Jakob Stein (IMPA Brasil) will talk in the geometry seminar on 13/10 at 2pm in the Salle des Profs (9th floor of building NO). Jakob’s title is “Nearly G2-structures and G2-Laplacian co-flows” and his abstract is below.
Nearly G2-structures in dimension seven are, up to scaling, critical points of a geometric flow called (modified) Laplacian co-flow. Moreover, since nearly G2-structures define Einstein metrics, they can also be associated to critical points of the volume-normalised Ricci flow. In this talk, we will discuss a recent joint work with Jason Lotay, showing that many of these nearly G2 critical points are unstable for the modified co-flow, and giving a lower bound on the index.