Events

Date: 28 May 2025   Time: 14:00 - 15:00

Location: MB503

The Bianchi type VI_{-1/9}, VIII and IX vacuum models all have 4-dimensional Hubble-normalized state spaces and are expected to have a generic initial oscillatory singularity, but the invariant boundary sets responsible for the oscillations are much more complicated for type VI_{-1/9} than those of type VIII and IX. For the first time, we explicitly solve the equations on these type VI_{-1/9} boundary sets and also introduce a new graphic representation of the associated network of heteroclinic chains (i.e. sequences of solutions describing the oscillations). In particular, we give examples of networks of entangled cyclic heteroclinic chains and show that only some of these cyclic heteroclinic chains are asymptotically relevant.