## Acta Mathematica

### Real quadrics in Cn, complex manifolds and convex polytopes

#### Abstract

In this paper, we investigate the topology of a class of non-Kähler compact complex manifolds generalizing that of Hopf and Calabi-Eckmann manifolds. These manifolds are diffeomorphic to special systems of real quadrics Cn which are invariant with respect to the natural action of the real torus (S1)n onto Cn. The quotient space is a simple convex polytope. The problem reduces thus to the study of the topology of certain real algebraic sets and can be handled using combinatorial results on convex polytopes. We prove that the homology groups of these compact complex manifolds can have arbitrary amount of torsion so that their topology is extremely rich. We also resolve an associated wall-crossing problem by introducing holomorphic equivariant elementary surgeries related to some transformations of the simple convex polytope. Finally, as a nice consequence, we obtain that affine non-Kähler compact complex manifolds can have arbitrary amount of torsion in their homology groups, contrasting with the Kähler situation.

#### Dedication

Dedicated to Alberto Verjovsky on his 60th birthday.

#### Article information

Source
Acta Math., Volume 197, Number 1 (2006), 53-127.

Dates
Revised: 3 April 2006
First available in Project Euclid: 31 January 2017

https://projecteuclid.org/euclid.acta/1485891843

Digital Object Identifier
doi:10.1007/s11511-006-0008-2

Mathematical Reviews number (MathSciNet)
MR2285318

Zentralblatt MATH identifier
1157.14313

Rights

#### Citation

Bosio, Frédéric; Meersseman, Laurent. Real quadrics in C n , complex manifolds and convex polytopes. Acta Math. 197 (2006), no. 1, 53--127. doi:10.1007/s11511-006-0008-2. https://projecteuclid.org/euclid.acta/1485891843

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