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2605.30828 2026-06-01 nucl-th

Dynamical selection of fragment shell effects in spontaneous fission of $^{240}$Pu, $^{232}$Th, and $^{264}$Fm

$^{240}$Pu、$^{232}$Th 和 $^{264}$Fm 自发裂变中碎片壳效应的动力学选择

Qiafeng Chen, Fuchang Gu, Yingge Huang, Erxi Xiao, Yinu Zhang, Jun Su

AI总结 通过结合微观集体动力学和碎片壳分析,研究 $^{240}$Pu、$^{232}$Th 和 $^{264}$Fm 自发裂变中碎片壳效应如何影响质量产额,发现增强产额源于动力学布居的裂变构型与碎片壳结构之间的相干重叠。

Comments 12 pages, 9 figures, comments and suggestions are welcome

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AI中文摘要

理解碎片壳效应如何影响自发裂变质量产额仍然是核裂变理论的核心挑战。本工作通过结合微观集体动力学和碎片壳分析,研究了 $^{240}$Pu、$^{232}$Th 和 $^{264}$Fm 自发裂变中壳效应的作用。采用两步框架:首先,利用 Wentzel-Kramers-Brillouin 近似沿约束 Hartree-Fock-Bogoliubov 理论计算的势能面上的最小作用路径描述从内转折点到外转折点的隧穿。其次,通过 Langevin 动力学在四极和八极变形的大集体空间中模拟从外转折点到断裂点的耗散下降。利用从 Langevin 断裂构型中提取的代表性偶偶碎片对的平滑能级密度指标量化碎片壳效应。分析表明,增强产额源于动力学布居的断裂构型、碎片势能面上的低能区域以及费米面附近低中子和/或质子能级密度之间的相干重叠。质子壳效应在不对称道中的轻碎片和重碎片中均提供持久的微观选择性,而中子壳效应提供额外的稳定性。有限四极和八极变形下的形变壳效应在稳定不对称裂变道中起关键作用。本工作表明,裂变碎片产额反映了由势能面拓扑结构提供可及性并由随机动力学布居的壳有利构型,其中最大产额对应于壳间隙提供最大束缚能的构型。

英文摘要

Understanding how fragment shell effects influence spontaneous fission mass yields remains a central challenge in nuclear fission theory. This work investigates the role of shell effects in the spontaneous fission of $^{240}$Pu, $^{232}$Th, and $^{264}$Fm by combining microscopic collective dynamics with fragment-level shell analysis. A two-step framework is employed: first, the tunneling from the inner to outer turning points is described using the Wentzel-Kramers-Brillouin approximation along the least-action path on a potential energy surface calculated from constrained Hartree-Fock-Bogoliubov theory. Second, the dissipative descent from the outer turning points to scission is simulated via Langevin dynamics in a large collective space of quadrupole and octupole deformations. Fragment shell effects are quantified using smoothed level density indicators for representative even-even fragment pairs extracted from Langevin scission configurations. The analysis reveals that enhanced yields arise from a coherent overlap among dynamically populated scission configurations, low-energy regions on the fragment potential energy surfaces, and low neutron and/or proton level densities near the Fermi surface. Proton shell effects provide persistent microscopic selectivity in both light and heavy fragments across asymmetric channels, while neutron shell effects offer additional stabilization. Deformed shell effects at finite quadrupole and octupole deformations play a crucial role in stabilizing asymmetric fission channels. This work demonstrates that fission fragment yields reflect shell-favored configurations that are made accessible by the potential energy surface topology and populated by stochastic dynamics, with the largest yields corresponding to configurations where shell gaps provide maximal binding.

2605.30827 2026-06-01 math.NA cs.NA

A Multi-Invariant Preserving Discrete Gradient Methods

多不变量保持的离散梯度方法

Haodong Pu, Maohua Ran

AI总结 提出一种基于预测-校正策略的结构保持方法,通过离散梯度校正显式单步或多步格式的预测值,同时保持多个非线性不变量并维持原预测器的精度阶。

Comments 19 pages,13 figures and 4 tables

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AI中文摘要

本文介绍了一种新颖的保守系统结构保持方法,基于预测-校正策略。该框架对显式单步或多步格式生成的预测值应用离散梯度校正,在保持非线性不变量的同时维持原预测器的精度阶。该方法自然地扩展到需要同时守恒多个不变量的情形。在温和条件下,建立了守恒性、可解性、数值精度和稳定性。在Lotka-Volterra系统、sine-Gordon方程、刚体动力学和Kepler问题上的长期数值模拟表明,与现有的投影和松弛方法相比,该方法具有更好的鲁棒性和守恒性。

英文摘要

This work introduces a novel structure-preserving methods for conservative systems based on a predictor-corrector strategy. The framework applies a discrete gradient correction to predictions generated by explicit one-step or multi-step schemes, which preserves nonlinear invariants while maintaining the accuracy order of the original predictor. This approach extends naturally to problems requiring simultaneous conservation of multiple invariants. Under mild conditions, conservation properties, solvability, numerical accuracy, and stability are established. Long-term numerical simulations on Lotka-Volterra systems, sine-Gordon equations, rigid body dynamics, and Kepler problems demonstrate improved robustness and conservation properties compared to existing projection and relaxation methods.

