{"title":"Theta liftings for (GLn,GLn) type dual pairs of loop groups","authors":"Yanze Chen , Yongchang Zhu","doi":"10.1016/j.aim.2025.110417","DOIUrl":"10.1016/j.aim.2025.110417","url":null,"abstract":"<div><div>In this article we prove the theta liftings of a cusp form on the loop <span><math><msub><mrow><mi>GL</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span> group over <span><math><mi>Q</mi></math></span> induced from a classical cusp form for the loop group version of the “dual pair” <span><math><mo>(</mo><msub><mrow><mi>GL</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>,</mo><msub><mrow><mi>GL</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo></math></span> is an Eisenstein series.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110417"},"PeriodicalIF":1.5,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144491074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Chow ring of the universal Picard stack over the hyperelliptic locus","authors":"Hannah Larson","doi":"10.1016/j.aim.2025.110412","DOIUrl":"10.1016/j.aim.2025.110412","url":null,"abstract":"<div><div>Let <span><math><msubsup><mrow><mi>J</mi></mrow><mrow><mi>g</mi></mrow><mrow><mi>d</mi></mrow></msubsup><mo>→</mo><msub><mrow><mi>M</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span> be the universal Picard stack parametrizing degree <em>d</em> line bundles on genus <em>g</em> curves, and let <span><math><msubsup><mrow><mi>J</mi></mrow><mrow><mn>2</mn><mo>,</mo><mi>g</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span> be its restriction to locus of hyperelliptic curves <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>2</mn><mo>,</mo><mi>g</mi></mrow></msub><mo>⊂</mo><msub><mrow><mi>M</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span>. We determine the rational Chow ring of <span><math><msubsup><mrow><mi>J</mi></mrow><mrow><mn>2</mn><mo>,</mo><mi>g</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span> for all <em>d</em> and <em>g</em>. In particular, we prove it is generated by restrictions of tautological classes on <span><math><msubsup><mrow><mi>J</mi></mrow><mrow><mi>g</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span> and we determine all relations among the restrictions of such classes. We also compute the integral Picard group of <span><math><msubsup><mrow><mi>J</mi></mrow><mrow><mn>2</mn><mo>,</mo><mi>g</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span>, completing (and extending the <span><math><msub><mrow><mi>PGL</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span>-equivariant case) prior work of Erman and Wood. As a corollary, we prove that <span><math><msubsup><mrow><mi>J</mi></mrow><mrow><mn>2</mn><mo>,</mo><mi>g</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span> is either a trivial <span><math><msub><mrow><mi>G</mi></mrow><mrow><mi>m</mi></mrow></msub></math></span>-gerbe over its rigidification, or has Brauer class of order 2, depending on the parity of <span><math><mi>d</mi><mo>−</mo><mi>g</mi></math></span>.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"479 ","pages":"Article 110412"},"PeriodicalIF":1.5,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144490329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Intersection probabilities for flats in hyperbolic space","authors":"Ercan Sönmez, Panagiotis Spanos, Christoph Thäle","doi":"10.1016/j.aim.2025.110415","DOIUrl":"10.1016/j.aim.2025.110415","url":null,"abstract":"<div><div>Consider the <em>d</em>-dimensional hyperbolic space <span><math><msubsup><mrow><mi>M</mi></mrow><mrow><mi>K</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span> of constant curvature <span><math><mi>K</mi><mo><</mo><mn>0</mn></math></span> and fix a point <em>o</em> playing the role of an origin. Let <strong>L</strong> be a uniform random <em>q</em>-dimensional totally geodesic submanifold (called <em>q</em>-flat) in <span><math><msubsup><mrow><mi>M</mi></mrow><mrow><mi>K</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span> passing through <em>o</em> and, independently of <strong>L</strong>, let <strong>E</strong> be a random <span><math><mo>(</mo><mi>d</mi><mo>−</mo><mi>q</mi><mo>+</mo><mi>γ</mi><mo>)</mo></math></span>-flat in <span><math><msubsup><mrow><mi>M</mi></mrow><mrow><mi>K</mi></mrow><mrow><mi>d</mi></mrow></msubsup></math></span> which is uniformly distributed in the set of all <span><math><mo>(</mo><mi>d</mi><mo>−</mo><mi>q</mi><mo>+</mo><mi>γ</mi><mo>)</mo></math></span>-flats intersecting a hyperbolic ball of radius <span><math><mi>u</mi><mo>></mo><mn>0</mn></math></span> around <em>o</em>. We are interested in the distribution of the random <em>γ</em>-flat arising as the intersection of <strong>E</strong> with <strong>L</strong>. In contrast