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49 votes
3 answers
8k views

Thurston's 24 questions: All settled?

Thurston's 1982 article on three-dimensional manifolds1 ends with $24$ "open questions":       $\cdots$ Two naive questions from an outsider: (1) Have all $24$ now been resolved? (2)...
Joseph O'Rourke's user avatar
18 votes
2 answers
1k views

Hyperbolic Volume and Chern-Simons

In the paper ``Analytic Continuation Of Chern-Simons Theory'' (arXiv:1001.2933) Witten postulates that hyperbolic volume of 3-dimensional manifold coincides with the value of the Chern-Simons ...
d1-d5's user avatar
  • 183
18 votes
2 answers
2k views

How does hyperbolicity of space time affect our lives?

My main research has been in hyperbolic geometry and geometric group theory. I always thought that the only real "application" of my work was that the universe is a 3-manifold. But recently I found ...
Brian Rushton's user avatar
12 votes
3 answers
1k views

Is the cut locus of a generic point in a hyperbolic manifold a generic polyhedron?

Let $p\in M$ be a point in a closed riemannian manifold $M$. Recall that the cut locus of $p$ is the subset of $M$ consisting of all points that are connected to $p$ by at least 2 distance-minimizing ...
Bruno Martelli's user avatar
10 votes
1 answer
416 views

Diameter of hyperbolic 3-manifolds

Is there a good method to estimate the diameter of a closed hyperbolic 3-manifold? I am particularly interested in know the diameter of the Weeks manifold.
Vanderson Lima's user avatar
8 votes
1 answer
572 views

Mostow Rigidity Theorem and reconstruction from fundamental group

The Mostow Rigidity Theorem is phrased in terms of a relationship between isometries and isomorphisms of fundamental groups, which raises an obvious question. Given the fundamental group of a complete ...
Cameron Zwarich's user avatar
8 votes
1 answer
600 views

Questions on Thurston's metric on Teichmüller space

I'm reading the famous "Minimal stretch maps between hyperbolic surfaces" by William Thurston and I'm trying to understand the key theorem 8.1. I have many unclear points so I hope someone can help me ...
Redin's user avatar
  • 81
6 votes
1 answer
466 views

Hyperbolic manifolds with infinite cyclic fundamental group

It is a well known fact that there is a correspondence between complete hyperbolic $n$-manifolds up to isometry and discrete subgroups of isometries of the hyperbolic space $\mathbb{H}^n$ that act ...
Overflowian's user avatar
  • 2,533
6 votes
0 answers
389 views

A conjecture of Thurston and possibly Weeks too

What is the status of the following conjecture: "... [w]hen the shortest simple closed geodesics are repeatedly removed from any complete hyperbolic 3-manifold of finite volume, eventually one ...
Robert Haraway's user avatar
4 votes
1 answer
119 views

Does every hyperbolic, almost-transitive, triangulation of $\mathbb{R}^n$ have boundary homeomorphic with $\mathbb{S}^{n-1}$?

Question 1: Let $T$ be a triangulation of $\mathbb{R}^n$. Suppose that the 1-skeleton of $T$ endowed with the graph-metric (i.e. each 1-cell is given length 1) is Gromov-hyperbolic. Suppose moreover ...
Agelos's user avatar
  • 1,926
4 votes
1 answer
367 views

Compact open topology on the space of geodesics

I'm new in the field, so I'm sorry in advance if my question is too naive. Let's consider $S$ a surface of genus $g\ge 2$ with an hyperbolic metric $g$. Let's call $\mathcal{S}(S)$ the set of closed ...
gustav hertric's user avatar
3 votes
1 answer
569 views

Hyperbolic 3 manifold with trivial deformation of flat conformal structures

Does there exist closed hyperbolic three manifold which is locally rigid in the space of its all conformally flat structures? If so could someone provide examples?
Gorapada Bera's user avatar
3 votes
1 answer
239 views

Does the Weeks manifold have the smallest volume among all finite volume oriented hyperbolic 3-manifolds?

It is a result of Chinburg-Friedman-Jones-Reid that the arithmetic hyperbolic 3-manifold of smallest volume is the Weeks manifold. There is also a result of Milley that says that if $N$ is a closed ...
Colby's user avatar
  • 33
3 votes
1 answer
172 views

Why is $\mathcal{PML}_0(S)$ compact?

I'm starting to study geodesic laminations on hyperbolic surfaces and in particular I'm focusing my attention on $\mathcal{PML}_0(S)$, the space of projective classes of measured geodesic laminations ...
user avatar
3 votes
0 answers
267 views

What is the connection between $\mathrm{AdS}_2$ and the hyperbolic plane $\mathbb{H}^2$?

What is the connection between $\mathrm{AdS}_2$ and the hyperbolic plane $\mathbb{H}^2$? Some sources seem to imply that they are the same, i.e. having at least the same symmetry group $\mathrm{SL}(2,...
eriugena's user avatar
  • 679
3 votes
0 answers
198 views

Uniform continuity of length function on geodesic currents

I'm starting to study geodesic currents and I have a question concerning uniform continuity. Let's take $S$ a closed surface of genus $g$ and $GC(S)$ the space of geodesic currents on $S$ (as it is ...
user3419's user avatar
2 votes
1 answer
215 views

Lamination as limit of arcs

I am reading Bonahon's notes on closed curves, in particular the part about hyperbolic laminations. In his notes Bonahon illustrates some examples as why laminations should be "limit curves" on ...
user82786's user avatar
2 votes
1 answer
259 views

How to increase the injectivity radius function of a hyperbolic 3 manifold of finite volume?

Let $N$ be an oriented hyperbolic 3-manifold of finite volume and let $\Delta \subset N$ be a smooth connected compact subdomain such that the restriction of the injectivity radius function of $N$ to $...
Álvaro Krüger Ramos's user avatar
2 votes
2 answers
322 views

Why simple closed curves are dense in $\mathcal{PML}_0(S)$?

I have another question about laminations on surfaces. As usual let $\mathcal{S}$ be the set of homotopy classes of simple closed curves in $S$ and $\mathcal{PML}_0(S)$ be the set of projective ...
user avatar
2 votes
0 answers
177 views

Structure of hyperbolic manifolds of finite volume

Let $X$ be a hyperbolic manifold of finite volume. I want to prove that $X$ has ends of the form $N\times \mathbb{R}$ where $N$ has a finite covering by a nilmanifold and $\pi_1N\to \pi_1 X$ is ...
Radeha Longa's user avatar
1 vote
2 answers
925 views

Length of shortest geodesic and Cheeger's isoperimetric constant for a special genus 2 surface

Let us take two copies of $ Y $-pieces [ or pair of pants ] with each boundary geodesic of length $ l $, and glue them together without any twisting to obtain a genus 2 closed orientable hyperbolic ...
Analysis Now's user avatar
  • 1,471