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A key result in computational 3-manifold topology is that any two triangulations of the same 3-manifold are connected by a finite sequence of bistellar flips, also known as Pachner moves. One limitation of this result is that little is known about the structure of this sequences; knowing more about the structure could help both proofs and algorithms. Motivated by this, we show that there must be a sequence that satisfies a rigid property that we call semi-monotonicity. We also study this result empirically: we implement an algorithm to find such semi-monotonic sequences, and compare their characteristics to less structured sequences, in order to better understand the practical and theoretical utility of this result.
A typical census of 3-manifolds contains all manifolds (under various constraints) that can be triangulated with at most n tetrahedra. Al- though censuses are useful resources for mathematicians, constructing them is difficult: the best algorithms to
In this paper, we explore minimal contact triangulations on contact 3-manifolds. We give many explicit examples of contact triangulations that are close to minimal ones. The main results of this article say that on any closed oriented 3-manifold the
It is well known that a triangulation of a closed 2-manifold is tight with respect to a field of characteristic two if and only if it is neighbourly; and it is tight with respect to a field of odd characteristic if and only if it is neighbourly and o
We construct topological triangulations for complements of $(-2,3,n)$-pretzel knots and links with $nge7$. Following a procedure outlined by Futer and Gueritaud, we use a theorem of Casson and Rivin to prove the constructed triangulations are geometr
We show that $O(n^2)$ exchanging flips suffice to transform any edge-labelled pointed pseudo-triangulation into any other with the same set of labels. By using insertion, deletion and exchanging flips, we can transform any edge-labelled pseudo-triang