activity
20072012
most citedAlgorithmically detecting the bridge number of hyperbolic knots

10 citations · 24 across the 7 of their papers we have counts for

collaborators

7 papers

math.GT2012

Computing closed essential surfaces in knot complements

Benjamin A. Burton, Alexander Coward, Stephan Tillmann

We present a new, practical algorithm to test whether a knot complement contains a closed essential surface. This property has important theoretical and algorithmic consequences; h…

math.GT2012

Crossing changes and circular Heegaard splittings

Alexander Coward

We use technology from sutured manifold theory and the theory of Heegaard splittings to relate genus reducing crossing changes on knots in S^3 to twists on surfaces arising in circ…

math.GT2012★ 4 cited

Topological and physical knot theory are distinct

Alexander Coward, Joel Hass

Physical knots and links are one-dimensional submanifolds of R^3 with fixed length and thickness. We show that isotopy classes in this category can differ from those of classical k…

math.GT2011★ 1 cited

An upper bound on Reidemeister moves

Alexander Coward, Marc Lackenby

We provide an explicit upper bound on the number of Reidemeister moves required to pass between two diagrams of the same link. This leads to a conceptually simple solution to the e…

math.GT2009★ 9 cited

Ordering the Reidemeister moves of a classical knot

Alexander Coward

We show that any two diagrams of the same knot or link are connected by a sequence of Reidemeister moves which are sorted by type.

math.GT2008

Unknotting genus one knots

Alexander Coward, Marc Lackenby

For any knot with genus one and unknotting number one, other than the figure-eight knot, we prove that there is exactly one way to unknot it by means of a crossing change. In the c…