Systoles of hyperbolic 4-manifolds

Systoles of hyperbolic surfaces with big cyclic symmetry

We obtain the exact values of the systoles of these hyperbolic surfaces of genus $g$ with cyclic symmetries of the maximum order and the next maximum order. Precisely: for genus $g$ hyperbolic surface with order $4g+2$ cyclic symmetry, the systole is $2\mathrm{arccosh} (1+\cos \fracπ{2g+1}+\cos \frac{2π}{2g+1})$ when $g\ge 7$, and for genus $g$ hyperbolic surface with order $4g$ cyclic symmetry, the systole is $2\mathrm{arccosh} (1+2\cos \fracπ{2g})$ when $g\ge4$.

Number of Systoles of Once-Punctured Torus and Four-Punctured Sphere

We compute the number of systoles, the shortest simple closed geodesics and 2-systoles, the second shortest simple closed geodesics on hyperbolic surfaces homeomorphic to once-punctured torus and four-punctured sphere.

On the systole growth in congruence quaternionic hyperbolic manifolds

We provide an explicit lower bound for the sytole in principal congruence covers of compact quaternionic hyperbolic manifolds. We also prove the optimality of this lower bound.

Systoles and diameters of hyperbolic surfaces

In this article we explore the relationship between the systole and the diameter of closed hyperbolic orientable surfaces. We show that they satisfy a certain inequality, which can be used to deduce that their ratio has a (genus dependent) upper bound.

Systoles and kissing numbers of finite area hyperbolic surfaces

We study the number and the length of systoles on complete finite area orientable hyperbolic surfaces. In particular, we prove upper bounds on the number of systoles that a surface can have (the so-called kissing number for hyperbolic surfaces). Our main result is a bound which only depends on the topology of the surface and which grows subquadratically in the genus.

On systoles and ortho spectrum rigidity

We consider the ortho spectrum of hyperbolic surfaces with totally geodesic boundary. We show that in general the ortho spectrum does not determine the systolic length but that there are only finitely many possibilities. As a corollary we show that, up to isometry, there are only finitely many hyperbolic structures on a surface that share a given ortho spectrum.

Graphs of Systoles on hyperbolic surfaces

Given a hyperbolic surface, the set of all closed geodesics whose length is minimal form a graph on the surface, in fact a so-called fat graph, which we call the systolic graph. We study which fat graphs are systolic graphs for some surface (we call these admissible). There is a natural necessary condition on such graphs, which we call combinatorial admissibility. Our first main result is that this condition is also sufficient. It follows that a sub-graph of an admissible graph is admissible. Our second major result is that there are infinitely many minimal non-admissible fat graphs (in contra…

The simple separating systole for hyperbolic surfaces of large genus

In this note we show that the expected value of the separating systole of a random surface of genus $g$ with respect to Weil-Petersson volume behaves like $2\log g $ as the genus goes to infinity. This is in strong contrast to the behavior of the expected value of the systole which, by results of Mirzakhani and Petri, is independent of genus.

Systole et rayon maximal des variétés hyperboliques non compactes

We bound two global invariants of cusped hyperbolic manifolds: the length of the shortest closed geodesic (the systole), and the radius of the biggest embedded ball (the inradius). We give an upper bound for the systole, expressed in terms of the dimension and simplicial volume. We find a positive lower bound on the inradius independent of the dimension. These bounds are sharp in dimension 3, realized by the Gieseking manifold. It provides a new characterization of this manifold.

双曲流形的收缩极小测地线密度

Density of systoles of hyperbolic manifolds

本文证明了闭双曲流形收缩极小测地线在正实数集中稠密，并揭示了其与Salem数及Salem猜想在算术双曲流形中的等价关系。

Hyperbolic punctured spheres without arithmetic systole maximizers

We find bounds for the length of the systole -- the shortest essential, non-peripheral closed curve -- for arithmetic punctured spheres with $n$ cusps, for $n=4$ through $n=12$, some of which were previously known due to Schmutz. This is shown using a correspondence between such surfaces and planar triangulations. We show that for $n=7,10,11$, arithmetic surfaces do not achieve the maximal systole length.

Systole growth for finite area hyperbolic surfaces

We are interested in the maximum value achieved by the systole function over all complete finite area hyperbolic surfaces of a given signature $(g,n)$. This maximum is shown to be strictly increasing in terms of the number of cusps for small values of $n$. We also show that this function is greater than a function that grows logarithmically in function of the ratio $g/n$.

