Parity condition for irreducibility of Heegaard splittings
arXiv:0812.0225
Abstract
Casson and Gordon gave the rectangle condition for strong irreducibility of Heegaard splittings [1]. We give a parity condition for irreducibility of Heegaard splittings of irreducible manifolds. As an application, we give examples of non-stabilized Heegaard splittings by doing a single Dehn twist.
arXiv commentThe paper is totally rewritten. The title has been changed. 9 pages, 5 figures