2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/174681Using a local construction from a previous paper, we exhibit a numerical invariant, the differential Swan conductor, for an isocrystal on a variety over a perfect field of positive characteristic overconvergent along a boundary divisor; this leads to an analogous construction for certain p-adic and l-adic representations of the etale fundamental group of a variety. We then demonstrate some variational properties of this definition for overconvergent isocrystals, paying special attention to the case of surfaces.34 pages; v3: major revisions in 3.4, 4.3, 5.x; minor changes elsewhereNumber TheoryAlgebraic Geometry11S15text