This is my "geometric freshman explanation":
the problem is to put something instead of the "?" doing the job of $s$ in
alt text http://img841.imageshack.us/img841/9651/outy.png
...but the composition $\eta\circ\epsilon$ is disconnected, and there is no way to obtain a disconnected manifold starting gluing something to that. :( such a pity.
This is my "geometric freshman explanation":
the problem is to put something instead of the "?" doing the job of $s$ in
alt text http://img841.imageshack.us/img841/9651/outy.png
...but the composition $\eta\circ\epsilon$ is disconnected, and there is no way to obtain a disconnected manifold starting gluing something to that. :( such a pity.
This is my "geometric freshman explanation":
the problem is to put something instead of the "?" doing the job of $s$ in
...but the composition $\eta\circ\epsilon$ is disconnected, and there is no way to obtain a disconnected manifold starting gluing something to that. :( such a pity.