关于算术流形的系数、 kissing 数和体积

On Systole, Kissing Number and Volume of Arithmetic Manifolds

本文通过超几何流形中系数和kissing数增长问题的解答，探讨算术群与算术流形的性质，总结二维结果及高维和其他局部对称空间的现状，并提出开放问题。

Systole Length in Hyperbolic $n$-Manifolds

We show that the length $R$ of a systole of a closed hyperbolic $n$-manifold $(n \geq 3)$ admitting a triangulation by $t$ $n$-simplices can be bounded below by a function of $n$ and $t$, namely \[ R \geq \frac{1}{2^{(nt)^{O(n^4t)} }} .\] We do this by finding a relation between the number of $n$-simplices and the diameter of the manifold and by giving explicit bounds for a well known relation between the length of the core curve of a Margulis tube and its radius. We prove the same result for finite volume manifolds, with a similar but slightly more involved proof.

双曲混合流形的最短闭测地线

Systoles of hyperbolic hybrids

本文通过混合构造方法，得到各维度中具有任意小最短闭测地线且非拟算术的闭双曲流形，证明其与已知构造不可公度。

随机双曲3-流形的 systole

The systole of random hyperbolic 3-manifolds

研究Petri和Raimbault引入的随机双曲3-流形模型中systole的极限期望值，并给出闭式公式及数值近似。

Bounds on Pachner moves and systoles of cusped 3-manifolds

Any two geometric ideal triangulations of a cusped complete hyperbolic $3$-manifold $M$ are related by a sequence of Pachner moves through topological triangulations. We give a bound on the length of this sequence in terms of the total number of tetrahedra and a lower bound on dihedral angles. This leads to a naive but effective algorithm to check if two hyperbolic knots are equivalent, given geometric ideal triangulations of their complements. Given a geometric ideal triangulation of $M$, we also give a lower bound on the systole length of $M$ in terms of the number of tetrahedra and a lower …

Systoles of Hyperbolic Manifolds

We show that for every $n\geq 2$ and any $ε>0$ there exists a compact hyperbolic $n$-manifold with a closed geodesic of length less than $ε$. When $ε$ is sufficiently small these manifolds are non-arithmetic, and they are obtained by a generalised inbreeding construction which was first suggested by Agol for $n=4$. We also show that for $n\geq 3$ the volumes of these manifolds grow at least as $1/ε^{n-2}$ when $ε\to 0$.

填充链环与本质收缩

Filling Links and Essential Systole

本文回答了Freedman和Krushkal的问题，在任意闭可定向3-流形中构造了具有大本质收缩的双曲填充链环，突破了先前对双曲链环的几何限制。

大亏格随机双曲曲面上的非简单收缩

Non-simple systoles on random hyperbolic surfaces for large genus

本文研究了Weil-Petersson测度下亏格为g的黎曼曲面模空间$\mathcal{M}_g$上随机双曲曲面的非简单收缩的渐近行为，证明当g→∞时其长度渐近于$\log g$。

具有大量systoles的双曲流形

Hyperbolic manifolds with a large number of systoles

本文对任意$n\geq 4$构造了紧双曲$n$-流形序列，证明了其systoles数量具有关于体积的下界，并改进了3维情形的界，将先前二维和三维的结果推广至更高维。

迹收缩长度与汇常数

Trace Systoles and Sink Constant

该研究定义了曲面基本群到SL(2,ℂ)表示的迹收缩长度，借助Markoff映射对应关系，显式算出三类曲面相对特征簇上的最优界，并得到双曲流形收缩不等式与非Fuchsian表示的相关推论。

On 2-systoles of hyperbolic 3-manifolds

We investigate the geometry of $π_1$-injective surfaces in closed hyperbolic 3-manifolds. First we prove that for any $e>0$, if the manifold $M$ has sufficiently large systole $\sys_1(M)$, the genus of any such surface in $M$ is bounded below by $\exp((1/2-e)\sys_1(M))$. Using this result we show, in particular, that for congruence covers $M_i\to M$ of a compact arithmetic hyperbolic 3-manifold we have: (a) the minimal genus of $π_1$-injective surfaces satisfies $\log \sysg(M_i) \gtrsim (1/3)\log\vol(M_i)$; (b) there exist such sequences with the ratio Heegard genus$(M_i)/\sysg(M_i) \gtrsim \v…

