On the universal and generalized orbifold Euler characteristics

S.M. Gusein-Zade, I. Luengo, A. Melle-Hernández, and A. Viruel

Journal of Singularities
volume 30 (2026), 207-215

Received: 18 October 2025. In revised form: 7 December 2025

DOI: 10.5427/jsing.2026.30h


Abstract:

We discuss the universal orbifold Euler characteristic and generalized orbifold Euler characteristics corresponding to finitely generated groups A (the {A-Euler characteristics}). We show that the collection of all A-Euler characteristics for A of the form A'x Z with finite A' determines the universal orbifold Euler characteristic.


2020 Mathematical Subject Classification:

57S17, 55M35


Key words and phrases:

orbifolds, finite group actions, generalized orbifold Euler characteristics


Author(s) information:

S.M. Gusein-Zade
Lomonosov Moscow State University
Faculty of Mechanics and Mathematics and
Moscow Center for Fundamental and Applied Mathematics
GSP-1
Moscow, 119991, Russia
and
National Research University
"Higher School of Economics"
Usacheva street 6
Moscow, 119048, Russia
email: sabir@mccme.ru

I. Luengo
Department of Algebra, Geometry and Topology
Complutense University of Madrid
Madrid, 28040 Spain
email: iluengo@ucm.es

A. Melle-Hernández, Instituto de Matemática Interdisciplinar (IMI)
Department of Algebra, Geometry and Topology
Complutense University of Madrid
Madrid, 28040 Spain
email: amelle@ucm.es

A. Viruel
Departamento de Álgebra, Geometría y Topología
Universidad de Málaga
Campus de Teatinos
29071-Málaga, Spain
email: viruel@uma.es