Pub Date : 2025-09-30DOI: 10.1016/j.matpur.2025.103806
Juhi Jang , Jiaqi Liu , Nader Masmoudi
In this article, we construct a continuum family of self-similar waiting time solutions for the one-dimensional compressible Euler equations for the adiabatic exponent in the half-line with the vacuum boundary. The solutions are confined by a stationary vacuum interface for a finite time with at least regularity of the velocity and the sound speed up to the boundary. Subsequently, the solutions undergo the change of the behavior, becoming only Hölder continuous near the singular point, and simultaneously transition to the solutions to the vacuum moving boundary Euler equations satisfying the physical vacuum condition. When the boundary starts moving, a weak discontinuity emanating from the singular point along the sonic curve emerges. The solutions are locally smooth in the interior region away from the vacuum boundary and the sonic curve.
{"title":"Waiting time solutions in gas dynamics","authors":"Juhi Jang , Jiaqi Liu , Nader Masmoudi","doi":"10.1016/j.matpur.2025.103806","DOIUrl":"10.1016/j.matpur.2025.103806","url":null,"abstract":"<div><div>In this article, we construct a continuum family of self-similar waiting time solutions for the one-dimensional compressible Euler equations for the adiabatic exponent <span><math><mi>γ</mi><mo>∈</mo><mo>(</mo><mn>1</mn><mo>,</mo><mn>3</mn><mo>)</mo></math></span> in the half-line with the vacuum boundary. The solutions are confined by a stationary vacuum interface for a finite time with at least <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span> regularity of the velocity and the sound speed up to the boundary. Subsequently, the solutions undergo the change of the behavior, becoming only Hölder continuous near the singular point, and simultaneously transition to the solutions to the vacuum moving boundary Euler equations satisfying the physical vacuum condition. When the boundary starts moving, a weak discontinuity emanating from the singular point along the sonic curve emerges. The solutions are locally smooth in the interior region away from the vacuum boundary and the sonic curve.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"204 ","pages":"Article 103806"},"PeriodicalIF":2.3,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264964","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}
Pub Date : 2025-09-30DOI: 10.1016/j.matpur.2025.103802
Guofang Wang , Chao Xia , Xuwen Zhang
In this paper, we establish monotonicity formulas for capillary surfaces in the half-space and in the unit ball and extend the result of Volkmann (2016) [27] for surfaces with free boundary. As applications, we obtain Li-Yau-type inequalities for the Willmore energy of capillary surfaces, and extend Fraser-Schoen's optimal area estimate for minimal free boundary surfaces in (2011) [10] to the capillary setting, which is different to another optimal area estimate proved by Brendle (2023) [5].
{"title":"Monotonicity formulas for capillary surfaces","authors":"Guofang Wang , Chao Xia , Xuwen Zhang","doi":"10.1016/j.matpur.2025.103802","DOIUrl":"10.1016/j.matpur.2025.103802","url":null,"abstract":"<div><div>In this paper, we establish monotonicity formulas for capillary surfaces in the half-space <span><math><msubsup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow><mrow><mn>3</mn></mrow></msubsup></math></span> and in the unit ball <span><math><msup><mrow><mi>B</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span> and extend the result of Volkmann (2016) <span><span>[27]</span></span> for surfaces with free boundary. As applications, we obtain Li-Yau-type inequalities for the Willmore energy of capillary surfaces, and extend Fraser-Schoen's optimal area estimate for minimal free boundary surfaces in <span><math><msup><mrow><mi>B</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span> (2011) <span><span>[10]</span></span> to the capillary setting, which is different to another optimal area estimate proved by Brendle (2023) <span><span>[5]</span></span>.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"204 ","pages":"Article 103802"},"PeriodicalIF":2.3,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145219417","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}
Pub Date : 2025-09-30DOI: 10.1016/j.matpur.2025.103799
Bernard Helffer, François Nicoleau
In this paper, we analyze the magnetic Dirichlet-to-Neumann operator (D-to-N map) on the exterior of the disk with respect to a magnetic potential where, for and , and is the Aharonov-Bohm potential centered at the origin of flux . First, we show that the limit of as is equal to the D-to-N map on the interior of the disk associated with the potential . Secondly, we study the ground state energy of the D-to-N map and show that the strong diamagnetism property holds. Finally we slightly extend to the exterior case the asymptotic results as obtained in the interior case for general domains.
