2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/35385After reviewing the context in which Euclidean propagation is useful we compare and contrast Euclidean and Lorentzian Maxwell-Einstein theory and give some examples of Euclidean solutions.8 pages, to appear in L. Witten FestschriftGeneral Relativity and Quantum Cosmologytext