2605.30822 2026-06-01 cond-mat.dis-nn cond-mat.soft

Using graph neural networks to predict many-body interactions in amorphous materials

使用图神经网络预测非晶材料中的多体相互作用

Mehryar Jannesari Ghomsheh, Donald L. Koch, Sarah Hormozi

AI总结 本文使用等变消息传递图神经网络NequIP学习无溶剂聚合物接枝纳米颗粒模型软玻璃的高维势能面,以远低于经典密度泛函理论的计算成本准确预测多体相互作用,并通过蒙特卡洛模拟重现实验平衡结构。

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AI中文摘要

多体相互作用支配着许多非晶材料的复杂行为,从金属玻璃到生物组织,但为了计算效率,通常被成对加和框架所取代。在这里,我们使用经典密度泛函理论(DFT)研究无溶剂聚合物接枝纳米颗粒(PGNs)的模型软玻璃,其中没有溶剂迫使接枝链均匀填充间隙空间,在核心之间产生强烈的角度依赖性多体相互作用。我们展示了NequIP,一种等变消息传递图神经网络(GNN),学习了系统的高维、崎岖势能面,并以四个数量级更低的成本在PGN设计参数范围内重现了经典DFT能量。对GNN超参数的系统分析提供了对相互作用范围、各向异性和有效体阶的物理洞察。GNN驱动的蒙特卡洛模拟揭示了平衡状态下局部有利的二十面体样结构,并且引人注目的是,尽管网络仅在高能、非平衡构型上训练,但恢复了与实验一致的平衡结构。

英文摘要

Many-body interactions govern the complex behavior of many amorphous materials, from metallic glasses to biological tissues, yet are often replaced by pairwise additive frameworks for computational efficiency. Here, we use classical density functional theory (DFT) to study a model soft glass of solvent-free polymer-grafted nanoparticles (PGNs), where the absence of solvent forces grafted chains to uniformly fill the interstitial space, generating strong angular-dependent many-body interactions between the cores. We show that NequIP, an equivariant message-passing graph neural network (GNN), learns the high-dimensional, rugged potential energy landscape of the system and reproduces classical DFT energies across a range of PGN design parameters at four orders of magnitude lower cost. Systematic analysis of GNN hyperparameters offers physical insights into the range, anisotropy, and effective body order of interactions. GNN-driven Monte Carlo simulations reveal locally favored icosahedral-like structures at equilibrium, and strikingly, recover equilibrium structures in agreement with experiments, despite the network being trained only on high-energy, out-of-equilibrium configurations.

2605.30821 2026-06-01 math.CO

The spectral inducibility of graphs

图的谱诱导性

Liying Kang, Xizhi Liu, Yongchun Lu

AI总结 引入图的谱诱导性问题,通过谱半径度量诱导子图计数,并证明完全多部图在谱极值中的最优性。

Comments 14 Pages

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AI中文摘要

我们引入了经典诱导性问题的谱版本。给定一个ℓ-顶点图F和一个n-顶点图G,令H_F(G)为ℓ-一致超图,其边是在G中诱导出F的副本的ℓ-集合。我们研究在所有n-顶点图G上H_F(G)的最大可能α-谱半径。对于固定的G,当α→∞时,该谱参数趋于ℓ!乘以G中F的诱导副本数,因此细化了通常的诱导副本计数。我们的主要结果是Brown-Sidorenko约化的谱类比:对于每个完全多部图F,每个n,以及每个α≥1,谱极值图可以选择为完全多部图。我们还证明了领先的渐近常数是普通的诱导性i(F),并得到了星图K_{1,t}和平衡完全r-部图K_{a,…,a}(其中r≤2^a-1)的精确多部约化。

英文摘要

We introduce a spectral version of the classical inducibility problem. Given an $\ell$-vertex graph $F$ and an $n$-vertex graph $G$, let $H_F(G)$ be the $\ell$-uniform hypergraph whose edges are the $\ell$-sets inducing a copy of $F$ in $G$. We study the maximum possible $α$-spectral radius of $H_F(G)$ over all $n$-vertex graphs $G$. For fixed $G$, this spectral parameter tends to $\ell!$ times the number of induced copies of $F$ in $G$ as $α\to\infty$, and therefore refines the usual induced-copy count. Our main result is a spectral analogue of the Brown--Sidorenko reduction: for every complete multipartite graph $F$, every $n$, and every $α\ge1$, a spectral extremal graph can be chosen to be complete multipartite. We also show that the leading asymptotic constant is the ordinary inducibility $i(F)$, and obtain exact multipartite reductions for stars $K_{1,t}$ and balanced complete $r$-partite graphs $K_{a,\ldots,a}$ with $r\le 2^a-1$.

2605.30820 2026-06-01 physics.optics physics.app-ph

Binary Amplitude Modulation Suppresses Noise Up-Conversion in Coherent Diffractive Optical Networks

二元振幅调制抑制相干衍射光学网络中的噪声上转换

Hyuntae Lim, Kyoungsik Kim

AI总结 本文提出在相干波光计算中,将调制流形从连续复值限制为二元振幅可抑制随机噪声上转换并保持分类保真度,通过理论分析和实验验证了二元振幅掩模D2NN在噪声鲁棒性上的优势。