{"title":"On the magnetic Dirichlet to Neumann operator on the exterior of the disk – Diamagnetism, weak-magnetic field limit and flux effects","authors":"Bernard Helffer, François Nicoleau","doi":"10.1016/j.matpur.2025.103799","DOIUrl":"10.1016/j.matpur.2025.103799","url":null,"abstract":"<div><div>In this paper, we analyze the magnetic Dirichlet-to-Neumann operator (D-to-N map) <span><math><mover><mrow><mi>Λ</mi></mrow><mrow><mo>ˇ</mo></mrow></mover><mo>(</mo><mi>b</mi><mo>,</mo><mi>ν</mi><mo>)</mo></math></span> on the exterior of the disk with respect to a magnetic potential <span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>b</mi><mo>,</mo><mi>ν</mi></mrow></msub><mo>=</mo><msup><mrow><mi>A</mi></mrow><mrow><mi>b</mi></mrow></msup><mo>+</mo><msub><mrow><mi>A</mi></mrow><mrow><mi>ν</mi></mrow></msub></math></span> where, for <span><math><mi>b</mi><mo>∈</mo><mi>R</mi></math></span> and <span><math><mi>ν</mi><mo>∈</mo><mi>R</mi></math></span>, <span><math><msup><mrow><mi>A</mi></mrow><mrow><mi>b</mi></mrow></msup><mo>(</mo><mi>x</mi><mo>,</mo><mi>y</mi><mo>)</mo><mo>=</mo><mi>b</mi><mspace></mspace><mo>(</mo><mo>−</mo><mi>y</mi><mo>,</mo><mi>x</mi><mo>)</mo></math></span> and <span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>ν</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>y</mi><mo>)</mo></math></span> is the Aharonov-Bohm potential centered at the origin of flux <span><math><mn>2</mn><mi>π</mi><mi>ν</mi></math></span>. First, we show that the limit of <span><math><mover><mrow><mi>Λ</mi></mrow><mrow><mo>ˇ</mo></mrow></mover><mo>(</mo><mi>b</mi><mo>,</mo><mi>ν</mi><mo>)</mo></math></span> as <span><math><mi>b</mi><mo>→</mo><mn>0</mn></math></span> is equal to the D-to-N map <span><math><mover><mrow><mi>Λ</mi></mrow><mrow><mo>ˆ</mo></mrow></mover><mo>(</mo><mi>ν</mi><mo>)</mo></math></span> on the interior of the disk associated with the potential <span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>ν</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>y</mi><mo>)</mo></math></span>. Secondly, we study the ground state energy of the D-to-N map <span><math><mover><mrow><mi>Λ</mi></mrow><mrow><mo>ˇ</mo></mrow></mover><mo>(</mo><mi>b</mi><mo>,</mo><mi>ν</mi><mo>)</mo></math></span> and show that the strong diamagnetism property holds. Finally we slightly extend to the exterior case the asymptotic results as <span><math><mi>b</mi><mo>→</mo><mo>∞</mo></math></span> obtained in the interior case for general domains.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"205 ","pages":"Article 103799"},"PeriodicalIF":2.3,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145219206","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}
Pub Date : 2025-09-12DOI: 10.1016/j.matpur.2025.103792
Deqin Zhou , Felipe Linares
<div><div>We consider the long time behavior of the solutions of the coupled Schrödinger-KdV