Pub Date : 2025-09-01Epub Date: 2025-05-09DOI: 10.1016/j.difgeo.2025.102252
Pengpeng Cheng, Tongzhu Li
Let be a closed immersed minimal hypersurface with constant squared length of the second fundamental form S in a 5-dimensional sphere . In this paper, we prove that if the 3-mean curvature and the number g of the distinct principal curvatures are constant, then is an isoparametric hypersurface, and the value of S can only be . This result supports Chern Conjecture.
{"title":"Rigidity of closed minimal hypersurfaces in S5","authors":"Pengpeng Cheng, Tongzhu Li","doi":"10.1016/j.difgeo.2025.102252","DOIUrl":"10.1016/j.difgeo.2025.102252","url":null,"abstract":"<div><div>Let <span><math><msup><mrow><mi>M</mi></mrow><mrow><mn>4</mn></mrow></msup><mo>→</mo><msup><mrow><mi>S</mi></mrow><mrow><mn>5</mn></mrow></msup></math></span> be a closed immersed minimal hypersurface with constant squared length of the second fundamental form <em>S</em> in a 5-dimensional sphere <span><math><msup><mrow><mi>S</mi></mrow><mrow><mn>5</mn></mrow></msup></math></span>. In this paper, we prove that if the 3-mean curvature <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span> and the number <em>g</em> of the distinct principal curvatures are constant, then <span><math><msup><mrow><mi>M</mi></mrow><mrow><mn>4</mn></mrow></msup></math></span> is an isoparametric hypersurface, and the value of <em>S</em> can only be <span><math><mn>0</mn><mo>,</mo><mn>4</mn><mo>,</mo><mn>12</mn></math></span>. This result supports Chern Conjecture.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"100 ","pages":"Article 102252"},"PeriodicalIF":0.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-01Epub Date: 2025-07-16DOI: 10.1016/j.difgeo.2025.102272
Antonio Michele Miti , Leonid Ryvkin
The purpose of this paper is to present a fully algebraic formalism for the construction and reduction of -algebras of observables inspired by multisymplectic geometry, using Gerstenhaber algebras, BV-modules, and the constraint triple formalism. In the “geometric case”, we reconstruct and conceptually explain the recent results of [7].
{"title":"Multisymplectic observable reduction using constraint triples","authors":"Antonio Michele Miti , Leonid Ryvkin","doi":"10.1016/j.difgeo.2025.102272","DOIUrl":"10.1016/j.difgeo.2025.102272","url":null,"abstract":"<div><div>The purpose of this paper is to present a fully algebraic formalism for the construction and reduction of <span><math><msub><mrow><mi>L</mi></mrow><mrow><mo>∞</mo></mrow></msub></math></span>-algebras of observables inspired by multisymplectic geometry, using Gerstenhaber algebras, BV-modules, and the constraint triple formalism. In the “geometric case”, we reconstruct and conceptually explain the recent results of <span><span>[7]</span></span>.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"100 ","pages":"Article 102272"},"PeriodicalIF":0.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144634476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-01Epub Date: 2025-07-02DOI: 10.1016/j.difgeo.2025.102268
Chang-Jian Zhao
In the paper, our main aim is to generalize the dual mixed harmonic quermassintegrals to Orlicz space. Under the framework of Orlicz dual Brunn-Minkowski theory, we introduce a new affine geometric quantity by calculating Orlicz first order variation of the dual mixed harmonic quermassintegrals, and call it the Orlicz dual mixed harmonic quermassintegrals. The fundamental notions and conclusions of the dual mixed harmonic quermassintegrals and the Minkowski and Brunn-Minkowski inequalities for the dual harmonic quermassintegrals are extended to an Orlicz setting, and the related concepts and inequalities of Orlicz dual mixed volumes are also included in our conclusions.
