An Injectivity Theorem for Casson-gordon Type Representations Relating to the Concordance of Knots and Links
نویسندگان
چکیده
In the study of homology cobordisms, knot concordance and link concordance, the following technical problem arises frequently: let π be a group and let M → N be a homomorphism between projective Z[π]-modules such that Zp⊗Z[π]M → Zp⊗Z[π]N is injective; for which other right Z[π]-modules V is the induced map V ⊗Z[π] M → V ⊗Z[π] N also injective? Our main theorem gives a new criterion which combines and generalizes many previous results.
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