2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/50074At first, we discuss parallels electric and magnetic fields solutions in a gravitational background. Then, considering eletromagnetic and gravitational waves symmetries we show a particular solution for stationary gravitational waves. Finally we consider gravitation as a gauge theory (effective gravitational theory), evaluate the propagators of the model, analyze the corresponding quantum excitations and verify (confirm) the tree-level unitarity at many places of the model.13 pages, AMStexHigh Energy Physics - TheoryGeneral Relativity and Quantum Cosmologytext