Comments 14 pages, 5 figures

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AI中文摘要

我们在相干波光计算中建立了一个基本原理:将调制流形从连续复值限制为二元振幅,可在保持分类保真度的同时抑制随机噪声上转换,产生一种反直觉的“少即是多”鲁棒性定律。七层二元振幅掩模D2NN(BM-D2NN)在MNIST和Fashion-MNIST上分别达到90.9%和81.9%的测试准确率,与连续调制D2NN(C-D2NN)相差2~4个百分点。在像素级高斯噪声N(m,σ²)下,涵盖零均值(散粒噪声)到非零均值(热/读出噪声)区域,BM-D2NN比C-D2NN的准确率高出最多32.8个百分点(MNIST)和18.5个百分点(Fashion-MNIST)。我们解析推导了一个噪声贡献度量C,由仅从干净数据可计算的透射偏置因子K控制,且对于二元调制始终小于连续调制(对所有测试样本验证),从而无需噪声模拟即可保证鲁棒性排序。此外,对于干净数据输入,BM-D2NN的成像面强度提高了6.79倍。这些结果建立了一个连接调制流形几何与噪声鲁棒性的定量物理原理,适用于z/λ >> 1区域内的任何相干光学处理器。

英文摘要

We establish a fundamental principle in coherent wave-optical computing: restricting the modulation manifold from continuous complex-valued to binary amplitude suppresses stochastic-noise up-conversion while preserving classification fidelity, yielding a counter-intuitive less-is-more robustness law. Seven-layer binary-amplitude-mask D2NN (BM-D2NN) achieve 90.9% (MNIST) and 81.9% (Fashion-MNIST) test accuracy, within 2~4 pp of continuous-modulation D2NN (C-D2NN). Under pixel-wise Gaussian noise N(m,σ^2), spanning zero-mean (shot noise) to nonzero-mean (thermal/readout) regimes, BM-D2NN outperform C-D2NN by up to 32.8 pp (MNIST) and 18.5 pp (Fashion-MNIST). We analytically derive a noise-contribution metric C, governed by a transmission-bias factor K computable from clean data alone, that is consistently smaller for binary modulation than for continuous modulation (as verified for all test samples), guaranteeing the robustness ordering without noisy simulation. BM-D2NN additionally deliver a 6.79-fold higher imaging-plane intensity for clean data input. These results establish a quantitative physical principle connecting modulation-manifold geometry to noise robustness, applicable to any coherent optical processor in the z/λ >> 1 regime.

2605.30817 2026-06-01 math.GT

Boundedness of Dehn surgery slopes admitting hyperbolic $\mathrm{PSL}(2,\mathbb{R})$-representations for two-bridge knots

双桥结的Dehn手术斜率有界性:承认双曲$\mathrm{PSL}(2,\mathbb{R})$表示

Shunjiang Jiang, Ran Tao

AI总结 本文研究双桥结的Dehn填充,通过非交换$\mathrm{PSL}(2,\mathbb{R})$表示,证明了对于每个非平凡双桥结,承认具有双曲子午线像的表示的斜率集有界,即绝对值足够大的斜率对应的Dehn填充不承认此类表示。

Comments 14 pages, comments are welcome

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AI中文摘要

我们通过非交换表示进入$\mathrm{PSL}(2,\mathbb{R})$研究双桥结上的Dehn填充,其中子午线像是双曲的。对于每个固定的非平凡双桥结,我们证明了承认此类表示的手术斜率集是有界的。等价地,沿具有足够大绝对值的斜率的Dehn填充不承认具有双曲子午线像的非交换$\mathrm{PSL}(2,\mathbb{R})$表示。证明结合了Riley多项式和Khoi的手术斜率公式。在每个允许的实代数分支上,我们将子午线和经线平移参数表示为分支参数的函数,并为其商推导出统一的端点估计。得到的界原则上是有效的但未优化。我们还提供了说明参数集和端点行为的例子。

英文摘要

We study Dehn fillings on two-bridge knots via non-abelian representations into $\mathrm{PSL}(2,\mathbb{R})$ whose meridian image is hyperbolic. For each fixed nontrivial two-bridge knot, we prove that the set of surgery slopes admitting such representations is bounded. Equivalently, Dehn fillings along slopes with sufficiently large absolute value admit no non-abelian $\mathrm{PSL}(2,\mathbb{R})$ representations with hyperbolic meridian image. The proof combines the Riley polynomial with Khoi's surgery-slope formula. On each admissible real algebraic branch, we express the meridian and longitude translation parameters as functions of the branch parameter and derive uniform endpoint estimates for their quotient. The resulting bound is effective in principle but not optimized. We also provide examples illustrating the parameter sets and endpoint behavior.

2605.30816 2026-06-01 hep-ph nucl-th

Functional renormalization group study of the jet quenching parameter near the QCD critical end point

QCD临界终点附近喷注淬灭参数的功能重正化群研究

Yi-zhen Huang, Shi Yin, Sheng-nan Han, Jing Wu, Feng Li, Wei-jie Fu

AI总结 利用功能重正化群,在QCD相图中研究喷注淬灭参数,发现其在手征相变边界上方有显著贡献,并在大重子化学势下因临界终点附近手征交叉变锐而增强,与部分子临界乳光现象一致。

Comments 12 pages, 5 figures

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AI中文摘要

我们在QCD辅助的低能有效理论中,利用功能重正化群(fRG)研究了QCD相图中的喷注淬灭参数$\hat{q}$。根据将$\hat{q}$与手征序参量场的谱函数联系起来的公式,我们从解析延拓的介子两点函数计算了有限温度和重子化学势下$\sigma$和$\pi$介子对$\hat{q}$的贡献。我们发现,$\hat{q}$主要在手征相边界上方有显著贡献,并且随着手征交叉向临界终点(CEP)变锐,在大重子化学势下表现出明显的增强,这一行为与部分子临界乳光(PCO)的图像一致,即由临界$\sigma$场涨落引起的喷注横向动量展宽的显著增强。

