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2605.16098 2026-05-18 cs.CR cs.DC

PCDM: A Diffusion-Based Data Poisoning Attack Against Federated Learning Systems

PCDM:一种基于扩散的数据污染攻击对抗联邦学习系统

Wei Sun, Yijun Chen, Bo Gao, Ke Xiong, Yuwei Wang, Pingyi Fan, Khaled Ben Letaief

AI总结 本文提出基于扩散的数据污染框架,通过Poisoning-Oriented Conditional Diffusion Model实现对联邦学习系统中局部数据污染的精细控制,同时保证攻击效果与隐蔽性。

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AI中文摘要

联邦学习(FL)由于其分布式特性而容易受到数据污染攻击。尽管最近基于GAN的数据污染方法表明了利用生成式AI生成看似合法的污染数据的潜力,但GAN输出的内在一致性仍可能揭示数据污染的迹象。本文提出了一种针对FL系统的基于扩散的数据污染框架,该框架利用面向污染的条件扩散模型(PCDM)以实现对本地污染数据的精细控制,同时确保攻击的有效性和隐蔽性。我们的PCDM在全局上下文中整合可调节的污染向量,以精确控制污染数据的生成,并在理论上保证攻击性能。此外,它采用了一种新颖的跳跃扩散策略以实现轻量级和高效的污染数据生成。我们对FL污染攻击进行了最系统和广泛的实验评估,针对各种防御措施,包括先进的拜占庭鲁棒聚合机制,在四个公开数据集上进行测试:MNIST、Fashion-MNIST、CIFAR-10、CIFAR-100以及一个现实世界的无线专用数据集VRAI。我们的结果表明,与最先进的方法相比,PCDM较少表现出统计异常,同时更有效地降低全局FL性能,这给FL中的数据安全带来了重大风险。

英文摘要

Federated learning (FL) is vulnerable to data poisoning attacks due to its distributed nature. Although recent GAN-based data poisoning methods have indicated the potential of using generative AI to generate seemingly legitimate poisoned data, the inherent consistency of GAN outputs can still reveal a sign of data poisoning. In this paper, we propose a diffusion-based data poisoning framework against FL systems, which leverages a Poisoning-Oriented Conditional Diffusion Model (PCDM) to enable fine-grained control over the local generation of poisoned data while ensuring both attack effectiveness and stealthiness. Our PCDM incorporates an adjustable poisoning vector within the global context to precisely control the generation of poisoned data, with theoretical guarantees on attack performance. Furthermore, it employs a novel jumping diffusion strategy for lightweight and efficient poisoned data generation. We conduct the most systematic and broad experimental evaluation for FL poisoning attacks against various defenses, including advanced Byzantine robust aggregation mechanisms, on four open datasets: MNIST, Fashion-MNIST, CIFAR-10, CIFAR-100, and a real-world wireless-specific dataset VRAI. Our results demonstrate that PCDM is less likely to exhibit statistical anomalies compared with the state-of-the-art methods while more effectively degrading global FL performance, which poses a significant risk to data security in FL.

2605.16097 2026-05-18 cs.MA

Multi-Agent Cooperative Transportation: Optimal and Efficient Task Allocation and Path Finding

多智能体协作运输:最优且高效的任务分配与路径寻找

Ning Zhou, Nikolai W. F. Bode, Edmund R. Hunt

AI总结 本文提出CT-TAPF问题,整合团队形成、任务分配与无碰撞路径寻找,提出CT-TCBS最优求解器和子最优求解器,通过增量扩展策略和全局任务视角提升效率,验证了在协作多智能体问题中的有效性。

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AI中文摘要

多机器人系统在现代物流中至关重要,但其能力通常局限于单个智能体可执行的任务。本文填补了现有框架如多智能体路径寻找(MAPF)和任务分配与路径寻找(TAPF)在运输大物品时缺乏真正协作的空白。我们正式提出了协作运输任务分配与路径寻找(CT-TAPF)问题,整合了团队形成、任务分配和无碰撞路径寻找。我们提出了一种最优求解器,协作运输任务冲突基于搜索(CT-TCBS),其特征是新颖的增量扩展策略,以解决团队形成中的组合爆炸问题。认识到最优解的计算成本,我们还开发了一组子最优求解器,采用全局任务导向视角,根据全局难度度量(最佳任务或最差任务)选择下一个任务分配。我们的全面实证评估展示了三个关键发现:(1)增量扩展策略显著优于朴素组合方法,通过有效剪枝主导的任务分配搜索空间;(2)我们识别了一个任务冲突扩展困境,其中复杂的冲突解决者在大型智能体路径寻找子问题中表现良好,但在整合的CT-TAPF设置中可能有害;(3)我们提出的子最优求解器在解决方案质量-运行时间谱上建立了新的、更高效的前沿,相比“nn-”智能体导向基线。本文为新的实用协作多智能体问题提供了一个基础框架和有效的算法集合。

英文摘要

Multi-robot systems are integral to modern logistics, but their capabilities are often limited to tasks executable by individual agents. This paper addresses a critical gap in existing frameworks like Multi-Agent Path Finding (MAPF) and Task Allocation and Path Finding (TAPF), which lack true cooperation for transporting large items that require multiple agents. To this end, we formalise the Cooperative Transportation Task Allocation and Path Finding (CT-TAPF) problem, which integrates team formation, task assignment, and collision-free pathfinding. We present an optimal solver, Cooperative Transportation Task Conflict-Based Search (CT-TCBS), which features a novel Incremental Expansion strategy to tackle the combinatorial explosion inherent in team formation. Recognising the computational cost of optimality, we also develop a family of sub-optimal solvers that employ a global, task-centric perspective, selecting the next task to assign based on a global difficulty metric (Best Task or Worst Task). Our comprehensive empirical evaluation demonstrates three key findings: (1) the incremental expansion strategy significantly outperforms the naive combinatorial approach by successfully pruning the dominant task-allocation search space; (2) we identify a task-conflict expansion dilemma, where sophisticated conflict resolvers effective for large-agent pathfinding subproblems can be detrimental in the integrated CT-TAPF setting; and (3) our proposed sub-optimal solvers establish a new, more efficient frontier on the solution quality-runtime spectrum compared to "nn-" agent-centric baselines. This work provides a foundational framework and a set of effective algorithms for a new, practical class of cooperative multi-agent problems.

2605.16096 2026-05-18 math.GN math.DS math.FA

Intrinsic uniform structure on median algebras

介质代数上的内在均匀结构

Michael Megrelishvili

AI总结 本文介绍了介质代数上的内在预紧凸均匀结构,该结构在自然假设下为Hausdorff空间,并通过均匀完成得到最小介质紧致化。诱导拓扑提供了线性序集区间拓扑的高维类比。

Comments 26 pages, 1 figure

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AI中文摘要

我们引入了介质均匀性U_m,这是介质代数上的内在预紧凸均匀结构。在自然假设下,例如有限秩介质代数中,它为Hausdorff空间。在Hausdorff情况下,其均匀完成得到最小介质紧致化(MMC)。诱导拓扑τ_m提供了线性序集区间拓扑的高维类比,以及一维介质代数的影子拓扑。当介质代数X的所有区间均为有限时,MMC是(X,τ_m)的唯一proper介质紧致化;特别是,它与Roller紧致化一致。我们应用此均匀框架到拓扑群G的连续作用,通过介质自同构。我们证明MMC是G的介质紧致化。在有限秩情况下,所得的紧G系统可表示为Rosenthal系统,因此动态上是温和的。

英文摘要

We introduce the median uniformity $\mathcal U_{\mathrm m}$, an intrinsic precompact convex uniform structure on a median algebra. It is Hausdorff under natural assumptions, for instance for finite-rank median algebras. In the Hausdorff case, its uniform completion yields the Minimal Median Compactification (MMC). The induced topology $τ_{\mathrm m}$ provides a natural higher-rank analogue of the interval topology on linearly ordered sets and of the shadow topology on rank-one median algebras. When all intervals in the median algebra $X$ are finite, the MMC is the unique proper median compactification of $(X,τ_{\mathrm m})$; in particular, it coincides with the Roller compactification. We apply this uniform framework to continuous actions of a topological group $G$ by median automorphisms. We show that the MMC is a median $G$-compactification. In the finite-rank case, the resulting compact $G$-system is Rosenthal representable and hence dynamically tame.

