We investigate contrasting behaviours emerging when studying foliations on
non-metrisable manifolds. It is shown that Kneser's pathology of a manifold
foliated by a single leaf cannot occur with foliations of dimension-one. On the
other hand, there are open surfaces admitting no foliations.
Manifolds have uses throughout and beyond Mathematics and it is not
surprising that topologists have expended a huge effort in trying to understand
them. In this article we are particularly interested in the question: `when is
a manifold metrisable?' We describe many conditions equivalent to
metrisability.
Manifolds have uses throughout and beyond Mathematics and it is not
surprising that topologists have expended a huge effort in trying to understand
them. In this article we are particularly interested in the question: `when is
a manifold metrisable?' We describe many conditions equivalent to
metrisability.
We investigate the mapping class group of an orientable $\omega$-bounded
surface. Such a surface splits, by Nyikos's Bagpipe Theorem, into a union of a
bag (a compact surface with boundary) and finitely many long pipes. The
subgroup consisting of classes of homeomorphisms fixing the boundary of the bag
is a normal subgroup and is a homomorphic image of the product of mapping class
groups of the bag and the pipes.