system<span><span><span><math><mrow><mo>{</mo><mtable><mtr><mtd><mi>i</mi><msub><mrow><mo>∂</mo></mrow><mrow><mi>t</mi></mrow></msub><mi>u</mi><mo>+</mo><msubsup><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow><mrow><mn>2</mn></mrow></msubsup><mi>u</mi><mo>=</mo><mi>α</mi><mi>u</mi><mi>v</mi><mo>+</mo><mi>β</mi><mi>u</mi><mo>|</mo><mi>u</mi><msup><mrow><mo>|</mo></mrow><mrow><mn>2</mn></mrow></msup><mo>,</mo><mspace></mspace><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo><mo>∈</mo><mi>R</mi><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>,</mo></mtd></mtr><mtr><mtd><msub><mrow><mo>∂</mo></mrow><mrow><mi>t</mi></mrow></msub><mi>v</mi><mo>+</mo><msubsup><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow><mrow><mn>3</mn></mrow></msubsup><mi>v</mi><mo>+</mo><mi>v</mi><msub><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow></msub><mi>v</mi><mo>=</mo><mi>γ</mi><msub><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow></msub><mo>(</mo><mo>|</mo><mi>u</mi><msup><mrow><mo>|</mo></mrow><mrow><mn>2</mn></mrow></msup><mo>)</mo><mo>,</mo><mspace></mspace><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo><mo>∈</mo><mi>R</mi><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>,</mo></mtd></mtr><mtr><mtd><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo><msub><mrow><mo>|</mo></mrow><mrow><mi>t</mi><mo>=</mo><mn>0</mn></mrow></msub><mo>=</mo><mo>(</mo><msub><mrow><mi>u</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>,</mo><msub><mrow><mi>v</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>)</mo><mo>.</mo></mtd></mtr></mtable></mrow></math></span></span></span> We show that global solutions to this system satisfy locally energy decay in a suitable interval, growing unbounded in time, in two situations. In the first case, we regard the parameter vector <span><math><mo>(</mo><mi>α</mi><mo>,</mo><mi>β</mi><mo>,</mo><mi>γ</mi><mo>)</mo><mo>∈</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>×</mo><mover><mrow><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></mrow><mo>‾</mo></mover><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span> without any size assumption on the initial data in <span><math><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup><mo>(</mo><mi>R</mi><mo>)</mo><mo>×</mo><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup><mo>(</mo><mi>R</mi><mo>)</mo></math></span>. In the second one, we consider the parameter vector <span><math><mo>(</mo><mi>α</mi><mo>,</mo><mi>β</mi><mo>,</mo><mi>γ</mi><mo>)</mo><mo>∈</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>−</mo></mrow></msup><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span>. In this case, we give a ‘‘smallness” criterion involving the product of the parameter −<em>β</em> and a constant depending on the initial data in <span><
我们考虑耦合Schrödinger-KdV系统{i∂tu+∂x2u=αuv+βu|u|2,(x,t)∈R×R+,∂tv+∂x3v+v∂xv=γ∂x(|u|2),(x,t)∈R×R+,(u,v)|t=0=(u0,v0)的长时间行为。在两种情况下,我们证明了该系统的全局解在一个适当的区间内满足局部能量衰减,并随时间无界增长。在第一种情况下,我们考虑参数向量(α,β,γ)∈R+×R+,对H1(R)×H1(R)中的初始数据没有任何大小假设。在第二个例子中,我们考虑参数向量(α,β,γ)∈R+×R−×R+。在这种情况下,我们给出了一个“小”准则,涉及参数- β和一个常数的乘积,这取决于H1(R)×H1(R)中的初始数据。我们的研究结果积极地回答了F. Linares, A. J. Mendez (2021) b[18]中提出的开放性问题。我们使用了与前一篇文章不同的新思路和技术。
{"title":"On long time behavior of solutions of the Schrödinger-KdV system with and without resonant interactions","authors":"Deqin Zhou , Felipe Linares","doi":"10.1016/j.matpur.2025.103792","DOIUrl":"10.1016/j.matpur.2025.103792","url":null,"abstract":"<div><div>We consider the long time behavior of the solutions of the coupled Schrödinger-KdV