Datum:
Die, 15/10/2024 - 11:45 - 13:00
A result of Cerf says that, for a compact, smooth 3-manifold Y , the inclusion induced map
Diff(Y) -> Homeo(Y) is a homotopy equivalence. There is an analogous inclusion induced
map for certain 'block' analogues of Diff(Y) and Homeo(Y), which are spaces defined as
realisations of certain simplicial spaces whose 1-simplices are pseudo-isotopies of Y.
Is this also a homotopy equivalence?
If it is not, what can be said about its connectivity? I will report on recent in-progress work
towardsunderstanding these questions, and their relation to 4-manifolds.