2605.16095 2026-05-18 gr-qc math-ph math.AP math.MP

Nonlinear stability of continuously self-similar naked singularities for the Einstein-scalar field equations II: linearized stability

连续自相似裸奇点对爱因斯坦-标量场方程非线性稳定性的研究 II:线性稳定性

Jaydeep Singh, Weihao Zheng

AI总结 本文研究连续自相似裸奇点在爱因斯坦-标量场方程下的线性稳定性,揭示了正则性在蓝移不稳定性中的关键作用,与前人结果形成对比。

Comments 88 pages

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AI中文摘要

本文是关于证明连续自相似$C^{1,α}$裸奇点解对球对称爱因斯坦-标量场方程非线性稳定性的系列论文第二部分。这些解由Christodoulou构造,已知在足够粗糙扰动下不稳定,但本文在与背景相同正则性下证明其线性稳定性,揭示正则性在蓝移不稳定性机制中的核心作用,并显示该机制在背景时空正则性水平上未被触发。本文的线性分析为 companion paper [W. Zheng, Nonlinear stability of the continuous self-similar naked singularities for the Einstein-scalar field equations I: main results] 中的非线性稳定性结果提供了基础。

英文摘要

This is the second part of a series of papers proving the nonlinear stability of a one-parameter family of continuous self-similar $C^{1,α}$ naked singularity solutions, with $0<α\ll1$, to the spherically symmetric Einstein-scalar field equations. These solutions were constructed by Christodoulou and are known to be unstable under sufficiently rough perturbations due to the blue-shift instability mechanism. In complete contrast to the previous instability results, we establish the linearized stability for those naked singularity spacetimes under perturbations of the same regularity as the background, revealing the central role of regularity in determining the strength of the blue-shift instability mechanism, and showing that it is not triggered at the regularity level of the background spacetime. The linear analysis carried out in this paper provides the foundation for the nonlinear stability result established in the companion paper [W. Zheng, Nonlinear stability of the continuous self-similar naked singularities for the Einstein-scalar field equations I: main results]. Together with that companion paper, this yields the nonlinear stability of these continuously self-similar naked singularities.

2605.16093 2026-05-18 quant-ph

Unbounded Communication Power of a Qubit

单个量子比特的无界通信功率

Souradeep Sasmal, Som Kanjilal, Debarshi Das

AI总结 研究探讨单个量子比特在多次解码后仍能保持信息访问的能力,通过引入发送端的制备区分度与接收端的测量不相容性,揭示了量子优势可无限延续的通信特性。

Comments Preliminary draft. Comments welcome

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AI中文摘要

量子力学即使在单个量子比特层面也赋予信息处理优势。典型例子是2→1随机访问码(RAC),其中量子比特在检索编码信息上优于经典比特。然而,标准形式下这种量子优势仅限于单个接收者,因为解码测量不可避免地破坏编码信息。相反,本文探讨信息编码在单个量子比特中在多次解码后仍能保持可访问性的持续时间。引入发送端的制备区分度作为操作资源,显示其与接收端测量不相容性的相互作用可缓解测量引起的干扰,从而允许任意长的接收者序列各自保留量子优势。结果表明,即使在重复测量下,量子比特中编码的信息也不必完全耗尽,揭示了比之前认识更强大的通信特性。

英文摘要

Quantum mechanics enables information-processing advantages even at the level of a single qubit. A paradigmatic example is the 2$\to$1 random access code (RAC), where a qubit outperforms a classical bit in retrieving encoded information. In the standard form, however, this quantum advantage is restricted to a single receiver, since decoding measurements inevitably destroy the encoded information. Contrary to this, we address how long the information encoded in a single qubit remains accessible even after multiple decoding, each with a quantum advantage. Introducing preparation distinguishability as an operational resource associated with the sender, we show that its interplay with measurement incompatibility on the receiver's side can mitigate measurement-induced disturbance, thereby enabling an arbitrarily long sequence of receivers to each retain a quantum advantage. Our results show that, even under repeated measurements, the information encoded in a qubit need not be entirely exhausted, revealing a stronger communication feature than previously recognised.

2605.16092 2026-05-18 math.NT math.AG

On Drinfeld's representability theorem

关于德林费尔德可代表性定理

Arnaud Vanhaecke

AI总结 本文提供德林费尔德可代表性定理的新证明,并详细阐述其模空间与p-adic对称空间的正式模型。

Comments Preliminary version; comments are welcome !

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AI中文摘要

在70年代,V.G.德林费尔德证明了某些具有额外作用的p-除数群的变形由准同源性所代表的模问题可通过显式半稳定模型表示。该定理是p-adic Hodge理论几何方面的重要基石。本文旨在两方面:一方面给出德林费尔德可代表性定理的新且更清晰的证明;另一方面详细阐述德林费尔德的模空间和p-adic对称空间的正式模型。

英文摘要

In the seventies, V. G. Drinfeld proved that a moduli problem of deformations by quasi-isogenies of certain $p$-divisible groups with extra actions is representable by an explicit semi-stable model of the $p$-adic symmetric space. This theorem, known as \emph{Drinfeld's representability theorem}, has been one of the cornerstones of geometric aspects in $p$-adic Hodge theory. The purpose of these notes is twofold. On the one hand we give a new and more transparent proof of Drinfeld's representability theorem; on the other hand, we give a detailed presentation of Drinfeld's moduli space and the formal model of the $p$-adic symmetric space.

2605.16091 2026-05-18 cond-mat.dis-nn cond-mat.mtrl-sci

Machine learning potential as a guide for eutectic in ultra-refractory multicomponent ceramics

机器学习潜力作为超难熔多组分陶瓷共晶的指导

V. E. Valiulin, A. V. Mikheyenkov, N. M. Chtchelkatchev, E. A. Levashov

AI总结 本文提出一种基于机器学习的新型方法,用于确定超难熔合金的共晶点浓度,通过Ti-B-C系统验证,利用神经网络构建的互原子势能模型在液相中有效工作,无需考虑固态合金的晶体结构。

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Journal ref
J. Chem. Phys. 164, 054504 (2026)
AI中文摘要

实验确定共晶点是一种长期建立且广泛应用的技术,但通常仅适用于熔点相对较低的系统。许多现代有前景的材料却是超难熔的,熔点超过3000 K。对于这些系统,传统熔融实验变得过于昂贵和技术挑战。先进的AI建模可以作为强有力的先驱,指导此类实验的成功。本文提出了一种新的确定超难熔合金共晶点浓度的标准。该方法通过Ti-B-C系统验证,这是迄今为止最彻底研究的三组分难熔系统。算法的核心是一种基于神经网络的机器学习互原子势能模型,其精度可与从头计算方法相媲美。关键的是,该算法在液相中有效工作,消除了估计共晶点时需要了解固态合金晶体结构的必要性。

英文摘要

The experimental determination of eutectic points is a long-established and widely used technique, but it is generally only practical for systems with relatively low melting points. Many modern, promising materials, however, are ultra-refractory, with melting points exceeding 3000 K. For these systems, conventional melting experiments become prohibitively expensive and technically challenging. Advanced AI modeling can serve as a powerful precursor to guide successful experimentation in such cases. This work proposes a novel criterion for determining the eutectic point concentration in ultra-refractory alloys. The approach is verified using the Ti-B-C system - the most thoroughly studied three-component refractory system to date. The core of the algorithm is a machine-learning interatomic potential, based on a neural network, which achieves accuracy comparable to ab initio methods. Crucially, the algorithm operates effectively in the liquid phase, eliminating the need for information about the solid alloy's crystalline structure to estimate eutectic points.

2605.16086 2026-05-18 math.PR

Loop pruning and downward deviations for maximum local time of discrete-time simple random walks

环剪枝与离散时间简单随机游走最大局部时间的向下偏差

Xinyi Li, Yushu Zheng

AI总结 研究离散时间简单随机游走在Z^d(d≥3)上最大局部时间的向下偏差,通过证明下界获得精确渐近公式,并引入环剪枝随机游走结构。

Comments 45 pages, 6 figures

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AI中文摘要

我们研究离散时间简单随机游走在Z^d(d≥3)上最大局部时间的向下偏差。在我们之前的论文[li2026ldmaxlocal]中,建立了相应的上界,而匹配的下界仍未解决。在本文中,我们证明了这个下界,从而获得了向下偏差概率的精确渐近公式。为了提供连续时间论证中跳跃链/持有时间结构的离散时间类比,我们引入了一种新的随机结构,称为环剪枝随机游走及其相关的环剪枝分解,这也具有独立价值。

英文摘要

We study downward deviations of the maximum local time of the discrete-time simple random walk on $\mathbb{Z}^d$, $d\ge 3$. In our previous paper \cite{li2026ldmaxlocal}, the corresponding upper bound was established, while the matching lower bound was left open. In the present paper, we prove this lower bound and hence obtain the sharp asymptotic formula for the downward-deviation probability. To provide a discrete-time analogue of the jump-chain/holding-time structure used in the continuous-time argument, we introduce a new random structure which we name as {\it loop-pruned random walk} and the associated loop-pruning decomposition, which is also of independent interest.

