Maxwell and Schrödinger -- Lorentz, Pauli and Dirac -- Quantum Fields and Particles -- Scattering and Bound States -- Hyperfine Shifts, Radiation, Quarks.In this book, quantum mechanics is developed from the outset on a relativistic basis, using the superposition principle, Lorentz invariance and gauge invariance. Nonrelativistic quantum mechanics as well as classical relativistic mechanics ap…