Abstract: We prove that all
possible pants decompositions on compact, connected, orientable surfaces can be
obtained via a recursive procedure beginning in the low genus cases.
Second, let S
be a closed, connected, oriented surface of genus P and be pants decompositions of S,
and let be an adjacency-preserving
bijection. We prove that if P and are topologically equivalent, or if
is also adjacency-preserving, then F
restricts to bijections between two certain subcollections of curves in P
and - a condition which then implies
that either F
is induced by a homeomorphism of S, or
that P and are topologically equivalent, and
the graph corresponding to the pants decomposition is isomorphic to the complete
graph on four vertices.
The
proofs use the well-known correspondence between pants decompositions and
connected, 3-regular graphs.
Keywords and phrases: surface, pants decomposition, pants graph, adjacency.