On irregular links at infinity of algebraic plane curves
نویسنده
چکیده
We give two proofs of a conjecture of Neumann [N1] that a reduced algebraic plane curve is regular at infinity if and only if its link at infinity is a regular toral link. This conjecture has also been proved by Ha H. V. [H] using Lojasiewicz numbers at infinity. Our first proof uses the polar invariant and the second proof uses linear systems of plane curve singularities. The second approach also proves a stronger conjecture of [N1] describing topologically the regular link at infinity associated with an irregular link at infinity.
منابع مشابه
Knot theory of complex plane curves
The primary objects of study in the “knot theory of complex plane curves” are C-links: links (or knots) cut out of a 3-sphere in C2 by complex plane curves. There are two very different classes of C-links, transverse and totally tangential. Transverse C-links are naturally oriented. There are many natural classes of examples: links of singularities; links at infinity; links of divides, free div...
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