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A classification of centrally-symmetric and cyclic 12-vertex triangulations of $S^2 \times S^2$

G. Lassmann·E. Sparla
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Abstract

In this paper our main result states that there exist exactly three combinatorially distinct centrally-symmetric 12-vertex-triangulations of the product of two 2-spheres with a cyclic symmetry. We also compute the automorphism groups of the triangulations. These instances suggest that there is a triangulation of $S^2 \times S^2$ with 11 vertices -- the minimum number of vertices required.

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BibTeXRIS

G. Lassmann, E. Sparla. 1998-12-03. A classification of centrally-symmetric and cyclic 12-vertex triangulations of $S^2 \times S^2$. https://arxiv.org/abs/math/9812024

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