system<span><span><span><math><mrow><mo>{</mo><mtable><mtr><mtd><mi>i</mi><msub><mrow><mo>∂</mo></mrow><mrow><mi>t</mi></mrow></msub><mi>u</mi><mo>+</mo><msubsup><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow><mrow><mn>2</mn></mrow></msubsup><mi>u</mi><mo>=</mo><mi>α</mi><mi>u</mi><mi>v</mi><mo>+</mo><mi>β</mi><mi>u</mi><mo>|</mo><mi>u</mi><msup><mrow><mo>|</mo></mrow><mrow><mn>2</mn></mrow></msup><mo>,</mo><mspace></mspace><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo><mo>∈</mo><mi>R</mi><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>,</mo></mtd></mtr><mtr><mtd><msub><mrow><mo>∂</mo></mrow><mrow><mi>t</mi></mrow></msub><mi>v</mi><mo>+</mo><msubsup><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow><mrow><mn>3</mn></mrow></msubsup><mi>v</mi><mo>+</mo><mi>v</mi><msub><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow></msub><mi>v</mi><mo>=</mo><mi>γ</mi><msub><mrow><mo>∂</mo></mrow><mrow><mi>x</mi></mrow></msub><mo>(</mo><mo>|</mo><mi>u</mi><msup><mrow><mo>|</mo></mrow><mrow><mn>2</mn></mrow></msup><mo>)</mo><mo>,</mo><mspace></mspace><mo>(</mo><mi>x</mi><mo>,</mo><mi>t</mi><mo>)</mo><mo>∈</mo><mi>R</mi><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>,</mo></mtd></mtr><mtr><mtd><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo><msub><mrow><mo>|</mo></mrow><mrow><mi>t</mi><mo>=</mo><mn>0</mn></mrow></msub><mo>=</mo><mo>(</mo><msub><mrow><mi>u</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>,</mo><msub><mrow><mi>v</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>)</mo><mo>.</mo></mtd></mtr></mtable></mrow></math></span></span></span> We show that global solutions to this system satisfy locally energy decay in a suitable interval, growing unbounded in time, in two situations. In the first case, we regard the parameter vector <span><math><mo>(</mo><mi>α</mi><mo>,</mo><mi>β</mi><mo>,</mo><mi>γ</mi><mo>)</mo><mo>∈</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>×</mo><mover><mrow><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></mrow><mo>‾</mo></mover><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span> without any size assumption on the initial data in <span><math><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup><mo>(</mo><mi>R</mi><mo>)</mo><mo>×</mo><msup><mrow><mi>H</mi></mrow><mrow><mn>1</mn></mrow></msup><mo>(</mo><mi>R</mi><mo>)</mo></math></span>. In the second one, we consider the parameter vector <span><math><mo>(</mo><mi>α</mi><mo>,</mo><mi>β</mi><mo>,</mo><mi>γ</mi><mo>)</mo><mo>∈</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>−</mo></mrow></msup><mo>×</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span>. In this case, we give a ‘‘smallness” criterion involving the product of the parameter −<em>β</em> and a constant depending on the initial data in <span><","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"205 ","pages":"Article 103792"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094983","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}
Pub Date : 2025-09-12DOI: 10.1016/j.matpur.2025.103794
Baohua Fu , Jie Liu
The algebra of symmetric tensors of a projective manifold X leads to a natural dominant affinization morphism It is shown that is birational if and only if is big. We prove that if is birational, then is a symplectic variety endowed with the Schouten–Nijenhuis bracket if and only if is of Fano type, which is the case for smooth projective toric varieties, smooth horospherical varieties with small boundary, and the quintic del Pezzo threefold. These give examples of a distinguished class of conical symplectic varieties, which we call symplectic orbifold cones.
