2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/199217From appropriate expressions for effective actions, the Hawking radiation from charged black holes is derived, using only covariant boundary conditions at the event horizon. The connection of our approach with the Unruh vacuum and the recent analysis \cite{Robwilczek,Isowilczek,shailesh} of Hawking radiation using anomalies is established.Minor changes, conforms to published versionHigh Energy Physics - TheoryGeneral Relativity and Quantum Cosmologytext