Solid Torus

In mathematics, a solid torus is a topological space homeomorphic to, i.e. the cartesian product of the circle with a two dimensional disc endowed with the product topology. The solid torus is a connected, compact, orientable 3-dimensional manifold with boundary. The boundary is homeomorphic to, the ordinary torus.

A standard way to picture a solid torus is as a toroid, embedded in 3-space.

Since the disk is contractible, the solid torus has the homotopy type of . Therefore the fundamental group and homology groups are isomorphic to those of the circle:

H_k(S^1 \times D^2) \cong H_k(S^1) \cong
\begin{cases}
\mathbb{Z} & \mbox{ if } k = 0,1 \\
0 & \mbox{ otherwise }
\end{cases}.

Famous quotes containing the word solid:

    As groceries in a pantry gleam and smile
    Because they are important weights
    Bought with the metal minutes of your pay,
    So do these hours stand in solid rows,
    The dowry for a use in common life.
    Karl Shapiro (b. 1913)