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2606.11790 2026-06-11 math.RT math.CO 新提交

A new proof for the partition algorithm of the annihilator varieties of highest weight modules

最高权模的零化子簇的划分算法的一个新证明

Zhanqiang Bai, Jing Jiang, Yongzhi Luan

AI总结 针对经典李代数最高权模的零化子簇对应的幂零轨道,Bai-Ma-Wang提出了划分算法,本文利用Sommers对偶给出了该算法的一个新直接证明。

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AI中文摘要

设 $L(\lambda)$ 是经典李代数 $\mathfrak{g}$ 上的一个简单最高权模,其最高权为 $\lambda-\rho$,其中 $\rho$ 是正根和的一半。Joseph 证明了 $L(\lambda)$ 的零化理想(也称为零化子簇)的相伴簇是 $\mathfrak{g}^*$ 中一个幂零轨道的 Zariski 闭包。最近,Bai--Ma--Wang 引入了一个划分算法来描述给定最高权模 $L(\lambda)$ 对应的这个幂零轨道。在本文中,我们利用 Sommers 对偶给出了 Bai--Ma--Wang 划分算法的一个新的直接证明。

英文摘要

Let $L(λ)$ be a simple highest weight module of a classical Lie algebra $\mathfrak{g}$ with highest weight $λ-ρ$, where $ρ$ is half the sum of positive roots. Joseph proved that the associated variety of the annihilator ideal of $L(λ)$ (also called the annihilator variety) is the Zariski closure of a nilpotent orbit in $\mathfrak{g}^*$. Recently, Bai--Ma--Wang introduced a partition algorithm to describe this corresponding nilpotent orbit for a given highest weight module $L(λ)$. In this paper, we present a new direct proof of Bai--Ma--Wang's partition algorithm using Sommers duality.

2606.11789 2026-06-11 cs.DB 新提交

Efficient Graph Indexing for Interval-Aware Vector Search

面向区间感知向量搜索的高效图索引

Siyuan Liang, Ziqi Yin, Qi Zhang, Ronghua Li, Guoren Wang, Kaiwen Xue, Daiyin Wang, Xubin Li

AI总结 提出统一区间感知相对邻域图(URNG),支持多种区间感知ANN查询语义,并开发实用图索引UG,通过统一剪枝和迭代修复实现高效搜索。

Comments 14 pages, 13 figures. Preprint version

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AI中文摘要

区间感知近似最近邻(ANN)搜索出现在每个对象关联一个数值或区间的应用中,查询必须同时满足向量相似性和区间约束。现有方法通常针对单一查询语义(如区间过滤ANN搜索)定制,因此需要多个专用索引来支持多样化工作负载,导致大量索引和内存开销。为解决这一限制,我们提出了统一区间感知相对邻域图(URNG),一种用于区间感知ANN搜索的统一图框架。URNG保留了基于相对邻域图的ANN索引的单调可搜索性,同时额外确保查询诱导子图上的结构遗传性,使得单个索引能够支持多种区间感知查询语义。在此框架基础上,我们开发了UG,一种实用的图索引,通过统一区间感知剪枝和迭代修复高效近似URNG,以及用于区间感知ANN搜索的查询算法。在5个数据集上的大量实验表明,UG在多样化的区间感知工作负载中始终实现强精度-效率权衡,同时保持有竞争力的索引构建成本和内存使用。

英文摘要

Interval-aware Approximate Nearest Neighbor (ANN) search arises in applications where each object is associated with a numeric value or interval, and queries must satisfy both vector-similarity and interval constraints. Existing methods are typically tailored to a single query semantics, such as interval-filtered ANN search, and therefore require multiple specialized indexes to support diverse workloads, leading to substantial indexing and memory overhead. To address this limitation, we propose the Unified Interval-aware Relative Neighborhood Graph (URNG), a unified graph framework for interval-aware ANN search. URNG preserves the monotonic searchability of relative-neighborhood-graph based ANN indexes while additionally ensuring structural heredity over query-induced subgraphs, enabling a single index to support multiple interval-aware query semantics. Building on this framework, we develop UG, a practical graph index that efficiently approximates URNG through unified interval-aware pruning and iterative repair, together with a query algorithm for interval-aware ANN search. Extensive experiments on 5 datasets show that UG consistently achieves a strong accuracy-efficiency trade-off across diverse interval-aware workloads while maintaining competitive index construction cost and memory usage.

2606.11788 2026-06-11 astro-ph.HE 新提交

Centrifugal instability of compressible flows and the hydrodynamic stability of accretion disks

可压缩流的离心不稳定性与吸积盘的流体动力学稳定性

Serguei S. Komissarov, Konstantinos N. Gourgouliatos

AI总结 通过推广Rayleigh准则至可压缩流,发现离心不稳定性受马赫数显著影响,数值模拟验证了新准则;分析绕中心致密天体旋转流的稳定性,推导出等价于Solberg-Høiland准则的不稳定判据。

Comments Accepted for publication in MNRAS

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AI中文摘要

最近对压力支撑的可压缩相对论旋转情况下的离心不稳定性分析,应用于天体物理喷流,得到了牛顿流著名Rayleigh准则的推广。根据该准则,离心不稳定性受流动马赫数的强烈影响,不仅在相对论流体动力学中,在其牛顿极限中也是如此。为了验证该准则的牛顿版本,我们对非相对论跨声速旋转流进行了轴对称数值模拟,这些流动根据原始Rayleigh准则是稳定的,但根据新准则可以是稳定或不稳定的。计算机模拟结果与理论完美吻合。吸积盘的流体动力学稳定性通常通过引用原始Rayleigh准则来解释,即使它们的旋转是高度超音速的。为了澄清这个问题,我们分析了绕中心致密天体旋转流的流体动力学稳定性,并推导出一个保留对流动马赫数显式依赖的不稳定准则。该准则等价于标准的Solberg-Høiland准则,后者不涉及马赫数。同样的情况适用于压力支撑旋转,其中离心力扮演重力的角色。

英文摘要

A recent analysis of the centrifugal instability in the case of pressure-supported compressible relativistic rotation, with application to astrophysical jets, yielded a generalisation of the famous Rayleigh criterion for Newtonian flows. According to this criterion, the centrifugal instability is strongly affected by the flow Mach number, and not only in the relativistic fluid dynamics but also in its Newtonian limit. To validate the Newtonian version of this criterion, we performed axisymmetric numerical simulations of non-relativistic transonic rotating flows which are stable according to the original Rayleigh criterion but can be either stable or unstable according to the new one. The results of computer simulations are found to be in perfect agreement with the theory. The hydrodynamic stability of accretion disks is often explained by referring to the original Rayleigh criterion, even if their rotation is highly supersonic. To clarify the matter, we analysed the hydrodynamic stability of flows rotating about central compact object and derived an instability criterion that retains the explicit dependence on the flow Mach number. This criterion turns out to be equivalent to the standard Solberg-Høiland criterion, which does not involve the Mach number. The same applies to the case of pressure-supported rotation, where the role of gravity is played by the centrifugal force.

2606.11787 2026-06-11 math.AP 新提交

Dirichlet eigenfunctions have non-zero mean for generic domains

Dirichlet特征函数在一般域上具有非零均值

Vincent Boulard

AI总结 证明在Baire范畴意义下,一般域上的Dirichlet-Laplacian特征函数均非零均值,通过形状导数退化和Baire范畴论证绕过Schiffer型超定问题,并得到热方程近似可控和快速镇定的推论。

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AI中文摘要

设 $D \subset \mathbb{R}^d$ ($d \geq 2$) 为 $C^m$ 类有界连通开集,$m \geq 3$。我们证明,对于Micheletti拓扑下Baire范畴意义下的一般域 $\Omega \in \mathcal{O}^m(D)$,每个Dirichlet-Laplacian特征函数具有非零均值,即对所有 $n \geq 1$ 有 $\int_\Omega \varphi_n \neq 0$。这回答了Steinerberger和Venkatraman提出的问题。证明基于形状导数计算,其退化性被识别为Schiffer型超定椭圆问题。我们并未解决该问题,而是通过基于解析边界域的贫瘠性的Baire范畴论证绕过它。作为推论,我们得到对于一般域,Dirichlet热方程是近似可控且快速可镇定的,即通过单个空间齐次标量控制,以任意指定的指数衰减率镇定,依据Fattorini-Hautus准则。

英文摘要

Let $D \subset \mathbb{R}^d$ ($d \geq 2$) be a bounded connected open set of class $C^m$ with $m \geq 3$. We prove that, for a generic domain $Ω\in \mathcal{O}^m(D)$ in the sense of Baire category for the Micheletti topology, every Dirichlet-Laplacian eigenfunction has nonzero mean, $\int_Ωφ_n \neq 0$ for all $n \geq 1$. This answers a question raised by Steinerberger and Venkatraman. The proof rests on a shape-derivative computation whose degeneracy is identified with an overdetermined elliptic problem of Schiffer type. Rather than resolving this problem, we bypass it through a Baire-category argument based on the meagerness of domains with analytic boundary. As a consequence, we obtain that for a generic domain the Dirichlet heat equation is approximately controllable, and rapidly stabilizable, i.e. stabilizable at any prescribed exponential decay rate, by a single spatially homogeneous scalar control, via the Fattorini-Hautus criterion.

