A. Marini, Regularity theory for the generalized Neumann problem for Yang-Mills Connections - Non-trivial examples in dimensions 3 and 4, MATH ANNAL, 317(1), 2000, pp. 173-193
We develop the existence acid regularity theory fur the generalized Neumann
problem for Yang-Mills: connections. This is the most general boundary val
ue problem for connections on a compact manifold with smooth boundary, with
geometric meaning. It is obtained by reflecting the base manifold across i
ts boundry and lifting this action non-trivially to the bundle. The proscri
bed lifting corresponds to a geometric invariant, which is similar to the m
onopole number. When this invariant is non-zero, there exist non-trivial so
lutions of the generalized Neumann problem. We Drove the existence of non-t
rivial solutions over the 3-dimensional disk D-3 and over the 4-dimensional
manifold D-3 x S-1. We outline the procedure for finding non-trivial examp
les of solutions over more general manifolds: of dimension 3 and 4.