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2109.05299 2026-06-08 math.AP 版本更新

Global Existence for the unstable Cahn-Hilliard equation in 2D with a Shear Flow

二维不稳定的Cahn-Hilliard方程在剪切流中的全局存在性

Bingyang Hu, Dinghua Xu, Yeyu Zhang

AI总结 本文研究了在二维剪切流下不稳定的Cahn-Hilliard方程的全局存在性,通过分析剪切项和非线性化学势的作用,证明了在特定条件下L²能量指数衰减至零。

Comments 31 pages. Comments are welcome!

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AI中文摘要

本文研究了在二维剪切流下不稳定的Cahn-Hilliard方程:$$\begin{cases} u_t+Av_1(y) \partial_x u+\varepsilon Δ^2 u= Δ(a u^3+ b u^2) \quad & \quad \text{在} \quad \mathbb T^2 \text{上}; \\ \\ u \ \text{周期性} \quad & \quad \text{在} \quad \partial \mathbb T^2 \text{上}, \end{cases}$$其中$u_0\in H_0^2(\mathbb T^2)$,$A,\varepsilon>0$,$a<0$,$b\in\mathbb R$。条件$a<0$将模型置于不稳定的相场 regime:非线性化学势可能放大而非恢复浓度波动,如同相分离。剪切项$Av_1(y)\partial_xu$模拟沿剪切方向的强制搅拌;通过混合,它增强耗散并抵消由不稳定三次项$Δ(au^3)$驱动的增长。假设剪切剖面有有限多个临界点且线性增长模式仅出现在剪切方向,证明在$|a|$和$\|\int_{\mathbb T} u_0(x,\cdot)\,dx\|_{L_y^2}$足够小时,$L^2$能量指数衰减至零。

英文摘要

In this paper, we study the advective unstable Cahn--Hilliard equation on $\mathbb T^2$ with shear flow: \begin{equation*} \begin{cases} u_t+Av_1(y) \partial_x u+\varepsilon Δ^2 u= Δ(a u^3+ b u^2) \quad & \quad \textrm{on} \quad \mathbb T^2; \\ \\ u \ \textrm{periodic} \quad & \quad \textrm{on} \quad \partial \mathbb T^2, \end{cases} \end{equation*} where $u_0\in H_0^2(\mathbb T^2)$, $A,\varepsilon>0$, $a<0$, and $b\in\mathbb R$. The condition $a<0$ puts the model in an unstable phase-field regime: the nonlinear chemical potential may amplify, rather than restore, concentration fluctuations, as in spinodal decomposition. The shear term $Av_1(y)\partial_xu$ models imposed stirring along the shear direction; through mixing, it enhances dissipation and counteracts the growth driven by the unstable cubic term $Δ(au^3)$. Assuming that the shear profile has finitely many critical points and that linearly growing modes occur only in the shear direction, we prove that the $L^2$-energy converges exponentially to zero, provided $|a|$ and $\|\int_{\mathbb T} u_0(x,\cdot)\,dx\|_{L_y^2}$ are sufficiently small.

2601.20820 2026-06-08 hep-th 版本更新

Gravitationally Induced UV Completion of an $O(N)$ Scalar Theory

引力诱导的O(N)标量理论的紫外完成

Alfio M. Bonanno, Emiliano M. Glaviano

AI总结 研究O(N)标量场理论在引力非最小耦合下的紫外完成,通过Wilsonian功能重整化群分析,发现两种固定点解,其中一种具有消失的四次耦合和有限的引力耦合,使理论渐进安全且具有平坦标量势。

Comments 64 pages, 18 figures

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Journal ref
Annals of Physics, Volume 492, September 2026, 170545
AI中文摘要

我们研究了非最小耦合引力的O(N)标量场理论的紫外完成,使用Wilsonian功能重整化群在proper-time形式中进行。聚焦于自发破缺相,研究标量势和非最小曲率耦合在运行最小值附近的RG流。我们识别出两种不同的固定点解,其中一种是紫外吸引的,其特征是四次耦合消失并伴有有限的相互作用引力耦合。对于有限的红外初始条件区域,RG轨迹在所有尺度上保持规则并接近该固定点。这种机制使理论渐进安全,并导致紫外处的平坦标量势。我们展示这种机制在改变截断方案和截断时是稳健的,允许紫外完成要求约束破缺相中标量耦合的红外值和质量标度。

英文摘要

We investigate the ultraviolet completion of an $O(N)$ scalar field theory non-minimally coupled to gravity using the Wilsonian functional renormalization group in the proper-time formulation. Focusing on the spontaneously broken phase, we study the RG flow of the scalar potential and the non-minimal curvature coupling expanded around a running minimum. We identify two distinct classes of fixed-point solutions, one of which is ultraviolet attractive and characterized by a vanishing quartic coupling together with finite, interacting gravitational couplings. For a finite region of infrared initial conditions, the RG trajectories remain regular at all scales and approach this fixed point. This mechanism renders the theory asymptotically safe and leads to a flat scalar potential in the ultraviolet. We show that this mechanism is robust under changes of cutoff scheme and truncation, allowing the ultraviolet completion requirement to constrain the infrared values of the scalar couplings and the mass scale in the broken phase.

2601.19858 2026-06-08 gr-qc 版本更新

Melvin--Bonnor and Bertotti--Robinson spacetimes with Baryonic charge

具有重子电荷的Melvin-Bonnor和Bertotti-Robinson时空

José Barrientos, Fabrizio Canfora, Adolfo Cisterna, Keanu Müller, Anibal Neira

AI总结 本文通过将Einstein-标量-Maxwell理论解与gauged Skyrme-Maxwell-Einstein模型解映射,推导出关联时空质量参数、重子电荷和外部磁场的新质量公式,揭示质量与重子电荷的非独立关系。

Comments V2 with minor improvements. Accepted for publication in The European Physical Journal C

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AI中文摘要

在本工作中,我们利用一个字典,将Einstein-标量-Maxwell理论的解映射到(3+1)维gauged Skyrme-Maxwell-Einstein模型的解中,使得在外部电磁背景下存在的引力标量场配置可以解释为重子量。使用重子电荷作为拓扑密度积分的定义,我们推导出新的质量公式,将时空质量参数与重子电荷、外部磁场和其他解参数相关联。结果表明,质量与重子电荷并非独立。这些闭合的解析表达式编码了难以从已知解中提取的物理信息。特别是对于本文考虑的解类,大质量时质量与重子电荷的关系是线性的,而在中间值时出现显著的非线性偏差。该框架为从已知解中提取新的物理见解以及利用Einstein-标量-Maxwell理论可用的解生成技术构造新的重子配置提供了有用的工具。

英文摘要

In this work, we exploit a dictionary that maps solutions of the Einstein--Scalar--Maxwell theory to those of gauged Skyrme--Maxwell--Einstein models in $(3+1)$ dimensions, allowing gravitating scalar-field configurations in external electromagnetic backgrounds to be interpreted in terms of baryonic quantities. Using the definition of Baryonic charge as the integral of a topological density, we derive novel mass formulas that relate the spacetime mass parameter to the Baryonic charge, the external magnetic field, and other solution parameters. As a result, the mass and Baryonic charge are not independent. These closed analytic expressions encode physical information that would otherwise be difficult to extract. In particular, for the class of solutions considered here, the relation between mass and Baryonic charge is linear at large mass, while significant nonlinear deviations appear at intermediate values. This framework provides a useful tool for both extracting new physical insights from known solutions and constructing new baryonic configurations using the solution-generating techniques available for Einstein--Scalar--Maxwell theory.

2601.19542 2026-06-08 math.NA cs.NA physics.comp-ph 版本更新

Unified Regularization of 2D Singular Integrals for Axisymmetric Galerkin BEM in Eddy-Current Evaluation

二维奇异积分的统一正则化用于轴对称伽辽金BEM在涡流评估中

Yao Luo

AI总结 本文提出了一种轴对称伽辽金边界元方法用于建模激励线圈与导体物体之间的涡流相互作用,通过统一的正则化框架处理二维奇异积分,提高了计算效率和稳定性。

Comments 30 pages, 6 figures

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AI中文摘要

本文提出了一种轴对称伽辽金边界元方法(BEM)用于建模涡流相互作用。该方法基于Stratton-Chu表示式推导边界积分方程,处理空气和导电区域中的矢量电势的方位分量。核心贡献是为伽辽金BEM中的二维奇异积分提出统一的正则化框架,通过一组共同的积分变换处理对数和Cauchy奇异性和,消除了逐个情况分析奇异性的需要,实现了直接的数值积分。正则化和积分稳定性被证明并数值验证。该方法在多个典型轴对称几何体上得到验证,包括圆柱、圆锥和球壳。数值实验显示在测试频率区间和线圈抬升距离内具有高精度和计算效率。结果表明,所提出的轴对称伽辽金BEM结合积分变换技术,为轴对称涡流无损评估提供了一个稳健且高效的框架。

英文摘要

This paper presents an axisymmetric Galerkin boundary element method (BEM) for modeling eddy-current interactions between excitation coils and conductive objects. The formulation derives boundary integral equations from the Stratton-Chu representation for the azimuthal component of the vector potential in both air and conductive regions. The central contribution is a unified regularization framework for the two-dimensional (2D) singular integrals arising in Galerkin BEM. This framework handles both logarithmic and Cauchy singularities through a common set of integral transformations, eliminating the need for case-by-case analytical singularity extraction and enabling straightforward numerical quadrature. The regularization and quadrature stability are proved and verified numerically. The method is validated on several representative axisymmetric geometries, including cylindrical, conical, and spherical shells. Numerical experiments demonstrate consistently high accuracy and computational efficiency over the tested frequency interval and coil lift-off distances. The results confirm that the proposed axisymmetric Galerkin BEM, combined with the integral transformation technique, provides a robust and efficient framework for axisymmetric eddy-current nondestructive evaluation.

