{"title":"Weak solutions to the Navier–Stokes equations for steady compressible non-Newtonian fluids","authors":"Cosmin Burtea , Maja Szlenk","doi":"10.1016/j.na.2025.113774","DOIUrl":"10.1016/j.na.2025.113774","url":null,"abstract":"<div><div>We prove the existence of weak solutions for the steady Navier–Stokes system for compressible non-Newtonian fluids on a bounded, two- or three-dimensional domain. Assuming the viscous stress tensor is monotone satisfying a power-law growth with power <span><math><mi>r</mi></math></span> and the pressure is given by <span><math><msup><mrow><mi>ϱ</mi></mrow><mrow><mi>γ</mi></mrow></msup></math></span>, we construct a solution provided that <span><math><mrow><mi>r</mi><mo>></mo><mfrac><mrow><mn>3</mn><mi>d</mi></mrow><mrow><mi>d</mi><mo>+</mo><mn>2</mn></mrow></mfrac></mrow></math></span> and <span><math><mi>γ</mi></math></span> is sufficiently large, depending on the values of <span><math><mi>r</mi></math></span>. Additionally, we also show the existence for time-discretized model for Herschel–Bulkley fluids, where the viscosity has a singular part.</div></div>","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113774"},"PeriodicalIF":1.3,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143388285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Combinatorial curvature flows for generalized hyperbolic circle packings on surfaces","authors":"Te Ba , Chao Zheng","doi":"10.1016/j.na.2025.113773","DOIUrl":"10.1016/j.na.2025.113773","url":null,"abstract":"<div><div>Generalized hyperbolic circle packings were introduced in Ba et al. (2023) as the generalization of tangential circle packings in hyperbolic background geometry. To find generalized hyperbolic circle packings on surfaces with prescribed total geodesic curvatures, we introduce the combinatorial Calabi flow, the fractional combinatorial Calabi flow and the combinatorial <span><math><mi>p</mi></math></span>th Calabi flow for generalized hyperbolic circle packings on surfaces. We establish several equivalent conditions regarding the longtime behaviors of these combinatorial curvature flows. This provides effective algorithms for finding the generalized hyperbolic circle packings with prescribed total geodesic curvatures on surfaces.</div></div>","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113773"},"PeriodicalIF":1.3,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Razvan Gabriel Iagar, Ana Isabel Muñoz, Ariel Sánchez
{"title":"Extinction and non-extinction profiles for the sub-critical fast diffusion equation with weighted source","authors":"Razvan Gabriel Iagar, Ana Isabel Muñoz, Ariel Sánchez","doi":"10.1016/j.na.2025.113772","DOIUrl":"10.1016/j.na.2025.113772","url":null,"abstract":"<div><div>We establish both extinction and non-extinction self-similar profiles for the following fast diffusion equation with a weighted source term <span><math><mrow><msub><mrow><mi>∂</mi></mrow><mrow><mi>t</mi></mrow></msub><mi>u</mi><mo>=</mo><mi>Δ</mi><msup><mrow><mi>u</mi></mrow><mrow><mi>m</mi></mrow></msup><mo>+</mo><msup><mrow><mrow><mo>|</mo><mi>x</mi><mo>|</mo></mrow></mrow><mrow><mi>σ</mi></mrow></msup><msup><mrow><mi>u</mi></mrow><mrow><mi>p</mi></mrow></msup><mo>,</mo></mrow></math></span> posed for <span><math><mrow><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo></mrow><mo>∈</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>N</mi></mrow></msup><mo>×</mo><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow></mrow></math></span>, <span><math><mrow><mi>N</mi><mo>≥</mo><mspace></mspace><mn>3</mn></mrow></math></span>, in the sub-critical range of the fast diffusion equation <span><math><mrow><mn>0</mn><mo><</mo><mi>m</mi><mo><</mo><msub><mrow><mi>m</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>=</mo><mrow><mo>(</mo><mi>N</mi><mo>−</mo><mn>2</mn><mo>)</mo></mrow><mo>/</mo><mi>N</mi></mrow></math></span>. We