英文摘要

We investigate the jet quenching parameter $\hat{q}$ in the QCD phase diagram within a QCD-assisted low-energy effective theory using the functional renormalization group (fRG). Following the formalism that relates $\hat{q}$ to the spectral functions of the chiral order-parameter field, we compute the $σ$ and $π$ meson contributions to $\hat{q}$ at finite temperature and baryon chemical potential from analytically continued mesonic two-point functions. We find that $\hat{q}$ receives appreciable contributions mainly above the chiral phase boundary and exhibits a pronounced enhancement at large baryon chemical potential as the chiral crossover sharpens toward the critical end point (CEP), a behavior consistent with the picture of partonic critical opalescence (PCO), a pronounced enhancement of jet transverse momentum broadening induced by the critical $σ$ field fluctuations.

2605.30815 2026-06-01 quant-ph physics.atom-ph

Dissipative generation of spin squeezing in the resolved vacuum Rabi splitting limit

在分辨真空拉比分裂极限下自旋压缩的耗散生成

Edwin Chaparro, Eric Yilun Song, Diego Barberena, James K. Thompson, Ana Maria Rey, Jeremy T. Young

AI总结 本文研究在分辨真空拉比分裂区域中,通过对称性保护的耗散动力学实现自旋压缩,展示了超过25 dB的压缩和接近理想单轴扭转标度,为光钟平台超越标准量子极限提供了实用途径。

Comments 29 pages, 10 figures

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AI中文摘要

利用存在强对称性时的耗散最近成为在原子钟中产生纠缠的一种有前途的途径。然而,先前的提议依赖于腔光子可以被绝热消除的机制,这显著限制了它们对处于或接近分辨真空拉比分裂区域的实验相关腔QED机制的适用性。在这里,我们表明即使当腔光子积极参与动力学时,对称性保护的耗散自旋压缩也可以实现,从而扩展了该协议的实验相关性。我们研究了在分辨真空拉比分裂区域中耦合到光学腔的$^{87}\mathrm{Sr}$原子的三能级系综,并证明,通过驱动幅度和失谐的平滑斜坡,驱动-耗散动力学进入一个稳定的低光子区域,在该区域中非绝热腔激发和区分扇区的光子泄漏可以被控制。在这个低光子操作窗口内,区分扇区的光子泄漏被抑制,并且扇区依赖的几何相位实现了有效的单轴扭转。在协议结束时,通过关闭驱动,纠缠也可以被有效地直接转移到长寿命的钟态上。对于实验上现实的参数,我们从理论上表明,对于$10^5$个原子,可以产生超过$25\,\mathrm{dB}$的压缩,接近理想单轴扭转标度$\xi_{\min}^2 \propto N^{-2/3}$。在固定协同性下,优化的压缩与未分辨区域实现大致相当,而分辨区域实现则在更短的时间尺度上达到相当的压缩。这些结果确立了对称性保护的耗散动力学作为在光钟平台上实现超越标准量子极限性能的实用途径。

英文摘要

Harnessing dissipation in the presence of strong symmetries has recently emerged as a promising route for generating entanglement in atomic clocks. However, previous proposals relied on regimes where cavity photons can be adiabatically eliminated, significantly limiting their applicability to experimentally relevant cavity-QED regimes that lie in or near the resolved vacuum Rabi splitting regime. Here we show that symmetry-protected dissipative spin squeezing can be realized even when cavity photons actively participate in the dynamics, extending the experimental relevance of the protocol. We study a three-level ensemble of $^{87}\mathrm{Sr}$ atoms coupled to an optical cavity in the resolved vacuum Rabi splitting regime and demonstrate that, with smooth ramps of the drive amplitude and detunings, the driven-dissipative dynamics enters a stable low-photon regime in which nonadiabatic cavity excitations and sector-resolving photon leakage can be controlled. Within this low-photon operating window, sector-resolving photon leakage is suppressed and the sector-dependent geometric phase realizes effective one-axis twisting. At the end of the protocol the entanglement can also be efficiently transferred directly onto the long-lived clock states by turning the drive off. For experimentally realistic parameters, we theoretically show that more than $25\,\mathrm{dB}$ of squeezing can be generated for $10^5$ atoms, closely saturating the ideal one-axis twisting scaling $ξ_{\min}^2 \propto N^{-2/3}$. At fixed cooperativity, the optimized squeezing remains broadly comparable to the unresolved-regime implementation, while the resolved-regime implementation reaches comparable squeezing on a substantially shorter physical timescale. These results establish symmetry-protected dissipative dynamics as a practical route to beyond the standard-quantum-limit performance in optical-clock platforms.

2605.30814 2026-06-01 cs.AR

A Reconfigurable Computing In-Memory Macro with Charge-sharing-based Weighted Accumulator

基于电荷共享加权累加器的可重构存内计算宏

Junyi Yang, Shuai Dong, Zhengnan Fu, Hongyang Shang, Arindam Basu

AI总结 针对SRAM模拟存内计算中的ADC开销大、多比特输入延迟高和读取位线电压受限问题,提出一种支持1-7b输入、2-4b权重和1-7b输出的256x128可重构存内计算阵列,通过IMADC、BSCHA和dual-8T bitcell三项创新实现高效计算。

