JP Journal of Geometry and Topology

The JP Journal of Geometry and Topology publishes articles in all branches of geometry and topology, with applications to physics. It covers areas such as differential geometry, algebraic topology, and geometric aspects of mathematical physics. Survey articles are also welcome.

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ON FINITENESS OF THE GEODESICS JOINING A PAIR OF POINTS IN CURVE COMPLEX

Authors

  • Kanako Oie

Keywords:

curve complex, geodesics, subsurface projection.

DOI:

https://doi.org/10.17654/0972415X24005

Abstract

Let $S$ be a genus $g$ orientable surface with $c$ boundary components and $p$ punctures. Then $\mathcal{C}^0(S)$ denotes the 0 -skeleton of the curve complex of $S$. This paper presents the following results:
(1) If " $g=1, c+p \geq 3$ " or " $g \geq 2, c+p \geq 1$ ", then, there exist $a_0, a_2 \in \mathcal{C}^0(S)$ such that $d_S\left(a_0, a_2\right)=2$ and the number of the geodesics joining $a_0$ and $a_2$ is exactly 2 .
(2) If " $g=2, c+p \geq 1$ " or " $g \geq 3$ ", then, there exist $a_0, a_2 \in$ $\mathcal{C}^0(S)$ such that $d_S\left(a_0, a_2\right)=2$ and the number of the geodesics joining $a_0$ and $a_2$ is exactly 3 .

Received: March 13, 2024
Accepted: April 12, 2024

References

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H. Masur and Y. Minsky, Geometry of the complex of curves, I. Hyperbolicity, Invent. Math. 138 (1999), 103-149.

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Published

2024-05-16

Issue

Section

Articles

How to Cite

ON FINITENESS OF THE GEODESICS JOINING A PAIR OF POINTS IN CURVE COMPLEX. (2024). JP Journal of Geometry and Topology, 30(1), 69-82. https://doi.org/10.17654/0972415X24005