{"title":"Orlicz harmonic version of dual mixed volumes","authors":"Chang-Jian Zhao","doi":"10.1016/j.difgeo.2025.102268","DOIUrl":"10.1016/j.difgeo.2025.102268","url":null,"abstract":"<div><div>In the paper, our main aim is to generalize the dual mixed harmonic quermassintegrals to Orlicz space. Under the framework of Orlicz dual Brunn-Minkowski theory, we introduce a new affine geometric quantity by calculating Orlicz first order variation of the dual mixed harmonic quermassintegrals, and call it the Orlicz dual mixed harmonic quermassintegrals. The fundamental notions and conclusions of the dual mixed harmonic quermassintegrals and the Minkowski and Brunn-Minkowski inequalities for the dual harmonic quermassintegrals are extended to an Orlicz setting, and the related concepts and inequalities of Orlicz dual mixed volumes are also included in our conclusions.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"100 ","pages":"Article 102268"},"PeriodicalIF":0.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144534227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-06-01Epub Date: 2025-03-09DOI: 10.1016/j.difgeo.2025.102240
Elias Knack, Henrik Naujoks
Let and be two pseudo-Riemannian manifolds. We study field theoretic properties of higher-power harmonic maps (also called r-harmonic maps) , which are a natural generalization of standard harmonic maps first introduced by C. Wood. In particular, we discuss the coupled system of higher-power harmonic maps and the Einstein-Hilbert action and prove a sufficient condition for a map to be r-harmonic, which is highly motivated by classical field equations like the harmonic map equation or the Yang-Mills equation. Furthermore, we derive an instanton theory for r-harmonic maps on 2r-dimensional base manifolds and investigate conformal properties of general higher-power harmonic maps. Finally, since the theory of higher-power harmonic maps bears striking similarities with Yang-Mills theory, we provide a comprehensive comparison between the two theories which explains in more detail surprisingly many analogies.
{"title":"Higher-power harmonic maps, instantons and Yang-Mills theory","authors":"Elias Knack, Henrik Naujoks","doi":"10.1016/j.difgeo.2025.102240","DOIUrl":"10.1016/j.difgeo.2025.102240","url":null,"abstract":"<div><div>Let <span><math><mo>(</mo><mi>M</mi><mo>,</mo><mi>g</mi><mo>)</mo></math></span> and <span><math><mo>(</mo><mi>N</mi><mo>,</mo><mi>h</mi><mo>)</mo></math></span> be two pseudo-Riemannian manifolds. We study field theoretic properties of higher-power harmonic maps (also called <em>r</em>-harmonic maps) <span><math><mi>φ</mi><mo>:</mo><mi>M</mi><mo>→</mo><mi>N</mi></math></span>, which are a natural generalization of standard harmonic maps first introduced by C. Wood. In particular, we discuss the coupled system of higher-power harmonic maps and the Einstein-Hilbert action and prove a sufficient condition for a map to be <em>r</em>-harmonic, which is highly motivated by classical field equations like the harmonic map equation or the Yang-Mills equation. Furthermore, we derive an instanton theory for <em>r</em>-harmonic maps on 2<em>r</em>-dimensional base manifolds and investigate conformal properties of general higher-power harmonic maps. Finally, since the theory of higher-power harmonic maps bears striking similarities with Yang-Mills theory, we provide a comprehensive comparison between the two theories which explains in more detail surprisingly many analogies.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"99 ","pages":"Article 102240"},"PeriodicalIF":0.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-06-01Epub Date: 2025-03-27DOI: 10.1016/j.difgeo.2025.102245
Tomasz Goliński , Fernand Pelletier
We consider regulated curves in a Banach bundle whose projection on the basis is continuous with regulated derivative. We build a Banach manifold structure on the set of such curves. This result was previously obtained for the case of strong Riemannian Banach manifold and absolutely continuous curves in [16]. The essential argument used was the existence of a “local addition” on such a manifold. Our proof is true for any Banach manifold. In the second part of the paper the problems of controllability will be discussed.