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AI中文摘要

基于SRAM的模拟存内计算展示了出色的效率。然而,它面临三个关键挑战:显著的ADC开销、多比特输入的高延迟以及有限的读取位线电压。为了解决这些问题,本文提出了一种多比特高度可重构的256x128存内计算阵列,支持1-7b输入、2-4b权重和1-7b输出。引入了三项关键创新:1) IMADC仅占用3%的面积开销,相比之前的IMADC实现了9倍的改进;2) BSCHA相比传统的脉宽调制(PWM)和位切片模式分别将延迟降低了1.9倍和6.6倍;3) 一种双8T位单元,通过解耦读取路径实现三元权重存储,并结合读取字线欠驱动共源共栅技术,将单位放电电流的线性度提高了7倍,并将可用读取位线电压提高了3.5倍。

英文摘要

SRAM-based analog computing-in-memory demonstrates outstanding efficiency. However, it faces three critical challenges: significant ADC overhead, high latency for multi-bit inputs, and limited read bitline voltage. To address these issues, this work proposes a multi-bit highly reconfigurable 256x128 in-memory computing array supporting 1-7b input, 2-4b weight, and 1-7b output. Three key innovations are introduced: 1) The IMADC occupies only 3% area overhead, achieving a 9x improvement compared to previous IMADC; 2) The BSCHA reduces latency by 1.9x and 6.6x compared to traditional pulse-width modulation (PWM) and bit-slicing modes, respectively; 3) A dual-8T bitcell enabling ternary weight storage through a decoupled read path, integrated with a read wordline under-driven cascode technique, improves linearity of unit discharge current by 7x and increases the usable read bitline voltage by 3.5x.

2605.30809 2026-06-01 cs.NI

Stratifying the Digital Divide: Analysis of Socio-Economic Influences on Internet Performance

数字鸿沟分层:社会经济因素对互联网性能影响的分析

Shivani Kalamadi, Aditya Bej, Sachin Kumar Singh, Varshika Srinivasavaradhan, Elizabeth Belding, Alexander Gamero-Garrido

AI总结 通过配对约1.7亿次Ookla速度测试与美国人口普查数据,利用随机森林回归识别下载/上传速度和延迟的社会经济驱动因素,发现人口密度影响是尺度假象,而收入与种族构成是城市环境中互联网质量的主要决定因素。

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AI中文摘要

尽管技术进步众多,数字鸿沟仍然是一个影响全球数百万人的紧迫问题。我们提出了一个在人口普查区块组层面诊断互联网不平等的框架,通过将大约1.7亿次众包Ookla速度测试(2021-2025年)与六个大都市地区的美国人口普查人口统计数据配对。在量化并纠正抽样偏差后,我们使用带有排列重要性的随机森林回归来识别下载速度、上传速度和延迟的社会经济驱动因素。人口密度在区域层面主导所有三个指标,但这种主导是尺度的假象:一旦将区域按密度分层,其影响在中高密度社区中消失,揭示出社会经济条件才是大多数城市环境中互联网质量的真正区分因素。在控制密度后,收入和种族构成成为主要驱动因素,收入始终决定上传速度,而种族构成被证明是比收入或教育更强的下载速度预测因子。我们的发现表明,互联网不平等是局部配置的:没有单一的全国性叙事可以解释它,有效的政策需要针对特定区域的干预。

英文摘要

Despite numerous technological advancements, the digital divide remains a pressing issue affecting millions worldwide. We present a framework for diagnosing internet inequality at the Census Block Group level by pairing approximately 170 million crowdsourced Ookla speed tests (2021--2025) with U.S. Census demographics across six metropolitan regions. After quantifying and correcting for sampling bias, we use Random Forest regression with permutation importance to identify the socio-economic drivers of download speed, upload speed, and latency. Population density dominates all three metrics at the regional level, but this dominance is an artifact of scale: once areas are stratified into density bins, its influence vanishes in medium- and higher-density neighborhoods, revealing that socio-economic conditions are the true differentiators of internet quality in most urban settings. After controlling for density, income and racial composition emerge as the primary drivers, income consistently dictating upload speed and racial composition proving to be a stronger predictor of download speed than either income or education. Our findings demonstrate that internet inequality is locally configured: no single national narrative explains it, and effective policy demands region-specific intervention.

2605.30805 2026-06-01 physics.flu-dyn cs.NA math.NA

A scalable Ewald-free BIE framework for periodic Stokes flow via hierarchical proxy sums

一种基于层次代理求和的周期性斯托克斯流可扩展无Ewald边界积分方程框架

Tianyue Li, Dhairya Malhotra, Shravan Veerapaneni

AI总结 提出一种仅使用自由空间格林函数、避免Ewald求和与扩展线性系统的边界积分方程框架,通过层次代理求和实现周期性斯托克斯流的高阶精度O(N)计算。

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AI中文摘要

受限周期性几何中的颗粒斯托克斯流是生物物理、微流体和复杂流体流变学中广泛问题的基础。边界积分方程(BIE)方法是解决此类问题的自然工具,但现有的周期化方案要么依赖于周期性格林函数(对复杂约束几何具有限制性),要么依赖于自由空间方案,这些方案在扩展线性系统中除了表面密度外还求解辅助代理强度,其成本在三维中扩展不利。我们提出了一种用于三维颗粒斯托克斯流的BIE框架,适用于圆形截面周期性管道、壁面约束双周期和三周期几何,仅使用自由空间格林函数,避免了Ewald求和和扩展线性系统。代理源放置在核无关快速多极方法(KIFMM)的等效表面上形成辅助基,远图像盒的贡献通过层次代理求和捕获,该求和通过净力为零的相容性条件实现绝对收敛。得到的周期化预计算仅依赖于周期盒几何,与核及盒内表面无关,并且对斯托克斯流、应力流和旋转流直接复用。结合高阶自适应表面离散化,该方法在近场使用单层图像盒时实现了O(N)成本的高阶精度。在具有数千个颗粒的密集多分散悬浮液和复杂周期性通道流动上的数值示例,以及强扩展和弱扩展研究,展示了在分布式内存架构上处理数百万自由度系统的高效性能。