包含固定3-流形群的大系统距非均匀格

Non-Uniform Lattices of Large Systole Containing a Fixed 3-Manifold Group

本文构造了SL(8,R)中一列算术格，其系统距趋于无穷，但都包含同一个双曲3-流形群，证明这是高秩格独有的现象。

没有正旋转三角剖分的双曲流形

Hyperbolic manifolds without positive spun triangulations

研究由闭双曲三维流形和简单闭测地线组成的对，利用Choi结果给出无前述正旋转理想三角剖分的例子，如Vol3及相关测地线，为Vol3无此类三角剖分猜想提供证据。

Bounding volume by systoles of 3-manifolds

We prove a new systolic volume lower bound for non-orientable n-manifolds, involving the stable 1-systole and the codimension 1 systole with coefficients in Z_2. As an application, we prove that Lusternik-Schnirelmann category and systolic category agree for non-orientable closed manifolds of dimension 3, extending our earlier result in the orientable case. Finally, we prove the homotopy invariance of systolic category.

The injectivity radius of hyperbolic surfaces and some Morse functions over moduli spaces

This article is devoted to the variational study of two functions defined over some Teichmueller spaces of hyperbolic surfaces. One is the systole of geodesic loops based at some fixed point, and the other one is the systole of arcs.\par For each of them we determine all the critical points. It appears that the systole of arcs is a topological Morse function, whereas the systole of geodesic loops have some degenerate critical points. However, these degenerate critical points are in some sense the obvious one, and they do not interfere in the variational study of the function.\par At a nondegen…

Systoles of Arithmetic Hyperbolic Surfaces and 3-manifolds

Our main result is that for all sufficiently large $x_0>0$, the set of commensurability classes of arithmetic hyperbolic 2- or 3-orbifolds with fixed invariant trace field $k$ and systole bounded below by $x_0$ has density one within the set of all commensurability classes of arithmetic hyperbolic 2- or 3-orbifolds with invariant trace field $k$. The proof relies upon bounds for the absolute logarithmic Weil height of algebraic integers due to Silverman, Brindza and Hajdu, as well as precise estimates for the number of rational quaternion algebras not admitting embeddings of any quadratic fiel…

Systolic Surfaces of Arithmetic Hyperbolic 3-Manifolds

In this paper we examine the geometry of minimal surfaces of arithmetic hyperbolic 3-manifolds. In particular, we give bounds on the totally geodesic 2-systole, construct infinitely many incommensurable manifolds with the same initial geometric genus spectrum in which volume and 1-systole are controlled, and analyze the growth of the genera of minimal surfaces across commensurability classes. These results have applications to the study of how Heegard genus grows across commensurability classes.

紧致双曲曲面上的相交数、长度与收缩线

Intersection Number, Length, and Systole on Compact Hyperbolic Surfaces

本研究针对紧致双曲曲面的相互作用强度I(X)，分别推导了其在模空间$M_g$中曲面趋于无穷时依收缩线长度的渐近行为，以及亏格g趋于无穷时$M_g$上I(X)最小值的近似行为。

Asymptotic properties of the set of systoles of arithmetic Riemann surfaces

The purpose this article is to try to understand the mysterious coincidence between the asymptotic behavior of the volumes of the Moduli Space of closed hyperbolic surfaces of genus $g$ with respect to the Weil-Petersson metric and the asymptotic behavior of the number of arithmetic closed hyperbolic surfaces of genus $g$. If the set of arithmetic surfaces is well distributed then its image for any interesting function should be well distributed too. We investigate the distribution of the function systole. We give several results indicating that the systoles of arithmetic surfaces can not be c…

Currents, Systoles, and Compactifications of Character Varieties

We study the Weyl chamber length boundary both of the Hitchin and of the maximal character varieties and determine therein an open set of discontinuity for the action of the mapping class group. This result is obtained as consequence of a canonical decomposition of a geodesic current on a surface of finite type arising from a topological decomposition of the surface along special geodesics. We show that each component either is associated to a measured lamination or has positive systole. For a current with positive systole, we show that the intersection function on the set of closed curves is …

具有最大 $S^3$ 可扩展阿贝尔对称性的双曲曲面的最大 systole

Maximal systole of hyperbolic surface with largest $S^3$ extendable abelian symmetry

本文给出了具有最大 $S^3$ 可扩展阿贝尔对称性的双曲曲面的最大 systole 公式，结果为 $2\mathrm{arccosh} K$，其中 $K$ 由 $L=4\cos^2(\pi/(g-1))$ 确定。

Closed Geodesic Length Bounds of Hyperbolic Link Complements in Hyperbolic $3$-Manifolds

Let $M$ be a compact hyperbolic $3$-manifold with volume $V$. Let $L$ be a link such that $M\setminus L$ is hyperbolic. For any hyperbolic link $L$ in $M$, in this article, we establish an upper bound of the length of an $n^{th}$ shortest closed geodesic as a logarithmic function of $V$ in $M\setminus L$. Our works complement the work of Lakeland and Leininger \cite{Christopher} on the upper bound of systole length.