to the Euclidean case, the intersection <span><math><mi>E</mi><mo>∩</mo><mi>L</mi></math></span> can be empty with strictly positive probability. We determine this probability and the full distribution of <span><math><mi>E</mi><mo>∩</mo><mi>L</mi></math></span>. Thereby, we elucidate crucial differences to the Euclidean case. Moreover, we study the limiting behavior as <span><math><mi>d</mi><mo>↑</mo><mo>∞</mo></math></span> and also <span><math><mi>K</mi><mo>↑</mo><mn>0</mn></math></span>. Thereby we obtain a phase transition with three different phases which we completely characterize, including a critical phase with distinctive behavior and a phase recovering the Euclidean results. In the background are methods from hyperbolic integral geometry.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"479 ","pages":"Article 110415"},"PeriodicalIF":1.5,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144490327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Riesz-type calculus for Lorentz-Morrey spaces","authors":"Liguang Liu , Jie Xiao","doi":"10.1016/j.aim.2025.110414","DOIUrl":"10.1016/j.aim.2025.110414","url":null,"abstract":"<div><div>This paper is devoted to a highly nontrivial study of <span><math><mo>(</mo><mn>0</mn><mo>,</mo><mi>n</mi><mo>]</mo><mo>∋</mo><mi>α</mi></math></span>-order Fourier transform-based Riesz integral-differential calculus for Lorentz-Morrey spaces (covering Lebesgue spaces): (i) Riesz integral traces of Lorentz-Morrey spaces; (ii) Riesz differential equations in dual Lorentz-Morrey spaces; (iii) Riesz variational capacities for Lorentz-Morrey spaces.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110414"},"PeriodicalIF":1.5,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144491075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Robert J. McCann , Cale Rankin , Kelvin Shuangjian Zhang
{"title":"C1,1 regularity for principal-agent problems","authors":"Robert J. McCann , Cale Rankin , Kelvin Shuangjian Zhang","doi":"10.1016/j.aim.2025.110396","DOIUrl":"10.1016/j.aim.2025.110396","url":null,"abstract":"<div><div>We prove the interior <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>1</mn></mrow></msup></math></span> regularity of the indirect utilities which solve a subclass of principal-agent problems originally considered by Figalli, Kim, and McCann. Our approach is based on construction of a suitable comparison function which, essentially, allows one to pinch the solution between parabolas. The original ideas for this proof arise from an earlier, unpublished, result of Caffarelli and Lions for bilinear preferences which we extend here to general quasilinear benefit functions. We give a simple example which shows the <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>1</mn></mrow></msup></math></span> regularity is optimal.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110396"},"PeriodicalIF":1.5,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144471689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantitative Runge type approximation theorems for zero solutions of certain partial differential operators","authors":"A. Debrouwere , T. Kalmes","doi":"10.1016/j.aim.2025.110413","DOIUrl":"10.1016/j.aim.2025.110413","url":null,"abstract":"<div><div>We prove quantitative Runge type approximation results for spaces of smooth zero solutions of several classes of linear partial differential operators with constant coefficients. Among others, we establish such results for arbitrary operators on convex sets, elliptic operators, parabolic operators, and the wave operator in one spatial variable. Our methods are inspired by the study of linear topological invariants for kernels of partial differential operators. As a part of our work, we also show a qualitative Runge type approximation theorem for subspace elliptic operators, which seems to be new and of independent interest.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110413"},"PeriodicalIF":1.5,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144471690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael Allen , Brian Grove , Ling Long, Fang-Ting Tu