英文摘要

Particulate Stokes flow in confined, periodic geometries underlies a broad class of problems in biophysics, microfluidics, and the rheology of complex fluids. Boundary integral equation (BIE) methods are a natural tool for such problems, but existing periodization schemes rely either on periodic Green's functions, which are restrictive for complex confining geometries, or on free-space schemes that solve auxiliary proxy strengths alongside the surface densities in an extended linear system whose cost scales unfavorably in three dimensions. We present a BIE framework for three-dimensional particulate Stokes flow in periodic pipes with circular cross-sections, wall-bounded doubly-periodic, and triply-periodic geometries that uses only the free-space Green's function and avoids both Ewald summation and the extended linear system. Proxy sources placed on equivalent surfaces of the kernel-independent FMM (KIFMM) form the auxiliary basis, and contributions from far image boxes are captured by a hierarchical proxy sum made absolutely convergent by a net-force-zero compatibility condition. The resulting periodization precomputation depends only on the periodic-box geometry, independent of the kernel and of the surfaces inside the box, and is reused verbatim across the Stokeslet, stresslet, and rotlet. Combined with high-order adaptive surface discretizations, the method achieves high-order accuracy at $\mathcal{O}(N)$ cost with a single layer of image boxes in the near field. Numerical examples on dense polydisperse suspensions with thousands of particles and on flow through complex periodic channels, together with strong and weak scaling studies, demonstrate efficient performance on systems with millions of degrees of freedom on distributed-memory architectures.

2605.30801 2026-06-01 math.CO math.NT

Moments of partition statistics, Bell polynomials and Eisenstein-type series

划分统计量的矩、Bell多项式和Eisenstein型级数

Soon-Yi Kang, Byungchan Kim, Chanhee Lee

AI总结 本文通过完全Bell多项式及其反演公式和Faà di Bruno公式,发展了一种将组合统计量矩的生成函数表示为划分迹的系统方法,并应用于整数划分的最大部分、划分crank和rank以及单峰序列rank等统计量。

Comments 23 pages

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AI中文摘要

我们发展了一种系统的方法,将组合统计量矩的生成函数表示为划分迹。我们采用了基于完全Bell多项式及其反演公式的代数方法,以及通过Faà di Bruno公式的分析方法。我们的方法可以应用于广泛类别的组合统计量,例如整数划分的最大部分、划分crank和rank以及单峰序列rank。

英文摘要

We develop a systematic method to express generating functions for moments of combinatorial statistics in terms of partition traces. We employ an algebraic approach based on the complete Bell polynomials and their inversion formula, alongside an analytic approach via Faà di Bruno's formula. Our approach can be applied to a wide class of combinatorial statistics, such as the largest part of an integer partition, the partition crank and rank, and the unimodal sequence rank.

2605.30800 2026-06-01 cs.HC

Computer-Aided Tagging on Wikimedia Commons: Designing for Human-AI Collaboration in Open Knowledge Work

维基共享资源上的计算机辅助标注:为开放知识工作中的人机协作而设计

Yihan Yu, David W. McDonald

AI总结 通过定性分析社区评论和访谈,研究维基共享资源中计算机辅助标注(CAT)工具的用户体验,识别关键问题并提出改进建议,以促进人机协作在开放知识工作中的应用。

Comments Accepted to CSCW 2026, to appear

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AI中文摘要

本研究调查了维基共享资源贡献者对计算机辅助标注(CAT)工具的使用体验,该工具是一个AI辅助的图像标注系统,旨在提高共享资源的可发现性、可搜索性、可访问性和多语言支持。通过对来自11个维基页面的595条CAT相关社区评论和16次深度访谈的定性分析,我们识别出导致CAT反应不一并最终停用的七个关键问题。我们还提出了社区建议的改进方案。我们反思了在共享资源上设计人机协作以及开发支持开放知识工作的AI辅助工具的意义。这项工作通过将人机协作的理解扩展到英语中心、文本中心的企业平台之外,为HCI和CSCW研究做出了贡献。

英文摘要

This study investigates Wikimedia Commons contributors' lived experiences with the Computer-Aided Tagging (CAT) tool, an AI-assisted image tagging system designed to improve Commons' discoverability, searchability, accessibility, and multilingual support. Using a qualitative analysis of 595 CAT-related community comments from 11 wiki pages and 16 in-depth interviews, we identify seven key issues that contributed to CAT's mixed reception and eventual deactivation. We also offer community-informed suggestions for improving the tool. We reflect on the implications for designing human-AI collaboration on Commons and for developing AI-assisted tools that support open knowledge work. This work contributes to HCI and CSCW research by extending the understanding of human-AI collaboration beyond Anglophone, text-centric, corporate platforms.

