Abstract
The simplicial wedge construction on simplicial complexes and simple polytopes has been used by a variety of authors to study toric and related spaces, including non-singular toric varieties, toric manifolds, intersections of quadrics and more generally, polyhedral products. In this paper we extend the analysis to include toric orbifolds. Our main results yield infinite families of toric orbifolds, derived from a given one, whose integral cohomology is free of torsion and is concentrated in even degrees, a property which might be termed integrally equivariantly formal. In all cases, it is possible to give a description of the cohomology ring and to relate it to the cohomology of the original orbifold.
Funding source: Simons Foundation
Award Identifier / Grant number: 210386
Award Identifier / Grant number: 426160
Funding source: National Research Foundation of Korea
Award Identifier / Grant number: NRF-2018R1D1A1B07048480
Funding statement: This work was supported in part by grants 210386 and 426160 from Simons Foundation. The third author has been supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2018R1D1A1B07048480). He also has been supported by the POSCO Science Fellowship of POSCO TJ Park Foundation.
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