2606.11785 2026-06-11 math-ph math.MP 新提交

Kohn-Sham models for encapsulated two-dimensional materials

封装二维材料的Kohn-Sham模型

Éric Cancès, David Gontier, Solal Perrin-Roussel

AI总结 研究平行导电电极间封装二维材料的Kohn-Sham DFT模型,证明周期和准周期材料中模型适定性。

Comments 32 pages

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AI中文摘要

我们研究描述置于三维环境中、封装在两个平行导电电极之间的二维材料电子结构的Kohn-Sham密度泛函理论(DFT)模型。在这种几何结构中,电极处的狄利克雷边界条件屏蔽了库仑相互作用,使其变为有效的短程Yukawa型。我们证明了一些非线性Kohn-Sham DFT模型在此设定下是适定的,既适用于周期性材料(如石墨烯),也适用于准周期性材料(如扭曲双层石墨烯和其他莫尔材料,对于一般的不可公度扭转角)。

英文摘要

We study Kohn-Sham Density Functional Theory (DFT) models describing the electronic structure of two-dimensional materials placed in a three-dimensional environment, encapsulated between two parallel conducting electrodes. In this geometry, the Dirichlet boundary conditions at the electrodes screen the Coulomb interaction, which becomes effectively short-ranged, of Yukawa type. We prove that some nonlinear Kohn-Sham DFT models are well-posed in this setting, both for periodic materials (such as graphene) and for quasi-periodic materials (such as twisted bilayer graphene and other moiré materials for generic incommensurate twist angles).

2606.11784 2026-06-11 quant-ph 新提交

Enhancing Many-Body Chaos via Entropy Injection from Environment

通过环境熵注入增强多体混沌

Yuke Zhang, Wenbo Zhou, Pengfei Zhang

AI总结 通过将系统耦合到熵库驱动非平衡态,利用熵注入扩大有效希尔伯特空间,从而增强多体混沌,并用可解布朗SYK模型解析验证。

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AI中文摘要

在封闭量子系统中,局域信息在幺正演化下扩散到整个系统并变得高度复杂。相反,当系统嵌入环境时,系统-环境耦合可以将信息从系统转移到环境中,从而降低系统内复杂性的增长速度。这导致了先前工作中建立的环境诱导的置乱转变。在这项工作中,我们识别出环境熵注入是一种不同的物理过程,它反而增强了多体混沌。我们的设置包括将一个已经与环境平衡的系统耦合到另一个环境,该环境作为熵库并将系统驱动到非平衡态。当熵通过热传递或粒子传递流入系统时,系统探索的有效希尔伯特空间扩大,这是一种可以增强多体混沌的机制。我们通过构建一个可解的复杂布朗SYK模型明确展示了这一想法,在该模型中,向稳态的弛豫和稳态量子李雅普诺夫指数都可以解析计算。我们的结果为通过量子多体系统中与环境耦合的熵流来调节量子置乱提供了一种可控机制。

英文摘要

In closed quantum systems, local information spreads throughout the entire system and becomes highly complex under unitary evolution. In contrast, when the system is embedded in an environment, system-environment coupling can transfer information from the system into the environment, thereby reducing the rate of complexity growth within the system. This leads to the environment-induced scrambling transition established in previous works. In this work, we identify entropy injection from the environment as a different physical process that instead enhances many-body chaos. Our setup consists of coupling a system that is already in equilibrium with one environment to another environment, which serves as an entropy reservoir and drives the system into a non-equilibrium state. When entropy flows into the system through either heat transfer or particle transfer, the effective Hilbert space explored by the system enlarges, a mechanism that can enhance many-body chaos. We explicitly demonstrate this idea by constructing a solvable complex Brownian SYK model, in which both the relaxation toward the steady state and the steady-state quantum Lyapunov exponent can be computed analytically. Our results provide a controllable mechanism for tuning quantum scrambling through entropy flow in quantum many-body systems coupled to environments.

2606.11781 2026-06-11 physics.flu-dyn 新提交

Self-Excited Dynamo Driven by Non-Rotating Laminar Thermal Convection in a Regular Tetrahedron

正四面体中非旋转层流热对流驱动的自激发发电机

Akira Kageyama

AI总结 提出一个无旋转的磁流体发电机模型,利用正四面体腔的几何约束产生螺旋度,通过数值模拟展示磁场指数增长及饱和态,磁能超过动能,流场和磁场具有D4对称性。

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AI中文摘要

我们提出了一个最小化的无旋转磁流体发电机模型,由正四面体腔中的层流热对流驱动。与经典的行星发电机设置不同,后者通过整体旋转提供流动螺旋度,本系统纯粹通过四面体边界施加的几何约束产生稳健的流动螺旋度。直接数值模拟显示,弱种子磁场呈指数放大,并达到非线性饱和态,其中磁能超过动能。对流流场组织成具有\\(D_4\\)二面体对称性的高度对称模式。发电机产生的磁场服从相应的有符号\\(D_4\\)对称性,包括关于四面体两个水平轴的\\(\pi\\)旋转反对称性。四面体发电机为在非旋转层流中分离几何诱导的螺旋度、磁场放大和闭合感应循环提供了一个概念上透明的设置。

英文摘要

We propose a minimal, rotation-free model of magnetohydrodynamic (MHD) dynamo action driven by laminar thermal convection in a regular tetrahedral cavity. Unlike canonical planetary-dynamo settings, where flow helicity is supplied by global rotation, the present system generates robust flow helicity purely through the geometric constraints imposed by tetrahedral boundaries. Direct numerical simulations show exponential amplification of a weak seed magnetic field and a nonlinear saturated state in which the magnetic energy exceeds the kinetic energy. The convective flow organizes into a highly symmetric pattern with \(D_4\) dihedral symmetry. The dynamo-generated magnetic field obeys a corresponding signed \(D_4\) symmetry involving antisymmetry under \(π\)-rotations about the two horizontal axes of the tetrahedron. The tetrahedral dynamo provides a conceptually transparent setting for isolating geometry-induced helicity, magnetic-field amplification, and a closed induction cycle in a non-rotating laminar flow.

2606.11778 2026-06-11 cs.DC 新提交

Consensus Time in 3-Majority and 2-Choices Is Determined by the Maximum Initial Opinion Density

3-Majority 和 2-Choices 中的共识时间由最大初始意见密度决定

Niccolò D Archivio

AI总结 研究同步模型下完全图上3-Majority和2-Choices动态的共识时间,发现其由最大初始意见密度决定,并给出紧界。

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AI中文摘要

我们建立了同步模型下完全图上3-Majority和2-Choices动态收敛时间的正确参数。最近的工作[Shimizu and Shiraga, PODC'25]给出了共识轮次匹配的上下界,但仅在弱意义上:这些界对于某些初始意见配置是一致的。相比之下,我们在强意义上获得了紧界,对于每个初始配置,上下界匹配到对数因子。设$\alpha(0)$为初始意见频率向量,并记$\\|\alpha(0)\\|_\infty$为其最大条目。我们证明,3-Majority以高概率在$\Theta(\min\{\\|\alpha(0)\\|_\infty^{-1}, \sqrt{n}\})$轮内达成共识,而2-Choices以高概率在$\Theta(\\|\alpha(0)\\|_\infty^{-1})$轮内达成共识。我们的结果表明,两种动态的收敛时间不是由全局参数(如意见数量k或初始意见分布的平方$\ell_2$范数)决定,而是由“局部”参数$\\|\alpha(0)\\|_\infty$(最大初始意见密度)决定。

英文摘要

We establish the correct parameter governing the convergence time of the 3-Majority and 2-Choices dynamics on the complete graph in the synchronous model. Recent work [Shimizu and Shiraga, PODC'25] provides matching upper and lower bounds on the number of rounds to consensus, but only in a weak sense: the bounds are shown to coincide for some initial opinion configuration. In contrast, we obtain tight bounds in a strong sense, with upper and lower bounds matching up to logarithmic factors for every initial configuration. Let $α$ (0) be the initial opinion-frequency vector, and denote by ___$α$ (0) ___ $\infty$ its maximum entry. We show that 3-Majority reaches consensus in $Θ$(min{___$α$ (0) ___ -1 $\infty$ , $\sqrt$ n}) rounds w.h.p., while 2-Choices reaches consensus in $Θ$(___$α$ (0) ___ -1 $\infty$ ) rounds w.h.p. Our results demonstrate that the convergence time of both dynamics is governed not by global parameters such as the number of opinions k or the squared ${\ell}$ 2 norm of the initial opinion distribution, but rather by the ''local'' parameter ___$α$ (0) ___ $\infty$ , the maximum initial opinion density.

