G2-instantons with symmetry

Goncalo Oliveira
(Duke University)
Tirsdag, 4 juli, 2017, at 14:15-15:15, in Aud. G2 (1532-122)
G2-instantons, are 7-dimensional analogs of anti-self-dual connections in 4 dimensions, which however require the underlying manifold to have a G2-structure. The interest on these G2-instantons comes from the suggestion, of Donaldson and Segal, that it may be possible to use them to define enumerative invariants of G2-holonomy metrics. In the talk, I shall report on joint work with Jason Lotay where we give existence, non-existence and classification results for these instantons. In the particular case of R^4 x S^3, with it's two explicitly known distinct G2-holonomy metrics, we exhibit the different behavior of instantons. We also give an explicit example of sequences of G2-instantons where “bubbling” and “removable singularity” phenomena occur in the limit.
Organiseret af: QGM
Kontaktperson: Jørgen Ellegaard Andersen