{"title":"Regulated curves on a Banach manifold and singularities of endpoint map. I. Banach manifold structure","authors":"Tomasz Goliński , Fernand Pelletier","doi":"10.1016/j.difgeo.2025.102245","DOIUrl":"10.1016/j.difgeo.2025.102245","url":null,"abstract":"<div><div>We consider regulated curves in a Banach bundle whose projection on the basis is continuous with regulated derivative. We build a Banach manifold structure on the set of such curves. This result was previously obtained for the case of strong Riemannian Banach manifold and absolutely continuous curves in <span><span>[16]</span></span>. The essential argument used was the existence of a “local addition” on such a manifold. Our proof is true for any Banach manifold. In the second part of the paper the problems of controllability will be discussed.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"99 ","pages":"Article 102245"},"PeriodicalIF":0.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-06-01Epub Date: 2025-04-04DOI: 10.1016/j.difgeo.2025.102246
David Li-Bland, Eckhard Meinrenken
It is a remarkable fact that the integrability of a Poisson manifold to a symplectic groupoid depends only on the integrability of its cotangent Lie algebroid A: The source-simply connected Lie groupoid integrating A automatically acquires a multiplicative symplectic 2-form. More generally, a similar result holds for the integration of Lie bialgebroids to Poisson groupoids, as well as in the ‘quasi’ settings of Dirac structures and quasi-Lie bialgebroids. In this article, we will place these results into a general context of Manin pairs , thereby obtaining a simple geometric approach to these integration results. We also clarify the case where the groupoid G integrating A is not source-simply connected. Furthermore, we obtain a description of Hamiltonian spaces for Poisson groupoids and quasi-symplectic groupoids within this formalism.
{"title":"On the integration of Manin pairs","authors":"David Li-Bland, Eckhard Meinrenken","doi":"10.1016/j.difgeo.2025.102246","DOIUrl":"10.1016/j.difgeo.2025.102246","url":null,"abstract":"<div><div>It is a remarkable fact that the integrability of a Poisson manifold to a symplectic groupoid depends only on the integrability of its cotangent Lie algebroid <em>A</em>: The source-simply connected Lie groupoid <span><math><mi>G</mi><mo>⇉</mo><mi>M</mi></math></span> integrating <em>A</em> automatically acquires a multiplicative symplectic 2-form. More generally, a similar result holds for the integration of Lie bialgebroids to Poisson groupoids, as well as in the ‘quasi’ settings of Dirac structures and quasi-Lie bialgebroids. In this article, we will place these results into a general context of Manin pairs <span><math><mo>(</mo><mi>E</mi><mo>,</mo><mi>A</mi><mo>)</mo></math></span>, thereby obtaining a simple geometric approach to these integration results. We also clarify the case where the groupoid <em>G</em> integrating <em>A</em> is not source-simply connected. Furthermore, we obtain a description of Hamiltonian spaces for Poisson groupoids and quasi-symplectic groupoids within this formalism.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"99 ","pages":"Article 102246"},"PeriodicalIF":0.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-06-01Epub Date: 2025-02-27DOI: 10.1016/j.difgeo.2025.102238
Li Ou
In this paper, we investigate value distribution properties for Gauss maps of space-like stationary surfaces in four-dimensional Lorentz-Minkowski space , focusing on aspects such as the total weight of totally ramified values and unicity properties. We obtain not only general conclusions analogous to those in four-dimensional Euclidean space, but also results for space-like stationary surfaces with rational graphical Gauss image, which is an extension of degenerate space-like stationary surfaces.
{"title":"Ramification and unicity theorems for Gauss maps of complete space-like stationary surfaces in four-dimensional Lorentz-Minkowski space","authors":"Li Ou","doi":"10.1016/j.difgeo.2025.102238","DOIUrl":"10.1016/j.difgeo.2025.102238","url":null,"abstract":"<div><div>In this paper, we investigate value distribution properties for Gauss maps of space-like stationary surfaces in four-dimensional Lorentz-Minkowski space <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>3</mn><mo>,</mo><mn>1</mn></mrow></msup></math></span>, focusing on aspects such as the total weight of totally ramified values and unicity properties. We obtain not only general conclusions analogous to those in four-dimensional Euclidean space, but also results for space-like stationary surfaces with rational graphical Gauss image, which is an extension of degenerate space-like stationary surfaces.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"99 ","pages":"Article 102238"},"PeriodicalIF":0.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143510165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-06-01Epub Date: 2025-04-24DOI: 10.1016/j.difgeo.2025.102251
Phillip S. Harrington
For a relatively compact Stein domain Ω with boundary in a Hermitian manifold M, we consider the strong Diederich-Fornæss index, denoted : the supremum of all exponents such that eigenvalues of the complex Hessian of are bounded below by some positive multiple of on Ω for some defining function ρ. We will show that is completely characterized by the existence of a Hermitian metric with curvature terms satisfying a certain inequality when restricted to the null-space of the Levi-form.