2606.11777 2026-06-11 cond-mat.mes-hall 新提交

Berry-phase-based Topological Charge in Quasicrystals and their Observable Features in Photonic System

基于Berry相的准晶拓扑电荷及其在光子系统中的可观测特征

Ziyi Chen, Jinyu Zou, Jinhua Gao, Gang xu

AI总结 本文通过群表示论推导准晶中允许的拓扑电荷,建立二维准晶中基于Berry相的拓扑电荷普适框架,以C8v准晶为例展示C=4的高阶拓扑电荷,并在光子准晶中揭示光子动量绕电荷旋转导致电磁场分布模式C次缠绕的可观测特征。

Comments 8 pages, 3 figures

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AI中文摘要

基于Berry相的拓扑电荷在拓扑物理学中起着基础性作用。然而,这类拓扑电荷在准晶中尚未被探索,阻碍了对此类准周期系统中拓扑态的系统理解。在本工作中,通过根据群表示论推导所有允许的拓扑电荷及相应的低能有效哈密顿量,我们建立了二维准晶中基于Berry相的拓扑电荷的普适框架。以$C_{8v}$准晶为例,我们展示并表征了传统周期系统中无法实现的高阶拓扑电荷$C=4$。将我们的框架应用于光子准晶,我们发现光子动量绕电荷的旋转给出了电磁场分布模式的$C$次缠绕。这种可观测特征为探测拓扑电荷提供了直接的实验方法。我们的工作为探索准周期物质中的拓扑电荷铺平了道路,并在根本上连接了周期性和准周期性拓扑能带理论。

英文摘要

Topological charges based on Berry phase play the fundamental role in the topological physics. However, such topological charges remain unexplored in quasicrystals, impeding the systematic understanding of topological states in such quasiperiodic systems. In this work, by deriving all the allowed topological charges according to group representation theory and the corresponding low-energy effective Hamiltonians, we establish a universal framework for Berry-phase-based topological charges in two-dimensional quasicrystals. Taking the $C_{8v}$ quasicrystal as an example, we demonstrate and characterize a higher topological charge of $C=4$, which is inaccessible in conventional periodic systems. Applying our framework to photonic quasicrystals, we uncover that the circling of photon momentum around the charge gives a $C$ times winding of the electromagnetic field distribution pattern. Such observable feature provides a direct experimental method to probe the topological charges. Our work paves the way for exploring topological charges in quasiperiodic matter, and fundamentally bridges periodic and quasiperiodic topological band theories.

2606.11776 2026-06-11 math.CO math.RT 新提交

Special Matchings, Brenti's Conjecture, and the Combinatorial Invariance Conjecture

特殊匹配、Brenti猜想与组合不变性猜想

Fabrizio Caselli, Mario Marietti

AI总结 本文完全刻画了A型Coxeter群中任意Bruhat区间的特殊匹配,并应用此结果证明了Brenti关于通过特殊匹配计算Kazhdan-Lusztig R-多项式的猜想,为组合不变性猜想提供了新证据。

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AI中文摘要

在这项工作中,我们解决了一个可追溯到21世纪初的问题。我们给出了$A$型Coxeter群中任意Bruhat区间的特殊匹配的完整刻画,并将这一结果应用于证明Brenti在2003年提出的关于通过特殊匹配计算Kazhdan-Lusztig $R$-多项式的猜想。这为组合不变性猜想提供了新的证据。

英文摘要

In this work, we settle a problem that dates back to the early 2000s. We provide a complete characterization of special matchings of arbitrary Bruhat intervals in Coxeter groups of type $A$ and apply this result to prove a conjecture of Brenti from 2003 concerning the computation of Kazhdan-Lusztig $R$-polynomials via special matchings. This yields new evidence in support of the Combinatorial Invariance Conjecture.

2606.11775 2026-06-11 math.MG q-bio.QM stat.ML 新提交

Magnitude-Based Features for Multispecies Spatial Data

基于量值的多物种空间数据特征

Julia Sollberger, Joshua Bull, Sara Kališnik, Bernadette Stolz

AI总结 提出基于量值的全局和局部特征向量,用于分析多物种空间数据中的相互作用,在合成肿瘤微环境和人类结直肠癌组织微阵列数据中验证了其识别空间异质性和分类能力。

Comments 32 pages, 24 figures

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AI中文摘要

多物种空间数据出现在许多应用中,其中不同实体之间的相互作用对系统行为至关重要,包括生物医学成像、地理空间分析和物种生态学。尽管它们很重要,但捕获这种相互作用的定量工具相对较少。在这项工作中,我们提出了基于量值的特征用于分析多物种空间数据。量值是有限度量空间的一个实值不变量,可以解释为有效点数,结合了空间配置和尺度。我们开发了全局和局部量值特征向量,并在合成肿瘤微环境数据以及人类结直肠癌样本的组织微阵列数据中展示了它们的实用性。在局部,该方法识别出不同的邻域类型并揭示空间异质性;在模型中,这包括与模拟的不同定性结果相关的径向模式,而在真实世界数据中,它反映了B细胞和T细胞群体之间三级淋巴结构样相互作用的重要性。在全局上,该方法恢复了合成数据中跨参数区域的长期模拟结果的已知分类,并提示CD4+ T细胞和CD163+巨噬细胞在区分有利的克罗恩样反应与不利的弥漫性免疫浸润患者中发挥重要作用。总之,这些结果表明基于量值的特征为多物种空间数据分析提供了强大而灵活的工具。

英文摘要

Multispecies spatial data arise in many applications where interactions between different entities are central to system behaviour, including biomedical imaging, geospatial analysis, and species ecology. Despite their importance, relatively few quantitative tools exist to capture such interactions. In this work, we propose magnitude-based features for the analysis of multispecies spatial data. Magnitude is a real-valued invariant of finite metric spaces that can be interpreted as an effective number of points, incorporating both spatial configuration and scale. We develop global and local magnitude feature vectors and demonstrate their utility on synthetic tumour microenvironment data, and in tissue microarray data from human colorectal cancer samples. Locally, the method identifies distinct neighbourhood types and reveals spatial heterogeneity; in the model, this includes radial patterns associated with different qualitative outcomes of the simulations, while in the real-world data it reflects the importance of tertiary lymphoid structure-like interactions between B and T cell populations. Globally, the approach recovers known classifications of long-term simulation outcomes across parameter regimes in synthetic data, and suggests important roles for CD4+ T cells and CD163+ macrophages in distinguishing patients with favourable Crohn's like reactions from unfavourable diffuse immune infiltration. Together, these results suggest that magnitude-based features provide a powerful and flexible tool for the analysis of multispecies spatial data.

2606.11774 2026-06-11 math.PR math.AP 新提交

Martingale Solutions to a Stochastic Keller-Segel System with nonlocal Source and Super-linear Noise

具有非局部源和超线性噪声的随机Keller-Segel系统的鞅解

Qian Li, Li Chen, Jinhuan Wang

AI总结 针对具有非局部Fisher-KPP源和超线性乘性噪声的随机Keller-Segel系统,在非局部源项占优且初始数据非负无小量假设下,通过改进的Galerkin方法和紧性论证证明了全局非负鞅解的存在性。

Comments 41 pages

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AI中文摘要

对于具有非局部Fisher-KPP源和超线性乘性噪声的随机Keller-Segel系统,证明了全局非负鞅解的存在性。该结果在非局部源项占优的条件下,对非负初始数据无需小量假设。主要困难源于缺乏强制性结构和噪声的超线性性质。在经典Galerkin方法中添加了具有有限L^2范数的额外截断,以建立适定的逼近问题。此外,由于非局部Fisher-KPP结构,需要证明逼近解的正性以获得一致估计。在紧性论证中,希尔伯特空间框架下的通常紧性论证无法直接应用于本文获得的一致估计。因此,我们开发了更一般的紧性论证和紧性准则(见附录),并在全文应用。这使得通过Jakubowski版本的Skorokhod定理以及收敛性质的详细讨论,能够推导出全局非负鞅解的存在性。

英文摘要

Global nonnegative martingale solutions are shown to exist for a stochastic Keller-Segel system with a nonlocal Fisher-KPP source and super-linear multiplicative noise. The result is obtained for nonnegative initial data with no smallness assumption, provided that the nonlocal source term is dominant. The main difficulty stems from the absence of a coercive structure and the super-linear nature of the noise. An additional cut-off with finite L^2 norm in the classical Galerkin method is added to establish a well-posed approximation problem. Moreover, due to the nonlocal Fisher-KPP structure, it is necessary to prove the positivity of the approximating solution in order to obtain uniform estimates. In the compactness arguments, the usual tightness argument in the framework of Hilbert spaces cannot be directly applied to the uniform estimates obtained in this paper. As a result, we develop a more general version of the compactness argument and tightness criterion, presented in the appendix, which will be applied throughout the paper. This allows for the global existence of nonnegative martingale solutions to be derived from Jakubowski's version of the Skorokhod Theorem, along with a thorough discussion of the convergence properties.

2606.11772 2026-06-11 math.NA cs.NA math-ph math.DG math.MP 新提交

Curvature-Induced Force Fields in Hyperelasticity

超弹性中的曲率诱导力场

Victor Dods

AI总结 针对二维旋转曲面中平坦超弹性体的嵌入问题,通过变分法数值模拟静态平衡,揭示曲率梯度诱导的恢复力与引力平衡导致的“悬浮”现象。

Comments 31 pages. 13 figures. Accepted for publication in Contemporary Mathematics (AMS). All code and data is available at https://github.com/vdods/jello

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AI中文摘要

最初出于在黎曼流形中创建第一人称计算机可视化的动机,作者开始研究可变形体力学,因为在一般黎曼流形中,由于缺乏非平凡等距群,刚体力学不可用。超弹性是连续介质力学中一个特别好的子类别,其中可变形弹性体的行为由存储能量密度函数决定。这使得问题可以变分地提出,并利用强大的工具来研究和求解。本文展示了二维黎曼流形中一类特定超弹性力学问题的静态解的数值模拟,其中平坦超弹性体$B$被嵌入到无平坦旋转曲面$S: z=z(r)$的区域$\Omega$中,使得$|K(r)|$随$r\to\infty$递减,其中$K$表示$S$的高斯曲率。例如,漏斗$z=-r^{-1}$或抛物面$z=\frac{1}{2}r^2$。由于$B$是平坦的,该体无法达到零存储能量构型,因此体内产生恢复力将其移向较低存储能量的区域——即更平坦的构型。在$S$上添加引力势$U(r)=z(r)$后,力作用于该体将其拉向$r=0$。如果该体具有足够的刚度并保持在区域$\Omega$内,则该体存在一个平衡构型,其中体的变形响应力完美抵消引力。这种构型代表了该曲面内的一种“悬浮”现象。本文将详细阐述该问题的数值实现,并讨论所得的数值解及各种推论。