2601.17452 2026-06-08 math.NA cs.NA 版本更新

Numerical Study of Dissipative Weak Solutions for the Euler Equations of Gas Dynamics

关于气体动力学欧拉方程耗散弱解的数值研究

Shaoshuai Chu, Michael Herty, Alexander Kurganov, Maria Lukacova-Medvidova, Changsheng Yu

AI总结 本文采用多种高阶方法研究气体动力学欧拉方程的耗散弱解,通过数值实验验证了不同方法在空间和时间收敛性下的弱解特性及耗散弱解的计算方法。

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AI中文摘要

本文采用多种高阶方法研究气体动力学欧拉方程的耗散弱解,通过数值实验验证了不同方法在空间和时间收敛性下的弱解特性及耗散弱解的计算方法。

英文摘要

We study dissipative weak (DW) solutions of the Euler equations of gas dynamics using the first-, second-, third-, fifth-, seventh-, and ninth-order local characteristic decomposition-based central-upwind (LCDCU), low-dissipation central-upwind (LDCU), and viscous finite volume (VFV) methods, whose higher-order extensions are obtained via the framework of the alternative weighted essentially non-oscillatory (A-WENO) schemes. These methods are applied to several benchmark problems, including several two-dimensional Riemann problems and a Kelvin-Helmholtz instability test. The numerical results demonstrate that for methods converging only weakly in space and time, the limiting solutions are generalized DW solutions, approximated in the sense of ${\cal K}$-convergence and dependent on the numerical scheme. For all of the studied methods, we compute the associated Young measures and compare the DW solutions using entropy production and energy defect criteria.

2601.18004 2026-06-08 cs.FL cs.DM 版本更新

Persistent Permutability in Choice Petri Nets

选择Petri网中的持久可交换性

Eike Best, Raymond Devillers

AI总结 研究了选择Petri网中的持久可交换性,证明了某些类别的Petri网中持久可交换性可推导出整体持久性。

Comments 36 pages, 22 figures

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AI中文摘要

研究了选择Petri网中的持久可交换性,证明了某些类别的Petri网中持久可交换性可推导出整体持久性。

英文摘要

Persistence is a strong, global, behavioural property of a Petri net, meaning that no activity can disable a different activity. Persistent permutability is a weaker property, pertaining to individual interleavings of a Petri net and stating that a non-persistent sequence can be permuted into a persistent one. We identify Petri net classes for which persistent permutability already suffices to imply overall persistence. These classes generalise free-choice nets and are related to Petri's concept of ``confusion'', while they are distinguished from each other by diverse restrictions on the choice structure of a net. We prove Ochmanski's conjecture to be correct for these classes.

2601.17612 2026-06-08 stat.ME 版本更新

A Regularised Latent-Class Item Response Model for Detecting Measurement Non-Invariance in Ordinal Response Scales

用于检测有序反应量表中测量非不变性的正则化潜在类别项目反应模型

Gabriel Wallin, Qi Huang

AI总结 提出一种正则化潜在类别项目反应模型,通过ℓ1惩罚边际似然和EM算法检测有序量表上的差异项目功能,无需已知分组标签或锚定项目。

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AI中文摘要

当量表的心理测量属性在不同子组间存在差异时,会出现测量非不变性,从而削弱组间比较的有效性。在项目层面,这表现为差异项目功能(DIF),即在控制潜在特质后,项目反应在不同组间存在差异。本文开发了一个框架,用于检测有序量表中的DIF,无需已知组标签或锚定项目。我们构建了一个比例优势潜在类别项目反应模型,其中个体被概率性地分配到潜在类别。DIF通过类别特定的截距和斜率变化来捕捉,允许均匀和非均匀DIF。通过在稀疏性假设下使用ℓ1惩罚边际似然实现识别,并使用定制的EM算法进行估计。由于类别特定斜率使每个潜在类别的位置和尺度均无法识别,稀疏性在锚定潜在度量的同时选择DIF效应。模拟研究显示,项目参数及两种类型的DIF均能准确恢复。对一项人格测试的实证应用揭示了具有不同反应模式的潜在子组,并识别出显示潜在类别特定测量非不变性的项目。该框架为在比较组未观测或定义不明确时评估有序量表的测量不变性提供了一种灵活的方法。

英文摘要

Measurement non-invariance arises when the psychometric properties of a scale differ across subgroups, undermining the validity of group comparisons. At the item level, this manifests as differential item functioning (DIF), where item responses differ across groups after controlling for the latent trait. This paper develops a framework for detecting DIF in ordinal scales without requiring known group labels or anchor items. We formulate a proportional-odds latent-class item response model in which individuals are assigned probabilistically to latent classes. DIF is captured through class-specific intercept and slope shifts, allowing both uniform and non-uniform DIF. Identification is achieved through an \(\ell_1\)-penalised marginal likelihood under a sparsity assumption, with estimation implemented using a tailored EM algorithm. Because class-specific slopes leave both the location and scale of each latent class unidentified, sparsity anchors the latent metric while selecting DIF effects. Simulation studies demonstrate accurate recovery of item parameters and both types of DIF. An empirical application to a personality test reveals latent subgroups with distinct response patterns and identifies items displaying potential class-specific measurement non-invariance. The framework provides a flexible approach for assessing measurement invariance in ordinal scales when comparison groups are unobserved or poorly defined.

2601.17182 2026-06-08 math.NT 版本更新

Arithmetic Information of Rational Elliptic Surfaces, and Shioda's Rank 68 Elliptic Surface

有理椭圆面的算术信息,以及Shioda的秩68椭圆面

Blair Butler, Andreas-Stephan Elsenhans

AI总结 本文提出一种算法,用于确定有理椭圆面的算术信息,包括定义域。作为应用,展示了Shioda的秩68椭圆面的定义域为次数829440的数域。

Comments 15 pages, to be presented at ANTS26. Changes made following reviewer feedback

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AI中文摘要

椭圆面$E \rightarrow \mathbb{P}^1$的Mordell-Weil群的定义域是使得其所有$\Bar{\mathbb{Q}}(t)$-有理点都在$k(t)$上的最小数域$k$。本文提出了一种在\Magma中实现的算法,可用于确定任何有理椭圆面的算术信息,包括定义域。作为应用,本文展示了Shioda的秩68椭圆面$y^2 = x^3 + t^{360} + 1$的定义域是一个次数829440的数域。

英文摘要

The field of definition of the Mordell-Weil group of an elliptic surface $E \rightarrow \mathbb{P}^1$ defined over $\mathbb{Q}$ is the smallest number field $k$ such that all of its $\Bar{\mathbb{Q}}(t)$-rational points are defined over $k(t)$. In this paper, we present an algorithm, implemented in \Magma{}, which can determine arithmetic information, including the field of definition, associated to any rational elliptic surface. As an application of this, we also demonstrate that the field of definition of Shioda's rank $68$ elliptic surface given by $y^2 = x^3 + t^{360} + 1$ is a number field of degree $829,440$.

2601.15204 2026-06-08 math.FA math.OA 版本更新

Embeddings of $L^p$-operator algebras

$L^p$-运算代数的嵌入

Eusebio Gardella, Jan Gundelach

AI总结 本文研究了来自(扭曲)Étale群oid的$L^p$-运算代数的嵌入,重点探讨$p\neq 2$时的刚性现象。通过分析核心正规化子及其在代数同态下的函子行为,证明了减少的$L^p$-群oid代数之间的嵌入可通过底层群oid的同态描述。并展示这些嵌入诱导了相关拓扑满群的嵌入。

Comments 39 pages. V2: no significant changes (fixed typos, streamlined some arguments, added acknowledgements)

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AI中文摘要

我们研究了来自(扭曲)Étale群oid的$L^p$-运算代数的嵌入,特别强调$p\neq 2$时的刚性现象。我们的方法依赖于对核心正规化子及其在代数同态下的函子行为的详细分析。利用群oid之间的actor概念,我们证明在自然假设下,减少的$L^p$-群oid代数之间的嵌入可通过底层群oid的同态完全描述。我们进一步证明,$L^p$-群oid代数的嵌入诱导了相关拓扑满群的嵌入。我们的结果提供了研究$L^p$-设定下嵌入性问题的新工具,并在排除嵌入存在性时特别有用。作为应用,我们获得了空间AF $L^p$-运算代数和$L^p$-Cuntz代数张量积的强嵌入性结果。对于$p\not \in \{1,2\}$,一个与主Étale群oid相关的减少的$L^p$-群oid代数嵌入到空间AF $L^p$-运算代数当且仅当底层群oid是AF的。特别是,与经典Pimsner-Voiculescu结果相反,非交换的$L^p$-流形对于$p\neq 2$不嵌入到空间AF $L^p$-运算代数中。此外,如果$p\neq 2$,则不存在从$\mathcal{O}_2^p \otimes_p \mathcal{O}_2^p$到$\mathcal{O}_2^p$的单位合同同态,显示不存在$L^p$-类比的Kirchberg的$\mathcal{O}_2$-嵌入定理。