2605.16084 2026-05-18 astro-ph.CO

A model-independent test of the cosmic distance-duality relation using galaxy clusters and Type Ia supernovae matched pairs

基于星系团和Ia型超新星匹配对的宇宙距离-双关系模型无关检验

Jian Hu, Yi Liu, Jian-Ping Hu, Zhongmu Li

AI总结 利用38个星系团和Pantheon+样本中的Ia型超新星匹配对,对宇宙距离-双关系进行模型无关检验,发现无显著违反证据,且推导出宇宙学无关的M0值。

Comments 9 pages, 5 figures, Submitted to Astronomy & Astrophysics (A&A)

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AI中文摘要

宇宙距离-双关系(CDDR),表达为$ D_L/D_A(1+z)^{-2}=1 $,是连接光度距离($ D_L $)和角直径距离($ D_A $)的基本关系。任何偏离该关系都可能表明新物理,如光子非守恒、宇宙不透明或非度量引力。我们利用Bonamente等人编译的38个星系团和Pantheon+样本中的Ia型超新星匹配对,对CDDR进行严格、模型无关的检验。通过匹配对技术,我们同时约束了CDDR违反参数$ η$和Ia型超新星绝对光度的可能红移演化,参数化为$ M_B(z)=M_0 + \varepsilon z $。我们评估了匹配容忍度的稳健性,并进一步补充了DESI 2024 BAO测量。我们的结果得到$ η= 0.050^{+0.348}_{-0.307} $和$ \varepsilon = -0.184^{+0.724}_{-0.574} $(68%置信区间),表明无显著的CDDR违反或Ia型超新星演化证据。在更严格的匹配标准和包含DESI BAO数据的情况下,结论保持不变。我们还推导出宇宙学无关的$ M_0 = -19.460^{+0.126}_{-0.124} $ mag。标准宇宙学模型在这一模型无关的检验下仍保持稳健。

英文摘要

The cosmic distance-duality relation (CDDR), expressed as $ D_L/D_A(1+z)^{-2}=1 $, is a fundamental relation in cosmology connecting luminosity distance ($ D_L $) and angular diameter distance ($ D_A $). Any departure from this relation would indicate new physics such as photon non-conservation, cosmic opacity, or non-metric gravity. We perform a stringent, model-independent test of the CDDR using a matched sample of 38 galaxy clusters from the Bonamente et al. compilation and Type Ia supernovae from the Pantheon+ sample. Employing the matched-pair technique, we simultaneously constrain the CDDR-violation parameter $ η$ and a possible redshift evolution of the SNe Ia absolute magnitude, parameterized as $ M_B(z)=M_0 + \varepsilon z $. We assess the robustness against matching tolerance and further supplement the analysis with DESI 2024 BAO measurements. Our results yield $ η= 0.050^{+0.348}_{-0.307} $ and $ \varepsilon = -0.184^{+0.724}_{-0.574} $ (68% CL), showing no statistically significant evidence for CDDR violation or SNe Ia evolution. The conclusions remain unchanged with stricter matching criteria and the inclusion of DESI BAO data. We also derive a cosmology-independent calibration of $ M_0 = -19.460^{+0.126}_{-0.124} $ mag. The standard cosmological model remains robust under this model-independent scrutiny.

2605.16082 2026-05-18 cs.DC physics.ao-ph physics.comp-ph physics.flu-dyn

An efficient multi-GPU implementation for the Discontinuous Galerkin ocean model SLIM

一种高效的多GPU实现用于不连续伽辽金海洋模型SLIM

Miguel De Le Court, Vincent Legat, Ange P. Ishimwe, Colin Scherpereel, Emmanuel Hanert, Jonathan Lambrechts

AI总结 本文提出一种优化的3D不连续伽辽金海洋模型,适用于单多GPU系统,通过内存布局优化、并行化和矩阵自由求解器提升性能,实验证明GPU在海洋模拟中的高效性。

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AI中文摘要

无结构网格海洋模型因能表示复杂几何和局部网格细化而被越来越多用于近岸应用。然而,其广泛应用受到高计算成本的阻碍,尤其是基于不连续伽辽金有限元(DG-FE)方法的模型,其自由度远高于传统有限体积或连续有限元方法。随着基于GPU的高性能计算架构的快速发展,DG-FE方法因其本质上适合大规模并行计算而成为解决这一限制的途径。本文提出一个完整的3D DG-FE海洋模型实现,优化了单GPU和多GPU系统,支持NVIDIA和AMD架构。我们详细描述了实现高性能的计算策略,包括内存布局优化、核级别并行化和关键垂直过程的矩阵自由求解器。基准测试结果表明,单个HPC级GPU(如NVIDIA A100)性能相当于约1500个CPU核心,用4个A100 GPU节点取代128核心CPU节点可实现约50倍的加速。弱扩展效率在1024个GPU上保持稳定。我们进一步在大堡礁的现实应用中展示了模型的能力,实现了比现有最精确模型五倍更精细的空间分辨率,同时保持物理到数值时间比为100。这些结果表明,GPU加速的DG-FE方法如何显著提升无结构网格海洋建模的能力,使超高分辨率近岸模拟成为可能。

英文摘要

Unstructured-mesh ocean models are increasingly used for coastal applications due to their ability to represent complex geometries and apply local grid refinement where needed. However, their broader use has been hindered by their high computational cost, particularly for models based on the Discontinuous Galerkin finite element (DG-FE) method, which involves significantly more degrees of freedom than traditional finite volume or continuous finite element approaches. The rapid emergence of GPU-based high-performance computing architectures now offers a pathway to address this limitation, as DG-FE formulations are inherently well suited to massively parallel, element-wise computations. Here, we present a full 3D DG-FE ocean model implementation optimized for both single- and multi-GPU systems, with support for both NVIDIA and AMD architectures. We detail the computational strategies employed to achieve high performance, including memory layout optimization, kernel-level parallelization, and matrix-free solvers for key vertical processes. Benchmark results demonstrate that a single HPC-grade GPU (e.g. NVIDIA A100) delivers performance equivalent to approximately 1500 CPU cores, while replacing a 128-core CPU node with a 4xA100 GPU node yields a speedup of around 50x. Weak-scaling efficiency is maintained up to 1024 GPUs. We further demonstrate the model's capabilities on a real-world application in the Great Barrier Reef, achieving a spatial resolution five times finer than the most accurate existing model while maintaining a physical-to-numerical time ratio of 100. These results highlight how GPU-accelerated DG-FE methods can dramatically advance the capabilities of unstructured-mesh ocean modeling, enabling ultra-high-resolution coastal simulations that were previously infeasible.

2605.16075 2026-05-18 stat.ME stat.CO

REX-SUB: A Scalable Subsampling Strategy for Modeling Large Spatial Datasets

REX-SUB:一种用于建模大规模空间数据集的可扩展子采样策略

Nicholas Rios, Ben Seiyon Lee

AI总结 本文提出REX-SUB子采样策略,通过随机交换算法高效选择小样本以最小化空间GP模型的预测误差,并结合可扩展的Vecchia近似方法提升计算效率,实验表明其在预测误差和区间评分上优于其他子采样方法。

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AI中文摘要

近年来,数据收集技术的进步导致大规模空间数据集的出现,测量点数量达到数百万级。传统的地理统计模型通常采用高斯过程(GPs)捕捉空间依赖性,但标准GP拟合在如此大规模下变得不可行。一种有前途的解决方案是最佳子采样,即选择优化某一准则的子集。本文提出一种随机交换算法用于子采样(REX-SUB),该算法高效地选择小样本以最小化拟合空间GP模型的预测误差。为进一步提高计算效率,我们嵌入了可扩展的Vecchia近似方法到GP的联合似然中,利用精度矩阵的稀疏性,实现对所选子样本的快速推断。通过模拟研究和对遥感可降水量数据集的应用,我们表明REX-SUB在预测误差和区间评分上均优于其他子采样策略。

英文摘要

Recent advances in data collection technologies have led to the emergence of massive spatial datasets, with measurements obtained at millions of spatial locations. Geostatistical models typically employ Gaussian processes (GPs) to capture spatial dependence, but standard GP fitting becomes prohibitive at such scales. A promising solution is optimal subsampling, where a subset of locations is selected that optimizes a criterion. In this study, we propose a randomized exchange algorithm for subsampling (REX-SUB) which efficiently selects small subsamples that minimize prediction errors in the fitted spatial GP models. To further improve computational efficiency, we embed a scalable Vecchia approximation to the GP's joint likelihood, which takes advantage of sparsity in the precision matrix to enable fast inference on the selected subsamples. Through a simulation study and an application to a remotely sensed precipitable water dataset, we show that REX-SUB yields lower mean squared prediction errors and interval scores compared to competing subsampling strategies.