英文摘要

Originally motivated by creating first-person computer visualizations within Riemannian manifolds -- the author was led to study deformable-body mechanics, as rigid-body mechanics is not available in a generic Riemannian manifold due to its lack of nontrivial isometry group. Hyperelasticity is a particularly nice sub-category of continuum mechanics in which a deformable, elastic body's behavior is determined by a stored energy density function. This allows problems to be posed variationally, and powerful tools brought to bear on studying and solving them. This article presents numerical simulations of static solutions to a particular class of problems in hyperelastic mechanics in 2-dimensional Riemannian manifolds in which a flat hyperelastic body $B$ is embedded into a region $Ω$ in a nowhere-flat surface $S$ of revolution $z=z\left(r\right)$ such that $\left|K\left(r\right)\right|$ decreases as $r\to\infty$, where $K$ denotes the Gaussian curvature of $S$. For example, the funnel $z=-r^{-1}$ or the paraboloid $z=\frac{1}{2}r^{2}$. Because $B$ is flat, the body can't achieve a zero-stored-energy configuration, and restorative forces arise in the body to move it toward a region of lower stored energy -- meaning, toward a flatter configuration. With the addition of a gravitational potential $U\left(r\right)=z\left(r\right)$ on $S$, forces act on the body to pull it toward $r=0$. If the body has sufficient stiffness and remains within the region $Ω$, then the body has an equilibrium configuration in which the body's deformation-response forces perfectly cancel the gravitational forces. Such a configuration represents a kind of "levitation" phenomenon within this surface. The numerical implementation of this problem will be detailed and the resulting numerical solutions and various consequences discussed.

2606.11771 2026-06-11 cs.IT math.IT 新提交

Segment-Wise Soft Robotics Inspired Flexible Antenna Arrays: Design and Optimization

分段式软体机器人柔性天线阵列:设计与优化

Shuaishuai Han, Konstantinos Ntougias, Elio Faddoul, Ioannis Krikidis

AI总结 提出分段式软体机器人天线系统,通过独立控制分段运动实现天线位置重构,并设计两种部署方案及优化算法,显著提升和速率。

Comments Summitted to IEEE transaction journal

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AI中文摘要

本文提出了一种分段式软体机器人天线(SRA)系统,其中每个软体机械臂(称为触手)包含多个独立可控的分段,具有弯曲、伸缩和扫掠运动。通过调整分段运动参数,表面安装天线的位置得以重构,这使其区别于传统的可重构天线(RA)系统。基于该模型,我们提出了两种天线部署方案:分段端天线配置(SEAC),其中固定天线安装在分段末端并通过分段运动重构;以及混合端与中间天线配置(HEIAC),其中RA进一步集成作为分段内天线。在HEIAC中,软体机器人分段变形提供大规模空间重构,而RA实现精细调整。对于SEAC,我们建立了一个考虑分段间连通性和从分段变形参数到天线坐标非线性映射的和速率最大化问题,并开发了罚对偶分解-投影梯度上升(PDD-PGA)算法。对于HEIAC,我们使用块坐标下降(BCD)-PDD-PGA算法联合优化分段变形、分段内天线位置和天线激活,并采用贪心反向天线选择。仿真结果表明,所提方案显著优于固定位置天线阵列和传统RA基线。特别地,SEAC和HEIAC相比传统3D可重构阵列分别实现了37.9%和32.1%的和速率增益,而SEAC在紧凑阵列部署中提供了高达49.3%的增益。

英文摘要

In this paper, we propose a segment-wise soft robotic antenna (SRA) system, where each soft robotic arm referred to as a tentacle, comprises multiple independently controllable segments with bending, elongation-retraction, and sweeping motions. By adjusting segment motion parameters, the positions of surface-mounted antennas are reconfigured, distinguishing it from conventional reconfigurable antenna (RA) systems. Based on this model, we propose two antenna deployment schemes: the segmented end-antenna configuration (SEAC), where fixed antennas are mounted at the segment ends and reconfigured via segment motions; and the hybrid end-and-intermediate antenna configuration (HEIAC), where RAs are further integrated as intra-segment antennas. In HEIAC, soft-robot segment deformation provides large-scale spatial reconfiguration, while RAs enable fine-grained adjustment. For SEAC, we formulate a sum-rate maximization problem accounting for inter-segment connectivity and the nonlinear mapping from segment deformation parameters to antenna coordinates, and develop a penalty dual decomposition-projected gradient ascent (PDD-PGA) algorithm. For HEIAC, we jointly optimize segment deformation, intra-segment antenna positions, and antenna activation using a block coordinate descent (BCD)-PDD-PGA algorithm with greedy backward antenna selection. Simulation results demonstrate that the proposed schemes substantially outperform fixed-position antenna arrays and conventional RA baselines. In particular, SEAC and HEIAC achieve 37.9% and 32.1% sum-rate gains over conventional 3D reconfigurable arrays, respectively, while SEAC provides up to a 49.3% gain in compact array deployments.

2606.11768 2026-06-11 stat.ME stat.AP 新提交

Hierarchical excitatory processes for modelling event-time data in the presence of exogenous stimuli

外源刺激下事件时间数据建模的分层激发过程

Francesco Sanna Passino, Nicholas A. Heard, Jeffrey W. Brown, William N. Frost, Vince P. Lyzinski

AI总结 提出分层激发过程(HEP)模型,通过动态演化核函数叠加外源刺激的激发效应,实现对重复刺激下事件时间数据的灵活建模,并嵌入聚类框架识别潜在响应模式。

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AI中文摘要

我们引入了分层激发过程(HEP),一种用于在重复外部刺激下观察到的事件时间数据的灵活点过程模型。所提出的框架将点过程的条件强度建模为外部刺激引起的激发效应的叠加,其特征由参数随时间动态演化的核函数刻画。这种分层结构使得能够跨重复刺激调节激发强度,提供了一种可解释的结构。我们为所提出的模型建立了基于似然的推断,并将HEP嵌入到基于模型的聚类框架中,以识别具有相似响应动态的潜在组。模拟研究证明了该模型恢复演化潜在模式的能力,而对海蛞蝓足神经节尖峰序列记录的应用展示了HEP如何能够在不同实验条件下表征重复刺激下神经元的刺激驱动兴奋性。

英文摘要

We introduce the Hierarchical Excitatory Process (HEP), a flexible point process model for event-time data observed under repeated external stimuli. The proposed framework models the conditional intensity of a point process as a superposition of excitation effects induced by external stimuli, characterised by kernels with parameters dynamically evolving over time. This hierarchical construction enables modulation of excitation strength across repeated stimuli, providing an interpretable structure. We establish likelihood-based inference for the proposed model and embed HEP within a model-based clustering framework to identify latent groups sharing similar response dynamics. Simulation studies demonstrate the model's ability to recover evolving latent patterns, and an application to spike train recordings from the sea slug Aplysia pedal ganglion illustrates how HEPs are able to characterise stimulus-driven excitability of neurons across repeated stimulation under different experimental conditions.

2606.11765 2026-06-11 cond-mat.stat-mech 新提交

A stochastic model for elastoplastic contact of rough surfaces incorporating scale-dependent hardness

包含尺度相关硬度的粗糙表面弹塑性接触的随机模型

Yang Xu, Hengxu Song, Jianqiao Hu

AI总结 提出基于复合Chapman-Kolmogorov方程的随机方法,首次求解尺度相关硬度的弹塑性接触问题,推导新地形屈服参数并实现接触状态快速识别。

Comments 38 pages, 13 figures

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AI中文摘要

天然和制造表面固有粗糙度引起的应力集中常导致接触界面发生塑性变形,而塑性变形的尺寸效应与自仿射粗糙表面形貌的竞争影响使这一问题更加复杂。为此,我们基于随机理论,首次采用复合Chapman-Kolmogorov方程开发了一种新方法,用于求解涉及尺度相关硬度的弹塑性接触问题。我们的方法构建了三个积分方程,描述弹性接触压力、相对塑性接触面积和相对非接触面积的概率密度函数随几何尺度的演化。我们深入研究了尺度相关硬度对接触压力分布、相对弹性和塑性接触面积以及面积-载荷关系的影响。通过调整各种力学和材料属性,我们的模型预测了从线弹性到弹塑性行为,最终到完全塑性的平滑过渡。一个关键进展是推导了一个新的地形屈服参数,该参数包含了更广泛的材料和几何属性,有助于识别接触状态。数值解通过曲线拟合能够高精度地确定弹性和塑性极限,我们还提供了一个新的图表用于快速识别接触状态。本研究开创了将复合Chapman-Kolmogorov方程应用于粗糙表面接触分析的随机过程框架,而描述界面属性随尺度演化的积分方程可为其他多尺度粗糙度至关重要的多学科领域(如地震、电接触和接触起电)提供有价值的见解。

英文摘要

The stress concentrations caused by inherent roughness of natural and manufactured surfaces often induce plastic deformation at contact interfaces, a challenge compounded by competing influences of the size effect of plastic deformation and self-affine rough surface topography. To address this, we developed a novel methodology based on stochastic theory using compounded Chapman-Kolmogorov equations, for the first time, to solve elastoplastic contact problems involving scale-dependent hardness. Our approach formulates three integral equations describing the evolution of probability density functions of elastic contact pressure, relative plastic contact area, and relative non-contact area across geometrical scales. We thoroughly investigate the effects of scale-dependent hardness on contact pressure distribution, relative elastic and plastic contact areas, and the area-to-load relationship. By adjusting various mechanical and material properties, our model predicts a smooth transition from linear elasticity to elastic-plastic behavior and finally to full plasticity. A key advancement is the derivation of a new topographic yield parameter incorporating a wider range of material and geometrical properties, aiding identification of contact status. Numerical solutions enable highly precise determination of elastic and plastic limits via curve-fitting, and we also provide a new diagram for rapid identification of contact status. This study pioneers a stochastic process framework for applying the compounded Chapman-Kolmogorov equation to rough surface contact analysis, and the integral equations characterizing how interfacial properties evolve with scale could offer valuable insights for other multidisciplinary fields where multiscale roughness is critical, such as earthquakes, electrical contact, and contact electrification.