英文摘要

We study embeddings of $L^p$-operator algebras arising from (twis\-ted) étale groupoids, with particular emphasis on rigidity phenomena for $p\neq 2$. Our methods rely on a detailed analysis of core normalizers and their functorial behavior under algebra homomorphisms. Using the notion of actors between groupoids, we show that under natural hypotheses, embeddings between reduced $L^p$-groupoid algebras can be described entirely in terms of morphisms of the underlying groupoids. We further show that embeddings of $L^p$-groupoid algebras induce embeddings of the associated topological full groups. Our results provide new tools for studying embeddability questions in the $L^p$-setting, and are particularly helpful when ruling out the existence of embeddings. As applications, we obtain strong embeddability results both for spatial AF $L^p$-operator algebras and for tensor products of $L^p$-Cuntz algebras. For $p\not \in \{1,2\}$, a reduced $L^p$-groupoid algebra associated with a principal étale groupoid embeds into a spatial AF $L^p$-operator algebra if and only if the underlying groupoid is AF. In particular, and in contrast with classical results of Pimsner-Voiculescu, irrational $L^p$-noncommutative tori do not embed into spatial AF $L^p$-operator algebras for $p\neq 2$. Furthermore, if $p\neq 2$, there is no unital contractive homomorphism from $\mathcal{O}_2^p \otimes_p \mathcal{O}_2^p$ into $\mathcal{O}_2^p$, showing that there is no $L^p$-analog of Kirchberg's $\mathcal{O}_2$-embedding theorem.

2508.20146 2026-06-08 cs.SI cs.CY 版本更新

What Causes COVID-19 Fear? General Drivers of Fear During a Health Crisis

什么是导致COVID-19恐惧的原因?在健康危机期间恐惧的普遍驱动因素

Daniele Baccega, Paolo Castagno, Antonio Fernández Anta, Juan Marcos Ramirez, Matteo Sereno

AI总结 本文研究了疫情期间个体对感染的恐惧来源,通过分析人口学变量、流行病学条件及信息源暴露,提出概率因果模型,发现信息源暴露对恐惧影响更大,且机构和专家信息源会增加恐惧,而政治人物和宗教领袖信息源会减少恐惧。

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AI中文摘要

COVID-19大流行不仅引发了全球健康危机,还引发了信息泛滥,暴露于异质信息源影响了公众情绪反应。本文通过Delphi US CTIS调查数据,研究自我报告感染恐惧的决定因素。我们分析人口学变量、流行病学条件及不同信息源暴露如何影响恐惧水平。我们引入概率因果模型来估计因果关系强度,识别对恐惧影响最大的变量。结果表明,信息源暴露对恐惧方差的解释比人口学和流行病学变量更大。我们进一步计算平均处理效应,量化不同信息源对恐惧的影响。在因果调整后,机构和专家驱动的信息源与更高的恐惧水平相关,而政治人物、宗教领袖和替代信息渠道与较低的恐惧水平相关。这些发现突显了信息生态系统在公共卫生危机中塑造情绪反应的核心作用,以及因果推断方法在研究疫情行为反应中的价值。

英文摘要

The COVID-19 pandemic triggered not only a global health crisis but also an infodemic, where exposure to heterogeneous information sources influenced public emotional responses. In this work, we investigate the determinants of self-reported fear of infection using data from the Delphi US CTIS survey. In particular, we analyze how demographic variables, epidemiological conditions, and exposure to different information sources shape fear levels. We introduce a Probabilistic Causal Model to estimate causal relationship strengths, identifying the variables that most strongly influence fear. Our results indicate that exposure to information sources accounts for a greater proportion of the variance in fear than demographic and epidemiological variables do. We further compute the Average Treatment Effect to quantify the impact of different information sources on fear. After causal adjustment, institutional and expert-driven sources are associated with increased fear levels, whereas politicians, religious leaders, and alternative information channels are associated with reduced fear. These findings highlight both the central role of the information ecosystem in shaping emotional responses during public health crises and the value of causal inference approaches for studying behavioral responses to pandemics.

2601.13492 2026-06-08 astro-ph.GA astro-ph.CO 版本更新

Initial Investigations of the Outskirts of XLSSC 122

XLSSC 122外围区域的初步研究

Eleanore. B. Todd, Jon. P. Willis, Rebecca. E. A. Canning, Ophélie. K. Leste, Rahma. Alfarsy, Steven W. Allen, Gabriel Brammer, Joseph. N. Burchett, Adam. B. Mantz, Spencer. A. Stanford

AI总结 利用哈勃空间望远镜对红移1.98的星系团XLSSC 122进行研究,发现成员星系红分数随进入中心区而迅速增加,暗示存在快速淬熄机制,如湍流压力剥离。

Comments Accepted to Monthly Notices of the Royal Astronomical Society, 24 pages, 14 figures, 3 tables

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Journal ref
Monthly Notices of the Royal Astronomical Society, Volume 546, Issue 3,March 2026, stag140
AI中文摘要

我们利用哈勃空间望远镜对红移1.98的星系团XLSSC 122进行了研究,从中心到3 Mpc范围(相当于R500=295 kpc半径的10倍)。我们提供了扩展的光度和光谱目录,将光谱分类成员星系总数增加到74个,其中35个新增成员星系位于外围区域。我们计算了星系径向数密度分布,未发现明显的塌缩团或宇宙丝结构。我们观察到成员星系中存在明显的双峰颜色关系,红分数随中心区增加而上升。这种红分数在进入中心区时的快速增加表明存在快速淬熄机制,如湍流压力剥离。我们拟合了星系团成员的光度函数,发现低质量斜率相似但光度尺度更暗,暗示与较低红移的类似温度星系团相似的星系演化速率。

英文摘要

We investigate the redshift 1.98 galaxy cluster XLSSC 122 using the Hubble Space Telescope (HST) from the core of the cluster out to 3 Mpc, a scale equivalent to 10 times the R500 = 295 kpc radius. We present an expanded photometric and spectroscopic catalogue of the cluster, bringing the total number of spectroscopically classified member galaxies to 74, with 35 new member galaxies added in the outer regions of the cluster. We compute the radial galaxy number density profile in the cluster, and observe no clear evidence of infalling groups or cosmic filaments. We observe a clear bimodal colour relation in member galaxies, with red fraction increasing towards the cluster centre. This rapid increase of red fraction upon infall is indicative of a fast quenching mechanism, such as ram pressure stripping, as galaxies enter the cluster centre. We fit a luminosity function to the cluster members, finding a similar low mass slope but fainter scale magnitude than z = 1 clusters of similar temperature, implying a similar galaxy evolution rate to clusters at lower redshift.

2601.13421 2026-06-08 q-fin.TR q-fin.MF 版本更新

Market Making and Transient Impact in Spot FX

外汇市场中的做市与瞬时影响

Alexander Barzykin

AI总结 本文研究外汇市场中做市商在考虑风险管理和市场影响时的最优策略,探讨瞬时影响与永久影响之间的平衡。

Comments 8 pages, 3 figures

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AI中文摘要

外汇市场中的做市商通过提供买入和卖出价格来服务客户,这些价格是他们愿意买入和卖出的价格。为了管理风险,做市商可以调整报价并在银行间市场进行对冲。对冲提供了确定性,但伴随着交易成本和市场影响。具有执行的最优做市策略此前已在Almgren-Chriss市场影响模型中得到研究,该模型包括瞬时和永久组成部分。然而,有大量的实证证据表明市场影响具有短暂的性质,瞬时和永久影响作为两种极限情况出现。在本笔记中,我们考虑一个中间场景,研究风险管理和影响韧性之间的相互作用。

英文摘要

Dealers in foreign exchange markets provide bid and ask prices to their clients at which they are happy to buy and sell, respectively. To manage risk, dealers can skew their quotes and hedge in the interbank market. Hedging offers certainty but comes with transaction costs and market impact. Optimal market making with execution has previously been addressed within the Almgren-Chriss market impact model, which includes instantaneous and permanent components. However, there is overwhelming empirical evidence of the transient nature of market impact, with instantaneous and permanent impacts arising as the two limiting cases. In this note, we consider an intermediate scenario and study the interplay between risk management and impact resilience.

