The Quantum Theory of Radiation

4-vector absorbed according amplitudes angle annihilation atom Born's approximation Bremsstrahlung calculated charge classical theory collisions commutation relations component Compton scattering consider Coulomb curves denotes density Dirac direction of polarization emitted energy and momentum energy loss external field factor field strengths formula free electron frequency given gives Hamiltonian high energies initial insert integral interaction intermediate k₁ Klein-Nishina formula light quantum light wave line breadth Lorentz Lorentz transformation matrix elements mc² measurement negative electron negative energy non-relativistic nucleus number of light obtain order of magnitude P. A. M. Dirac pair pair production Phys plane waves positive electron potential Proc quanta quantization quantum electrodynamics quantum mechanics quantum theory radiation oscillators region relativistic represents right-hand side second term self-energy self-force shower subsection summation test body tion total number transition probability uncertainty relation vector velocity wave function wave-length y-rays zero