2605.16074 2026-05-18 quant-ph cs.ET

When Noisy Quantum Order Finding Remains Recoverable for Shor's Algorithm

当噪声量子顺序查找仍可被Shor算法恢复时

Qingxin Yang, Stefano Markidis

AI总结 研究噪声环境下顺序查找的恢复性,通过分析680个IBM量子系统数据,发现残余梳状结构和验证概率质量分布是影响恢复的关键因素,主导验证质量分数是主要指标。

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AI中文摘要

顺序查找是Shor算法的核心子程序。在NISQ硬件上,相位估计输出分布常因噪声扭曲,使正确顺序恢复困难。本文研究噪声顺序查找的恢复性:给定测量精度-寄存器分布,何时标准经典后处理仍能返回真实顺序?我们分析了680个IBM量子系统的问题实例和电路设置数据。对每个分布,我们应用连续分数后处理与模验证,并定义恢复性为恢复的顺序是否等于真实顺序。我们使用四个特征描述每个分布:自相关峰值强度、归一化熵、主导验证质量分数和验证边距分数。我们通过边缘特征比较、单特征AUROC分析和多变量树形分类器评估这些量。我们使用随机森林排列重要性评估哪些量在其他特征已知时提供独特的预测信息。为使分类行为可解释,我们训练了一个决策树,揭示可恢复和不可恢复分布的阈值规则。我们发现恢复性与测量分布中残余梳状结构和验证概率质量在候选分母间的组织方式密切相关。主导验证质量分数是最强的单特征恢复性指标,树形分析显示它也提供主要的可解释阈值描述。某些高度扭曲的分布在一种验证分母主导后处理质量时仍可恢复,而某些明显结构化的分布因经典后处理偏好错误的验证分母而失败。

英文摘要

Order finding is the core subroutine of Shor's algorithm. On NISQ hardware, phase estimation output distributions are often distorted by noise, making correct order recovery difficult. We study recoverability in noisy order finding: given a measured precision-register distribution, when does standard classical post-processing still return the true order? We analyze 680 distributions from IBM quantum systems across problem instances and circuit settings. For each distribution, we apply continued-fraction post-processing with modular verification and define recoverability as whether the recovered order equals the true one. We characterize each distribution using four features: autocorrelation peak strength, normalized entropy, dominant verified mass fraction, and verified margin fraction. We evaluate these quantities using marginal feature comparisons, single-feature AUROC analysis, and multivariate tree-based classifiers. We use random-forest permutation importance to assess which quantities contribute distinct predictive information once the other features are known. To make classification behavior interpretable, we train a decision tree that exposes threshold rules for recoverable and non-recoverable distributions. We find that recoverability is strongly associated with residual comb-like structure in the measured distribution and the way verified probability mass is organized across candidate denominators. The dominant verified mass fraction is the strongest single-feature indicator of recoverability, and tree-based analysis shows it also provides the primary split in an interpretable threshold description. Some highly distorted distributions remain recoverable when one verified denominator dominates the post-processing mass, while some visibly structured distributions fail because classical post-processing favors an incorrect verified denominator.

2605.16073 2026-05-18 cond-mat.mtrl-sci

Charge Transfer from Perovskite Quantum Dots to Multifunctional Ligands with Tethered Molecular Species

从钙钛矿量子点向多功能配体转移带电粒子并连接分子物种

Mariam Kurashvili, Lena S. Stickel, Jordi Llusar, Christian Wilhelm, Fabian Felixberger, Ivana Ivanović-Burmazović, Ivan Infante, Jochen Feldmann, Quinten A. Akkerman

AI总结 研究通过多功能配体增强钙钛矿量子点的电荷传输效率,利用四乙基铵基团和长尾基团实现稳定结合,展示出高效的光激发空穴转移。

Comments 25 Pages, 5 Figures

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Journal ref
ACS Energy Lett. 2025, 10, 6, 2811-2820
AI中文摘要

钙钛矿量子点(pQDs)因其独特的光学性质成为光电子和光催化应用的有前景材料。通过将供体/受体分子连接到pQD表面可增强电荷载体提取或注入。这些分子必须牢固结合到pQD的离子表面而不影响胶体稳定性。我们通过使用含有四级铵结合基团的多功能配体实现这一点,该配体包含用于强pQD表面结合的四级铵基团、用于胶体稳定性的长尾基团以及靠近pQD表面的功能基团。具有费电烯功能化配体的pQDs显示出快速且接近100%效率的光激发空穴转移。密度泛函理论计算揭示了费电烯分子结构在空穴转移后如何重组,影响其电荷分离效率。这种方法也可以扩展到光激发电子和能量转移过程。因此,该策略为创建高效的QD-分子杂化材料提供了蓝图,适用于光催化等应用。

英文摘要

Perovskite quantum dots (pQDs) are promising materials for optoelectronic and photocatalytic applications due to their unique optical properties. To enhance charge carrier extraction or injection donor/acceptor molecules can be tethered to the pQD. These molecules must strongly bind to the ionic surfaces of pQDs without compromising colloidal stability. These we achieve by using multifunctional ligands containing a quaternary ammonium binding group for strong pQDs surface attachment, a long tail group for colloidal stability, and a functional group near the pQD surface. Such pQDs with ferrocene-functionalized ligands show fast photoexcited hole transfer with near-unity efficiency. Density functional theory calculations reveal how ferrocene's molecular structure reorganizes following hole transfer, affecting its charge separation efficiency. This approach can also be extended to in photoexcited electron and energy transfer processes with pQDs. Therefore, this strategy offers a blueprint for creating efficient QD-molecular hybrids for applications like photocatalysis.

2605.16072 2026-05-18 math.PR

Stochastic integration with respect to a Lévy basis

关于莱维基的随机积分

Markus Riedle

AI总结 本文研究了针对莱维基的可预测积分的随机积分理论,基于切线序列的解耦不等式,将随机积分的构造简化为无限可分随机测度的确定性积分理论。

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AI中文摘要

我们开发了针对莱维基的可预测积分的随机积分理论。我们的方法基于切线序列的解耦不等式,将随机积分的构造本质上简化为由Rajput和Rosiński发展出的无限可分随机测度的确定性积分理论。我们以驱动随机测度相关的半鞅特征来表征可积分的可预测过程的相应类别,并证明所得到的积分空间具有自然的Musielak-Orlicz类型结构,配备F-范数。此外,我们建立了积分算子的连续性性质以及勒贝格支配收敛定理的随机版本。

英文摘要

We develop a stochastic integration theory for predictable integrands with respect to a Lévy basis. Our approach is based on decoupling inequalities for tangent sequences and reduces the construction of the stochastic integral essentially to the deterministic integration theory for infinitely divisible random measures developed by Rajput and Rosiński. We characterise the corresponding class of integrable predictable processes in terms of the semimartingale characteristics associated with the driving random measure and show that the resulting space of integrands possesses a natural Musielak-Orlicz type structure equipped with an F-norm. Furthermore, we establish continuity properties of the integral operator and a stochastic version of Lebesgue's dominated convergence theorem.

2605.16071 2026-05-18 eess.SY cs.SY

Active Learning MPC Objective Functions from Preferences

基于偏好的主动学习MPC目标函数

Hasna El Hasnaouy, Pablo Krupa, Mario Zanon, Alberto Bemporad

AI总结 本文提出两种主动学习策略,通过人类对轨迹对的偏好学习MPC目标函数,减少查询次数以获得更符合偏好的闭环行为。

Comments (6 pages, 3 figures)

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AI中文摘要

在模型预测控制(MPC)中,当性能评估标准仅能通过人类判断获得时,设计目标函数具有挑战性。我们采用基于偏好的学习(PbL)方法从轨迹对的偏好中学习MPC目标函数。然而,PbL在现实中的应用常受限于人类偏好查询的成本或可用性。为此,主动学习(AL)策略旨在提高采样效率,减少获取高性能分类器所需的标注努力。本文提出两种AL策略,用于从人类对成对系统轨迹的偏好中学习MPC目标函数:一种基于池的策略,选择当前代理下不确定且与之前标注比较多样化的轨迹对;另一种查询合成策略,利用当前代理驱动的MPC引入新轨迹。数值结果表明,所提策略在较少查询次数下能产生更符合表达偏好的闭环行为,优于随机采样方法。

英文摘要

Designing the objective function in Model Predictive Control (MPC) is challenging when performance assessment criteria are available only from human judgment. We adopt a preference-based learning (PbL) approach to learn the MPC objective function from preferences over trajectory pairs. However, the real-world application of PbL is often restricted by the significant cost or limited availability of human preference queries. To address this, Active Learning (AL) strategies seek to improve sampling efficiency, reducing the labeling effort required to obtain a well-performing classifier. We present two AL strategies for learning the MPC objective function from human preferences over pairwise system trajectories: a pool-based strategy that selects trajectory pairs that are both uncertain under the current surrogate and diverse relative to previously labeled comparisons, and a query-synthesis strategy that incorporates new trajectories using the current surrogate-driven MPC. Numerical results show that the proposed strategies yield closed-loop behaviors that align more with the expressed preference using fewer number of queries compared to a random sampling approach.

