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arXiv · 1911.08084

Primary decomposition of knot concordance and von Neumann rho-invariants

Abstract

We address the primary decomposition of the knot concordance group in terms of the solvable filtration and higher-order von Neumann $\rho$-invariants by Cochran, Orr, and Teichner. We show that for a nonnegative integer n, if the connected sum of two n-solvable knots with coprime Alexander polynomials is slice, then each of the knots has vanishing von Neumann $\rho$-invariants of order n. This gives positive evidence for the conjecture that nonslice knots with coprime Alexander polynomials are not concordant. As an application, we show that if K is one of Cochran-Orr-Teichner's knots which are the first examples of nonslice knots with vanishing Casson-Gordon invariants, then K is not concordant to any knot with Alexander polynomial coprime to that of K.

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Min Hoon Kim, Se-Goo Kim, Taehee Kim. 2019-11-19. Primary decomposition of knot concordance and von Neumann rho-invariants. https://arxiv.org/abs/1911.08084

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