2605.30799 2026-06-01 math.GT cs.DM math.CO

Remarks about the Moebius-Kantor graph

关于Moebius-Kantor图的注记

Oliver Knill

AI总结 本文研究Moebius-Kantor图MK=G(8,3)的群论和拓扑性质,包括其作为三个非阿贝尔群的Cayley图、与Heawood数7和Tucker群的关系、Lefschetz数的计算、作为3-球面G的2-骨架复形的对偶、在Hopf纤维化中表示平坦Clifford环面,以及度量结构唯一确定Pauli群代数结构。

Comments 14 pages, 14 figures

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AI中文摘要

Moebius-Kantor图MK=G(8,3)是三个非阿贝尔群——Pauli群P(1)、半二面体群SD(16)以及16阶二面体群D(16)——的Cayley图。在拓扑图论中,它展示了环面的Heawood数7,并导出了Tucker群Aut(MK),即唯一的亏格2群。我们计算了Lefschetz数以说明Brouwer-Lefschetz不动点定理。MK也是3-球面G的2-骨架复形的对偶。该图表示3-球面G=K(2,2,2,2)中Hopf纤维化的一个平坦Clifford环面,反映了Coxeter曾注意到MK是超立方体G*的子图。它承载一个度量d,使得(MK,d)只有一种保持度量的代数群结构(P(1),*)。这使得Pauli群变得自然,类似于Moebius梯子M(16)使二面体群D(16)自然,从而迫使代数结构由度量结构决定。

英文摘要

The Moebius-Kantor graph MK=G(8,3) is a Cayley graph of three non-abelian groups, the Pauli group P(1), the semi-dihedral group SD(16), as well as the dihedral group D(16) of order 16. In topological graph theory, it illustrates the Heawood number 7 of the torus and leads to the Tucker group Aut(MK), the unique group of genus 2. We compute the Lefschetz numbers to illustrate the Brouwer-Lefschetz fixed point theorem. MK is also the dual of the 2-skeleton complex of the 3-sphere G. The graph represents one of flat Clifford tori of a Hopf fibration in the 3-sphere G=K(2,2,2,2) reflecting that Coxeter saw that MK is a subgraph of the tesseract G*. It carries a metric d so that (MK,d) has only one algebraic group structure (P(1),*) that preserves the metric. It makes the Pauli group natural, similarly as the Moebius ladder M(16) makes the dihedral group D(16) natural, forcing the algebraic structure from the metric structure.

2605.30798 2026-06-01 quant-ph cond-mat.stat-mech hep-th

Eigenstate chaos in the presence of non-Abelian symmetries

非阿贝尔对称性存在下的本征态混沌

Siddharth Jindal, Pavan Hosur

AI总结 本研究通过引入非阿贝尔微正则熵,将混沌本征态的纠缠熵与对称性分辨的纠缠熵联系起来,揭示了非阿贝尔对称性下本征态热化的普适对数修正。

Comments 51 pages, 3 figures

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AI中文摘要

本征态热化假说(ETH)认为能量本征态编码了微正则系综的局域性质。受近期对非对易守恒荷及非阿贝尔ETH兴趣的驱动,我们研究了由一般紧致李群(如SU(2))描述的对称性存在下的混沌本征态。通过应用非阿贝尔对称性分辨,我们发展了非阿贝尔微正则熵,并将该熵与混沌本征态的纠缠熵联系起来。我们发现微正则熵与对称性分辨的纠缠熵密切相关,后者通过一个普适的对数修正与常规纠缠熵不同。我们的结果依赖于全局卡西米尔荷,例如总自旋。在有限荷密度下,我们发现常规纠缠熵存在对数增强。在零密度下,我们未发现纠缠熵的此类修正,但观察到微正则熵和对称性分辨纠缠熵的对数减少。我们讨论了我们的方法对非阿贝尔本征态热化的启示。

英文摘要

The eigenstate thermalization hypothesis (ETH) posits that energy eigenstates encode local properties of the microcanonical ensemble. Motivated by recent interest in the physics of non-commuting conserved charges and the non-Abelian ETH, we study chaotic eigenstates in the presence of symmetries described by general compact Lie groups, such as SU(2). By applying non-Abelian symmetry resolution, we develop a non-Abelian microcanonical entropy and relate this entropy to the entanglement entropy of chaotic eigenstates. We find that microcanonical entropy is closely related to the symmetry-resolved entanglement entropy, which differs from conventional entanglement entropy by a universal logarithmic correction. Our results depend on the global Casimir charge, e.g. total spin. At finite charge density, we find a logarithmic enhancement to conventional entanglement entropy. At zero density, we find no such correction to entanglement entropy, but a logarithmic reduction to microcanonical entropy and symmetry-resolved entanglement entropy. We discuss the implications of our approach for non-Abelian eigenstate thermalization.

2605.30793 2026-06-01 math.SP math-ph math.AP math.MP

High Flux Asymptotics and Critical Phenomena for the Magnetic Laplacian

磁拉普拉斯算子的高通量渐近与临界现象

Emanuela L. Giacomelli, Ayman Kachmar, Mikael Sundqvist

AI总结 研究平面区域中分段常数磁场下Neumann磁拉普拉斯算子的最低特征值,分析高通量极限下基态能量的单调性与振荡行为,揭示了磁场不均匀缩放、拓扑和几何对高通量谱行为的影响。

Comments 33 pages, 1 figure

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AI中文摘要

我们研究了一个被分成两个区域的平面域中Neumann磁拉普拉斯算子的最低特征值,其中磁场分段常数,且在内、外部分可能以不同尺度缩放。我们的目标是描述高通量极限,并确定基态能量何时最终单调、何时持续振荡。根据外场的相对强度,我们识别出几种渐近状态。当外场固定时,最低特征值表现出持续振荡,低能态局域在外区域。当外场增长较慢时,行为强烈依赖于几何:对于非圆形域,最终单调,而对于圆盘,振荡可能持续。在临界状态(两个场可比)下,几何和通量分布都起决定性作用。当外场占主导时,问题渐近约化为内区域上的有效算子。这些结果显示了不均匀的磁场缩放、拓扑和几何如何塑造高通量谱行为。