2605.16070 2026-05-18 cond-mat.soft physics.bio-ph

Biophysical Considerations for Rational Antibody and ADC Design

抗体与ADC设计的生物物理考虑

Alberto Ocana, Jorge R. Espinosa

AI总结 研究通过计算生物物理方法揭示抗体、连接子和药物的结构耦合关系,以优化ADC设计的效能与安全性。

Comments 16 pages, 2 figures

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AI中文摘要

基于抗体的治疗药物,包括抗体药物偶联物(ADCs)、双特异性抗体和新型格式,正在重塑肿瘤学领域,但关键的疗效、安全性和可制造性因素常在偶联和制剂后才显现。我们主张计算生物物理提供了一个被低估的框架,通过连接分子相互作用到生物结果来填补这一空白。我们强调分子动力学、粗粒模拟和自由能计算如何揭示偶联位点、连接子化学和药物-抗体比如何重塑构象景观。我们强调抗体、连接子和负载之间的结构耦合,对抗原结合、内化和可开发性有影响。我们提出将基于物理的建模整合到开发流程中,结合实验验证,可以减少经验性迭代并降低转化风险。随着力场和混合物理-机器学习方法的改进,这一领域有望成为下一代ADC设计的核心驱动力。

英文摘要

Antibody-based therapeutics-including antibody-drug conjugates (ADCs), bispecific antibodies, and novel formats-are reshaping oncology, yet key determinants of efficacy, safety, and manufacturability frequently emerge after conjugation and formulation. We argue that computational biophysics provides an underexploited framework to address this gap by connecting molecular interactions to biological outcomes. We highlight how molecular dynamics, coarse-grained simulations, and free energy calculations reveal how conjugation site, linker chemistry, and drug-antibody ratio reshape conformational landscapes. We emphasize structural coupling between antibody, linker, and payload, with implications for antigen binding, internalization, and developability. We propose that integrating physics-based modeling into development pipelines-alongside experimental validation-can reduce empirical iteration and de-risk translation. As force fields, and hybrid physics-machine-learning methods improve, this field is poised to become a central driver of next-generation ADC design.

2605.16068 2026-05-18 cs.DB

Relational Database Data Lineage Ontology

关系数据库数据血缘本体

Jakub Dutkiewicz, Paweł Misiorek, Robert Wrembel

AI总结 本文提出一种新的关系数据库数据血缘本体,通过知识图谱发现血缘链接,增强了语义表示并改进了血缘预测性能。

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AI中文摘要

在关系数据库中建模数据血缘仍是一个具有挑战性的问题,特别是在涉及数据库对象之间不完整或缺失依赖关系的场景中。本文提出了一种新的关系数据库数据血缘本体,旨在提供更丰富和更具表现力的语义表示,以支持通过知识图谱(KGs)发现血缘链接。在我们之前基于KG的血缘发现工作基础上,所提出的本体扩展了先前模型,增加了捕捉关系数据结构、语义和转换级别特征的概念。这些扩展使血缘证据的编码更加精确。为了评估所提本体的影响,我们使用基于KG的归纳链接预测框架进行了比较研究。具体而言,我们评估了基于路径嵌入的图神经网络模型在两种设置下的性能:使用原始基准本体和新提出的本体。实验结果表明,应用增强的语义模型在血缘链接预测性能上有所提高,以AUC和Hits@10指标衡量。

英文摘要

Modeling data lineage in relational databases remains a challenging problem, particularly in scenarios involving incomplete or missing dependencies between database objects. In this paper, we propose a novel ontology for relational database data lineage, designed to provide a richer and more expressive semantic representation supporting discovering the lineage links by means of knowledge graphs (KGs). Building upon our previous work on KG-based lineage discovery, the proposed ontology extends the earlier model with additional concepts capturing structural, semantic, and transformation-level characteristics of relational data. These extensions enable more precise encoding of lineage evidence. To evaluate the impact of the proposed ontology, we conduct a comparative study using a KG-based inductive link prediction framework. Specifically, we assess the performance of a graph neural network model based on path embeddings under two settings: using the original baseline ontology and the newly proposed one. Experimental results demonstrate that the application of the enriched semantic model leads to improvements in lineage link prediction performance, as measured by AUC and Hits@10 metrics.

2605.16066 2026-05-18 stat.AP

A market-calibrated accelerated failure time model for in-play football forecasting

为足球实时投注预测设计的市场校准加速失败时间模型

Lawrence Clegg, Zixing Song, John Cartlidge

AI总结 本文提出一种结合市场信息和实时数据的加速失败时间模型,通过校准球队强度参数和包含赛后预期进球作为时间变异协变量,提升实时足球预测的准确性,并在140场比赛中验证了其效果。

Comments 25 pages, 6 figures, 6 tables

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AI中文摘要

在实时足球预测模型中,难以匹配博彩交易所的价格,这些价格聚合了多个市场参与者的信息。我们通过将Weibull加速失败时间模型的两个扩展相结合来填补这一差距:校准球队强度参数以Betfair交易所开赛时的价格捕捉赛前市场信息,并包含赛后预期进球作为时间变异协变量以捕捉实时信息。校准方法通过平方误差最小化联合拟合球队强度参数到1X2和胜/负投注市场,适用于任何基于强度的目标到达模型,从而增强实时预测能力。在140场英超联赛比赛中,每分钟评估发现校准模型几乎匹配Betfair的分类准确性(70.2% vs 70.6%),同时保留可解释的球队层面参数和协变量效应。与两种替代的连续时间得分模型相比,均校准到相同赛前赔率,证实了市场校准是预测准确性的主导因素。针对Betfair实时赔率的投注模拟显示,17,458笔投注获得4.5%的回报(夏普比率5.94),表明实时足球市场存在不效率。

英文摘要

In-play football forecasting models have struggled to match the accuracy of betting exchange prices, which aggregate information from many market participants. We close this gap by combining two extensions to a Weibull accelerated failure time model: calibrating team strength parameters to Betfair Exchange prices at kick-off to capture pre-match market information, and including post-shot expected goals as a time-varying covariate to capture in-play information. The calibration approach, where we jointly fit team-strength parameters to 1X2 and over/under betting markets via squared-error minimisation, applies to any intensity-based goal arrival model and enables stronger in-play forecasting. Evaluated across 140 English Premier League matches at minute intervals, the calibrated model almost matches Betfair's classification accuracy (70.2% versus 70.6%) while retaining interpretable team-level parameters and covariate effects. A comparison with two alternative continuous-time scoring models, both calibrated to the same pre-match odds, confirms that market calibration is the dominant driver of predictive accuracy. A betting simulation against Betfair in-play odds yields a 4.5% return on investment (Sharpe ratio 5.94) over 17,458 bets, suggesting an inefficiency within in-play football markets.

2605.16063 2026-05-18 math.NT math.AG math.FA

Duality of analytic Hopf algebras and the Amice transform

解析霍普夫代数的对偶性与阿米斯变换

Luca Collauto

AI总结 本文构建了适用于一般巴拿赫环的解析霍普夫代数的全局版本,研究了其对偶理论,并通过基变换成现了阿米斯对偶性,不依赖于特定素数p。

Comments 62 pages

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AI中文摘要

我们构建了适用于一般巴拿赫环的解析霍普夫代数的全局版本,独立于素数p的选择。通过将科赫塔层次和共层次空间推广到任意基巴拿赫环R,并证明了反射性和核性结果。我们展示了如何在这些结构上定义解析霍普夫代数并研究其对偶理论。特别地,研究了围绕1的开单位圆上解析函数的霍普夫代数及其对偶,并通过基变换成现了阿米斯对偶性。当R是具有平凡范数的整环时,我们获得了不依赖于p的全局解析阿米斯对偶性版本。

英文摘要

We construct global versions of the analytic Hopf algebras used in the $p$-adic Fourier theory of Amice and Mahler over a general Banach ring, independently of the choice of prime $p$. This is done by generalising Köthe echelon and coechelon spaces to an arbitrary base Banach ring $R$ and proving reflexivity and nuclearity results. We show how to define an analytic Hopf algebra structure on them and investigate their duality theory. The particular case of the Hopf algebra of analytic functions converging on the open unit disk around $1$ and its dual is studied in detail. Amice duality is recovered from this case by base-change to a $p$-adic ring. Most notably, when $R$ is the ring of integers with the trivial norm, we obtain a global analytic version of Amice duality that does not depend on $p$.

