Structures on M x I (Ex)
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Let $M$ be a closed oriented topological manifold of dimension $n \geq 5$ and let | Let $M$ be a closed oriented topological manifold of dimension $n \geq 5$ and let | ||
− | $\tilde \pi_0 \textup{Homeo}_+(M)$ denote the pseudo-isotopy group of orientation preserving self homeomorphisms of $M$: two self homeomorphisms $h_0$ and $h_1$ are pseudo-isotopic if | + | $\tilde \pi_0 \textup{Homeo}_+(M)$ denote the pseudo-isotopy group of orientation preserving self homeomorphisms of $M$: two self homeomorphisms $h_0$ and $h_1$ are pseudo-isotopic if they extend to a homeomorphism $F \colon M \times I \cong M \times I$: the group operation is composition. Let |
$$ \tilde \pi_0 \textup{SHomeo}_+(M) \subset \tilde \pi_0 \textup{Homeo}_+(M) $$ | $$ \tilde \pi_0 \textup{SHomeo}_+(M) \subset \tilde \pi_0 \textup{Homeo}_+(M) $$ | ||
be the subgroup of equivalences classes which are homotopic to the identity. | be the subgroup of equivalences classes which are homotopic to the identity. |
Revision as of 10:44, 30 May 2012
Let be a closed oriented topological manifold of dimension and let denote the pseudo-isotopy group of orientation preserving self homeomorphisms of : two self homeomorphisms and are pseudo-isotopic if they extend to a homeomorphism : the group operation is composition. Let
be the subgroup of equivalences classes which are homotopic to the identity.
Exercise 0.1. Using the fact that the topological surgery exact sequence is a long exact sequence of abelian groups show that is abelian.