Knot Concordance and Torsion
نویسنده
چکیده
The classical knot concordance group, C1, was defined in 1961 by Fox [F]. He proved that it is nontrivial by finding elements of order two; details were presented in [FM]. Since then one of the most vexing questions concerning the concordance group has been whether it contains elements of finite order other than 2–torsion. Interest in this question was heightened by Levine’s proof [L1, L2] that in all higher odd dimensions the knot concordance group contains an infinite summand generated by elements of order 4. In our earlier work studying this problem we proved the following [LN]:
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