Generating the liftable mapping class groups of regular cyclic covers

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Dey, Soumya, Dhanwani, Neeraj K., Patil, Harsh, Rajeevsarathy, Kashyap
Natura: Preprint
Pubblicazione: 2021
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866909596093775872
author Dey, Soumya
Dhanwani, Neeraj K.
Patil, Harsh
Rajeevsarathy, Kashyap
author_facet Dey, Soumya
Dhanwani, Neeraj K.
Patil, Harsh
Rajeevsarathy, Kashyap
contents Let $\mathrm{Mod}(S_g)$ be the mapping class group of the closed orientable surface of genus $g \geq 1$, and let $\mathrm{LMod}_{p}(X)$ be the liftable mapping class group associated with a finite-sheeted branched cover $p:S \to X$, where $X$ is a hyperbolic surface. For $k \geq 2$, let $p_k: S_{k(g-1)+1} \to S_g$ be the standard $k$-sheeted regular cyclic cover. In this paper, we show that $\{\mathrm{LMod}_{p_k}(S_g)\}_{k \geq 2}$ forms an infinite family of self-normalizing subgroups in $\mathrm{Mod}(S_g)$, which are also maximal when $k$ is prime. Furthermore, we derive explicit finite generating sets for $\mathrm{LMod}_{p_k}(S_g)$ for $g \geq 3$ and $k \geq 2$, and $\mathrm{LMod}_{p_2}(S_2)$. For $g \geq 2$, as an application of our main result, we also derive a generating set for $\mathrm{LMod}_{p_2}(S_g) \cap C_{\mathrm{Mod}(S_g)}(ι)$, where $C_{\mathrm{Mod}(S_g)}(ι)$ is the centralizer of the hyperelliptic involution $ι\in \mathrm{Mod}(S_g)$. Let $\mathcal{L}$ be the infinite ladder surface, and let $q_g : \mathcal{L} \to S_g$ be the standard infinite-sheeted cover induced by $\langle h^{g-1} \rangle$ where $h$ is the standard handle shift on $\mathcal{L}$. As a final application, we derive a finite generating set for $\mathrm{LMod}_{q_g}(S_g)$ for $g \geq 3$.
format Preprint
id arxiv_https___arxiv_org_abs_2111_01626
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Generating the liftable mapping class groups of regular cyclic covers
Dey, Soumya
Dhanwani, Neeraj K.
Patil, Harsh
Rajeevsarathy, Kashyap
Geometric Topology
Group Theory
57M60 (Primary) 57M50, 57M99 (Secondary)
Let $\mathrm{Mod}(S_g)$ be the mapping class group of the closed orientable surface of genus $g \geq 1$, and let $\mathrm{LMod}_{p}(X)$ be the liftable mapping class group associated with a finite-sheeted branched cover $p:S \to X$, where $X$ is a hyperbolic surface. For $k \geq 2$, let $p_k: S_{k(g-1)+1} \to S_g$ be the standard $k$-sheeted regular cyclic cover. In this paper, we show that $\{\mathrm{LMod}_{p_k}(S_g)\}_{k \geq 2}$ forms an infinite family of self-normalizing subgroups in $\mathrm{Mod}(S_g)$, which are also maximal when $k$ is prime. Furthermore, we derive explicit finite generating sets for $\mathrm{LMod}_{p_k}(S_g)$ for $g \geq 3$ and $k \geq 2$, and $\mathrm{LMod}_{p_2}(S_2)$. For $g \geq 2$, as an application of our main result, we also derive a generating set for $\mathrm{LMod}_{p_2}(S_g) \cap C_{\mathrm{Mod}(S_g)}(ι)$, where $C_{\mathrm{Mod}(S_g)}(ι)$ is the centralizer of the hyperelliptic involution $ι\in \mathrm{Mod}(S_g)$. Let $\mathcal{L}$ be the infinite ladder surface, and let $q_g : \mathcal{L} \to S_g$ be the standard infinite-sheeted cover induced by $\langle h^{g-1} \rangle$ where $h$ is the standard handle shift on $\mathcal{L}$. As a final application, we derive a finite generating set for $\mathrm{LMod}_{q_g}(S_g)$ for $g \geq 3$.
title Generating the liftable mapping class groups of regular cyclic covers
topic Geometric Topology
Group Theory
57M60 (Primary) 57M50, 57M99 (Secondary)
url https://arxiv.org/abs/2111.01626