2606.11764 2026-06-11 cs.IT math.IT 新提交

Non-special Divisors, LCPs of Codes, and LCD Codes on Kummer Extensions

库默尔扩张上的非特殊因子、码的线性互补对和LCD码

Huachao Zhang, Chang-An Zhao

AI总结 研究库默尔扩张上非特殊因子的算术刻画,基于此在GK曲线上构造度g-1的非特殊因子,并利用纯间隙构造度g的有效非特殊因子族,进而建立代数几何码的LCP和LCD码的通用框架。

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AI中文摘要

近年来,由于线性互补对(LCP)和线性互补对偶(LCD)码的广泛应用,基于函数域的这些码的构造引起了广泛关注。这类构造依赖于度$g$和$g-1$的非特殊因子。本文研究了由$y^m = f(x)$(其中$f(x)\in\mathbb{F}_q(x)$)定义的库默尔扩张,并建立了非特殊因子的算术刻画,其支撑可以包含非完全分歧位点。基于这一刻画,我们在GK曲线上显式构造了度$g-1$的非特殊因子。此外,利用纯间隙,我们在库默尔扩张上显式构造了几个具有相同重数的度$g$的有效非特殊因子族。然后,我们开发了一个在库默尔扩张上构造代数几何(AG)码的LCP的通用框架。借助典范因子,我们证明了在该框架内可以确定AG码的LCP的安全参数,这也使得LCD AG码的构造成为可能。最后,我们通过代表性例子展示了结果,包括GK曲线上的LCP码和Hermitian曲线商上的LCD码。

英文摘要

Recently, constructions of linear complementary pairs (LCPs) of codes and linear complementary dual (LCD) codes on function fields have attracted considerable attention due to the wide range of applications of these codes. Such constructions rely on non-special divisors of degrees $g$ and $g-1$. In this work, we investigate Kummer extensions defined by $y^m = f(x)$ with $f(x)\in\mathbb{F}_q(x)$ and establish an arithmetic characterization of non-special divisors whose support can contain non-totally ramified places. Based on this characterization, we explicitly construct non-special divisors of degree $g-1$ on the GK curve. Moreover, utilizing pure gaps, we explicitly provide several families of effective non-special divisors of degree $g$ on Kummer extensions with the same multiplicities. We then develop a general framework for constructing LCPs of algebraic geometry (AG) codes on Kummer extensions. By virtue of canonical divisors, we show that the security parameters of LCPs of AG codes can be determined within this framework, which also enables the construction of LCD AG codes. Finally, we illustrate our results with representative examples, including LCPs of codes on the GK curve and LCD codes on quotients of the Hermitian curve.

2606.11763 2026-06-11 math.CO 新提交

Enumerating inherited conics in André planes of odd order

奇阶André平面中继承圆锥曲线的枚举

S. G. Barwick, Alice M. W. Hui, Wen-Ai Jackson

AI总结 研究奇素数幂阶André平面中,PG(2,q^t)上的圆锥曲线何时继承为弧,并枚举了继承弧的数量。

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AI中文摘要

从Desarguesian平面$PG(2,q^2)$导出Hall平面的过程是众所周知的,并且已经解决了$PG(2,q^2)$中的圆锥曲线何时继承为Hall平面中的弧的问题。本文考虑将André网替换为$PG(2,q^t)$($t\geq 3$)以构造$q^t$阶André平面的推广。本文研究$q$为奇数且$t$为素数的情况,并确定$PG(2,q^t)$中的圆锥曲线何时继承为André平面中的弧。此外,还枚举了以这种方式继承的André平面中的弧的数量。

英文摘要

The process of deriving the Desarguesian plane $PG(2,q^2)$ to get the Hall plane is well known, and the problem of when a conic in $PG(2,q^2)$ inherits to an arc in the Hall plane has been solved. In this article we look at the generalisation of replacing an André net of $PG(2,q^t)$, $t\geq 3$ to construct an André plane of order $q^t$. This article looks at the case where $q$ is odd and $t$ is prime, and determines when a conic in $PG(2,q^t)$ inherits to an arc in an André plane. Further, the number of arcs in an André plane that are inherited in this way is enumerated.

2606.11760 2026-06-11 cs.DS cs.CR cs.DB 新提交

A Fast Gaussian Mechanism under Continual Observation, with Applications

持续观测下的快速高斯机制及其应用

Rasmus Pagh, Sia Sejer

AI总结 针对持续更新场景下的私有向量发布问题,提出一种基于布朗桥的常数时间采样方法,实现高斯噪声的快速生成,并应用于差分隐私计数草图,提升正交范围计数查询和连接大小估计的性能。

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AI中文摘要

我们考虑在更新下私有发布$k$维向量的问题:从零向量开始,在时间$t_1, t_2,\dots$,向量分别加上$x^{(1)}, x^{(2)},\dots$。对于正整数$T, k$,我们将更新建模为数据集$\{(t_i, x^{(i)})\}_i$,其中$t_i \in [T]$且$x^{(i)} \in B_k$($k$维单位球)。如果两个这样的数据集的对称差大小至多为$1$,则称它们为相邻的。持续发布包括每个时间步$t=1,\dots,T$的和$A^{(t)} = \sum_{i \;: \; t_i \leq t} x^{(i)}$。经典的持续发布技术允许我们以$\text{polylog}(T)$的加性噪声幅度发布$A^{(1)},\dots,A^{(T)}$的近似,计算时间为$O(kT)$,即使在在线自适应情况下(数据持续揭示当前时间步)也是如此。受私有草图技术的启发,我们考虑在时间步$t$仅需发布$A^{(t)}$中条目的\emph{子集}的设置。我们的新结果是,可以在\emph{常数时间}内采样给定噪声向量中的任何所需条目,同时精确再现具有高斯噪声的二叉树机制的分布。对已知$O(\log T)$时间界的改进来自一种新的数据结构,它允许我们使用布朗桥在常数时间内以正确的相关性采样新的噪声值。我们提出了两个独立感兴趣的数据管理应用,它们将我们的技术与差分隐私CountSketch结合使用:1)正交范围计数查询的动态数据结构,具有比先前数据结构更好的隐私/准确性/空间权衡;2)连接大小估计,其中我们还展示了改进的高概率界。

英文摘要

We consider the problem of privately releasing a $k$-dimensional vector under updates: Starting with a zero vector, at times $t_1, t_2,\dots$ the vector is updated by adding $x^{(1)}, x^{(2)},\dots$, respectively. For positive integers $T$, $k$ we model the updates as a data set $\{(t_i, x^{(i)})\}_i$, where $t_i \in [T]$ and $x^{(i)} \in B_k$ (the $k$-dimensional unit ball). Two such data sets are said to be neighboring if their symmetric difference has size at most $1$. The continual release consists of the sum $A^{(t)} = \sum_{i \; : \; t_i \leq t} x^{(i)}$ for each time step $t=1,\dots,T$. Classical continual release techniques allow us to release an approximation of $A^{(1)},\dots,A^{(T)}$ with additive noise of magnitude $\text{polylog}(T)$, computed in time $O(kT)$, even in the on-line, adaptive case where data is continually revealed for the current time step. Motivated by private sketching techniques, we consider the setting where only a \emph{subset} of entries in $A^{(t)}$ need to be released at time step $t$. Our new result is that it is possible to sample any desired entry in a given noise vector in \emph{constant time} while reproducing exactly the distribution of the binary tree mechanism with Gaussian noise. The improvement on the known time bound of $O(\log T)$ comes from a new data structure that allows us to sample a new noise value with the correct correlations in constant time using Brownian bridges. We present two data management applications, of independent interest, that use our technique in conjunction with differentially private CountSketches: 1) A dynamic data structure for orthogonal range counting queries with a better privacy/accuracy/space trade-off than previous data structures, and 2) Join size estimation, where in addition we show improved high-probability bounds.

