日時：　　 ２００３年10月２８日（火）午後４時００分〜５時３０分
場所：　　 早稲田大学理工学部５１号館１８階１８−１２教室
　　　　　　（http://web.sci.waseda.ac.jp/campus-map/）
講演者：　William W. Menasco氏 （State University of New York at Buffalo）
題目：　　 Applications of the Markov Theorem Without Stabilization
概要：　　 This work is joint with Joan Birman. The Markov Theorem Without
Stabilization (MTWS) establishes the existence of a finite set of
moves which allow one to pass from an arbitrary closed braid
representative X+ of an arbitrary oriented knot or link type in oriented
3-space to an arbitrary representative X- of minimum braid index,
through a sequence of closed braids whose braid index is non-increasing.
Using the MTWS, we will give several constructions for producing two
transversal knots that have the same topological knot type in the 3-sphere,
have the same transversal invariants in the standard contact structure on
the 3-sphere, but are not transversally isotopic.

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