2605.16062 2026-05-18 cond-mat.mes-hall physics.app-ph physics.ins-det

In-situ correlative SEM/KPFM for semiconductor devices and 2D heterostructures

原位相关性SEM/KPFM用于半导体器件和二维异质结构

Prabhu Prasad Swain, Nahid Hosseini, Eveline. S Mayner, Aleksandra Radenovic, Marcos Penedo, Georg E. Fantner

AI总结 本文提出了一种原位单次异步霍夫曼-凯尔文探针力显微镜技术,用于半导体器件和二维异质结构的表征,克服了传统压阻悬臂的电容交叉干扰问题,实现了高精度表面形貌和接触电势差的联合成像。

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AI中文摘要

相关性纳米级表面表征受益于在同一环境中同时测量电子和结构性质,这对于现代材料科学和半导体失效分析至关重要。原位AFM-SEM测量通过自感知悬臂实现了巨大潜力;然而,由于其固有的电容交叉干扰而受到限制。在此,我们首次在扫描电子显微镜中实现了单次异步霍夫曼-凯尔文探针力显微镜的原位实施,使用压阻悬臂。我们通过解调激励和检测来克服压阻悬臂中普遍存在的电容交叉干扰,同时映射表面形貌和接触电势差,以与组成分析相关联。我们系统地比较了该异步技术的不同操作模式,阐明了其空间分辨率、信号灵敏度和信噪比。集成方法产生出色的信号质量和揭示了电子束扫描参数如何直接影响表面电势对比。我们在此相关分析流程上展示了二维异质结构和半导体电路。这项工作建立了一种稳健且多功能的相关成像模式,用于扫描电子显微镜中原位凯尔文力和形貌成像,用于下一代半导体器件分析和材料科学。

英文摘要

Correlative nanoscale surface characterization benefits from simultaneously measuring electronic and structural properties in the same environment, a capability that is essential for modern-day materials science and semiconductor failure analysis. In-situ AFM-SEM measurements facilitated by self-sensing cantilevers offer great potential here; however, they are limited due to their inherent capacitive crosstalk. Here, we demonstrate for the first time the in-situ implementation of single-pass heterodyne Kelvin probe force microscopy inside a scanning electron microscope, using piezo-resistive cantilevers. We overcome the capacitive crosstalk prevalent in piezo-resistive cantilevers by demodulating excitation and detection to simultaneously map surface topography and contact potential difference for correlation with compositional analysis. We systematically compare different operational modes of this heterodyne technique, elucidating their spatial resolution, signal sensitivity, and signal-to-noise ratio. The integrated approach yields exceptional signal quality and reveals how electron beam scan parameters can directly influence surface potential contrast. We demonstrate this correlative analysis workflow on two-dimensional heterostructures and semiconductor circuits. This work establishes a robust and versatile correlative imaging mode for in-situ Kelvin force and topography imaging inside a scanning electron microscope for next-generation semiconductor device analysis and materials science.

2605.16061 2026-05-18 cond-mat.mes-hall

Transport signatures of valley polarization in graphene multilayers: In-plane linear magnetoconductivity vs anomalous Hall effect

二维材料中谷极化传输特征:平面线性磁电导与反常霍尔效应

Fernando Peñaranda, Fernando de Juan

AI总结 研究二维材料中谷极化通过平面线性磁电导和反常霍尔效应的传输特征,揭示多层结构中谷极化与轨道磁矩的关系。

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AI中文摘要

在具有时间反演对称性关联的谷间相互作用费米口袋的二维材料中,自发的谷不平衡导致一种称为轨道磁体的新状态。由于时间反演对称性破缺,该状态可通过违反Onsager关系来探测,通常通过反常霍尔效应(AHE)实现。本文提出,奇场的平面线性磁电导(LMC)是谷极化的一种替代探测手段,即使AHE消失时也能发生。在多层结构中,该效应源于平面轨道矩和伯尔利曲率,由层间隧道效应产生,并主导于自旋响应。在分类众多近期研究的多层结构后,我们聚焦于两个谷极化例子:扭曲双层石墨烯,其中LMC非零但AHE消失除非有来自基底的额外对称性破缺;以及菱形石墨烯多层结构,其中LMC和AHE均跟踪谷极化,因为它们具有相同的对称性。通过自洽Hartree-Fock和半经典传输计算,我们对这两个例子进行了LMR的详细预测,并分析了对近期实验的启示。

英文摘要

In two-dimensional materials where interacting Fermi pockets occur in valleys related by time-reversal symmetry, a spontaneous valley imbalance results in a novel state known as an orbital magnet. Due to the breaking of time-reversal symmetry, this state can be probed in transport experiments by the violation of Onsager relations, most often done through the anomalous Hall effect (AHE). Here we propose that odd-in-field, in-plane linear magnetoconductivity (LMC) is an alternative probe of valley polarization which can occur even when the AHE vanishes. In multilayer structures, the effect originates from in-plane orbital moments and Berry curvatures enabled by interlayer tunneling and dominates over the spin response. After a classification of many recently studied multilayers, we focus on two valley polarized examples: twisted bilayer graphene, where LMC is finite but the AHE vanishes unless additional symmetry breaking from the substrate is present, and rhombohedral graphene multilayers, where LMC and AHE both track valley polarization because they have the same symmetry. Using self-consistent Hartree-Fock and semiclassical transport calculations, we present detailed predictions of LMR for these two examples and analyze the implications for recent experiments.

2605.16059 2026-05-18 cond-mat.str-el

Spherically symmetric approaches in the theoretical study of low-dimensional magnets

球对称方法在低维磁体理论研究中的应用

A. F. Barabanov, V. E. Valiulin, A. V. Mikheyenkov, P. S. Savchenkov

AI总结 本文介绍了一种球对称自洽方法及其相关算法,用于研究低维海森堡型自旋模型,包括反铁磁模型,考虑理论定理和自旋约束,避免传统分析中的困难,并应用于自旋-赝自旋模型及更复杂的构造。

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Journal ref
Phys. Usp. 69, 116-137 (2026)
AI中文摘要

本文阐述了球对称自洽方法及其相关理论算法的主要思想和重要结果。这些方法使得能够仔细考虑理论(Mermin-Wagner和Marshall)定理以及自旋位点约束,研究低维海森堡型自旋模型,包括反铁磁模型。从而避免了传统分析低维磁系统中的困难。该方法还可应用于自旋-赝自旋模型,并在考虑具有自由载流子的自旋模型时嵌入更复杂的构造,如基本和三带Hubbard模型、t-J和s-d模型以及Kondo晶格。

英文摘要

The main ideas and some of the most important results of the spherically symmetric self-consistent approach and a number of related theoretical algorithms are presented. These methods make it possible to study low-dimensional Heisenberg-type spin models, including frustrated ones, with careful consideration of the theoretic (Mermin-Wagner and Marshall) theorems, as well as the site spin constraint. Thus, the difficulties that may arise in the traditional analysis of low-dimensional magnetic systems are avoided. The approach can also be applied to the spin-pseudospin model, and is also embedded in more complex constructions when considering spin models with free carriers, such as the basic and three-band Hubbard models, t-J and s-d models, and the Kondo lattice.

2605.16058 2026-05-18 cs.DC cs.MS

High-Performance Star-M SVD for Big Data Compression

高性能的星-M SVD用于大数据压缩

Md Taufique Hussain, Grey Ballard, Aditya Devarakonda, Srinivas Eswar, Naman Pesricha, Vishwas Rao

AI总结 本文提出一种高效的共享内存并行解决方案,实现星-M SVD算法,提升大规模数据集的压缩性能和分析能力。

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AI中文摘要

在大数据时代,有效压缩大规模数据集并执行复杂数学运算至关重要。基于张量的分解方法相比传统矩阵方法在压缩能力上表现更优,且精度损失较小。在星-M张量框架下,张量可采用矩阵类比方式分解,包括使用星-M SVD。这种张量SVD具有最优性保证,并在特定类型的数据上表现出色,但软件实现多局限于面向生产的语言。本文提出了一种共享内存并行、高性能的解决方案,旨在高效实现底层算法。该软件将使大规模科学数据集的最优压缩成为可能,为增强数据分析和洞察开辟道路。

英文摘要

In the era of big data, effectively compressing large datasets while performing complex mathematical operations is crucial. Tensor-based decomposition methods have shown superior compression capabilities with minimal loss of accuracy compared to traditional matrix methods. Under the star-M tensor framework, tensors can be decomposed in a matrix-mimetic way, including using the star-M SVD. This tensor SVD has optimality guarantees and has shown exceptional performance on specific types of data, but software implementations have been mostly limited to productivity-oriented languages. In this work, we present our development of a shared-memory parallel, high-performance solution designed to efficiently implement the underlying algorithms. This software will enable optimal compression of extensive scientific datasets, paving the way for enhanced data analysis and insights.