2606.11759 2026-06-11 quant-ph 新提交

Random Grover Search

随机格罗弗搜索

Dekuan Dong, Jiaxin Ma, Yingzhou Li

AI总结 提出一种随机化Grover搜索算法,直接使用约束预言机而非全局预言机,证明在均匀采样下经Θ(π/4 √(N/r))次迭代成功概率趋近1,达到相同渐近查询复杂度。

Comments 23 pages, 5 figures

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AI中文摘要

Grover算法在给定目标集的全局预言机的情况下,对非结构化搜索实现了二次加速。然而,在许多应用中,目标集被指定为多个约束集的交集。构建交集的全局预言机代价高昂,而单个约束预言机通常更容易实现。我们研究了一种直接使用这些约束预言机的随机化Grover搜索算法。在每次迭代中,随机选择对应的Grover算子之一。对于均匀采样的两算子情况,我们证明成功概率在\[ \Theta \left(\frac\pi4\sqrt{\frac{N}{r}}\right) \]次迭代后趋近于1,其中$r$是交集的大小。因此,该算法实现了与标准Grover搜索相同的渐近查询复杂度,但不需要全局预言机。然后,我们通过一个近似期望Grover演化的辅助算子,将分析推广到任意采样分布和任意数量的Grover算子,同时保持相同的渐近复杂度。我们进一步表明,高度偏斜的采样分布仍然可以实现接近单位的成功概率,从而允许更频繁地使用更便宜的Grover算子。最后,我们证明了渐近最优性,并通过数值模拟支持理论结果。

英文摘要

Grover's algorithm achieves a quadratic speedup for unstructured search given a global oracle for the target set. In many applications, however, the target set is specified as the intersection of multiple constraint sets. Constructing a global oracle for the intersection can be costly, whereas the individual constraint oracles are often much simpler to implement. We study a randomized Grover search algorithm that directly uses these constraint oracles. At each iteration, one of the corresponding Grover operators is selected at random. For the two-operator case with uniform sampling, we prove that the success probability approaches one after \[ Θ\left(\frac\pi4\sqrt{\frac{N}{r}}\right) \] iterations, where $r$ is the size of the intersection. Thus, the algorithm achieves the same asymptotic query complexity as standard Grover search but without requiring a global oracle. We then generalize the analysis to arbitrary sampling distributions and an arbitrary number of Grover operators through an auxiliary operator that approximates the expected Grover evolution, while retaining the same asymptotic complexity. We further show that highly biased sampling distributions can still achieve near-unit success probability, enabling cheaper Grover operators to be used more frequently. Finally, we prove asymptotic optimality and support the theoretical results with numerical simulations.

2606.11758 2026-06-11 math.PR 新提交

Exact Fourier dimensions of dyadic Mandelbrot cascades on curves of nonvanishing curvature under minimal integrability

非零曲率曲线上二元曼德博级联在最小可积性下的精确傅里叶维数

Yin Cai, Xiang Fang, Hongdou Qu

AI总结 本文证明了在最小Kahane-Peyriere条件下,标量二元曼德博级联在固定C^2 Jordan曲线(非零曲率)上的推前测度几乎必然具有精确傅里叶维数,等于局部指数A_loc(W)。

Comments 45 pages

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AI中文摘要

我们证明了标量二元曼德博级联在固定C^2 Jordan曲线(非零曲率)上的推前测度的精确傅里叶维数公式。设W处于最小Kahane-Peyriere区间,标量二元级联定义在T = R/Z上,gamma将T映射到R^2,是一条固定C^2 Jordan曲线,具有非零曲率,并以恒定速度参数化。对于推前测度mu_gamma,我们证明,几乎必然在非灭绝条件下,其傅里叶维数为A_loc(W),即通常通过优化q>1从涉及E[W^q]的矩表达式中得到的局部指数。上界来自标量圆局部维数定理、双Lipschitz转移到固定曲线,以及傅里叶维数的确定性弯曲支撑障碍。下界来自固定曲线有限环定理,该定理在单个有限矩见证下给出可加环状傅里叶衰减。主要分析输入是固定非退化C^2曲线的确定性相位几何包:平稳管、导数带和相位箱系数估计,取代了单位圆上可用的显式三角结构。

英文摘要

We prove an exact Fourier-dimension formula for scalar dyadic Mandelbrot cascades pushed forward to fixed C^2 Jordan curves with nonvanishing curvature. Let W be in the minimal Kahane-Peyriere regime, let the scalar dyadic cascade live on T = R/Z, and let gamma map T to R^2 be a fixed C^2 Jordan curve with nonvanishing curvature, parametrized at constant speed. For the push-forward measure mu_gamma, we prove that, almost surely on non-extinction, its Fourier dimension is A_loc(W), the usual local exponent obtained by optimizing over q>1 from the moment expression involving E[W^q]. The upper bound follows from the scalar circle local-dimension theorem, bi-Lipschitz transfer to the fixed curve, and a deterministic curved-support obstruction for Fourier dimension. The lower bound follows from a fixed-curve finite-r annular theorem, which gives summable annular Fourier decay under a single finite moment witness. The main analytic input is a deterministic phase-geometry package for fixed nondegenerate C^2 curves: stationary tubes, derivative bands, and phase-bin coefficient estimates replacing the explicit trigonometric structure available on the unit circle.

2606.11756 2026-06-11 physics.app-ph 新提交

Intercoupling of bulk acoustic streaming and acoustothermal effect: A high-frequency focused beam example

体声流与声热效应的耦合:以高频聚焦波束为例

Shiyu Li, Zhixiong Gong

AI总结 针对高频聚焦声束中声热效应对细胞捕获的影响,提出耦合声传播、体声流和声热效应的理论模型,揭示温度梯度引起的声体力弱于粘性衰减引起的声体力,且热对流可显著降低温升。

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AI中文摘要

高频聚焦声束有望用于流体中细胞的选择性捕获,但相关的声吸收可能产生较大的声热效应,导致细胞或微粒受热,并因热梯度引入额外的声体力。聚焦波束中体声流和声辐射力用于三维选择性捕获细胞的理论已有发展[Li and Gong, Phys. Rev. Fluids, 11, 054201 (2026)],然而,在高频强吸收下声热效应及其对声场的反馈仍知之甚少。为解决此问题,我们开发了一个理论数值模型,耦合了水中的声传播、体声流和声热效应。声体力分解为粘性衰减引起的声体力$\mathbf{f}_{\mathrm{E}}$和温度梯度引起的声体力$\mathbf{f}_{\mathrm{T}}$,而温度场通过温度依赖的材料属性反馈到频域声学计算。以单聚焦波束为例,在机械指数约束的压力范围内,$\mathbf{f}_{\mathrm{T}}$仍弱于$\mathbf{f}_{\mathrm{E}}$,而当热佩克莱特数($Pe_T$)超过1时,流致对流可显著降低温升。本工作为预测和控制高频聚焦波束的体声流与声热效应耦合提供了理论基础,有助于单束声镊的设计。

英文摘要

High-frequency focused acoustic beams are promising for selective trapping of cells in fluids, but the related acoustic absorption may generate large acoustothermal effect which could cause thermal heating on cells or microparticles and bring extra acoustic body force due to the thermal gradient. The theory of the bulk acoustic streaming and acoustic radiation force in a focused-beam for the three-dimensional selective trapping of a cell has been developed [Li and Gong, Phys. Rev. Fluids, 11, 054201 (2026)], however, the acoustothermal effect and its feedback on the acoustic field at high frequency with strong absorption remain weakly understood. To solve this issue, we develop a theoretical and numerical model that couples acoustic propagation, bulk acoustic streaming, and acoustothermal effect in water. The acoustic body force is decomposed into a viscous-attenuation-induced acoustic body force $\mathbf{f}_{\mathrm{E}}$ and a temperature-gradient-induced acoustic body force $\mathbf{f}_{\mathrm{T}}$, while the temperature field is fed back to the frequency-domain acoustic calculation through the temperature-dependent material properties. Taking the single focused beam for example, within the pressure range constrained by the mechanical index, $\mathbf{f}_{\mathrm{T}}$ remains weaker than $\mathbf{f}_{\mathrm{E}}$, whereas streaming-induced convection can markedly reduce the temperature rise when the thermal Peclet number ($Pe_T$) exceeds unity. This work establishes a theoretical basis for predicting and controlling the intercoupling of bulk acoustic streaming and acoustothermal effec of high-frequency focused beams which will be helpful for the design of single-beam acoustical tweezers.