{"title":"The explicit hypergeometric-modularity method I","authors":"Michael Allen , Brian Grove , Ling Long, Fang-Ting Tu","doi":"10.1016/j.aim.2025.110411","DOIUrl":"10.1016/j.aim.2025.110411","url":null,"abstract":"<div><div>The theories of hypergeometric functions and modular forms are highly intertwined. For example, particular values of truncated hypergeometric functions and hypergeometric character sums are often congruent or equal to Fourier coefficients of modular forms. In this series of papers, we develop and explore an explicit “Hypergeometric-Modularity” method for associating a modular form to a given hypergeometric datum. In particular, for certain length three and four hypergeometric data we give an explicit method for finding a modular form <em>f</em> such that the corresponding hypergeometric Galois representation has a subrepresentation isomorphic to the Deligne representation of <em>f</em>. Our method utilizes Ramanujan's theory of elliptic functions to alternative bases, commutative formal group laws, and supercongruences. As a byproduct, we give a collection of eta quotients with multiplicative coefficients constructed from hypergeometric functions. In the second paper, we discuss a number of applications, including explicit connections between hypergeometric values and periods of these explicit eta quotients as well as evaluation formulae for certain special <em>L</em>-values.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110411"},"PeriodicalIF":1.5,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
William Alexandre , Clifford Gilmore , Sophie Grivaux
{"title":"Typicality of operators on Fréchet algebras admitting a hypercyclic algebra","authors":"William Alexandre , Clifford Gilmore , Sophie Grivaux","doi":"10.1016/j.aim.2025.110406","DOIUrl":"10.1016/j.aim.2025.110406","url":null,"abstract":"<div><div>This paper is devoted to the study of typical properties (in the Baire Category sense) of certain classes of continuous linear operators acting on Fréchet algebras, endowed with the topology of pointwise convergence. Our main results show that within natural Polish spaces of continuous operators acting on the algebra <span><math><mi>H</mi><mo>(</mo><mi>C</mi><mo>)</mo></math></span> of entire functions on <span><math><mi>C</mi></math></span>, a typical operator supports a hypercyclic algebra. We also investigate the case of the complex Fréchet algebras <span><math><mi>X</mi><mo>=</mo><msub><mrow><mi>ℓ</mi></mrow><mrow><mi>p</mi></mrow></msub><mo>(</mo><mi>N</mi><mo>)</mo></math></span>, <span><math><mn>1</mn><mo>≤</mo><mi>p</mi><mo><</mo><mo>+</mo><mo>∞</mo></math></span>, or <span><math><mi>X</mi><mo>=</mo><msub><mrow><mi>c</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>(</mo><mi>N</mi><mo>)</mo></math></span> endowed with the coordinatewise product, and show that whenever <span><math><mi>M</mi><mo>></mo><mn>1</mn></math></span>, a typical operator on <em>X</em> of norm less than or equal to <em>M</em> admits a hypercyclic algebra.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110406"},"PeriodicalIF":1.5,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Sharp estimates for the Cramér transform of log-concave measures and geometric applications","authors":"Silouanos Brazitikos , Giorgos Chasapis","doi":"10.1016/j.aim.2025.110407","DOIUrl":"10.1016/j.aim.2025.110407","url":null,"abstract":"<div><div>We establish a new comparison between the Legendre transform of the cumulant generating function and the half-space depth of an arbitrary log-concave probability distribution on the real line, that carries on to the multidimensional setting. Combined with sharp estimates for the Cramér transform of rotationally invariant measures, we are led to some new phase-transition type results for the asymptotics of the expected measure of random polytopes. As a byproduct of our analysis, we address a question on the sharp exponential separability constant for log-concave distributions, in the symmetric case.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110407"},"PeriodicalIF":1.5,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144313438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"CMC hypersurface with finite index in hyperbolic space H4","authors":"Han Hong","doi":"10.1016/j.aim.2025.110408","DOIUrl":"10.1016/j.aim.2025.110408","url":null,"abstract":"<div><div>In this paper, we prove that there are no complete noncompact constant mean curvature hypersurfaces with the mean curvature <span><math><mi>H</mi><mo>></mo><mn>1</mn></math></span>, finite index and finite topology in hyperbolic space <span><math><msup><mrow><mi>H</mi></mrow><mrow><mn>4</mn></mrow></msup></math></span>. A more general nonexistence result can be proved in a 4-dimensional Riemannian manifold with certain curvature conditions. We also show that 4-manifold with <span><math><mi>Ric</mi><mo>></mo><mn>1</mn></math></span> does not contain any complete noncompact minimal stable hypersurface with finite topology.</div><div>The proof relies on the <em>μ</em>-bubble initially introduced by Gromov and further developed by Chodosh-Li-Stryker in the context of stable minimal hypersurfaces.</div></div>","PeriodicalId":50860,"journal":{"name":"Advances in Mathematics","volume":"478 ","pages":"Article 110408"},"PeriodicalIF":1.5,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}