{"title":"The strong Diederich-Fornæss index on C2 domains in Hermitian manifolds","authors":"Phillip S. Harrington","doi":"10.1016/j.difgeo.2025.102251","DOIUrl":"10.1016/j.difgeo.2025.102251","url":null,"abstract":"<div><div>For a relatively compact Stein domain Ω with <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> boundary in a Hermitian manifold <em>M</em>, we consider the strong Diederich-Fornæss index, denoted <span><math><mi>D</mi><mi>F</mi><mo>(</mo><mi>Ω</mi><mo>)</mo></math></span>: the supremum of all exponents <span><math><mn>0</mn><mo><</mo><mi>η</mi><mo><</mo><mn>1</mn></math></span> such that eigenvalues of the complex Hessian of <span><math><mo>−</mo><msup><mrow><mo>(</mo><mo>−</mo><mi>ρ</mi><mo>)</mo></mrow><mrow><mi>η</mi></mrow></msup></math></span> are bounded below by some positive multiple of <span><math><msup><mrow><mo>(</mo><mo>−</mo><mi>ρ</mi><mo>)</mo></mrow><mrow><mi>η</mi></mrow></msup></math></span> on Ω for some <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> defining function <em>ρ</em>. We will show that <span><math><mi>D</mi><mi>F</mi><mo>(</mo><mi>Ω</mi><mo>)</mo></math></span> is completely characterized by the existence of a Hermitian metric with curvature terms satisfying a certain inequality when restricted to the null-space of the Levi-form.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"99 ","pages":"Article 102251"},"PeriodicalIF":0.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-06-01Epub Date: 2025-02-05DOI: 10.1016/j.difgeo.2025.102234
Juanru Gu , Yao Lu , Hongwei Xu , Entao Zhao
Let be an oriented submanifold with parallel mean curvature vector in a complete simply connected Riemannian manifold . When the mean curvature , i.e., M is minimal, we prove that there exists a constant , such that if , and if M has a lower bound for Ricci curvature and an upper bound for scalar curvature, then is isometric to . Moreover, M is the totally geodesic sphere . This is a generalization of Shen and Li's results [10], [14]. When the ambient manifold is a space form, we improve the geometric rigidity theorem due to Xu-Gu [19] for the codimension is not more than 2 and .
{"title":"Curvature pinching for three-dimensional submanifolds in a Riemannian manifold","authors":"Juanru Gu , Yao Lu , Hongwei Xu , Entao Zhao","doi":"10.1016/j.difgeo.2025.102234","DOIUrl":"10.1016/j.difgeo.2025.102234","url":null,"abstract":"<div><div>Let <span><math><msup><mrow><mi>M</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span> be an oriented submanifold with parallel mean curvature vector in a complete simply connected Riemannian manifold <span><math><msup><mrow><mi>N</mi></mrow><mrow><mn>3</mn><mo>+</mo><mi>p</mi></mrow></msup></math></span>. When the mean curvature <span><math><mi>H</mi><mo>=</mo><mn>0</mn></math></span>, i.e., <em>M</em> is minimal, we prove that there exists a constant <span><math><msub><mrow><mi>δ</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>(</mo><mi>p</mi><mo>)</mo><mo>∈</mo><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>)</mo></math></span>, such that if <span><math><msub><mrow><mover><mrow><mi>K</mi></mrow><mo>‾</mo></mover></mrow><mrow><mi>N</mi></mrow></msub><mo>∈</mo><mo>[</mo><msub><mrow><mi>δ</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>(</mo><mi>p</mi><mo>)</mo><mo>,</mo><mn>1</mn><mo>]</mo></math></span>, and if <em>M</em> has a lower bound for Ricci curvature and an upper bound for scalar curvature, then <span><math><msup><mrow><mi>N</mi></mrow><mrow><mn>3</mn><mo>+</mo><mi>p</mi></mrow></msup></math></span> is isometric to <span><math><msup><mrow><mi>S</mi></mrow><mrow><mn>3</mn><mo>+</mo><mi>p</mi></mrow></msup></math></span>. Moreover, <em>M</em> is the totally geodesic sphere <span><math><msup><mrow><mi>S</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span>. This is a generalization of Shen and Li's results <span><span>[10]</span></span>, <span><span>[14]</span></span>. When the ambient manifold is a space form, we improve the geometric rigidity theorem due to Xu-Gu <span><span>[19]</span></span> for the codimension is not more than 2 and <span><math><mi>H</mi><mo>≠</mo><mn>0</mn></math></span>.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"99 ","pages":"Article 102234"},"PeriodicalIF":0.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-06-01Epub Date: 2025-03-09DOI: 10.1016/j.difgeo.2025.102241
Reza Bidar
Let G be a connected Lie group and a lattice. Connection curves of the homogeneous space are the orbits of one parameter subgroups of G. To block a pair of points is to find a finite set such that every connecting curve joining and intersects B. The homogeneous space M is blockable if every pair of points in M can be blocked, otherwise we call it non-blockable.
