Abstract
We prove a type of the Lefschetz hyperplane section theorem on \({\mathbb{Q}\,}\) -Fano 3-folds with Picard number one and \({\frac{1}{2}(1,1,1)}\) -singularities by using some degeneration method. As a byproduct, we obtain a new example of a Calabi–Yau 3-fold X with Picard number one whose invariants are
where H X , e(X) and c 2(X) are an ample generator of Pic(X), the topological Euler characteristic number and the second Chern class of X respectively.
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Lee, NH. A type of the Lefschetz hyperplane section theorem on \({\mathbb{Q}\,}\) -Fano 3-folds with Picard number one and \({\frac{1}{2}(1,1,1)}\) -singularities. Geom Dedicata 159, 41–49 (2012). https://doi.org/10.1007/s10711-011-9644-6
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DOI: https://doi.org/10.1007/s10711-011-9644-6