Ragini Singhal (Humboldt University, Berlin) will talk in the geometry seminar on 02/05/2023 at 2pm in the Salle des Profs (9th floor building NO, Campus de la Plaine). Ragini’s title is “Deformation theory of nearly G2 manifolds” and her abstract is below.
I this talk we will describe the deformation theory of nearly G2 manifolds. These are seven dimensional manifolds admitting real Killing spinors. We show that the infinitesimal deformations of nearly G2 structures are obstructed in general. Explicitly, we prove that the infinitesimal deformations of the homogeneous nearly G2 structure on the Aloff–Wallach space are all obstructed to second order. We also completely describe the cohomology of nearly G2 manifolds. This talk is based on a joint work with Dr Shubham Dwivedi (Humboldt University).