同余覆盖中k维收缩量的增长

Growth of k-dimensional systoles in congruence coverings

本文研究算术n-流形在同余覆盖下k维收缩量的增长，发现实秩r>1且k=r时增长函数在对数幂与覆盖次数幂之间振荡的新现象，并证明了小k与大k情形下的多对数界和常数幂界。

Dyck's surfaces, systoles, and capacities

We prove an optimal systolic inequality for nonpositively curved Dyck's surfaces. The extremal surface is flat with eight conical singularities, six of angle theta and two of angle 9pi - theta, for a suitable theta with cos(theta) in Q(sqrt{19}). Relying on some delicate capacity estimates, we also show that the extremal surface is not conformally equivalent to the hyperbolic surface with maximal systole, yielding a first example of systolic extremality with this behavior.

The maximal injectivity radius of hyperbolic surfaces with geodesic boundary

We give sharp upper bounds on the injectivity radii of complete hyperbolic surfaces of finite area with some geodesic boundary components. The given bounds are over all such surfaces with any fixed topology; in particular, boundary lengths are not fixed. This extends the first author's result to the with-boundary setting. In the second part of the paper we comment on another direction for extending this result, via the systole of loops function.

Hyperbolic polygons of minimal perimeter in punctured discs

We prove that, among the polygons in a punctured disc with fixed angles, the perimeter is minimized by the polygon with an inscribed horocycle centered at the puncture. We generalize this to a disc with a cone point and to an annulus with a geodesic boundary component and a complete end. Then we apply this result to describe the minimum of the spine systole on the moduli space of punctured surfaces.

闭合双曲面拼接的计数与熵

Counting and entropy for hyperbolic surface amalgams

研究闭合双曲面拼接中闭合测地线数量的增长，证明拓扑熵与体积熵相等，但其行为受几何数据影响，特别是通过系统孔径长度和拼接曲线长度的上下界影响，熵在无系统孔径下界时可指数增长。

Graphs of Large Girth and Surfaces of Large Systole

The systole of a hyperbolic surface is bounded by a logarithmic function of its genus. This bound is sharp, in that there exist sequences of surfaces with genera tending to infinity that attain logarithmically large systoles. These are constructed by taking congruence covers of arithmetic surfaces. In this article we provide a new construction for a sequence of surfaces with systoles that grow logarithmically in their genera. We do this by combining a construction for graphs of large girth and a count of the number of $\mathrm{SL}_2(\mathbb{Z})$ matrices with positive entries and bounded trace…

Geodesics, volumes and Lehmer's conjecture

In this report I discuss the relations between systoles and volumes of hyperbolic manifolds and a conjecture of Lehmer about the Mahler measure of non-cyclotomic polynomials.

Systole函数与Weil-Petersson几何

Systole functions and Weil-Petersson geometry

本文研究Teichmüller空间中沿systolic曲线的测地线长度函数梯度的L^p范数，证明其与systole的幂次一致可比，并由此得出最小Weil-Petersson全纯截面曲率有统一负上界，否定了Mirzakhani的问题。

Volume and homology growth of aspherical manifolds

We provide upper bounds on the size of the homology of a closed aspherical Riemannian manifold that only depend on the systole and the volume of balls. Further, we show that linear growth of mod p Betti numbers or exponential growth of torsion homology imply that a closed aspherical manifold is "large".

Universal systole bounds for arithmetic locally symmetric spaces

The systole of a closed Riemannian manifold is the minimal length of a non-contractible closed loop. We give a uniform lower bound for the systole for large classes of simple arithmetic locally symmetric orbifolds. We establish new bounds for the translation length of a semisimple element x in SL_n(R) in terms of its associated Mahler measure. We use these geometric methods to prove the existence of extensions of number fields in which fixed sets of primes have certain prescribed splitting behavior.