对对称张量S(X)的代数,其中对投影流形X的H0(X,S•TX)是一个自然优势仿射态φX:T X ZX是一个自然优势仿射态。证明了φX当且仅当TX较大时是两位数的。证明了φX是双分型的,则当且仅当PTX为Fano型时,ZX是赋有Schouten-Nijenhuis括弧的简型变种,对于光滑投影环型变种、小边界光滑全球型变种和五次del Pezzo三重型都是如此。这些给出了一类特殊的圆锥辛变异体的例子,我们称之为辛轨道锥。
{"title":"Symplectic singularities arising from algebras of symmetric tensors","authors":"Baohua Fu , Jie Liu","doi":"10.1016/j.matpur.2025.103794","DOIUrl":"10.1016/j.matpur.2025.103794","url":null,"abstract":"<div><div>The algebra of symmetric tensors <span><math><mi>S</mi><mo>(</mo><mi>X</mi><mo>)</mo><mo>≔</mo><msup><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msup><mo>(</mo><mi>X</mi><mo>,</mo><msup><mrow><mi>S</mi></mrow><mrow><mo>•</mo></mrow></msup><msub><mrow><mi>T</mi></mrow><mrow><mi>X</mi></mrow></msub><mo>)</mo></math></span> of a projective manifold <em>X</em> leads to a natural dominant affinization morphism<span><span><span><math><msub><mrow><mi>φ</mi></mrow><mrow><mi>X</mi></mrow></msub><mo>:</mo><msup><mrow><mi>T</mi></mrow><mrow><mo>⁎</mo></mrow></msup><mi>X</mi><mo>⟶</mo><msub><mrow><mi>Z</mi></mrow><mrow><mi>X</mi></mrow></msub><mo>≔</mo><mi>Spec</mi><mspace></mspace><mi>S</mi><mo>(</mo><mi>X</mi><mo>)</mo><mo>.</mo></math></span></span></span> It is shown that <span><math><msub><mrow><mi>φ</mi></mrow><mrow><mi>X</mi></mrow></msub></math></span> is birational if and only if <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>X</mi></mrow></msub></math></span> is big. We prove that if <span><math><msub><mrow><mi>φ</mi></mrow><mrow><mi>X</mi></mrow></msub></math></span> is birational, then <span><math><msub><mrow><mi>Z</mi></mrow><mrow><mi>X</mi></mrow></msub></math></span> is a symplectic variety endowed with the Schouten–Nijenhuis bracket if and only if <span><math><mi>P</mi><msub><mrow><mi>T</mi></mrow><mrow><mi>X</mi></mrow></msub></math></span> is of Fano type, which is the case for smooth projective toric varieties, smooth horospherical varieties with small boundary, and the quintic del Pezzo threefold. These give examples of a distinguished class of conical symplectic varieties, which we call symplectic orbifold cones.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"204 ","pages":"Article 103794"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109260","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}
Pub Date : 2025-09-12DOI: 10.1016/j.matpur.2025.103793
Massimiliano Mella
Two projective varieties are said to be Cremona equivalent if there is a Cremona modification sending one onto the other. In the last decade, Cremona equivalence has been investigated widely, and we now have a complete theory for non-divisorial reduced schemes. The case of irreducible divisors is completely different, and not much is known besides the case of plane curves and a few classes of surfaces. In particular, for plane curves it is a classical result that an irreducible plane curve is Cremona equivalent to a line if and only if its log-Kodaira dimension is negative. This can be interpreted as the log version of Castelnuovo's rationality criterion for surfaces. One expects that a similar result for surfaces in projective space should not be true, as it is false, the generalization in higher dimensions of Castelnuovo's Rationality Theorem. In this paper, the first example of such behavior is provided, exhibiting a rational surface in the projective space with negative log-Kodaira dimension, which is not Cremona equivalent to a plane. This can be thought of as a sort of log Iskovkikh-Manin, Clemens-Griffith, Artin-Mumford example. Using this example, it is then possible to show that Cremona equivalence to a plane is neither open nor closed among log pairs with negative Kodaira dimension.
