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4:00 pm Monday, October 6, 2008 Topology Seminar: Higher-order analogues of the p-primary decomposition of the algebraic knot concordance groupby Tim Cochran (Rice University) in HB 427- We develop new classification results for certain cyclic modules over noncommutative rings and apply these to show that the knot concordance group splits up into many more large disjoint pieces than previously previously known, contributing to a fractal nature in the set of concordance classes. The pieces are essentially distinguished by having "relatively prime" higher-order Alexander polynomials. The fact that this sentence makes no good sense over non-UFD's is one of the things that makes this hard. This is joint work with S. Harvey and C. Leidy.
Submitted by shelly@rice.edu |