Viro theorem and topology of real and complex combinatorial hypersurfaces

Ilia Itenberg; Eugenii Shustin

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arXiv · math/0105198

Viro theorem and topology of real and complex combinatorial hypersurfaces

Ilia Itenberg·Eugenii Shustin

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Abstract

We introduce a class of combinatorial hypersurfaces in the complex projective space. They are submanifolds of codimension~2 in $\C P^n$ and are topologically "glued" out of algebraic hypersurfaces in $(\C^*)^n$. Our construction can be viewed as a version of the Viro gluing theorem, relating topology of algebraic hypersurfaces to the combinatorics of subdivisions of convex lattice polytopes. If a subdivision is convex, then according to the Viro theorem a combinatorial hypersurface is isotopic to an algebraic one. We study combinatorial hypersurfaces resulting from non-convex subdivisions of convex polytopes, show that they are almost complex varieties, and in the real case, they satisfy the same topological restrictions (congruences, inequalities etc.) as real algebraic hypersurfaces.

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BibTeX RIS

Ilia Itenberg, Eugenii Shustin. 2001-08-10. Viro theorem and topology of real and complex combinatorial hypersurfaces. https://arxiv.org/abs/math/0105198

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