{"title":"Cremona equivalence and log Kodaira dimension","authors":"Massimiliano Mella","doi":"10.1016/j.matpur.2025.103793","DOIUrl":"10.1016/j.matpur.2025.103793","url":null,"abstract":"<div><div>Two projective varieties are said to be Cremona equivalent if there is a Cremona modification sending one onto the other. In the last decade, Cremona equivalence has been investigated widely, and we now have a complete theory for non-divisorial reduced schemes. The case of irreducible divisors is completely different, and not much is known besides the case of plane curves and a few classes of surfaces. In particular, for plane curves it is a classical result that an irreducible plane curve is Cremona equivalent to a line if and only if its log-Kodaira dimension is negative. This can be interpreted as the log version of Castelnuovo's rationality criterion for surfaces. One expects that a similar result for surfaces in projective space should not be true, as it is false, the generalization in higher dimensions of Castelnuovo's Rationality Theorem. In this paper, the first example of such behavior is provided, exhibiting a rational surface in the projective space with negative log-Kodaira dimension, which is not Cremona equivalent to a plane. This can be thought of as a sort of log Iskovkikh-Manin, Clemens-Griffith, Artin-Mumford example. Using this example, it is then possible to show that Cremona equivalence to a plane is neither open nor closed among log pairs with negative Kodaira dimension.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"204 ","pages":"Article 103793"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145104686","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}
Pub Date : 2025-09-12DOI: 10.1016/j.matpur.2025.103798
Christopher Henderson , King-Yeung Lam
We consider the road-field reaction-diffusion model introduced by Berestycki, Roquejoffre, and Rossi. By performing a “thin-front” limit, we are able to deduce a Hamilton-Jacobi equation with a suitable effective Hamiltonian on the road that governs the front location of the road-field model. Our main motivation is to apply the theory of strong (flux-limited) viscosity solutions in order to determine a control formulation interpretation of the front location. In view of the ecological meaning of the road-field model, this is natural as it casts the invasion problem as one of finding optimal paths that balance the positive growth rate in the field with the fast diffusion on the road.
Our main contribution is a nearly complete picture of the behavior on two-road conical domains. When the diffusivities on each road are the same, we show that the propagation speed in each direction in the cone can be computed via those associated with one-road half-space problem. When the diffusivities differ, we show that the speed along the faster road is unchanged, while the speed along the slower road can be enhanced. Along the way we provide a new proof of known results on the one-road half-space problem via our approach.
{"title":"A Hamilton-Jacobi approach to road-field reaction-diffusion models","authors":"Christopher Henderson , King-Yeung Lam","doi":"10.1016/j.matpur.2025.103798","DOIUrl":"10.1016/j.matpur.2025.103798","url":null,"abstract":"<div><div>We consider the road-field reaction-diffusion model introduced by Berestycki, Roquejoffre, and Rossi. By performing a “thin-front” limit, we are able to deduce a Hamilton-Jacobi equation with a suitable effective Hamiltonian on the road that governs the front location of the road-field model. Our main motivation is to apply the theory of strong (flux-limited) viscosity solutions in order to determine a control formulation interpretation of the front location. In view of the ecological meaning of the road-field model, this is natural as it casts the invasion problem as one of finding optimal paths that balance the positive growth rate in the field with the fast diffusion on the road.</div><div>Our main contribution is a nearly complete picture of the behavior on two-road conical domains. When the diffusivities on each road are the same, we show that the propagation speed in each direction in the cone can be computed via those associated with one-road half-space problem. When the diffusivities differ, we show that the speed along the faster road is unchanged, while the speed along the slower road can be enhanced. Along the way we provide a new proof of known results on the one-road half-space problem via our approach.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"205 ","pages":"Article 103798"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145117576","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}
Pub Date : 2025-09-12DOI: 10.1016/j.matpur.2025.103795
Youshan Tao , Michael Winkler
In a smoothly bounded domain , , and with and , this manuscript considers the Neumann initial-boundary problem for the Keller-Segel type system which arises in the modeling for chemotactic movement in the presence of certain anisotropic signal production mechanisms.
