The rack space
Abstract
The main result of this paper is a new classification theorem for links (smooth embeddings in codimension 2). The classifying space is the rack space (defined in [Trunks and classifying spaces, Applied Categorical Structures, 3 (1995) 321--356]) and the classifying bundle is the first James bundle (defined in "James bundles" math.AT/0301354). We investigate the algebraic topology of this classifying space and report on calculations given elsewhere. Apart from defining many new knot and link invariants (including generalised James--Hopf invariants), the classification theorem has some unexpected applications. We give a combinatorial interpretation for \pi_2 of a complex which can be used for calculations and some new interpretations of the higher homotopy groups of the 3--sphere. We also give a cobordism classification of virtual links.
Cite
@article{arxiv.math/0304228,
title = {The rack space},
author = {Roger Fenn and Colin Rourke and Brian Sanderson},
journal= {arXiv preprint arXiv:math/0304228},
year = {2007}
}
Comments
This paper is largely extracted from our January 1996 preprint `James bundles and applications' available at http://www.maths.warwick.ac.uk/~cpr/ftp/james.ps Version 2: minor corrections