consider <span><math><mrow><mi>σ</mi><mo>></mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mo>max</mo><mrow><mo>{</mo><msub><mrow><mi>p</mi></mrow><mrow><mi>c</mi></mrow></msub><mrow><mo>(</mo><mi>σ</mi><mo>)</mo></mrow><mo>,</mo><mn>1</mn><mo>}</mo></mrow><mo><</mo><mi>p</mi><mo><</mo><msub><mrow><mi>p</mi></mrow><mrow><mi>L</mi></mrow></msub><mrow><mo>(</mo><mi>σ</mi><mo>)</mo></mrow></mrow></math></span>, where <span><math><mrow><msub><mrow><mi>p</mi></mrow><mrow><mi>c</mi></mrow></msub><mrow><mo>(</mo><mi>σ</mi><mo>)</mo></mrow><mo>=</mo><mfrac><mrow><mi>m</mi><mrow><mo>(</mo><mi>N</mi><mo>+</mo><mi>σ</mi><mo>)</mo></mrow></mrow><mrow><mi>N</mi><mo>−</mo><mn>2</mn></mrow></mfrac><mo>,</mo><mspace></mspace><msub><mrow><mi>p</mi></mrow><mrow><mi>L</mi></mrow></msub><mrow><mo>(</mo><mi>σ</mi><mo>)</mo></mrow><mo>=</mo><mn>1</mn><mo>+</mo><mfrac><mrow><mi>σ</mi><mrow><mo>(</mo><mn>1</mn><mo>−</mo><mi>m</mi><mo>)</mo></mrow></mrow><mrow><mn>2</mn></mrow></mfrac><mo>.</mo></mrow></math></span> We show that, on the one hand, positive self-similar solutions at any time <span><math><mrow><mi>t</mi><mo>></mo><mn>0</mn></mrow></math></span>, in the form <span><math><mrow><mi>u</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo></mrow><mo>=</mo><msup><mrow><mi>t</mi></mrow><mrow><mi>α</mi></mrow></msup><mi>f</mi><mrow><mo>(</mo><mrow><mo>|</mo><mi>x</mi><mo>|</mo></mrow><msup><mrow><mi>t</mi></mrow><mrow><mi>β</mi></mrow></msup><mo>)</mo></mrow><mo>,</mo><mspace></mspace><mi>f</mi><mrow><mo>(</mo><mi>ξ</mi><mo>)</mo></mrow><mo>∼</mo><mi>C</mi><msup><mrow><mi>ξ</mi></mrow><mrow><mo>−</mo><mrow><mo>(</mo><mi>N</mi><mo>−</mo><mn>2</mn><mo>)</mo></mrow><mo>/</mo><mi>m</mi></mrow></msup><mo>,</mo><mspace></mspace><mi>α</mi><mo>></mo><mn>0</mn><mo>,</mo><mspace></mspace><mi>β</mi><mo>></mo><mn","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113772"},"PeriodicalIF":1.3,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anna Maria Candela , Kanishka Perera , Addolorata Salvatore
{"title":"Existence results for a borderline case of a class of p-Laplacian problems","authors":"Anna Maria Candela , Kanishka Perera , Addolorata Salvatore","doi":"10.1016/j.na.2025.113762","DOIUrl":"10.1016/j.na.2025.113762","url":null,"abstract":"<div><div>The aim of this paper is investigating the existence of at least one nontrivial bounded solution of the new asymptotically “linear” problem <span><span><span><math><mfenced><mrow><mtable><mtr><mtd><mo>−</mo><mo>div</mo><mfenced><mrow><mfenced><mrow><msub><mrow><mi>A</mi></mrow><mrow><mn>0</mn></mrow></msub><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>+</mo><mi>A</mi><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><msup><mrow><mrow><mo>|</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mi>p</mi><mi>s</mi></mrow></msup></mrow></mfenced><msup><mrow><mrow><mo>|</mo><mo>∇</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mi>p</mi><mo>−</mo><mn>2</mn></mrow></msup><mo>∇</mo><mi>u</mi></mrow></mfenced><mo>+</mo><mi>s</mi><mspace></mspace><mi>A</mi><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><msup><mrow><mrow><mo>|</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mi>p</mi><mi>s</mi><mo>−</mo><mn>2</mn></mrow></msup><mi>u</mi><mspace></mspace><msup><mrow><mrow><mo>|</mo><mo>∇</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mi>p</mi></mrow></msup></mtd></mtr><mtr><mtd><mspace></mspace><mspace></mspace><mspace></mspace><mo>=</mo><mspace></mspace><mi>μ</mi><msup><mrow><mrow><mo>|</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mi>p</mi><mrow><mo>(</mo><mi>s</mi><mo>+</mo><mn>1</mn><mo>)</mo></mrow><mo>−</mo><mn>2</mn></mrow></msup><mi>u</mi><mo>+</mo><mi>g</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>u</mi><mo>)</mo></mrow></mtd><mtd><mtext>in</mtext><mi>Ω</mi><mtext>,</mtext></mtd></mtr><mtr><mtd><mi>u</mi><mo>=</mo><mn>0</mn></mtd><mtd><mtext>on</mtext><mi>∂</mi><mi>Ω</mi><mtext>,</mtext></mtd></mtr></mtable></mrow></mfenced></math></span></span></span>where <span><math><mi>Ω</mi></math></span> is a bounded domain in <span><math><msup><mrow><mi>R</mi></mrow><mrow><mi>N</mi></mrow></msup></math></span>, <span><math><mrow><mi>N</mi><mo>≥</mo><mn>2</mn></mrow></math></span>, <span><math><mrow><mn>1</mn><mo><</mo><mi>p</mi><mo><</mo><mi>N</mi></mrow></math></span>, <span><math><mrow><mi>s</mi><mo>></mo><mn>1</mn><mo>/</mo><mi>p</mi></mrow></math></span>, both the coefficients <span><math><mrow><msub><mrow><mi>A</mi></mrow><mrow><mn>0</mn></mrow></msub><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow></mrow></math></span> and <span><math><mrow><mi>A</mi><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow></mrow></math></span> are in <span><math><mrow><msup><mrow><mi>L</mi></mrow><mrow><mi>∞</mi></mrow></msup><mrow><mo>(</mo><mi>Ω</mi><mo>)</mo></mrow></mrow></math></span> and far away from 0, <span><math><mrow><mi>μ</mi><mo>∈</mo><mi>R</mi></mrow></math></span>, and the “perturbation” term <span><math><mrow><mi>g</mi><mrow><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo></mrow></mrow></math></span> is a Carathéodory function on <span><math><mrow><mi>Ω</mi><mo>×</mo><mi>R</mi></mrow></math></span> which grows as <span><math><msup><mrow><mrow><mo>|</mo><mi>t</mi><mo>|</mo></mrow></mrow><mrow><mi>r</mi><mo>−</mo><mn>1</mn></mrow></msup></math></span> with <span><math><mrow><mn>1</m","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113762"},"PeriodicalIF":1.3,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143265967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Variational integrals on Hessian spaces: Partial regularity for critical points","authors":"Arunima Bhattacharya , Anna Skorobogatova","doi":"10.1016/j.na.2025.113760","DOIUrl":"10.1016/j.na.2025.113760","url":null,"abstract":"<div><div>We develop regularity theory for critical points of variational integrals defined on Hessian spaces of functions on open, bounded subdomains of <span><math><msup><mrow><mi>R</mi></mrow><mrow><mi>n</mi></mrow></msup></math></span>, under compactly supported variations. We show that for smooth convex functionals, a <span><math><msup><mrow><mi>W</mi></mrow><mrow><mn>2</mn><mo>,</mo><mi>∞</mi></mrow></msup></math></span> critical point with bounded Hessian is smooth provided that its Hessian has a small bounded mean oscillation (BMO). We deduce that the interior singular set of a critical point has Hausdorff dimension at most <span><math><mrow><mi>n</mi><mo>−</mo><msub><mrow><mi>p</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow></math></span>, for some <span><math><mrow><msub><mrow><mi>p</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>∈</mo><mrow><mo>(</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>)</mo></mrow></mrow></math></span>. We state some applications of our results to variational problems in Lagrangian geometry. Finally, we use the Hamiltonian stationary equation to demonstrate the importance of our assumption on the a priori regularity of the critical point.</div></div>","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113760"},"PeriodicalIF":1.