Portal:Mathematics/Featured article/2006 43
{{Portal:Mathematics/box-header|Article of the week|{{FULLPAGENAME}}}} A manifold is an abstract mathematical space in which every point has a neighborhood which resembles Euclidean space, but in which the global structure may be more complicated. In discussing manifolds, the idea of dimension is important. For example, lines are one-dimensional, and planes two-dimensional. In a one-dimensional manifold (or one-manifold), every point has a neighborhood that looks like a segment of a line. Examples of one-manifolds include a line, a circle, and two separate circles. In a two-manifold, every point has a neighborhood that looks like a disk. Examples include a plane, the surface of a sphere, and the surface of a torus. Manifolds are important objects in mathematics and physics because they allow more complicated structures to be expressed and understood in terms of the relatively well-understood properties of simpler spaces. |align=left|...Archive |align=center| |align=right|Read more...style="float: right; margin-left: 1em; background-color: transparent; " 175px width=175 style="font-size: 85%; text-align: center; " | The four charts each map part of the circle to an open interval, and together cover the whole circle. width="100%" border="0" style="clear:both; padding:0; margin:0; background:transparent;"
