Compression body
In the theory of 3-manifolds, a compression body is a kind of generalized handlebody.
A compression body is either a handlebody or the result of the following construction:
Let be a compression body. The negative boundary of C, denoted, is. The positive boundary of C, denoted, is minus the negative boundary.
There is a dual construction of compression bodies starting with a surface and attaching 2-handles to. In this case is, and is minus the positive boundary.
Compression bodies often arise when manipulating Heegaard splittings.
