A New Way to Represent Links. One-Dimensional Formalism and Untangling Technology |
| |
Authors: | I A Dynnikov |
| |
Institution: | (1) Department of Mechanics and Mathematics, Moscow State University, Moscow, 119899, Russia |
| |
Abstract: | An alternative link representation different from planar diagrams is discussed. Isotopy classes of unordered nonoriented links are realized as central elements of a monoid presented explicitly by a finite number of generators and relations. The group presented by two generators and three relations a,b],a
2
ba
–2]=a,b],b
2
ab
–2]=a,b],a
–1,b
–1]]=1, where x,y]=xyx
–1
y
–1, is proved to have a commutator subgroup isomorphic to the braid group on infinitely many strands. A new partial algorithm for unknot recognition is constructed. Experiments show that the algorithm allows the untangling of unknots whose planar diagram has hundreds of crossings. Here 'untangling' means 'finding an isotopy to the circle'. |
| |
Keywords: | link representation isotopy knot theory |
本文献已被 SpringerLink 等数据库收录! |
|