[see also: neat]
Neighbourhoods of points in these spaces appear at first glance to have a nice regular structure, but upon closer scrutiny, one sees that many neighbourhoods contain collections of arcs hopelessly folded up.
In the case of $M_n$, the corresponding symmetric group action on cohomology is particularly nice.
Homogeneous spaces are, in a sense, the nicest examples of Riemannian manifolds.
Go to the list of words starting with: a b c d e f g h i j k l m n o p q r s t u v w y z