2606.11755 2026-06-11 cs.SE 新提交

Acoda: Adversarial Code Obfuscation for Defending against LLM-based Analysis

Acoda:对抗性代码混淆防御基于LLM的分析

Hongzhou Rao, Zikan Dong, Yanjie Zhao, Haodong Li, Haoyu Wang

AI总结 提出基于遗传算法的对抗性代码混淆框架Acoda,通过8种语义保留的混淆方法迭代优化,有效诱导LLM拒绝或误判代码分析,在7个先进LLM上攻击成功率高达70%。

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AI中文摘要

随着大型语言模型(LLM)在软件工程(SE)任务(如代码理解、调试和漏洞检测)中的广泛采用,其强大的语义推理能力也带来了新的安全和隐私风险。LLM可以分析、重构甚至逆向工程源代码逻辑,可能导致知识产权泄露。为解决这一问题,我们提出了Acoda,一种基于遗传算法的对抗性代码混淆框架,用于防御基于LLM的代码分析。Acoda利用LLM的两个关键机制,即安全对齐和基于令牌的信息处理,设计了8种保留语义的混淆方法。它通过遗传算法迭代优化混淆策略,生成最大化防御效果的对抗样本。此外,我们提出了一种基于LLM响应的定量评估框架,该框架结合辅助LLM和四个评估指标,全面评估目标LLM分析混淆代码的能力。实验结果表明,Acoda能有效诱导LLM拒绝或误判代码分析。在包括GPT-4o、DeepSeek、Qwen、Llama和Gemma在内的7个最先进LLM上,Acoda实现了高达70%的攻击成功率(ASR),具有强大的跨模型迁移性和最小的运行时开销,同时确保原始代码的语义不变。总体而言,本研究为LLM时代的代码保护和LLM安全防御提供了新视角。

英文摘要

With the widespread adoption of Large Language Models (LLMs) in software engineering (SE) tasks such as code understanding, debugging, and vulnerability detection, their powerful semantic reasoning ability has also introduced new security and privacy risks. LLMs can analyze, reconstruct, or even reverse-engineer source code logic, potentially leading to the leakage of intellectual property. To address this issue, we propose Acoda, a genetic algorithm-based adversarial code obfuscation framework that defends against LLM-based code analysis. Acoda leverages two key mechanisms of LLMs, namely safety alignment and token-based information processing, to design 8 semantics-preserving obfuscation methods. It iteratively optimizes obfuscation strategies through a genetic algorithm to generate adversarial samples that maximize defensive effectiveness. In addition, we propose a quantitative evaluation framework based on LLM responses, which combines an auxiliary LLM and four evaluation metrics to assess how target LLMs analyze obfuscated code comprehensively. Experimental results show that Acoda can effectively induce LLMs to refuse or misinterpret code analysis. On 7 state-of-the-art LLMs, including GPT-4o, DeepSeek, Qwen, Llama, and Gemma, Acoda achieves an attack success rate (ASR) of up to 70%, with strong cross-model transferability and minimal runtime overhead, while ensuring that the semantics of the original code remain unchanged. Overall, this study provides a new perspective for code protection and LLM security defense in the era of LLMs.

2606.11754 2026-06-11 math.AG math.GR 新提交

Non-symplectic Indices of Automorphism Groups of Smooth Cubic Fourfolds

光滑四次三维流形自同构群的非辛指数

Jie Fu, Shihao Wang, Zhiwei Zheng

AI总结 研究具有给定辛自同构群的光滑四次三维流形的全自同构群,通过群论和格论方法限制非辛指数,并分类秩19余不变格的所有可能自同构群对。

Comments 30 pages, comments welcome!

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AI中文摘要

我们研究了具有给定辛自同构群的光滑四次三维流形的全自同构群。我们的出发点是Laza和Zheng对辛自同构群的分类。我们关注非辛指数,即辛自同构群在全自同构群中的指数。我们证明了该指数的一般限制。我们还通过群论和格论方法计算了界限。在若干情况下,我们确定了所有可能的指数。对于秩为19的余不变格,我们分类了所有可能的由辛自同构群和全自同构群组成的对。

英文摘要

We study the full automorphism groups of smooth cubic fourfolds with prescribed symplectic automorphism group. Our starting point is the classification of symplectic automorphism groups by Laza and Zheng. We focus on the non-symplectic index, namely, the index of the symplectic automorphism group in the full automorphism group. We prove general restrictions on this index. We also compute bounds by group-theoretic and lattice-theoretic methods. In several cases, we determine all possible indices. For coinvariant lattices of rank 19, we classify all possible pairs consisting of the symplectic automorphism group and the full automorphism group.

2606.11753 2026-06-11 physics.optics 新提交

Polarization-Selective Near-Perfect Absorption via Mie-Type Resonance in van der Waals Anisotropic ReS$_2$/$α$-MoO$_3$/Au Heterostructure

基于范德华各向异性ReS$_2$/$α$-MoO$_3$/Au异质结构中米氏共振的偏振选择近完美吸收

Shoumik Debnath, Sudipta Saha

AI总结 通过时域有限差分模拟,研究由ReS₂条纹光栅、α-MoO₃间隔层和金背反射镜组成的可见光异质结构中的偏振选择吸收,实现了TE偏振下650.5 nm处99.99%的近完美吸收,并揭示了各向异性层对共振和偏振选择性的调控作用。

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AI中文摘要

我们使用时域有限差分模拟研究了由ReS$_2$条纹光栅、$\alpha$-MoO$_3$间隔层和金背反射镜组成的可见光波长异质结构中的偏振选择吸收。对于优化几何结构(光栅周期500 nm,条纹宽度250 nm,ReS$_2$厚度80 nm),该结构在TE偏振照明下于650.5 nm处表现出99.99%的近完美吸收。共振场集中在ReS$_2$条纹的外边缘附近,而吸收功率密度也局域在同一区域,与局域边缘模式一致。吸收响应强烈依赖于偏振,产生16.2 nm的TE-TM共振分离。将双轴ReS$_2$层或各向异性$\alpha$-MoO$_3$间隔层替换为各向同性等效层会显著改变光谱响应并减小偏振依赖的波长分离。此外,旋转ReS$_2$/$\alpha$-MoO$_3$堆叠的晶体取向会改变共振波长和峰值吸收,而无需改变器件几何结构。结果表明,各向异性谐振器和间隔层的组合为控制范德华光子结构中的共振吸收和偏振选择性提供了一种有效手段。

英文摘要

We investigate polarization-selective absorption in a visible-wavelength heterostructure consisting of a ReS$_2$ stripe grating, an $α$-MoO$_3$ spacer, and an Au back-reflector using finite-difference time-domain simulations. For an optimized geometry with a grating period of 500 nm, stripe width of 250 nm, and ReS$_2$ thickness of 80 nm, the structure exhibits near-unity absorption of 99.99\% at 650.5 nm under TE-polarized illumination. The resonant field is concentrated near the outer edges of the ReS$_2$ stripe, while absorption power density is localized in the same region, consistent with a localized edge mode. The absorption response depends strongly on polarization, producing a TE--TM resonance separation of 16.2 nm. Replacing either the biaxial ReS$_2$ layer or the anisotropic $α$-MoO$_3$ spacer with isotropic equivalents substantially modifies the spectral response and reduces the polarization-dependent wavelength separation. In addition, rotating the crystal orientation of the ReS$_2$/$α$-MoO$_3$ stack shifts both the resonance wavelength and peak absorption without changing the device geometry. The results show that the combination of anisotropic resonator and spacer layers provides an effective means of controlling resonant absorption and polarization selectivity in van der Waals photonic structures.

2606.11752 2026-06-11 cond-mat.mes-hall cond-mat.mtrl-sci 新提交

Spin-Orbit Torque and Magnetization Switching in 2D Ferromagnetic Devices

二维铁磁器件中的自旋轨道转矩与磁化翻转

Bao-Huei Huang, Hong Guo, Yu-Hui Tang

AI总结 通过第一性原理计算研究范德华异质双层Cr3Te4/PtTe2中的非平衡自旋转矩,发现局域自旋感应产生类场转矩主导面内磁各向异性体系的翻转电流,并强调优化NM层自旋霍尔效应和FM层Rashba效应分别对垂直和面内磁各向异性翻转的重要性。

Comments 15 pages, 14 figures

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Journal ref
Physical Review B 113, 224421 (2026)
AI中文摘要

电流诱导的自旋轨道转矩已成为操控基于铁磁体/非磁体(FM/NM)存储单元磁化翻转的有力技术。通过研究范德华异质双层三角晶格Cr3Te4/PtTe2中的非平衡自旋转矩效应,采用第一性原理量子输运计算来确定局域自旋感应(由FM层中的Rashba-Edelstein效应产生)和自旋电流注入(从NM层流向FM层)。我们的工作揭示,局域自旋感应显著产生类场转矩,该转矩主要主导具有强面内磁各向异性体系中的翻转电流。我们的工作强调了优化NM层中的自旋霍尔效应用于基于垂直磁各向异性(PMA)的磁化翻转,以及最大化FM层中的Rashba效应用于基于面内磁各向异性(IMA)的翻转的重要性。

英文摘要

Current-induced spin-orbit torque has emerged as a powerful technique for manipulating magnetization switching of ferromagnet/nonmagnet (FM/NM) based memory cell. By investigating nonequilibrium spin torque effect in a van der Waals heterobilayer, trigonal $\text{Cr}_{3}\text{Te}_{4}/\text{PtTe}_{2}$, the first-principles quantum transport calculations are applied to determine both local spin induction, resulting from Rashba-Edelstein effect in the FM layer, and spin current injection, flowing from the NM to the FM layer. Our work reveals that local spin induction significantly generates the fieldlike torque, which primarily governs the switching current in systems with strong in-plane magnetic anisotropy. Our work emphasizes the importance of optimizing spin Hall effect in the NM layer for perpendicular magnetic anisotropy (PMA)-based magnetization switching and maximizing the Rashba effect in the FM layer for in-plane magnetic anisotropy (IMA)-based switching.