2601.07874 2026-06-08 math.AG math.AC 版本更新

On Strong Lefschetz Property of 0-dimensional Complete Intersections and Associated Forms

关于零维完全交集的强Lefschetz性质及关联形式

Zhenjian Wang

AI总结 研究零维完全交集满足强Lefschetz性质的条件,证明其关联形式的Hessian非零,探讨关联形式的重建方法及其在Jacobian理想中的应用。

Comments add discussions on properties of associated forms; prove that a generic homogeneous polynomial can be reconstructed from any nontrivial graded component of its Jacobian ideal

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AI中文摘要

我们证明,一个齐次零维完全交集在度数1时满足强Lefschetz性质当且仅当其关联形式的Hessian非零。此结果在文献中已知,但我们的证明方法不同。我们进一步研究关联形式的性质,证明它们总能从其偏导数(特别是Jacobian理想)中重建。作为我们方法的应用,我们证明了每个非Sebastiani-Thom类型的光滑齐次多项式由其Jacobian理想中的任意非平凡次多项式唯一确定。

英文摘要

We prove that a homogeneous 0-dimensional complete intersection satisfies the Strong Lefschetz Property (SLP) in degree 1 if and only if its associated form has nonzero Hessian. This result is essentially known in the literature, but our proof differs from previous ones. We then investigate properties of the associated forms and show that they can always be reconstructed from their partial derivatives, in particular from their Jacobian ideals. As an application of our method, we prove that every smooth homogeneous polynomial which is not of Sebastiani-Thom type is uniquely determined by any nontrivial graded component of its Jacobian ideal.

2601.11131 2026-06-08 math.NT 版本更新

Deterministic methods for finding elements of large multiplicative order

确定性方法寻找大乘法阶元素

David Harvey, Markus Hittmeir

AI总结 本文提出确定性算法,无需假设D≥N^(2/5)即可找到大阶元素或非平凡因数,且当N为素数时可保证返回大阶元素。

Comments 13 pages; slightly improved main complexity bound

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AI中文摘要

我们重新审视了在自然数N的乘法群中严格且确定性地找到大阶元素的问题。解决此问题是几种最近确定性因数分解算法的关键步骤,包括目前最快的算法。2018年,第二作者提出一个算法,对于给定的目标阶D≥N^(2/5),找到阶超过D的元素、N的非平凡因数,或证明N为素数。运行时间是O(D^(1/2)/(log log D)^(1/2) log²N)位运算,渐近与使用Sutherland优化的经典baby-step-giant-step方法计算单个元素阶的成本相同。后续作者的工作将假设D≥N^(2/5)弱化为D≥N^(1/6)。本文展示假设可完全删除。此外,若N为素数,我们可保证返回阶超过D的元素,而非证明N为素数。

英文摘要

We revisit the problem of rigorously and deterministically finding elements of large order in the multiplicative group of integers modulo a natural number $N$. Solving this problem is an essential step in several recent deterministic algorithms for factoring $N$, including the currently fastest ones. In 2018, the second author gave an algorithm that for a given target order $D \geq N^{2/5}$, finds either an element of order exceeding $D$, or a nontrivial divisor of $N$, or proves that $N$ is prime. The running time was \[ O\left(\frac{D^{1/2}}{(\log \log D)^{1/2}} \log^2 N \right) \] bit operations, asymptotically the same as the cost of computing the order of a single element using Sutherland's optimisation of the classical babystep-giantstep method. Subsequent work by several authors weakened the hypothesis $D \geq N^{2/5}$ to $D \geq N^{1/6}$. In this paper, we show that the hypothesis may be dropped altogether. Moreover, if $N$ is prime, we can guarantee returning an element of order exceeding $D$, rather than a proof that $N$ is prime.

2601.10474 2026-06-08 math.NA cs.NA 版本更新

Optimal error estimates for a discontinuous Galerkin method on curved boundaries with polygonal meshes

针对曲边边界上多边形网格的不连续伽辽金方法的最优误差估计

Adérito Araújo, Milene Santos

AI总结 本文研究了在曲边边界上使用多边形网格的不连续伽辽金方法,通过多项式重构边界数据的方法,证明了在合适正则性假设下,该方法在二维线性对流-扩散-反应问题中实现最优收敛性。

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AI中文摘要

我们考虑了用于求解二维带有曲边边界的边界值问题的不连续伽辽金方法。在这种情况下,一个关键挑战是由于用多边形网格近似物理域而可能损失收敛阶。除非边界条件能准确从真实边界转移到计算边界,此类几何近似误差通常会导致次优收敛。为克服这一限制,一种基于多项式重构边界数据的更高阶策略被引入到经典有限元方法中[31, 32]以及有限体积上下文中[8, 14]。最近,这种方法被扩展到不连续伽辽金方法中[35],导致DG-ROD方法,该方法在具有曲边边界的域的多边形近似上恢复了最优收敛率。在本工作中,我们为DG-ROD方法提供了严谨的理论分析,建立了离散解的存在性和唯一性,并推导了二维线性对流-扩散-反应问题在凸和非凸域上具有齐次Dirichlet边界条件的误差估计。遵循并扩展经典有限元方法[32]中的技术,我们证明,在合适的正则性假设下,DG-ROD方法在多边形近似下实现最优收敛性。最后,我们通过考虑三角形网格的数值基准来说明和验证这些理论结果。

英文摘要

We consider a discontinuous Galerkin method for the numerical solution of boundary value problems in two-dimensional domains with curved boundaries. A key challenge in this setting is the potential loss of convergence order due to approximating the physical domain by a polygonal mesh. Unless boundary conditions can be accurately transferred from the true boundary to the computational one, such geometric approximation errors generally lead to suboptimal convergence. To overcome this limitation, a higher-order strategy based on polynomial reconstruction of boundary data was introduced for classical finite element methods in [31, 32] and in the finite volume context in [8, 14]. More recently, this approach was extended to discontinuous Galerkin methods in [35], leading to the DG-ROD method, which restores optimal convergence rates on polygonal approximations of domains with curved boundaries. In this work, we provide a rigorous theoretical analysis of the DG-ROD method, establishing existence and uniqueness of the discrete solution and deriving error estimates for a two-dimensional linear advection-diffusion-reaction problem with homogeneous Dirichlet boundary conditions on both convex and non-convex domains. Following and extending techniques from classical finite element methods [32], we prove that, under suitable regularity assumptions on the exact solution, the DG-ROD method achieves optimal convergence despite polygonal approximations. Finally, we illustrate and confirm the theoretical results with a numerical benchmark considering triangular meshes

2509.09964 2026-06-08 cond-mat.mtrl-sci cond-mat.mes-hall 版本更新

Scaling Nanoribbon Transistors with Monolayer Transition Metal Dichalcogenides

单层过渡金属二硫族化物实现高性能纳米带晶体管

Tara Peña, Anton E. O. Persson, Andrey Krayev, Áshildur Friðriksdóttir, Haotian Su, Yuan-Mau Lee, Young Suh Song, Kathryn Neilson, Zhepeng Zhang, Anh Tuan Hoang, Jerry A. Yang, Lauren Hoang, Shan X. Wang, Andrew J. Mannix, Paul C. McIntyre, Eric Pop

AI总结 通过多图案化工艺制备基于单层过渡金属二硫族化物的n型和p型纳米带晶体管,实现25-30 nm的沟道宽度和长度,在1 V漏源电压下达到高达560、420和130 μA μm⁻¹的导通电流,性能远超此前报道。

Comments 22 pages, 9 figures

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AI中文摘要

纳米尺度晶体管需要激进地缩减所有沟道维度:长度、宽度和厚度。虽然单层二维半导体(2DS)提供了终极的厚度缩减,但良好的性能主要仅在微米宽的沟道中实现。这里,我们展示了基于单层2DS的n型和p型纳米带晶体管,通过多图案化工艺制备,沟道宽度和长度可低至25-30 nm。“锚定”接触提高了器件良率,而纳米级成像(包括尖端增强光致发光)显示边缘退化极小。器件在1 V漏源电压下,对于n型MoS₂、WS₂和p型WSe₂,分别达到高达560、420和130 μA μm⁻¹的导通电流,并与薄的高κ电介质集成。这些结果超越了此前单栅纳米带晶体管的报道,WS₂器件甚至提高了100倍以上,即使在常关(增强模式)晶体管中也是如此。综合这些发现表明,自上而下图案化的2DS纳米带是未来纳米片晶体管的有前景的构建模块。

英文摘要

Nanoscale transistors require aggressive reduction of all channel dimensions: length, width, and thickness. While monolayer two-dimensional semiconductors (2DS) offer ultimate thickness scaling, good performance has largely been achieved only in micrometer-wide channels. Here, we demonstrate both $\it{n}$- and $\it{p}$-type nanoribbon transistors based on monolayer 2DS, fabricated using a multi-patterning process, reaching channel widths and lengths down to 25-30 nm. 'Anchored' contacts improve device yield, while nanoscale imaging, including tip-enhanced photoluminescence, reveals minimal edge degradation. The devices reach on-state currents up to 560, 420, and 130 $μ$A $μ$m$^{-1}$ at 1 V drain-to-source voltage for $\it{n}$-type MoS$_{2}$, WS$_{2}$, and $\it{p}$-type WSe$_{2}$, respectively, integrated with thin high-$κ$ dielectrics. These results surpass prior reports for single-gated nanoribbons, the WS$_{2}$ by over 100 times, even in normally off (enhancement-mode) transistors. Taken together, these findings suggest that top down patterned 2DS nanoribbons are promising building blocks for future nanosheet transistors.