2605.16057 2026-05-18 eess.SP

Holographic Airy Beamforming: Curved Trajectory Optimization for Blockage-Resilient Terahertz Communications

全息阿基米德波束成形:用于抗阻塞太赫兹通信的曲面轨迹优化

Xinyuan Hu, Boya Di, Lingyang Song

AI总结 本文提出基于幅度控制的全息阿基米德波束成形方案,利用可重构全息表面实现抗阻塞的太赫兹通信,通过优化轨迹提升被阻塞用户接收功率达10dB以上。

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AI中文摘要

太赫兹通信在6G网络中提供巨大的带宽,但近场区域由于大天线阵列面临严重的阻塞挑战。为克服近场聚焦束易受障碍物影响的限制,本文利用波前工程生成沿抛物线轨迹传播的阿基米德束以绕过阻塞。我们考虑可重构全息表面(RHS)作为精确波前工程的潜在解决方案,因其紧凑的辐射元件间距远小于半波长。我们揭示了RHS可调节的有效孔径允许抛物线偏移位于天线孔径内,从而增强设计阿基米德束轨迹的自由度。提出了一种名为基于幅度控制的全息阿基米德波束成形方案的模拟波束成形方法,以生成沿所需轨迹传播的弯曲束。为最大化被阻塞用户的接收功率,我们开发了一种基于几何的轨迹优化算法。仿真结果验证了与传统相控阵列相比,RHS可通过其可调节的有效孔径将被阻塞用户的接收功率提高超过10dB。

英文摘要

Terahertz communication offers vast bandwidth for high-speed transmission in the 6G networks but faces severe blockage challenges in the near-field region due to large antenna arrays. To overcome the limitation that near-field focused beams are susceptible to obstacles, wavefront engineering is leveraged to generate an Airy beam that propagates along a parabolic trajectory to circumvent blockages. In this paper, we consider the reconfigurable holographic surface (RHS) as a potential solution for such precise wavefront engineering owing to its compact radiation element spacing being much smaller than half-wavelength. We reveal that the adjustable effective aperture of the RHS allows the parabolic offset to be located within the antenna aperture, which enhances the freedom in designing Airy beam trajectories. An analog beamforming method, named the holographic Airy beamforming scheme based on amplitude control, is then proposed to generate the curved beam that propagates along the desired trajectory. To maximize the received power of a blocked user, we develop a geometry-based trajectory optimization algorithm. Simulation results validate that, compared to traditional phase-controlled arrays with analog beamforming, the RHS can leverage its adjustable effective aperture to improve the received power of the blocked user by over 10 dB.

2605.16055 2026-05-18 cond-mat.mtrl-sci

Fuzzy band structure of quantum dots by Bloch Orbital Expansion, unconventional insights into geometry-electronic structure relations

量子点的模糊能带结构:通过布洛赫轨道展开方法获得非传统几何-电子结构关系的见解

Zeger Hens, Jordi Llusar, Ivan Infante

AI总结 本文通过布洛赫轨道展开方法将量子点实空间轨道转换为动量空间,揭示了量子点几何与电子结构的关系,首次提出原子级核心/壳层量子点模型,明确了核心/壳层能带对齐。

Comments 34 Pages, 4 Figures, 1 Table

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Journal ref
ACS Nano 2025, 19, 8, 8227-8237
AI中文摘要

通过布洛赫轨道展开方法将量子点实空间轨道转换为动量空间,揭示了量子点几何与电子结构的关系,首次提出原子级核心/壳层量子点模型,明确了核心/壳层能带对齐。

英文摘要

The extension of ab-initio methods like density functional theory (DFT) to quantum dot (QD) geometries has enabled researchers to explore relationships between QD surface termination and electronic structure. However, fully utilizing the data from DFT requires novel classification methods for QD orbitals. Here, we identify relationships between QD geometry and electronic structure by transforming real-space QD orbitals into momentum-space using Bloch orbital expansion (BOE), yielding a fuzzy QD band structure. Comparing with bulk band structures, we show that truncated, unpassivated facets in III-V and II-VI QDs produce mid-gap orbitals derived from bulk surface orbitals; an identification challenging in real space. QDs with reconstructed facets, however, feature delocalized orbitals formed by superposition of bulk Bloch orbitals. Moreover, we prepare for the first time atomistic core/shell QD models and by the BOE expansion we can clearly identify the core/shell band alignment not possible in real space. These findings emphasize BOE as a vital tool for connecting computational and experimental insights in nanocrystal research.

2605.16053 2026-05-18 math.NT math.MG

Eisenstein circle packings and the Eisenpint Schmidt arrangement

Eisenstein 圆排列与 Eisenpint Schmidt 安排

James Rickards, Katherine E. Stange

AI总结 本文研究了Eisenstein圆排列的数论性质,包括二次型家族、强近似、同余障碍和局部-整体密度,揭示了Eisenpint Schmidt安排与Eisenstein圆排列之间的关系。

Comments 60 pages, 18 figures, 4 tables

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AI中文摘要

Imaginary quadratic number field K的Schmidt安排是扩展实线在PSL(2,O_K)作用下的轨道,作为扩展复平面上的莫比乌斯变换。当K≠Q(√-3)时,圆只能相切,导致各种整数圆排列,包括Apollonian圆排列。当K=Q(√-3)时,圆可相交于π/3和2π/3角度,导致难以从安排中提取圆排列。本文研究了称为

英文摘要

The Schmidt arrangement of an imaginary quadratic number field $K$ is the orbit of the extended real line under $\text{PSL}(2, \mathcal{O}_K)$ as Möbius transformations on the extended complex plane. If $K\neq\mathbb{Q}(\sqrt{-3})$, then the resulting set of circles can only intersect tangentially, leading to various classes of integral circle packings, including Apollonian circle packings. When $K=\mathbb{Q}(\sqrt{-3})$, circles can intersect at angles of $\fracπ{3}$ and $\frac{2π}{3}$, making it unclear how to extract circle packings from the arrangement. The goal of this paper is to study a modification of the $\mathbb{Q}(\sqrt{-3})-$Schmidt arrangement called the "Eisenpint Schmidt arrangement" and associated integral "Eisenstein circle packings". In analogy to the study of Apollonian circle packings, we study the number theory of such packings, including associated families of quadratic forms, show the Eisenpint Schmidt arrangement is formed of exactly all primitive Eisenstein circle packings, show strong approximation and classify congruence obstructions, prove a density-one local-global statement, and find quadratic -- but alas no cubic -- reciprocity obstructions. Unexpected aspects of the Eisenstein case include the role of congruence subgroups, the bipartite nature of the packings and reciprocity obstructions, the coefficients of quadratic obstructions, an abundance of extra symmetry, and the need to use "first-odd" quadratic forms.

2605.16051 2026-05-18 math.AG

Exponential concentration for quantum periods via mirror symmetry

通过镜像对称性研究量子周期的指数集中性

Jingwei Lu, Hua-Zhong Ke, Jianxun Hu

AI总结 本文研究满足指数集中性质的幂级数,证明修改后的超几何级数保持该性质,并证明当Fano流形具有非负系数的方便弱Landau-Ginzburg模型时,其量子周期也满足该性质。

Comments 19 pages. Comments are welcome!

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AI中文摘要

我们研究满足指数集中性质的幂级数,并证明适当的超几何级数修改保留该性质。作为几何应用,我们证明当流形具有方便的弱Landau-Ginzburg模型且系数非负时,Fano流形的量子周期也具有相同性质。

英文摘要

We investigate power series satisfying the exponential concentration property, and show that suitable modifications of hypergeometric series respect this property. As a geometric application, we prove that the quantum period of a Fano manifold possesses the same property, whenever the manifold admits a convenient weak Landau-Ginzburg model with non-negative coefficients.

