Quantization of electromagnetic field in the Schwarzschild spacetime

Abstract: We discuss the problem of canonical quantization of electromagnetic field in the Schwarzschild spacetime. It is shown that a consistent procedure of canonical quantization of the field can be carried out without taking into account the internal region of the black hole. We prove that there exists a unitary gauge, which can be viewed as a combination of the Coulomb and Poincare gauges and is compatible with the field equations. The solutions corresponding to the stationary one-particle states of the electromagnetic field are studied, the canonical commutation relations and the Hamiltonian of the quantized electromagnetic field are obtained. It is shown that the number of quantum states in the resulting theory is twice as large as the number of quantum states of the electromagnetic field in Minkowski spacetime.