Deformations of Fuchsian equations and logarithmic connections

dc.creatorSzabo, Szilard
dc.date2007-03-08
dc.date2008-01-16
dc.date.accessioned2026-07-07T08:54:41Z
dc.date.available2026-07-07T08:54:41Z
dc.descriptionWe give a geometric proof to the classical fact that the dimension of the deformations of a given generic Fuchsian equation without changing the semi-simple conjugacy class of its local monodromies (``number of accessory parameters'') is equal to half the dimension of the moduli space of deformations of the associated local system. We do this by constructing a weight 1 Hodge structure on the infinitesimal deformations of logarithmic connections, such that deformations as an equation correspond to the $(1,0)$-part. This answers a question of Nicholas Katz, who noticed the dimension doubling mentioned above. We then show that the Hitchin map restricted to deformations of the Fuchsian equation is a one-to-one etale map. Finally, we give a positive answer to a conjecture of Ohtsuki about the maximal number of apparent singularities for a Fuchsian equation with given semisimple monodromy, and define a Lagrangian foliation of the moduli space of connections whose leaves consist of logarithmic connections that can be realised as Fuchsian equations having apparent singularities in a prescribed finite set.
dc.description38 pages, content substantially improved, new results and applications added
dc.identifierhttps://arxiv.org/abs/math/0703230
dc.identifierhttp://arxiv.org/abs/math/0703230
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/146024
dc.subjectAlgebraic Geometry
dc.subjectClassical Analysis and ODEs
dc.subject14H60; 34M35; 32G34
dc.titleDeformations of Fuchsian equations and logarithmic connections
dc.typetext

Files

Collections