Unlike the classical Keller-Segel model whose solutions may blow up in finite time in high-dimensional domains, this problem is shown to admit a unique global bounded classical solution whenever the difference is appropriately small. This markedly distinguishes (⋆) from classical Keller-Segel systems for which some solutions are known to blow up in finite time when .
在光滑有界域Ω∧Rn, n≤5,并且D>;0和D>;0中,本文考虑了Keller-Segel型系统{ut=DΔu−∇⋅(u∇v),vt=dΔv+∇⋅(u∇v)−v+u,(-)的Neumann初始边界问题,该问题出现在存在某些各向异性信号产生机制的趋化运动建模中。与经典Keller-Segel模型的解在高维域中可能在有限时间内爆炸不同,当差分|D - D |适当小时,该问题承认一个唯一的全局有界经典解。这明显区别于经典的Keller-Segel系统,对于经典的Keller-Segel系统,已知当n≥2时,某些解会在有限时间内爆炸。
{"title":"Suppression of blow-up by local anisotropy of signal production in the Keller-Segel system","authors":"Youshan Tao , Michael Winkler","doi":"10.1016/j.matpur.2025.103795","DOIUrl":"10.1016/j.matpur.2025.103795","url":null,"abstract":"<div><div>In a smoothly bounded domain <span><math><mi>Ω</mi><mo>⊂</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>n</mi></mrow></msup></math></span>, <span><math><mi>n</mi><mo>≤</mo><mn>5</mn></math></span>, and with <span><math><mi>D</mi><mo>></mo><mn>0</mn></math></span> and <span><math><mi>d</mi><mo>></mo><mn>0</mn></math></span>, this manuscript considers the Neumann initial-boundary problem for the Keller-Segel type system<span><span><span><math><mrow><mrow><mo>{</mo><mtable><mtr><mtd><msub><mrow><mi>u</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mi>D</mi><mi>Δ</mi><mi>u</mi><mo>−</mo><mi>∇</mi><mo>⋅</mo><mo>(</mo><mi>u</mi><mi>∇</mi><mi>v</mi><mo>)</mo><mo>,</mo></mtd></mtr><mtr><mtd><msub><mrow><mi>v</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mi>d</mi><mi>Δ</mi><mi>v</mi><mo>+</mo><mi>∇</mi><mo>⋅</mo><mo>(</mo><mi>u</mi><mi>∇</mi><mi>v</mi><mo>)</mo><mo>−</mo><mi>v</mi><mo>+</mo><mi>u</mi><mo>,</mo></mtd></mtr></mtable></mrow><mspace></mspace><mo>(</mo><mo>⋆</mo><mo>)</mo></mrow></math></span></span></span> which arises in the modeling for chemotactic movement in the presence of certain anisotropic signal production mechanisms.</div><div>Unlike the classical Keller-Segel model whose solutions may blow up in finite time in high-dimensional domains, this problem is shown to admit a unique global bounded classical solution whenever the difference <span><math><mo>|</mo><mi>D</mi><mo>−</mo><mi>d</mi><mo>|</mo></math></span> is appropriately small. This markedly distinguishes (⋆) from classical Keller-Segel systems for which some solutions are known to blow up in finite time when <span><math><mi>n</mi><mo>≥</mo><mn>2</mn></math></span>.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"205 ","pages":"Article 103795"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094981","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}
Pub Date : 2025-09-12DOI: 10.1016/j.matpur.2025.103796
Simon Becker , Angeliki Menegaki , Jiming Yu
We consider chains of N harmonic oscillators in two dimensions coupled to a Langevin heat reservoir at fixed temperature, a classical model for heat conduction introduced by Lebowitz, Lieb, and Rieder (1967). We extend our previous results (Becker and Menegaki, 2021) significantly by providing a full spectral description of the full Fokker-Planck operator, also allowing for the presence of a constant external magnetic field for charged oscillators. We then study oscillator chains with additional next-to-nearest-neighbor interactions and find that the spectral gap undergoes a phase transition if the next-to-nearest-neighbor interactions are sufficiently strong and may even cease to exist for oscillator chains of finite length.