2601.07622 2026-06-08 cs.IT cs.SY eess.SY math.IT 版本更新

Clipped Affine Policy: Low-Complexity Near-Optimal Online Power Control for Energy Harvesting Communications over Fading Channels

截断仿射策略:低复杂度近优在线功率控制用于衰落信道上的能量收集通信

Hao Wu, Shengtian Yang, Huiguo Gao, Diao Wang, Jun Chen, Guanding Yu

AI总结 本文提出基于相对价值函数的截断仿射策略,用于衰落信道上的能量收集通信在线功率控制,通过乐观与稳健策略实现低复杂度近优控制,在多种场景中性能优于基准方法。

Comments 29 pages, 15 figures, v1.0

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AI中文摘要

本文研究了在慢衰落信道中受限电池点对点能量收集通信的在线功率控制。通过贝尔曼方程中的相对价值函数开发线性策略近似,得到两种参数化截断仿射策略:乐观策略和稳健策略。对于独立同分布的能量到达和信道状态,基于乐观截断仿射(OCA)和稳健截断仿射(RCA)策略分别开发了两种功率控制方案。进一步扩展到四种带有上下文信息的场景:一步能量预览、一步信道预览、一步联合能量-信道预览以及马尔可夫能量到达。大量仿真结果表明,所提方案在计算复杂度和性能之间取得良好平衡。基于最大化最优线性策略斜率近似的自适应RCA策略(RCA-OLA-A)和RCA-RL方案在总体性能上表现最佳,而基于最大化最优线性策略的RCA策略(RCA-OL)是最佳的闭式解策略。特别地,RCA-OLA-A、RCA-RL及其上述RCA-RL扩展在各种场景中相对于最优策略的性能损失小于2%,优于所有考虑的基准方法,包括通用强化学习基线。RCA-OL策略在性能上也表现良好,其性能损失小于4%。

英文摘要

This paper studies online power control for battery-limited point-to-point energy harvesting communications over slow block-fading channels. A linear-policy-based approximation is developed for the relative-value function in the Bellman equation of the power control problem. This approximation leads to two fundamental parameterized clipped affine policies: an optimistic policy derived from a certainty-equivalence-type approximation and a robust policy derived from worst-case analysis. For independent and identically distributed energy arrivals and channel states, two families of power control schemes are developed based on the optimistic clipped affine (OCA) and robust clipped affine (RCA) policies, respectively. The proposed adaptive RCA policy based on reinforcement learning (RCA-RL) is further extended to address four scenarios with contextual information: one-step energy lookahead, one-step channel lookahead, one-step joint energy-channel lookahead, and Markov energy arrivals. Extensive simulation results show that the proposed schemes provide a favorable tradeoff between computational complexity and performance. The adaptive RCA policy based on the maximin optimal linear-policy-slope approximation (RCA-OLA-A) and the RCA-RL scheme achieve the best overall performance, while the RCA policy based on the maximin optimal linear policy (RCA-OL) is the best-performing closed-form policy. In particular, RCA-OLA-A, RCA-RL, and the aforementioned RCA-RL extensions achieve less than 2% performance loss relative to the optimal policy across a range of scenarios, consistently outperforming the considered benchmark approaches, including generic reinforcement learning baselines. The RCA-OL policy also performs well with less than 4% performance loss.

2601.05522 2026-06-08 cond-mat.mtrl-sci 版本更新

Unusually high phonon thermal conductivity in the Weyl semimetal TaP: A comparative study with TaAs

TaP中异常高的声子热导率:与TaAs的比较研究

Xianyong Ding, Xin Jin, Dengfeng Li, Jing Fan, Peng Yu, Xiaoyuan Zhou, Xiaolong Yang, Rui Wang

AI总结 研究揭示Weyl半金属TaAs和TaP中声子主导的热传输机制,TaP在室温下声子热导率高达162 Wm⁻¹K⁻¹,远超电子导热,源于独特的能带结构抑制声子-电子及三声子散射。

Comments 11pages,6figures

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AI中文摘要

在许多金属中,热传输通常由电子主导,但材料不同,晶格贡献可能显著。通过严格的第一性原理计算,我们发现Weyl半金属TaAs和TaP中声子主导的热传输机制。值得注意的是,尽管TaP具有金属特性,其在室温下的声子热导率(κ_ph)高达162 Wm⁻¹K⁻¹,超过其电子导热约一个数量级。这种异常高的κ_ph由独特的电子和声子能带结构实现,包括费米能级附近的Weyl节点、声子聚束和声子频谱中的宽频隙,这些共同抑制了声子-电子及三声子散射过程。费米能级附近线性分散的能带导致电子态密度低,从而限制了这些Weyl半金属的电导率和电子热传输。进一步调研多种拓扑半金属后,我们表明声子热传输的显著性是此类材料的普遍特征。本工作为拓扑半金属的热传输机制提供了更深入的理解,并拓宽了发现高热导率金属的视野。

英文摘要

In many metals, thermal transport is often dominated by electrons, although the lattice contribution can remain appreciable depending on the material. Here, through rigorous first-principles calculations, we uncover a phonon-dominated thermal transport regime in the Weyl semimetals TaAs and TaP. Remarkably, despite its metallic character, TaP exhibits an exceptionally high phonon thermal conductivity ($κ_{\text{ph}}$) of 162 Wm$^{-1}$K$^{-1}$ at room temperature, surpassing its electronic counterpart by nearly an order of magnitude. This anomalously high $κ_{\text{ph}}$ is enabled by the unique electronic and phononic band structures, including the Weyl nodes near the Fermi level, acoustic phonon bunching, and a wide frequency gap in the phonon spectrum, which collectively suppress phonon-electron and three-phonon scattering processes. The linearly dispersing bands near the Fermi level give rise to a low electronic density of states, thereby limiting both electrical conductivity and electronic thermal transport in these Weyl semimetals. By further surveying a broad range of topological semimetals, we show that the prominence of phonon thermal transport is a universal characteristic of this material class. Our work provides deeper insight into thermal transport mechanisms in topological semimetals and broadens the scope for discovering metals with high thermal conductivity.

2601.05669 2026-06-08 stat.ME 版本更新

Two-Stage Robust Sparse Gradient Methods for Regression Under Heavy-Tailed Designs

重尾设计下回归的两阶段鲁棒稀疏梯度方法

Kaiyuan Zhou, Xiaoyu Zhang, Wenyang Zhang, Di Wang

AI总结 针对重尾协变量和噪声下的高维稀疏回归,提出两阶段RIGHT方法,利用坐标-wise中位数均值梯度估计和延迟样本分裂,实现相位自适应收敛,并揭示设计尾指数与噪声尾指数对梯度稳定性和统计速率的解耦影响。

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AI中文摘要

我们研究在同时具有重尾协变量和噪声的高维稀疏回归。重尾数据以两种不同方式影响稀疏优化:极端协变量可能在全局定位期间破坏梯度场,而重尾噪声在局部细化期间限制最终统计精度。受这种两阶段结构的启发,我们提出两阶段RIGHT,一种基于坐标-wise中位数均值(MoM)梯度估计和延迟样本分裂的鲁棒稀疏一阶方法。MoM梯度估计器计算简单,与硬阈值更新兼容,并允许相位自适应浓度界,其速率取决于当前定位半径。延迟分裂在全局定位期间重用数据,并为较短的细化阶段保留新批次,从而降低样本分裂成本。理论结果揭示了解耦的速率结构:设计尾指数控制梯度稳定性和样本复杂度,而噪声尾指数控制最终统计速率。我们还提供了相位-wise下界基准,表明设计驱动的定位障碍是内在的。广泛的模拟实验和真实数据分析展示了所提方法相对于现有竞争者的有效性。

英文摘要

We study high-dimensional sparse regression under simultaneous heavy-tailed covariates and noise. Heavy-tailed data affect sparse optimization in two different ways: extreme covariates can destabilize the gradient field during global localization, while heavy-tailed noise limits the final statistical accuracy during local refinement. Motivated by this two-phase structure, we propose two-stage RIGHT, a robust sparse first-order method based on coordinate-wise median-of-means (MoM) gradient estimation and delayed sample splitting. The MoM gradient estimator is computationally simple, compatible with hard-thresholded updates, and admits phase-adaptive concentration bounds whose rates depend on the current localization radius. Delayed splitting reuses data during global localization and reserves fresh batches for the shorter refinement stage, reducing the sample-splitting cost. The theoretical results reveal a decoupled rate structure: the design-tail index controls gradient stability and sample complexity, whereas the noise-tail index controls the final statistical rate. We also provide phase-wise lower-bound benchmarks showing that the design-driven localization barrier is intrinsic. Extensive simulation experiments and real data analysis showcase the efficacy of the proposed method over existing competitors.

