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Interacting Fields, Quantum Electrodynamics
Physics — Quantum Mechanics · quantization-radiation-field-energy-momentum-tensor
Problem Calculate the energy--momentum tensor for the radiation field. Show that the normal ordered momentum operator has the form
P = : ∫ d 3 x E × B : = ∑ k , λ k a k λ † a k λ . \mathbf{P} = :\int d^3x\, \mathbf{E}\times\mathbf{B}:
= \sum_{\mathbf{k},\lambda} \mathbf{k}\, a^\dagger_{\mathbf{k}\lambda} a_{\mathbf{k}\lambda}. P =: ∫ d 3 x E × B := k , λ ∑ k a k λ † a k λ . Browse the problem library