2606.11750 2026-06-11 math.LO cs.LO 新提交

Russell's Theory of Definite Descriptions in the Light of Structural Proof Theory

罗素的限定摹状词理论在结构证明论视角下的审视

Andrzej Indrzejczak, Nils Kürbis

AI总结 本文从结构证明论角度,系统化、比较并扩展了罗素限定摹状词理论的三种形式化方法(二元量词、iota算子、iota+lambda算子),所有系统满足现代证明论标准(如切割消去)。

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Journal ref
Sythese 2026
AI中文摘要

在《论指称》中,罗素提出了最具影响力的限定摹状词理论,即形如“the F”的表达。罗素方法的特征在于,限定摹状词不被视为表面上的单称词项,而是通过语境定义消除。罗素在形如“The F is G”的完整句子语境中形式化限定摹状词,这需要作用域标记来区分内部否定和外部否定。然而,Burge、Kalish和Montague认识到,罗素方法的基本特征可以在尊重限定摹状词所属句法范畴的同时进行形式化。Neale青睐的另一种方法遵循罗素,将完整句子“The F is G”用二元量词形式化。限定摹状词理论对逻辑、数学和哲学的不可否认的重要性要求其形式化必须满足现代证明论的标准。这正是本文的主题。我们系统化、比较并扩展了现有方法。在呈现其基本特征后,我们在相继式演算中形式化了罗素的限定摹状词理论。将考虑三种方法:第一种使用二元量词,其余两种使用形成词项的iota算子。其中一种仅使用iota算子,另一种额外使用lambda算子作为作用域标记。所有系统均满足现代证明论的标准,特别是切割消去。附录将这些系统重述为自然演绎形式,更便于实际应用。

英文摘要

In 'On Denoting' Russell proposed the most influential theory of definite descriptions, expressions of the form 'the F'. Characteristic for Russell's approach is that definite descriptions are not treated as what they appear to be on the surface, i.e. as singular terms. Instead they are eliminated by a contextual definition. Russell formalises definite descriptions in the context of complete sentences of the form 'The F is G'. This requires scope markers to distinguish, e.g., internal from external negation. It was recognised by Burge, and Kalish and Montague, however, that the essential features of Russell's approach may be formalised while respecting the syntactic category to which definite descriptions appear to belong. An alternative, favoured by Neale, follows Russell in that complete sentences 'The F is G' are formalised by a binary quantifier. The undeniable importance of the theory of definite descriptions for logic, mathematics and philosophy demands that it be formalised to meet the standards of modern proof theory. This is the topic of the present paper. We systematise, compare and extend existing approaches. After presenting its essential features, we formalise Russell's theory of definite descriptions in sequent calculus. Three approaches will be considered. The first uses a binary quantifier, whereas the remaining two employ the term-forming iota operator. The first of these employs only the iota operator, the other employs in addition the lambda operator which does duty as a scope marker. All systems satisfy the standards for modern proof theory, in particular cut elimination. The appendix reformulates these systems in natural deduction, which is more convenient for practical purposes.

2606.11749 2026-06-11 cs.IR 新提交

FAST-MEL: A Fast, Accurate, and Storage Efficient Solution for Multimodal Entity Linking

FAST-MEL: 一种快速、准确且存储高效的多模态实体链接解决方案

Derrien Thomas, Laurent Amsaleg, Pascale Sébillot

AI总结 提出FAST-MEL,通过紧凑的固定大小向量化表示文本和视觉信息,在保持高准确率的同时实现三个数量级的加速和一个数量级的存储节省。

详情
Journal ref
SIGIR 2026
AI中文摘要

多模态实体链接(MEL)是将非结构化数据中实体的文本和视觉提及与知识库(KB)中对应实体匹配的任务。为了在大规模实际场景中有效,MEL系统必须满足三个目标:高链接准确率、计算效率和存储效率,即紧凑且高效的KB索引。在本文中,我们强调现有系统无法同时满足这三个要求。为了实现这一三重目标,我们提出了FAST-MEL,一种轻量级的基于编码器的MEL解决方案,它依赖于每个实体或提及的文本和视觉信息的新型紧凑固定大小向量化表示。它在匹配最佳系统准确率的同时,执行速度快三个数量级,并且比最快系统消耗少一个数量级的存储。

英文摘要

Multimodal entity linking (MEL) is the task that consists of matching textual and visual mentions of entities in unstructured data to their corresponding entities in a knowledge base (KB). To be effective in large-scale practical settings, MEL systems must meet three objectives: high linking accuracy, computational efficiency, and storage efficiency, i.e., a compact yet efficient index of the KB. In this paper, we highlight that state-of-the-art systems fail to simultaneously satisfy these 3 requirements. To meet this three-fold objective, we propose FAST-MEL, a lightweight encoder-based MEL solution that relies on a novel and compact fixed-size vectorized representation of both the textual and visual information of each entity or mention. It matches the accuracy of the best systems but performs three orders of magnitude faster. It also consumes one order of magnitude less storage than the fastest systems.

2606.11748 2026-06-11 astro-ph.HE astro-ph.SR 新提交

An Exploration of Recombination of Uranium with application to Kilonovae Spectra

铀的复合及其在千新星光谱中的应用探索

Niamh Ferguson, Anders Jerkstrand, Smaranika Banerjee, Martin. G. O'Mullane, Nigel. R. Badnell

AI总结 针对千新星非局部热力学平衡阶段主导的双电子复合过程,利用AUTOSTRUCTURE优化开放f壳层铀离子U II-U IV的复合速率系数,并通过Nd III基准验证,以改进辐射传输计算中光谱对复合物理的敏感性。

Comments 11 Pages, 5 figures

详情
AI中文摘要

双电子复合(DR)预计是千新星非局部热力学平衡(non-LTE)阶段的主要复合过程,然而大多数重离子仍缺乏可靠的DR数据。因此,当前的光谱模型依赖于简化的复合方案,给预测光谱带来了显著的不确定性。我们提出了一种针对开放f壳层离子的优化策略,使用\ exttt{AUTOSTRUCTURE},目标是千新星抛射物中相关的铀离子U II--U IV。作为基准案例,对Nd III进行了计算,以验证f壳层结构及其对DR影响的处理。得到的DR速率系数在千新星等离子体相关温度下约为$10^{-10}$--$10^{-12}$ cm$^{3}$s$^{-1}$。优化后的速率旨在用于\ exttt{SUMO}的辐射传输计算,以评估千新星光谱对改进复合物理的敏感性。Nd III基准表明,原子结构的改进可以引起光谱特征的可测量变化,这为锕系离子的类似计算提供了动力。

英文摘要

Dielectronic recombination (DR) is expected to be the dominant recombination process during the non-local thermodynamic equilibrium (non-LTE) phase of kilonovae, yet reliable DR data remain unavailable for most heavy ions. Current spectral models therefore rely on simplified recombination prescriptions, introducing significant uncertainties into predicted spectra. We present an optimization strategy for open f-shell ions using \texttt{AUTOSTRUCTURE}, targeting uranium ions U II--U IV relevant to kilonova ejecta. As a benchmark case, calculations are performed for Nd III to validate the treatment of the f-shell structure and its impact on DR. The resulting DR rate coefficients are of order $10^{-10}$--$10^{-12}$ cm$^{3}$s$^{-1}$ over temperatures relevant to kilonova plasmas. The optimized rates are intended for implementation in radiative-transfer calculations with \texttt{SUMO} to assess the sensitivity of kilonova spectra to improved recombination physics. The Nd III benchmark demonstrates that refinements to the atomic structure can produce measurable changes in spectral features, motivating similar calculations for actinide ions.

2606.11747 2026-06-11 physics.atom-ph 新提交

Ambiguity-Free Inertial Measurement with Multi-Wavelength Atom Interferometry

多波长原子干涉仪的无模糊惯性测量

Wei-Chen Jia, Yue Xin, Ke Shen, Yan-Ying Feng

AI总结 通过多波长原子干涉合成包络实现无模糊惯性测量,实验演示了双轴旋转与加速度传感,并解决了传统原子干涉仪的相位模糊问题。

Comments 10 pages,4 figures

详情
AI中文摘要

白光干涉通过合成多个光学波长的干涉包络实现无模糊定位,但相干物质波尚未实现类似能力。本文首次实验演示了多波长原子干涉,建立了白光干涉的物质波对应。通过利用反向传播原子束作为多波长物质波源并合成其光谱分量的干涉包络,我们实现了基于包络定位而非传统条纹相位估计的惯性测量。由此产生的多尺度干涉响应提供了无模糊操作、明确的旋转比例因子以及对初始相位偏差的降低敏感性。作为原理验证,我们演示了同时双轴旋转和加速度传感,并直接解决了从根本上限制传统开环原子干涉仪的相位模糊。我们进一步测量了地球自转,相对误差为4.3%,在15000秒平均时间下长期稳定性为93 ppm。我们的结果将多波长原子干涉确立为相干物质波传感的新范式,将白光干涉原理扩展到原子光学,并为惯性传感、大地测量、精密计量和惯性导航开辟了新机遇。

英文摘要

White-light interferometry enables ambiguity-free localization by synthesizing interference envelopes from multiple optical wavelengths, but no analogous capability has been realized for coherent matter waves. Here we report the first experimental demonstration of multi-wavelength atom interferometry, establishing the matter-wave counterpart of white-light interferometry. By exploiting counter-propagating atomic beams as multi-wavelength matter wave sources and synthesizing interference envelopes from their spectral components, we realize inertial measurements based on envelope localization rather than conventional fringe-phase estimation. The resulting multi-scale interferometric response provides ambiguity-free operation, a well-defined rotational scale factor, and reduced sensitivity to initial phase bias. As a proof of principle, we demonstrate simultaneous dual-axis rotation and acceleration sensing and directly resolve the phase ambiguity that fundamentally limits conventional open-loop atom interferometers. We further measure the Earth's rotation with a relative error of 4.3% and a long-term stability of 93 ppm at an averaging time of 15,000 s. Our results establish multi-wavelength atom interferometry as a new paradigm for coherent matter-wave sensing, extending the principles of white-light interferometry to atom optics and opening new opportunities for inertial sensing, geodesy, precision metrology, and inertial navigation.