2601.03968 2026-06-08 math.AP 版本更新

The uniqueness and concentration behavior of solutions for a nonlinear fractional Schrödinger system

非线性分数阶薛定谔系统的解的唯一性和集中行为

Chungen Liu, Zhigao Zhang, Jiabin Zuo

AI总结 本文研究了二维耦合分数阶薛定谔方程组的解的唯一性及集中行为,通过L^2约束极小化问题和隐函数定理证明了解的唯一性,并分析了在临界值附近解的集中现象及爆破速率。

Comments 26 pages

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AI中文摘要

本文研究了在$\mathbb{R}$中具有吸引内种和吸引异种相互作用的非线性两个耦合分数阶薛定谔方程组。通过分析相关的L^2约束极小化问题,利用隐函数定理证明了解的唯一性。在某种捕获势下,通过建立精细的能量估计,详细分析了解在总内种和异种相互作用强度趋于临界值时的集中行为,其中每个分量在相关捕获势的最平坦公共最小点处爆破并集中。还给出了该系统解的最优爆破速率。

英文摘要

The paper is concerned with a nonlinear system of two coupled fractional Schrödinger equations with both attractive intraspecies and attractive interspecies interactions in $\mathbb{R}$. By analyzing an associated $L^2$-constrained minimization problem, the uniqueness of solutions to this system is proved via the implicit function theorem. Under a certain type of trapping potential, by establishing some delicate energy estimates, we present a detailed analysis on the concentration behavior of the solutions as the total strength of intraspecies and interspecies interactions tends to a critical value, where each component of the solutions blows up and concentrates at a flattest common minimum point of the associated trapping potentials. An optimal blow-up rate of solutions to the system is also given.

2509.12952 2026-06-08 cond-mat.mtrl-sci 版本更新

Origin of Anomalous Size Effects in Ferroelectric Hafnia Thin Films

铁电氧化铪薄膜中异常尺寸效应的起源

Tianyuan Zhu, Jingxuan Li, Zuhuang Chen, Shi Liu

AI总结 研究揭示了铁电氧化铪超薄薄膜中异常尺寸效应的成因,通过理论与模型分析发现,残余极化场的负纵向压电响应与表面应力的正效应共同导致晶格膨胀,且通过取向工程可实现超铁电性,为器件集成提供新策略。

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AI中文摘要

超薄HfO₂薄膜中铁电性的持续存在挑战了传统理论,尤其是当薄膜厚度减小时,晶格间距异常增加的现象。本文通过第一性原理计算与解析建模揭示,这种晶格膨胀与极化抑制的反直觉耦合有关。两种机制:残余极化场的负纵向压电响应和表面应力的正效应共同导致晶格膨胀。此外,(111)取向的HfO₂薄膜在开路条件下可支持垂直极化,而(001)取向的薄膜则稳定非极性基态。这种行为表明了取向诱导的超铁电性,一种未被识别的机制,通过取向工程可实现极化持续,无需电极屏蔽。进一步研究显示,这一原理可推广至传统钙钛矿如PbTiO₃,提供消除临界厚度限制的策略。作为器件集成的实用路径,还识别出二维电极Ca₂N为近理想电极,可完全恢复超薄电容器中HfO₂的铁电性质。

英文摘要

The persistence of ferroelectricity in ultrathin HfO$_2$ films challenges conventional theories, particularly given the paradoxical observation that the out-of-plane lattice spacing increases as the film thickness decreases, an anomalous size effect absent in perovskite ferroelectrics. Here, we resolve this puzzle by revealing that this lattice expansion is counterintuitively coupled to a suppressed out-of-plane polarization. First-principles calculations combined with analytical modeling identify two mechanisms behind this expansion: a negative longitudinal piezoelectric response to the residual depolarization field and a positive surface stress that becomes significant at reduced thickness. Their interplay quantitatively reproduces the experimentally observed lattice expansion. Furthermore, (111)-oriented HfO$_2$ films can support out-of-plane polarization even under open-circuit conditions, in contrast to (001) films that stabilize a nonpolar ground state. This behavior points to the emergence of orientation-induced hyperferroelectricity, an unrecognized mechanism that enables polarization persistence through orientation engineering without electrode screening. We further demonstrate that this principle generalizes to conventional perovskites such as PbTiO$_3$, offering a strategy to eliminate the critical thickness limit by choosing the appropriate film orientation. As a practical pathway to device integration, we also identify the two-dimensional electride Ca$_2$N as a near-ideal electrode that fully restores the ferroelectric properties of HfO$_2$ in ultrathin capacitors.

2601.03257 2026-06-08 astro-ph.CO gr-qc 版本更新

Heavy Black-Holes Also Matter in Standard Siren Cosmology

大质量黑洞在标准声纳宇宙学中同样重要

Grégoire Pierra, Alexander Papadopoulos

AI总结 本文研究了大质量黑洞对宇宙学参数估计的影响,利用GWTC-4.0中的142个 CBCs 数据,通过光谱和暗声纳方法提高了Hubble常数的精度,发现新的质量尺度对Hubble常数有额外约束。

Comments 5 pages, 4 figures

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AI中文摘要

随着LIGO-Virgo-KAGRA合作组织发布的引力波暂态目录GWTC-4.0,218个引力波候选检测已被报告。这一里程碑标志着引力波宇宙学的重大进展,因为许多方法,特别是利用光谱声纳方法的,都依赖于可用源的数量。我们研究了描述CBCs完整质量谱的新参数模型对Hubble常数估计的影响。该模型旨在测试大质量黑洞在引力波宇宙学中的影响。我们使用142个GWTC-4.0中的CBCs,结合光谱和暗声纳方法,进行宇宙学和人口参数的联合推断,假警报率小于每年0.25。通过光谱声纳,我们估计Hubble常数为H₀=78.8±19.0⁻15.3 km s⁻¹ Mpc⁻¹(68%置信区间),而暗声纳方法得到H₀=82.5±16.8⁻14.3 km s⁻¹ Mpc⁻¹(68%置信区间)。这些结果将不确定性提高了约30.4%和36.2%。我们展示这种改进与二进制黑洞质量谱中新的质量尺度的存在有关,该尺度在63.3±4.8 M☉处,为Hubble常数提供了额外约束。除了提供最紧的标准声纳约束外,这还突显了黑洞谱中大质量特征的重要性。

英文摘要

With the release of the Gravitational-Wave Transient Catalog GWTC-4.0 by the LIGO-Virgo-KAGRA (LVK) collaboration, 218 candidate detections of gravitational waves (GWs) from compact binary coalescences (CBCs) have been reported. This milestone represents a major advancement for GW cosmology, as many methods, particularly those employing the spectral siren approach, critically depend on the number of available sources. We investigate the impact of a novel parametric model describing the full population mass spectrum of CBCs on the estimation of the Hubble constant. This model is designed to test the impact of heavy black holes in GW cosmology. We perform a joint inference of cosmological and population parameters using 142 CBCs from GWTC-4.0 with a false alarm rate smaller than 0.25 per year, using both spectral and dark siren approaches. With spectral sirens, we estimate the Hubble constant to be $H_0 = 78.8^{+19.0}_{-15.3}\,{\rm km s^{-1} Mpc^{-1}}$ (68% CL), while the dark siren method yields $H_0 = 82.5^{+16.8}_{-14.3}\,{\rm km s^{-1} Mpc^{-1}}$ (68% CL). These results improve the uncertainty by approximately 30.4% and 36.2%, respectively. We show that this improvement is linked to the presence of a new mass scale in the binary black hole mass spectrum at $63.3^{+4.8}_{-4.8}\,M_{\odot}$, which provides additional constraints on the Hubble constant. Besides providing the tightest standard-siren constraints on $H_0$, this highlights the importance of a heavy-mass feature in the black hole spectrum.

2512.24932 2026-06-08 math.AG math.CV math.DG 版本更新

Generalised Hermite-Einstein Fibre Metrics and Slope Stability for Holomorphic Vector Bundles

广义Hermite-Einstein纤维度量与全纯向量丛的斜稳定性

Dan Popovici

AI总结 本文研究了基于Kähler度量和弱正形式的广义Hermite-Einstein全纯向量丛及其稳定性条件,扩展了Kobayashi和Lübke的经典结果。

Comments 34 pages; an entirely new appendix (pages 14-34), in which notions of strong and weak (strict) positivity for forms and currents are introduced and studied, has been added to the revised version;

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AI中文摘要

设X为维数为n的紧复流形,m为正整数且m≤n。假设X存在Kähler度量ω和一个弱正、∂∂̄闭合、光滑的(n−m,n−m)形式Ω。本文引入了依赖于ω的广义Hermite-Einstein全纯向量丛和全纯sheaves的稳定性概念。证明了广义Hermite-Einstein条件蕴含了稳定性,并扩展了Kobayashi和Lübke的经典结果。附录中提出了强和弱(严格)正形式和currents的概念,并讨论了它们的各种性质。

英文摘要

Let $X$ be a compact complex manifold of dimension $n$ and let $m$ be a positive integer with $m\leq n$. Assume that $X$ admits a Kähler metric $ω$ and a weakly positive, $\partial\bar\partial$-closed, smooth $(n-m,\,n-m)$-form $Ω$. We introduce the notions of $(ω,\,Ω)$-Hermite-Einstein holomorphic vector bundles and $(ω,\,Ω)$(-semi)-stable coherent sheaves on $X$ by generalising the classical definitions depending only on $ω$. We then prove that the $(ω,\,Ω)$-Hermite-Einstein condition implies the $(ω,\,Ω)$-semi-stability of a holomorphic vector bundle and its splitting into $(ω,\,Ω)$-stable subbundles. This extends a classical result by Kobayashi and Lübke to our generalised setting. In the appendix, we propose notions of both strongly and weakly (strictly) positive forms and currents and discuss their various properties.

