Testing families of analytic discs in the unit ball

Abstract

Let $a,b,c\in {\mathbb{C}}^2$ be three non collinear points such that their mutual joining complex lines do not intersect the unit ball ${\mathbb{B}}^2$ and such that the line through $a$ and $b$ is tangent to ${\mathbb{B}}^2$. Then the set of lines concurrent to $a,b$ and $c$ is a testing family for continuous functions on ${\mathbb{S}}^3$. This improves a result by the authors and solves a case left open in the literature as described by Globevnik.

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