2605.16050 2026-05-18 astro-ph.GA

The Low-$α$ Splash Population in the Milky Way

银河系中低α溅射人口

Lais Borbolato, João A. S. Amarante, Hélio D. Perottoni, Silvia Rossi, Victor P. Debattista, Zhao-Yu Li, Nathan Deg, Tigran Khachaturyants

AI总结 研究银河系中低α溅射人口的起源,发现其与盘星动态加热机制相关,通过模拟发现星系盘中星团形成是产生溅射人口的关键因素。

Comments Submitted to AAS Journals. Comments are welcome!

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AI中文摘要

银河系原位晕,也称为溅射,由年龄大于100亿年、金属丰度高([Fe/H] > -0.7)且高α值的恒星组成,即类似厚盘的化学特征,但轨道偏心率大于0.6。其起源与盘内恒星形成并由内部或外部因素加热有关。本文研究其低α对应物,即低α溅射,受近期发现的老薄盘人口启发。我们推测任何能加热盘星的机制都会影响现今高α和低α老人口。利用APOGEE DR17光谱学目录的数据,我们识别出金属丰富且具有类似经典高α溅射的晕样动力学特征的低α恒星。我们利用GASTRO模拟套件研究其可能的加热机制,探索星团形成以及类银河系类星系原盘中的重大并合的影响。我们的主要结果表明,只有包含星团的银河系模型才能通过早期银河系中星团的散射产生溅射人口,包括低α对应物,而仅包含并合且无早期星团阶段的模型无法产生这些人口。在模型中,低α溅射对应于一个被相同机制加热的老薄盘子集,该机制也负责高α溅射的形成。

英文摘要

The Milky Way in-situ halo, also known as the Splash, consists of old (Age $>$ 10 Gyr), metal-rich ([Fe/H] $> -0.7$), high-$α$ stars, i.e., thick disk-like chemistry, on halo-like orbits (eccentricity > 0.6). Its origin is linked to stars formed in the disk and dynamically heated by either internal or external agents. In this work, we investigate its low-$α$ counterpart, the low-$α$ Splash, motivated by recent findings of an old thin disk population. We conjecture that any mechanism capable of heating disk stars should affect both of present-day high- and low-$α$ old populations. Using data from the APOGEE DR17 spectroscopic catalog, we identify metal-rich low-$α$ stars with halo-like kinematics similar to those of the classical high-$α$ Splash. We investigate their possible heating mechanisms using the GASTRO suite of simulations, which allows us to explore the effects of star-forming clumps as well as a major merger in the proto-disk of a Milky Way analog galaxy. Our main results show that only clumpy Milky Way models are able to produce Splash populations through scattering by clumps in the early Galaxy, including the low-$α$ counterpart, whereas the model including only the merger and without an early clumpy phase fails to produce these populations. In the models, the low-$α$ Splash corresponds to a subset of the old thin disk that was dynamically heated by the same mechanism responsible for the formation of the high-$α$ Splash.

2605.16049 2026-05-18 math.DS math.AP q-bio.MN

Conditions for spatial instabilities and pattern formation from monomial steady state parameterizations

空间不稳定性及图案形成的条件:基于单项稳态参数化

Carsten Conradi, Maya Mincheva, Hannes Uecker

AI总结 研究反应网络中空间不稳定性起始条件,基于均匀系统稳态参数化,推导特征多项式系数符号决定Turing不稳定性的条件,并提出触发此不稳定的域大小要求。

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AI中文摘要

我们研究了在反应网络中空间不稳定性起始的条件,其中均匀系统具有稳态参数化。我们推导了一个充分条件——基于线性化雅可比矩阵特征多项式常数项和主系数符号,以及扩散系数缩放后的符号——以保证在适当选择的域Ω上出现类似于Turing的不稳定性。我们还提出了触发此不稳定性所需的具体域大小|Ω|条件。由于使用单项参数化,这些条件表现为仅涉及速率常数和扩散系数的代数多项式不等式。我们将这些思想应用于描述蛋白质在两个结合位点上顺序和分布性(去)磷酸化的网络,最终推导出一个仅涉及四种酶的催化常数和四种酶-底物复合物扩散系数的条件,以保证Turing-like不稳定性。

英文摘要

We study the onset of spatial instabilities in reaction networks where the spatially homogeneous system admits a steady state parameterization. We formulate a sufficient condition -- based on the signs of the constant and leading coefficients of the characteristic polynomial of the linearized Jacobian scaled by the diffusion coefficients -- that guarantees a Turing-like instability to spatially inhomogeneous solutions on appropriately chosen domains $Ω$. We also present a specific condition on the domain size $|Ω|$ required to trigger this instability. As a consequence of employing a monomial parameterization, these conditions take the form of algebraic polynomial inequalities involving only rate constants and diffusion coefficients. We apply these ideas to a network describing the sequential and distributive (de-)phosphorylation of a protein at two binding sites, ultimately deriving a condition involving only the four catalytic constants of the enzymes and the diffusion coefficients of the four enzyme-substrate complexes that guarantees a Turing-like instability.

2605.16040 2026-05-18 math.AG math.SG

Homological Mirror Symmetry for Conic Bundle

锥面包层的同调镜像对称

Bohan Fang, Yuze Sun, Peng Zhou

AI总结 本文研究了锥面包层的同调镜像对称,通过A侧的Hori-Vafa镜像和B侧的toric Calabi-Yau流形,证明了微局域范畴与coherent sheaf的等价性,并扩展了特征循环的定义。

Comments 27 pages, 1 figure

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AI中文摘要

我们研究了同调镜像对称陈述,其中A侧是锥面包层Hori-Vafa镜像$\mathcal{Y} = \{uv = f(z)\} \subset \mathbb{C}^2 \times (\mathbb{C}^\ast)^n$,对于一个Laurent多项式$f$在$(\mathbb{C}^\ast)^n$中,B侧是某些toric Calabi-Yau$(n+2)$-fold,其光滑反canonical除子被移除$\mathcal{X}^\circ = \mathcal{X} \setminus w^{-1}(-1)$。我们证明当$\mathcal{X}$是toric Fano $n$-orbifold $S$的canonical bundle,并且$f$是其Givental超势能时,$\mathcal{Y}$的强变形退缩骨架$\mathsf{L}$在RSTZ的意义下有Weinstein邻域$U$,使得wrapped microlocal sheaf category $μ\mathrm{Sh}^w_{\mathsf{L}}(\mathsf{L}) \cong \mathrm{Coh}(\mathcal{X}^\circ)$。这证明了Abouzaid-Auroux-Katzarkov在Publ. math. IHÉS 123(1):199--282, 2016, Thm. 1.7中的微局域范畴版本的SYZ镜像。我们还扩展了Kashiwara-Schapira在Sheaves on Manifolds, Grundlehren math. Wiss. 292, Springer, 1990, Ch. IX中的构造可取sheaf的特征循环定义到有限秩对象在$μ\mathrm{Sh}^w_{\mathsf{L}}(\mathsf{L})$中,并描述了与coherent sheaf支持在$S$上的对象的特征循环。

英文摘要

We study the homological mirror symmetry statement where A-side is the conic bundle Hori--Vafa mirror $\mathcal{Y} = \{uv = f(z)\} \subset \mathbb{C}^2 \times (\mathbb{C}^\ast)^n$ for a Laurent polynomial $f$ in $(\mathbb{C}^\ast)^n$, and B-side is some a toric Calabi--Yau $(n+2)$-fold with a smooth anti-canonical divisor removed $\mathcal{X}^\circ = \mathcal{X} \setminus w^{-1}(-1)$. We show that when $\mathcal{X}$ is the canonical bundle of a toric Fano $n$-orbifold $S$ and $f$ is its Givental superpotential, the strong deformation retraction skeleton $\mathsf{L}$ of $\mathcal{Y}$ in the sense of RSTZ (Ruddat--Sibilla--Treumann--Zaslow in Geom. Topol. 18(3):1343--1395, 2014) has a Weinstein neighborhood $U$, such that the wrapped microlocal sheaf category $μ\mathrm{Sh}^w_{\mathsf{L}}(\mathsf{L}) \cong \mathrm{Coh}(\mathcal{X}^\circ)$. This proves a microlocal categorical version of the SYZ mirror in (Abouzaid--Auroux--Katzarkov in Publ. math. IHÉS 123(1):199--282, 2016, Thm. 1.7). We also extend the definition of characteristic cycles for constructible sheaves in cotangent bundles from (Kashiwara--Schapira in Sheaves on Manifolds, Grundlehren math. Wiss. 292, Springer, 1990, Ch. IX) to finite-rank objects in $μ\mathrm{Sh}^w_{\mathsf{L}}(\mathsf{L})$, and describe the characteristic cycles for objects mirror to a coherent sheaf supported on $S$.