Saved in:
Bibliographic Details
Main Authors: Matsuda, Ryo, Oie, Kanako, Shiga, Hiroshige
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2505.01801
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909666463711232
author Matsuda, Ryo
Oie, Kanako
Shiga, Hiroshige
author_facet Matsuda, Ryo
Oie, Kanako
Shiga, Hiroshige
contents Let $S$ be an oriented surface of type $(g, n)$. We are interested in geodesics in the curve complex $\mathcal C(S)$ of $S$. In general, two $0$-simplexes in $\mathcal C(S)$ have infinitely many geodesics connecting the two simplexes while another geodesics called tight geodesics are always finitely many. On the other hand, we may find two $0$-simplexes in $\mathcal C(S)$ so that they have only finitely many geodesics between them. In this paper, we consider the spectrum of the number of geodesics with length $d (\geq 2)$ in $\mathcal C(S)$ and tight geodesics, which is denoted by $\mathfrak{Sp}_d(S)$ and $\mathfrak{Sp}_d^T(S)$, respectively. In our main theorem, it is shown that $\mathfrak{Sp}_d(S) \subset \mathfrak{Sp}_d^T(S)$ in general, but $\mathfrak{Sp}_2(S)= \mathfrak{Sp}_2^T(S)$. Moreover, we show that $\mathfrak{Sp}_2(S)$ and $\mathfrak{Sp}_2^T(g, n)$ are completely determined in terms of $(g, n)$.
format Preprint
id arxiv_https___arxiv_org_abs_2505_01801
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle On the spectrum of the number of geodesics and tight geodesics in the curve complex
Matsuda, Ryo
Oie, Kanako
Shiga, Hiroshige
Geometric Topology
Primary 57K20, Secondary 57K99
Let $S$ be an oriented surface of type $(g, n)$. We are interested in geodesics in the curve complex $\mathcal C(S)$ of $S$. In general, two $0$-simplexes in $\mathcal C(S)$ have infinitely many geodesics connecting the two simplexes while another geodesics called tight geodesics are always finitely many. On the other hand, we may find two $0$-simplexes in $\mathcal C(S)$ so that they have only finitely many geodesics between them. In this paper, we consider the spectrum of the number of geodesics with length $d (\geq 2)$ in $\mathcal C(S)$ and tight geodesics, which is denoted by $\mathfrak{Sp}_d(S)$ and $\mathfrak{Sp}_d^T(S)$, respectively. In our main theorem, it is shown that $\mathfrak{Sp}_d(S) \subset \mathfrak{Sp}_d^T(S)$ in general, but $\mathfrak{Sp}_2(S)= \mathfrak{Sp}_2^T(S)$. Moreover, we show that $\mathfrak{Sp}_2(S)$ and $\mathfrak{Sp}_2^T(g, n)$ are completely determined in terms of $(g, n)$.
title On the spectrum of the number of geodesics and tight geodesics in the curve complex
topic Geometric Topology
Primary 57K20, Secondary 57K99
url https://arxiv.org/abs/2505.01801