Uniform bounds on harmonic Beltrami differentials and Weil-Petersson curvatures

In this article we show that for every finite area hyperbolic surface $X$ of type $(g,n)$ and any harmonic Beltrami differential $μ$ on $X$, then the magnitude of $μ$ at any point of small injectivity radius is uniform bounded from above by the ratio of the Weil-Petersson norm of $μ$ over the square root of the systole of $X$ up to a uniform positive constant multiplication. We apply the uniform bound above to show that the Weil-Petersson Ricci curvature, restricted at any hyperbolic surface of short systole in the moduli space, is uniformly bounded from below by the negative reciprocal of the…

具有有界秩和任意大 systole 的曲面乘积的有限覆盖

Finite covers of a product of surfaces with bounded rank and arbitrarily large systole

本文构造了亏格二双曲曲面乘积的有限覆盖，其基本群生成元数有界而内射半径趋于无穷，为高秩对称空间上的 Avramidi-Delzant 猜想提供了反例。

Kissing numbers for surfaces

The so-called {\it kissing number} for hyperbolic surfaces is the maximum number of homotopically distinct systoles a surface of given genus $g$ can have. These numbers, first studied (and named) by Schmutz Schaller by analogy with lattice sphere packings, are known to grow, as a function of genus, at least like $g^{\sfrac{4}{3}-ε}$ for any $ε>0$. The first goal of this article is to give upper bounds on these numbers; in particular the growth is shown to be sub-quadratic. In the second part, a construction of (non hyperbolic) surfaces with roughly $g^{\sfrac{3}{2}}$ systoles is given.

小 Systle 集与 Coxeter 群

Small Systle Sets and Coxeter Groups

本文基于 Coxeter 群理论与初等数论，改进 Schmutz 的方法，构造了具有任意大亏格且其 systole 集合基数低至 o(g/ ln g) 仍能填充曲面的闭双曲曲面。

Four-manifold systoles and surjectivity of period map

P. Buser and P. Sarnak showed in 1994 that the maximum, over the moduli space of Riemann surfaces of genus s, of the least conformal length of a nonseparating loop, is logarithmic in s. We present an application of (polynomially) dense Euclidean packings, to estimates for an analogous 2-dimensional conformal systolic invariant of a 4-manifold X with indefinite intersection form. The estimate turns out to be polynomial, rather than logarithmic, in χ(X), if the conjectured surjectivity of the period map is correct. Such surjectivity is targeted by the current work in gauge theory. The surjectivi…

Paysage Systolique Des Surfaces Hyperboliques Compactes De Caracteristique -1

We determine optimal inequalities for the systole of all hyperbolic compact surfaces of caracteristic -1. First, we study the geometry and topology of these surfaces. Then, we describe the action of modular groups on Teichmüller spaces. Finaly, we give cell decompositions of fundamental domains such as the set of systoles is constant over a cell. Other optimal inequalities for other metric invariants are also given.

Kissing numbers of closed hyperbolic manifolds

We prove an upper bound for the number of shortest closed geodesics in a closed hyperbolic manifold of any dimension in terms of its volume and systole, generalizing a theorem of Parlier for surfaces. We also obtain bounds on the number of primitive closed geodesics with length in a given interval that are uniform for all closed hyperbolic manifolds with bounded geometry. The proofs rely on the Selberg trace formula.

On manifolds satisfying stable systolic inequalities

We show that for closed orientable manifolds the $k$-dimensional stable systole admits a metric-independent volume bound if and only if there are cohomology classes of degree $k$ that generate cohomology in top-degree. Moreover, it turns out that in the nonorientable case such a bound does not exist for stable systoles of dimension at least two. Additionally, we prove that the stable systolic constant depends only on the image of the fundamental class in a suitable Eilenberg-Mac Lane space. Consequently, the stable $k$-systolic constant is completely determined by the multilinear intersection …

熵与体积 via 海格劳德图

Entropy versus volume via Heegaard diagrams

该研究通过海格劳德弗洛尔同调和双曲几何，建立了双曲3流形的熵与体积之间的不等式关系，改进了Kojima的结果。

Löbell多面体的几何与算术性质

Geometric and arithmetic properties of Löbell polyhedra

本文研究Löbell多面体的几何与算术性质，证明其短闭测地线可任意小且在可公度意义下仍为无限族，并精确刻画其中的拟算术成员。