-singlet view shows this normalized reference superposition and highlights the selected basis term, including its sign. It does not prepare a quantum state or calculate flavor, mass, binding energy or the full range of hadrons. More than three particles is outside this game, not a general prohibition in physics.
Only the mode and chosen particles are retained when local tool-input storage is enabled. Quiz answers, scores and progress are not saved. Reload or remount starts the first round with the chosen particles still present. Legacy game states migrate their input choices only.
Source: Harald Fritzsch, The history of QCD, CERN Courier (2012), for color indices and singlet states. Its historical discussion is not a statement about the current experimental status of exotic hadrons.