Charalampos Stylianakis

activity

20242026

collaborators

5 papers

math.GR2026

Forbidden relations in universal virtual braid groups

Oscar Ocampo, Charalampos Stylianakis

We study natural automorphisms of the universal virtual braid group $U V_{n} (k)$ . These automorphisms induce commuting involutions in the outer automorphism group and generate a subgr…

math.GT2026

Finiteness properties of the Torelli group of surfaces with 2 boundary components

Charalampos Stylianakis

In this paper we prove that the Torelli group of a surface of genus at least 3 with 2 boundary components is finitely generated. As a consequence, we answer Putman's question on th…

math.GR2025

Powers of half-twists and congruence subgroups of braid groups

Paolo Bellingeri, Celeste Damiani, Oscar Ocampo +1

In this work, we study the relationship between congruence subgroups $B_{n} [m]$ and $N_{n} (I ¨ _{1}^{m})$ the normal closure of $I ¨ _{1}^{m}$ , where $I ¨ _{1}$ is the classical generator of…

math.GR2025

Congruence subgroups of braid groups and crystallographic quotients. Part II

Paolo Bellingeri, Celeste Damiani, Oscar Ocampo +1

Following previous work on congruence subgroups and crystallographic braid groups, we study the lower central series of congruence braid groups related to the braid group $B_{3}$ , sh…

math.GR2024

Congruence subgroups of braid groups and crystallographic quotients. Part I

Paolo Bellingeri, Celeste Damiani, Oscar Ocampo +1

This paper is the first of a two part series devoted to describing relations between congruence and crystallographic braid groups. We recall and introduce some elements belonging t…