{"title":"Spectral analysis and phase transitions for long-range interactions in harmonic chains of oscillators","authors":"Simon Becker , Angeliki Menegaki , Jiming Yu","doi":"10.1016/j.matpur.2025.103796","DOIUrl":"10.1016/j.matpur.2025.103796","url":null,"abstract":"<div><div>We consider chains of <em>N</em> harmonic oscillators in two dimensions coupled to a Langevin heat reservoir at fixed temperature, a classical model for heat conduction introduced by Lebowitz, Lieb, and Rieder (1967). We extend our previous results (Becker and Menegaki, 2021) significantly by providing a full spectral description of the full Fokker-Planck operator, also allowing for the presence of a constant external magnetic field for charged oscillators. We then study oscillator chains with additional next-to-nearest-neighbor interactions and find that the spectral gap undergoes a phase transition if the next-to-nearest-neighbor interactions are sufficiently strong and may even cease to exist for oscillator chains of finite length.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"204 ","pages":"Article 103796"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109259","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}
Pub Date : 2025-09-12DOI: 10.1016/j.matpur.2025.103797
Fabian Rupp , Christian Scharrer
We provide sharp sufficient criteria for an integral 2-varifold to be induced by a -conformal immersion of a smooth surface. Our approach is based on a fine analysis of the Hausdorff density for 2-varifolds with critical integrability of the mean curvature and a recent local regularity result by Bi–Zhou. In codimension one, there are only three possible density values below 2, each of which can be attained with equality in the Li–Yau inequality for the Willmore functional by the unit sphere, the double bubble, and the triple bubble. We show that below an optimal threshold for the Willmore energy, a varifold induced by a current without boundary is in fact a curvature varifold with a uniform bound on its second fundamental form. Consequently, the minimization of the Willmore functional in the class of curvature varifolds with prescribed even Euler characteristic provides smooth solutions for the Willmore problem. In particular, the “ambient” varifold approach and the “parametric” approach are equivalent for minimizing the Willmore energy.
{"title":"Global regularity of integral 2-varifolds with square integrable mean curvature","authors":"Fabian Rupp , Christian Scharrer","doi":"10.1016/j.matpur.2025.103797","DOIUrl":"10.1016/j.matpur.2025.103797","url":null,"abstract":"<div><div>We provide sharp sufficient criteria for an integral 2-varifold to be induced by a <span><math><msup><mrow><mi>W</mi></mrow><mrow><mn>2</mn><mo>,</mo><mn>2</mn></mrow></msup></math></span>-conformal immersion of a smooth surface. Our approach is based on a fine analysis of the Hausdorff density for 2-varifolds with critical integrability of the mean curvature and a recent local regularity result by Bi–Zhou. In codimension one, there are only three possible density values below 2, each of which can be attained with equality in the Li–Yau inequality for the Willmore functional by the unit sphere, the double bubble, and the triple bubble. We show that below an optimal threshold for the Willmore energy, a varifold induced by a current without boundary is in fact a curvature varifold with a uniform bound on its second fundamental form. Consequently, the minimization of the Willmore functional in the class of curvature varifolds with prescribed even Euler characteristic provides smooth solutions for the Willmore problem. In particular, the “ambient” varifold approach and the “parametric” approach are equivalent for minimizing the Willmore energy.</div></div>","PeriodicalId":51071,"journal":{"name":"Journal de Mathematiques Pures et Appliquees","volume":"204 ","pages":"Article 103797"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109261","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}