Knot Group Epimorphisms, II

Daniel S. Silver; Wilbur Whitten

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arXiv · 0806.3223

Knot Group Epimorphisms, II

Daniel S. Silver·Wilbur Whitten

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Abstract

We consider the relations $\ge$ and $\ge_p$ on the collection of all knots, where $k \ge k'$ (respectively, $k \ge_p k'$) if there exists an epimorphism $πk \to πk'$ of knot groups (respectively, preserving peripheral systems). When $k$ is a torus knot, the relations coincide and $k'$ must also be a torus knot; we determine the knots $k'$ that can occur. If $k$ is a 2-bridge knot and $k \ge_p k'$, then $k'$ is a 2-bridge knot with determinant a proper divisor of the determinant of $k$; only finitely many knots $k'$ are possible.

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Daniel S. Silver, Wilbur Whitten. 2008-06-19. Knot Group Epimorphisms, II. https://arxiv.org/abs/0806.3223

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