Transactions of the American Mathematical Society

Author(s): Frank Sottile; Thorsten Theobald
Journal: Trans. Amer. Math. Soc. 354 (2002), 4815-4829.
MSC (2000): Primary 14N10, 14P99, 51N20, 52A15, 68U05
Posted: June 5, 2002
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Abstract: We show that for $n \ge 3$ there are $3 \cdot 2^{n-1}$ complex common tangent lines to

general spheres in $\mathbb{R}^n$ and that there is a choice of spheres with all common tangents real.

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Frank Sottile
Affiliation: Department of Mathematics, University of Massachusetts, Lederle Graduate Research Tower, Amherst, Massachusetts 01003
Email: sottile@math.umass.edu

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