2512.24869 2026-06-08 cond-mat.other cond-mat.dis-nn 版本更新

Regularized universal topological markers for Dirac systems

正则化的狄拉克系统通用拓扑标记

Yulin Qin, Chang-An Li, Jian Li

AI总结 本文提出正则化的通用拓扑标记,用于狄拉克系统,通过兼容周期边界条件的位置算子消除边界不规则性,并与Bott指数和旋磁数建立联系,用于检测拓扑相变。

Comments 11 pages, 5 figures

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Journal ref
Phys. Rev. B 113, 214201 (2026)
AI中文摘要

拓扑标记提供了一种高效且强大的方法来表征许多系统的拓扑特征,尤其是在翻译对称性被打破时。最近,提出了一种适用于不同对称类的通用拓扑标记。然而,它在边界处表现出不规则行为,且与其他拓扑指标的关系仍不清楚。本文通过利用兼容周期边界条件的位置算子,构建了适用于狄拉克系统的正则化通用拓扑标记。正则化标记成功消除了阻碍性的边界不规则性,并在整合所有晶格点时产生所需的全局拓扑不变量,如陈数。此外,正则化形式使我们能够明确地将标记与其他已知的拓扑指标联系起来。例如,它在A、D和C类中等同于Bott指数,在DIII和AII类中等同于旋磁数。我们进一步检查了该标记在无序情况下的效用和稳定性。发现其方差在相界处出现峰值,这使其成为检测由无序诱导的拓扑相变的有用指标。

英文摘要

Topological markers provide an efficient and powerful characterization of topological features of many systems, especially when the translation symmetry is broken. Recently, a universal topological marker applicable in different symmetry classes of topological systems is proposed. However, it suffers from irregular behaviors at the boundary and its connection to other topological indexes remains elusive. In this work, we construct regularized universal topological markers that apply to Dirac systems by utilizing position operators that are compatible with periodic boundary conditions. The regularized markers eliminate the obstructive boundary irregularities successfully and give rise to the desired global topological invariants, such as the Chern number, consistently when integrated over all the lattice sites. Furthermore, the regularized form allows us to establish an explicit connection between the markers and some other known topological indices in two dimensions. For instance, it turns out to be equivalent to the Bott index in classes A, D, and C and equivalent to the spin Chern number in classes DIII and AII. We further examine the utility and stability of this marker in disordered scenarios. We find that its variance shows peaks at the phase boundaries, which promotes it as a useful indicator for detecting disorder-induced topological phase transitions.

2512.18936 2026-06-08 math.NT 版本更新

Unimodular Fake Mobius Functions

单模伪莫比乌斯函数

Ali Saraeb

AI总结 研究单模伪莫比乌斯函数的分析与偏差理论,提出光滑求和函数的显式公式,并引入自然尺度下的偏差概念以区分持续偏差、表面偏差和无偏差。

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AI中文摘要

本文研究单模伪莫比乌斯函数的分析与偏差理论,提出光滑求和函数的显式公式,并引入自然尺度下的偏差概念以区分持续偏差、表面偏差和无偏差。

英文摘要

Let $\mathbb{S}^1$ denote the unit circle. We introduce and develop the analytic and bias theory of unimodular fake Möbius functions, i.e. multiplicative functions $\mathfrak{f}:\mathbb{N} \to \mathbb{S}^1 \cup \{0\}$ whose prime-power values are prescribed by a fixed sequence $\{\varepsilon_k\}_{k\ge1}$ via the rule $\mathfrak{f}(p^k)=\varepsilon_k$ for every prime $p$ and every $k\ge1$. A key feature of these functions is that their Dirichlet series admit a factorization into complex powers of the Riemann zeta function. Our main analytic result is an explicit formula for the smoothed summatory function $\sum_{n\ge1}\mathfrak{f}(n)e^{-n/x}$, consisting of a leading main term together with a sequence of lower-order terms. The formula may be viewed as an extension of the Selberg-Delange method and is expected to be of independent interest. As an application, we introduce a notion of bias at a natural scale and obtain an explicit criterion distinguishing persistent bias, apparent bias, and no bias for unimodular fake Möbius functions.

2307.15657 2026-06-08 cs.IT cs.CR cs.DM math.CO math.IT math.NT 版本更新

Almost perfect nonlinear power functions with exponents expressed as fractions

近完美非线性幂函数及其指数的分数表达

Daniel J. Katz, Kathleen R. O'Connor, Kyle Pacheco, Yakov Sapozhnikov

AI总结 本文研究了一类APN幂函数的指数表达形式,通过重新表述指数形式,实现了对差分谱的精确分析,并确定了任意差分导数纤维中的元素。

Comments 38 pages

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AI中文摘要

设F为有限域,f为从F到F的函数,a为F中的非零元素。f在方向a的离散导数Δ_a f: F→F定义为(Δ_a f)(x)=f(x+a)-f(x)。f的差分谱是所有导数Δ_a f的纤维大小的多重集。几乎完美非线性(APN)函数是指其差分谱中最大纤维大小为2的函数。APN函数在密码学中具有重要应用。若d为正整数,则F上的幂函数f: F→F定义为f(x)=x^d对所有x∈F。目前已知少数无限族的APN幂函数。本文重新表述了一类此类族的指数形式,使其更便于使用。这不仅使我们能够获得每个指数在该族中的幂函数的差分谱,还能够确定任意导数的纤维中的元素。通过将f的离散导数与某些置换和其域的双重覆盖组合,得到一个纤维更容易分析的函数,从而实现了比以前结果更详细的差分分析。

英文摘要

Let $F$ be a finite field, let $f$ be a function from $F$ to $F$, and let $a$ be a nonzero element of $F$. The discrete derivative of $f$ in direction $a$ is $Δ_a f \colon F \to F$ with $(Δ_a f)(x)=f(x+a)-f(x)$. The differential spectrum of $f$ is the multiset of cardinalities of all the fibers of all the derivatives $Δ_a f$ as $a$ runs through $F^*$. An almost perfect nonlinear (APN) function is one for which the largest cardinality in its differential spectrum is $2$. Almost perfect nonlinear functions are of interest as cryptographic primitives. If $d$ is a positive integer, then the power function over $F$ with exponent $d$ is the function $f \colon F \to F$ with $f(x)=x^d$ for every $x \in F$. There is a small number of known infinite families of APN power functions. In this paper, we re-express the exponents for one such family in a more convenient form. This enables us not only to obtain the differential spectrum of each power function $f$ with an exponent in our family, but also to determine the elements that lie in an arbitrary fiber of the discrete derivative of $f$. This differential analysis, which is far more detailed than previous results, is achieved by composing the discrete derivative of $f$ with some permutations and a double covering of its domain to obtain a function whose fibers can more readily be analyzed.

2512.23294 2026-06-08 eess.SY cs.SY 版本更新

Agentic AI-Enhanced Semantic Communications: Foundations, Architecture, and Applications

基于代理AI的语义通信:基础、架构与应用

Haixiao Gao, Mengying Sun, Ruichen Zhang, Yanhan Wang, Xiaodong Xu, Nan Ma, Dusit Niyato, Ping Zhang

AI总结 本文探讨代理AI如何赋能语义通信,提出统一框架并展示多场景应用,通过案例研究验证其有效性。

Comments This version is being withdrawn because we need to further reevaluate the attribution of contributions among the authors

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AI中文摘要

语义通信(SemCom)作为6G关键技术,正推动网络从比特传输转向语义信息交换。本文系统阐述代理AI如何从基础研究、系统架构和应用场景赋能SemCom。首先综述现有研究,涵盖嵌入式代理、大语言模型(LLM)/大视觉模型(LVM)代理和强化学习(RL)代理。提出统一的代理AI增强SemCom框架,涵盖应用层、语义层和云边协作层,形成意图到编码到传输到解码到行动到评估的闭环。展示多车辆协同感知、多机器人救援和智能网络代理操作等典型场景。引入基于代理知识库(KB)的联合源信道编码案例A-KB-JSCC,通过LLM/LVM代理和RL代理构建源KB和信道KB。实验结果表明AKB-JSCC在不同信道条件下实现更高的信息重构质量。最后讨论未来演进与研究方向,为可移植、可验证和可控的代理SemCom研究和部署提供参考。

英文摘要

Semantic communications (SemCom), as one of the key technologies for 6G, is shifting networks from bit transmission to semantic information exchange. On this basis, introducing agentic artificial intelligence (AI) with perception, memory, reasoning, and action capabilities provides a practicable path to intelligent communications. This paper provides a systematic exposition of how agentic AI empowers SemCom from the perspectives of research foundations, system architecture, and application scenarios. We first provide a comprehensive review of existing studies by agent types, covering embedded agents, large language model (LLM)/large vision model (LVM) agents, and reinforcement learning (RL) agents. Additionally, we propose a unified agentic AI-enhanced SemCom framework covering the application layer, the semantic layer, and the cloud-edge collaboration layer, forming a closed loop from intent to encoding to transmission to decoding to action to evaluation. We also present several typical scenarios, including multi-vehicle collaborative perception, multi-robot cooperative rescue, and agentic operations for intellicise (intelligent and concise) networks. Furthermore, we introduce an agentic knowledge base (KB)-based joint source-channel coding case study, AKB-JSCC, where the source KB and channel KB are built by LLM/LVM agents and RL agents, respectively. Experimental results show that AKB-JSCC achieves higher information reconstruction quality under different channel conditions. Finally, we discuss future evolution and research directions, providing a reference for portable, verifiable, and controllable research and deployment of agentic SemCom.

