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JOURNALS // Trudy Matematicheskogo Instituta imeni V.A. Steklova // Archive

Trudy Mat. Inst. Steklova, 2024 Volume 326, Pages 275–292 (Mi tm4401)

Bier Spheres and Toric Topology

Ivan Yu. Limonchenkoa, Matvey A. Sergeevb

a Mathematical Institute of the Serbian Academy of Sciences and Arts (SASA), Belgrade, Serbia
b National Research University Higher School of Economics, Moscow, Russia

Abstract: We compute the real and complex Buchstaber numbers of an arbitrary Bier sphere. In dimension two, we identify all the 13 different combinatorial types of Bier spheres and show that 12 of them are nerve complexes of nestohedra, while the remaining one is a nerve complex of a generalized permutohedron. As an application of our results, we construct a regular normal fan for each of those 13 Delzant polytopes, compute the cohomology rings of the corresponding nonsingular projective toric varieties, and examine the orientability of the corresponding small covers.

Keywords: Bier sphere, nestohedron, Delzant polytope, quasitoric manifold, small cover, Buchstaber number.

UDC: 515.145

Received: December 29, 2023
Revised: March 25, 2024
Accepted: April 28, 2024

DOI: 10.4213/tm4401


 English version:
Proceedings of the Steklov Institute of Mathematics, 2024, 326, 252–268


© Steklov Math. Inst. of RAS, 2025