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Every connected sum of lens spaces is a real component of a uniruled algebraic variety

Johannes Huisman·Frédéric Mangolte
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Abstract

Let M be a connected sum of finitely many lens spaces, and let N be a connected sum of finitely many copies of S^1xS^2. We show that there is a uniruled algebraic variety X such that the connected sum M#N of M and N is diffeomorphic to a connected component of the set of real points X(R) of X. In particular, any finite connected sum of lens spaces is diffeomorphic to a real component of a uniruled algebraic variety.

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Johannes Huisman, Frédéric Mangolte. 2005-03-18. Every connected sum of lens spaces is a real component of a uniruled algebraic variety. https://arxiv.org/abs/math/0412159

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