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143268147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Local uniqueness of minimizers for Choquard type equations","authors":"Lintao Liu , Kaimin Teng , Shuai Yuan","doi":"10.1016/j.na.2025.113764","DOIUrl":"10.1016/j.na.2025.113764","url":null,"abstract":"<div><div>We consider <span><math><msup><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span>-constraint minimizers of the Choquard energy functional with a trapping potential <span><math><mrow><mi>V</mi><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>=</mo><msup><mrow><mrow><mo>|</mo><mi>x</mi><mo>|</mo></mrow></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span>. It is known that positive minimizers exist if and only if the parameter <span><math><mi>a</mi></math></span> satisfies <span><math><mrow><mi>a</mi><mo><</mo><msup><mrow><mi>a</mi></mrow><mrow><mo>∗</mo></mrow></msup><mo>≔</mo><msubsup><mrow><mo>‖</mo><mi>Q</mi><mo>‖</mo></mrow><mrow><mn>2</mn></mrow><mrow><mn>2</mn></mrow></msubsup></mrow></math></span>, where <span><math><mi>Q</mi></math></span> is the unique positive radial solution of <span><math><mrow><mo>−</mo><mi>Δ</mi><mi>u</mi><mo>+</mo><mi>u</mi><mo>−</mo><msup><mrow><mrow><mo>|</mo><mi>u</mi><mo>|</mo></mrow></mrow><mrow><mfrac><mrow><mn>4</mn></mrow><mrow><mn>3</mn></mrow></mfrac></mrow></msup><mi>u</mi><mo>=</mo><mn>0</mn></mrow></math></span> in <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span>. This paper focuses on the local uniqueness of minimizers by using energy estimates, blow-up analysis and establishing the Pohozăev identity.</div></div>","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113764"},"PeriodicalIF":1.3,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143163859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fujita exponent and blow-up rate for a mixed local and nonlocal heat equation","authors":"Leandro M. Del Pezzo , Raúl Ferreira","doi":"10.1016/j.na.2025.113761","DOIUrl":"10.1016/j.na.2025.113761","url":null,"abstract":"<div><div>In this paper we consider the blow-up problem for a mixed local-nonlocal diffusion operator, <span><span><span><math><mrow><msub><mrow><mi>u</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mi>a</mi><mi>Δ</mi><mi>u</mi><mo>−</mo><mi>b</mi><msup><mrow><mrow><mo>(</mo><mo>−</mo><mi>Δ</mi><mo>)</mo></mrow></mrow><mrow><mi>s</mi></mrow></msup><mi>u</mi><mo>+</mo><msup><mrow><mi>u</mi></mrow><mrow><mi>p</mi></mrow></msup></mrow></math></span></span></span>We show that the Fujita exponent is given by the nonlocal part, <span><math><mrow><msub><mrow><mi>p</mi></mrow><mrow><mi>F</mi></mrow></msub><mo>=</mo><mn>1</mn><mo>+</mo><mn>2</mn><mi>s</mi><mo>/</mo><mi>N</mi></mrow></math></span>. We also determinate, in some cases, the blow-up rate.</div></div>","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113761"},"PeriodicalIF":1.3,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Extremal functions for twisted sharp Sobolev inequalities with lower order remainder terms","authors":"Olivier Druet , Emmanuel Hebey","doi":"10.1016/j.na.2025.113758","DOIUrl":"10.1016/j.na.2025.113758","url":null,"abstract":"<div><div>We prove existence of extremal functions and compactness of the set of extremal functions for twisted sharp 4-dimensional Sobolev inequalities with lower order remainder terms.</div></div>","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113758"},"PeriodicalIF":1.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sylvester Eriksson-Bique , Andrea Pinamonti , Gareth Speight
{"title":"Universal differentiability sets in Laakso space","authors":"Sylvester Eriksson-Bique , Andrea Pinamonti , Gareth Speight","doi":"10.1016/j.na.2025.113752","DOIUrl":"10.1016/j.na.2025.113752","url":null,"abstract":"<div><div>We show that there exists a family of mutually singular doubling measures on Laakso space with respect to which real-valued Lipschitz functions are almost everywhere differentiable. This implies that there exists a measure zero universal differentiability set in Laakso space. Additionally, we show that each of the measures constructed supports a Poincaré inequality.</div></div>","PeriodicalId":49749,"journal":{"name":"Nonlinear Analysis-Theory Methods & Applications","volume":"255 ","pages":"Article 113752"},"PeriodicalIF":1.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}