Liftable homeomorphisms of rank two finite abelian branched covers

Atalan F., Medetogullari E., Ozan Y.

ARCHIV DER MATHEMATIK, cilt.116, sa.1, ss.37-48, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 116 Sayı: 1
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1007/s00013-020-01501-z
  • Dergi Adı: ARCHIV DER MATHEMATIK
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, MathSciNet, zbMATH, DIALNET
  • Sayfa Sayıları: ss.37-48
  • Anahtar Kelimeler: Branched covers, Mapping class group, Automorphisms of groups
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

We investigate branched regular finite abelian A-covers of the 2-sphere, where every homeomorphism of the base (preserving the branch locus) lifts to a homeomorphism of the covering surface. In this study, we prove that if A is a finite abelian p-group of rank k and Sigma -> S-2 is a regular A-covering branched over n points such that every homeomorphism f:S-2 -> S-2 lifts to Sigma, then n = k + 1. We will also give a partial classification of such covers for rank two finite p-groups. In particular, we prove that for a regular branched A-covering pi : Sigma -> S-2, where A = ZprxZpt, 1 <= r <= t , all homeomorphisms f:S-2 -> S-2 lift to those of Sigma if and only if t = r or t = r + 1 and p = 3.