523 research outputs found
The big Dehn surgery graph and the link of S^3
In a talk at the Cornell Topology Festival in 2005, W. Thurston discussed a
graph which we call "The Big Dehn Surgery Graph", B. Here we explore this
graph, particularly the link of S^3, and prove facts about the geometry and
topology of B. We also investigate some interesting subgraphs and pose what we
believe are important questions about B.Comment: 15 pages, 4 figures, 4 ancillary files. Reorganized and shortened
from previous versions, while correcting one error in the proof of Theorem
5.4. Also, ancillary files detailing our computations with the computer
program ORB have been provide
Asymmetric hyperbolic L-spaces, Heegaard genus, and Dehn filling
An L-space is a rational homology 3-sphere with minimal Heegaard Floer
homology. We give the first examples of hyperbolic L-spaces with no symmetries.
In particular, unlike all previously known L-spaces, these manifolds are not
double branched covers of links in S^3. We prove the existence of infinitely
many such examples (in several distinct families) using a mix of hyperbolic
geometry, Floer theory, and verified computer calculations. Of independent
interest is our technique for using interval arithmetic to certify symmetry
groups and non-existence of isometries of cusped hyperbolic 3-manifolds. In the
process, we give examples of 1-cusped hyperbolic 3-manifolds of Heegaard genus
3 with two distinct lens space fillings. These are the first examples where
multiple Dehn fillings drop the Heegaard genus by more than one, which answers
a question of Gordon.Comment: 19 pages, 2 figures. v2: minor changes to intro. v3: accepted
version, to appear in Math. Res. Letter
Cusp types of quotients of hyperbolic knot complements
This paper completes a classification of the types of orientable and
non-orientable cusps that can arise in the quotients of hyperbolic knot
complements. In particular, cannot be the cusp cross-section of
any orbifold quotient of a hyperbolic knot complement. Furthermore, if a knot
complement covers an orbifold with a cusp, it also covers an
orbifold with a cusp.Comment: 11 pages, 4 figures, updates to this version include a complete
classification of cusps of non-orientable quotients, minor tweaks to the
exposition, an update to the proof of Theorem 1.1 and the removal of a
discussion about the uniqueness of rigid cusp quotients of knot complemen
Poincare homology sphere, lens space surgeries, and some knots with tunnel number two
We exhibit an infinite family of knots in the Poincare homology sphere with tunnel number 2 that have a lens space surgery. Notably, these knots are not doubly primitive and provide counterexamples to a few conjectures. Additionally, we update (and correct) our earlier work on Hedden’s almost-simple knots. In the appendix, it is shown that a hyperbolic knot in the Poincare homology sphere with a lens space surgery has either no symmetries or just a single strong involution.Mathematic
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