2512.07353 2026-06-08 eess.SY cs.SY 版本更新

Off-grid solar energy storage system with hybrid lithium iron phosphate (LFP) and lead-acid batteries in high mountains: a case report of Jiujiu Cabins in Taiwan

无电网太阳能储能系统:高海拔地区混合磷酸铁锂(LFP)与铅酸电池的应用:台湾九九小屋案例报告

Hsien-Ching Chung

AI总结 台湾九九小屋采用混合磷酸铁锂与铅酸电池的无电网太阳能储能系统,经历系统故障后通过修复和升级实现稳定供电,提升绿色能源应用。

Comments 14 pages, 9 figures, 4 tables

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AI中文摘要

山屋位于高海拔地区,为徒步者提供庇护所,其能源供应仍是个难题。台湾Shei-Pa国家公园著名的九九小屋曾运行无电网太阳能储能系统,2021年系统故障导致断电。经现场调查和修复后,系统恢复运行,并用环保的磷酸铁锂电池替代部分铅酸电池,形成混合储能系统,提升绿色无电网太阳能储能系统的性能。本文提供了系统架构、详细描述和历史状态,列出了故障系统调查、系统改进项目及未来计划。

英文摘要

Mountain huts are buildings located at high altitude, offering a place for hikers and providing shelter. Energy supply on mountain huts is still an open issue. Using renewable energies could be an appropriate solution. Jiujiu Cabins, a famous mountain hut in Shei-Pa National Park, Taiwan, has operated an off-grid solar energy storage system (ESS) with lead-acid batteries. In 2021, a serious system failure took place, leading to no electricity. After a detailed on-site survey, a reorganization and repair project implemented, the energy system came back to operate normally. Meanwhile, an eco-friendly lithium iron phosphate battery (LFP battery) ESS replaces part of the lead-acid battery ESS, forming a hybrid ESS, making a better and green off-grid solar ESS. In this case report, the energy architecture, detailed descriptions, and historical status of the system are provided. An on-site survey of the failed energy system, a system improvement project, and future plan are listed.

2512.18088 2026-06-08 cs.SE 版本更新

Detecting Flakiness in Quantum Software: A Dynamic Testing Approach

在量子软件中检测不稳定性:一种动态测试方法

Dongchan Kim, Hamidreza Khoramrokh, Lei Zhang, Andriy Miranskyy

AI总结 本文通过大规模动态分析量子软件中的不稳定性问题,发现尽管整体不稳定性率较低,但某些测试在多个版本中反复出现,需大量执行才能可靠检测。

Comments Improved detection robustness and added root-cause & fix-pattern analysis

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AI中文摘要

不稳定的测试是指在没有代码或环境变化的情况下随机通过或失败,对软件可靠性构成严重威胁。尽管经典软件工程已发展出丰富的技术研究不稳定性,但量子软件的相关证据有限。本文首次对量子软件中的不稳定性进行了大规模动态分析,聚焦于Qiskit Terra核心库。我们跨23个版本执行Qiskit Terra测试套件10,000次,在受控环境中进行。对于每个版本,我们测量测试结果的变异性,识别不稳定的测试,估计经验性失败概率,分析版本间的重复性,利用Wilson置信区间量化可靠检测的重跑预算,并将不稳定的测试映射到Terra子组件。在27,026个完整测试标识符中,我们发现了62个独特的不稳定的测试。尽管总体不稳定性率较低(0-0.17%),但重复性显著:62个不稳定的测试中有52个(83.87%)在多个版本中重现,而只有10个测试(16.13%)局限于单一版本。经验性失败概率跨度达多个数量级,中位数为$9 \times 10^{-4}$,34个测试(54.84%)在$10^{-3}$以下,这意味着可能需要数千到数万次执行才能可靠检测。这些结果表明,量子测试不稳定性虽然罕见,但在典型持续集成预算下难以检测。为支持未来研究,我们发布了包含每个测试执行结果的公开数据集。

英文摘要

Flaky tests, tests that pass or fail nondeterministically without changes to code or environment, pose a serious threat to software reliability. While classical software engineering has developed a rich body of techniques to study flakiness, corresponding evidence for quantum software remains limited. Prior work relies mainly on static analysis or small sets of manually reported incidents, leaving open questions about their prevalence, characteristics, and detectability. This paper presents the first large-scale dynamic characterization of flaky tests in quantum software, focusing on the Qiskit Terra core library. We executed the Qiskit Terra test suite 10,000 times across 23 releases in controlled environments. For each release, we measured test-outcome variability, identified flaky tests, estimated empirical failure probabilities, analyzed recurrence across versions, used Wilson confidence intervals to quantify rerun budgets for reliable detection, and mapped flaky tests to Terra subcomponents. Across 27,026 fully qualified test identifiers, we identified 62 unique flaky tests. Although overall flakiness rates were low (0-0.17%), recurrence was substantial: 52 of 62 flaky tests (83.87%) reappeared in multiple releases, while only 10 tests (16.13%) were confined to a single release. Empirical failure probabilities spanned several orders of magnitude, with a median of $9 \times 10^{-4}$ and 34 tests (54.84%) at or below $10^{-3}$, implying that thousands to tens of thousands of executions may be required for confident detection. These results show that quantum test flakiness is rare but difficult to detect under typical continuous integration budgets. To support future research, we release a public dataset of per-test execution outcomes.

2512.19833 2026-06-08 hep-ph 版本更新

Universal Seesaw Leptogenesis

通用见锯轻子生成

K. S. Babu, Maximilian Berbig, Srubabati Goswami, Drona Vatsyayan

AI总结 本文研究了一种左右对称模型中轻子生成的 implications,通过通用见锯机制生成所有费米子质量。模型利用 gauge-singlet 介子而非常规中微子衰变,避免了热化和洗出效应,并展示了低能标左右对称破缺的可行性。

Comments 44 pages, 4 figures, 1 table; v2: minor changes, matches published version

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Journal ref
JHEP 06 (2026) 020
AI中文摘要

我们研究了一类左右对称模型中轻子生成的 implications,其中所有费米子质量均通过通用见锯机制生成。与传统分析不同,我们不使用嵌入在右手性轻子双态中的中微子衰变,而是使用 gauge-singlet 介子的衰变,这些介子对于中微子质量生成是必要的。该模型具有广义的 parity 对称性,由强 CP 问题的解决方案所驱动。由于这种离散对称性在此模型中加倍了费米子的自由度,我们可以通过单一代言者生成所需的 CP 违反。我们场景的一个显著特点是,通常在传统左右对称模型中遇到的热化或 gauge 交互洗出效应在此不适用。此外,重介子可以衰变成左和右手性中微子,导致在左右对称破缺能标以上的重子不对称性抵消。我们讨论了避免这种抵消的方法,并显示低能标左右对称破缺在当前对撞机限制 $v_R > 18$ TeV 之上是可行的。右手性中微子也通过见锯机制获得质量,最轻的中微子质量在 sub-eV 量级。我们发现其丰度与标准宇宙学一致,并可能作为可观测的暗辐射。

英文摘要

We study the implications for leptogenesis in a class of left-right symmetric model, where all fermion masses are induced through the Universal Seesaw mechanism. Unlike conventional analyses, we do not use the decays of the neutrino embedded in the right-chiral lepton doublet, but rather those of the gauge-singlet mediators required for neutrino mass generation in the canonical Type-I seesaw. This model features a generalized parity symmetry, which is motivated by the solution to the strong $CP$ problem. Since this discrete symmetry doubles the fermionic degrees of freedom in this model, we can generate the required $CP$ violation in the heavy fermion decays with only a single generation of mediators. One of the distinct features of our scenario is that the bounds from thermalization or washout via gauge interactions typically encountered in the canonical left-right symmetric models do not apply here. Moreover, the heavy mediators can decay to both the left and the right-chiral neutrinos, leading to a cancellation in the resulting baryon asymmetry for decays above the left-right symmetry breaking scale. We discuss ways to avoid this cancellation and show that low scale left-right symmetry breaking above the current collider limits $v_R > 18$ TeV is viable. The right chiral neutrinos also obtain their masses from the seesaw mechanism, and the lightest one turns out to have a sub-eV scale mass. We find that its abundance is consistent with standard cosmology, and it acts as potentially observable dark radiation.