It is not known whether
there exists a computable function bounding the number of Pachner moves needed to
connect any two triangulations of a compact 3-manifold. In this paper we find an
explicit bound of this kind for all Haken 3-manifolds that contain no fibred
submanifolds as strongly simple pieces of their JSJ-decomposition. The explicit
formula for the bound is in terms of the number of tetrahedra in the two
triangulations. This implies a conceptually trivial algorithm for recognising any
nonfibred knot complement among all 3-manifolds.
Department of Pure Mathematics and
Mathematical Statistics
Center for Mathematical Sciences
University of Cambridge
Wilberforce Road
Cambridge, CB3 0WB
United Kingdom