2 papers
math.GT1999
Positive diagrams for Seifert fibered spaces
John Hempel
A Heegaard diagram for a 3-manifold M is a closed, oriented surface S together with a pair (X, Y) of compact 1-manifolds in S whose components serve as attaching curves for the 2-h…
math.GT1997
3-manifolds as viewed from the curve complex
John Hempel
A Heegaard diagram for a 3-manifold is regarded as a pair of simplexes in the complex of curves on a surface and a Heegaard splitting as a pair of subcomplexes generated by the equ…