Bengtsson & Zyczkowski in the introduction (see p14-16) to their wonderful book make use of chromaticity diagrams to motivate their study of quantum states. h

Bengtsson & Zyczkowski in the introduction (see p14-16) to their wonderful book make use of chromaticity diagrams to motivate their study of quantum states. https://www.researchgate.net/profile/Karol-Zyczkowski/publication/325707595_Geometry_of_quantum_states_An_introduction_to_quantum_entanglement/links/5e6ab206299bf12e23c03ea7/Geometry-of-Quantum-States-An-Introduction-to-Quantum-Entanglement.pdf https://www.researchgate.net/profile/Karol-Zyczkowski/public... >In a way tradition suggests that colour theory should be studied before quantum mechanics, because this is what Schroedinger was doing before inventing his wave equation.