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Non-trivial links and plats with trivial Gassner matrices

Published online by Cambridge University Press:  24 October 2008

Tim D. Cochran
Affiliation:
Mathematics Department, Rice university, P.O. Box 1892, Houston, Texas 77251-1892, USA

Extract

Let Bn denote the Artin braid group on ‘n-strings[ and PBn its normal subgroup consisting of all the pure braids [Bi, Mo]. These groups have been considerably scrutinized by both topologists and algebraists [BL]. One question whose answer has so far eluded us is whether or not the Gassner representation G: PBnMn × n(λ), into the group of n-by-n matrices over , is faithful (see Section 1) [Bi; ·3] [Ga]. Recently the less discriminating Burau representation B: PBnMn × n(Z[t±1] ) was shown to have a non-trivial kernel for each n ≥ 6 [M, LP] but these techniques have not yet yielded an element of kernel(G). This paper is a partial step in that direction.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1996

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