Sol is an important Lie group and one of the eight homogeneous Thurston 3-geometries. It is a unimodular solvable Lie group diffeomorphic to , and together with the left invariant metric includes copies of the hyperbolic plane, which makes studying its geometrical properties more interesting. In this paper we prove that all lattice quotients of Sol are non-blockable. In particular, we show that for any lattice , the set of non-blockable pairs is a dense subset of .
{"title":"Connection blocking in quotients of Sol","authors":"Reza Bidar","doi":"10.1016/j.difgeo.2025.102241","DOIUrl":"10.1016/j.difgeo.2025.102241","url":null,"abstract":"<div><div>Let <em>G</em> be a connected Lie group and <span><math><mi>Γ</mi><mo>⊂</mo><mi>G</mi></math></span> a lattice. Connection curves of the homogeneous space <span><math><mi>M</mi><mo>=</mo><mi>G</mi><mo>/</mo><mi>Γ</mi></math></span> are the orbits of one parameter subgroups of <em>G</em>. To <em>block</em> a pair of points <span><math><msub><mrow><mi>m</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><msub><mrow><mi>m</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>∈</mo><mi>M</mi></math></span> is to find a <em>finite</em> set <span><math><mi>B</mi><mo>⊂</mo><mi>M</mi><mo>∖</mo><mo>{</mo><msub><mrow><mi>m</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><msub><mrow><mi>m</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>}</mo></math></span> such that every connecting curve joining <span><math><msub><mrow><mi>m</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>m</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> intersects <em>B</em>. The homogeneous space <em>M</em> is <em>blockable</em> if every pair of points in <em>M</em> can be blocked, otherwise we call it <em>non-blockable</em>.</div><div><em>Sol</em> is an important Lie group and one of the eight homogeneous Thurston 3-geometries. It is a unimodular solvable Lie group diffeomorphic to <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span>, and together with the left invariant metric <span><math><mi>d</mi><msup><mrow><mi>s</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>=</mo><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo><mn>2</mn><mi>z</mi></mrow></msup><mi>d</mi><msup><mrow><mi>x</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>+</mo><msup><mrow><mi>e</mi></mrow><mrow><mn>2</mn><mi>z</mi></mrow></msup><mi>d</mi><msup><mrow><mi>y</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>+</mo><mi>d</mi><msup><mrow><mi>z</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> includes copies of the hyperbolic plane, which makes studying its geometrical properties more interesting. In this paper we prove that all lattice quotients of <em>Sol</em> are non-blockable. In particular, we show that for any lattice <span><math><mi>Γ</mi><mo>⊂</mo><mi>S</mi><mi>o</mi><mi>l</mi></math></span>, the set of non-blockable pairs is a dense subset of <span><math><mi>S</mi><mi>o</mi><mi>l</mi><mo>/</mo><mi>Γ</mi><mo>×</mo><mi>S</mi><mi>o</mi><mi>l</mi><mo>/</mo><mi>Γ</mi></math></span>.</div></div>","PeriodicalId":51010,"journal":{"name":"Differential Geometry and its Applications","volume":"99 ","pages":"Article 102241"},"PeriodicalIF":0.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}