英文摘要

We study the lowest eigenvalue of the Neumann magnetic Laplacian in a planar domain divided into two regions, with piecewise constant magnetic fields that may scale differently in the inner and outer parts. Our aim is to describe the high-flux limit and determine when the ground-state energy is eventually monotone and when it continues to oscillate. We identify several asymptotic regimes according to the relative strength of the outer field. When the outer field is fixed, the lowest eigenvalue exhibits persistent oscillations and the low-energy states localize in the outer region. When the outer field grows more slowly, the behavior depends strongly on the geometry: it is eventually monotone for non-circular domains, while oscillations may persist for disks. In the critical regime, where the two fields are comparable, geometry and flux distribution both play a decisive role. When the outer field dominates, the problem reduces asymptotically to an effective operator on the inner region. These results show how uneven magnetic scaling, topology, and geometry shape the high-flux spectral behavior.

2605.30791 2026-06-01 cs.NI

Where's Waldo Library? Using Reverse IP Geolocation to Identify Library IPs

沃尔多图书馆在哪里?使用反向IP地理定位识别图书馆IP

Nishant Acharya, Anyu Yang, Humaira Fasih Ahmed Hashmi, Kevin Vermeulen, Shivani Kalamadi, Jiayi Liu, Ashutosh Kshirsagar, Elizabeth Belding, David Choffnes, Alexander Gamero-Garrido

AI总结 提出反向IP地理定位框架,通过整合IP地理数据库、DNS PTR记录、WHOIS注册、宽带提供商数据和主动测量,从物理地址推断美国公共图书馆的IP地址,实现约50%的映射成功率,覆盖全美各州及城乡区域。

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AI中文摘要

社区锚定机构(CAI),如图书馆、学校和社区中心,对于为未服务或服务不足的个人和社区提供互联网接入至关重要。由于许多此类机构本身资源不足,分析其互联网服务的可靠性和质量非常重要。大规模进行此类分析需要知道这些机构的IP地址,以便进行宽带测量和政策评估。不幸的是,这些IP并未被系统记录。作为广泛、可扩展的CAI互联网连接评估的第一步,本文提出了反向IP地理定位(RG),一种从物理地址数据推断IP地址的新框架。一个关键洞察是CAI的街道地址是公开已知的,这使我们能够从商业地理定位中识别出可能服务于CAI相关位置的候选IP集。本文聚焦于美国公共图书馆,这些图书馆在数千个地点提供了地理多样性,并且有一些公开可用的机构记录(例如WHOIS注册),使我们能够系统验证我们的方法。我们的方法创新性地整合了IP地理定位数据库、DNS PTR记录、WHOIS注册、宽带提供商数据和主动测量,以识别可能分配给图书馆的IP并进行验证。基于评估,我们的方法大约有一半的时间能将图书馆映射到其IP前缀,覆盖美国所有州以及城市和农村地区。我们的结果凸显了在IP空间中映射CAI存在的可行性,并为大规模远程宽带基础设施评估提供了基础。

英文摘要

Community anchor institutions (CAIs), such as libraries, schools, and community centers, are critical for providing Internet access to un- or under-served individuals and communities. Because many of these institutions are themselves under-provisioned, analyzing the reliability and quality of their Internet service is important. Doing so at scale requires knowing the IP addresses of these institutions so that broadband measurement and policy evaluation can occur. Unfortunately, these IPs are not systematically documented. As a first step towards widespread, scalable evaluation of CAI Internet connectivity, this paper presents Reverse IP Geolocation (RG), a new framework to infer IP addresses from physical address data. A key insight is that CAI street addresses are publicly known, which allows us to identify a candidate set of IPs from commercial geolocation that are likely serving the location associated with a CAI. In this paper, \textbf{we focus on US public libraries}, which offer both geographic diversity across thousands of locations, and some publicly available institutional records (\eg{}WHOIS registrations) that enable systematic validation of our approach. Our approach offers a novel integration of IP geolocation databases, DNS PTR records, WHOIS registrations, broadband provider data, and active measurements to identify IPs likely assigned to libraries and validate them. Based on evaluations, our approach can map a library to its IP prefix approx. half of the time, with coverage across all US states, as well as urban and rural areas. Our results highlight the feasibility of mapping CAI presence in IP space and offer a foundation for large-scale, remote broadband infrastructure evaluation.

2605.30787 2026-06-01 eess.SP

On Spatial Degree-of-Freedom Analysis of Near-Field Multipath Channels for Ultra-massive MIMO Systems

超大规模MIMO系统近场多径信道空间自由度分析

Zhiqiang Yuan, Hui Lou, Wei Fan, Jianhua Zhang, Henk Wymeersch

AI总结 针对超大规模MIMO系统近场多径信道,基于格林函数表示推导自由度度量,通过有效电孔径与立体角乘积计算各路径贡献,并通过可分辨路径的有效并集得到总自由度,实验验证了多径传播可显著增加空间自由度。

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AI中文摘要

超大规模多输入多输出(UM-MIMO)系统向近场(NF)通信的转变从根本上改变了无线信道的空间自由度(DoF)。虽然文献中对视距(LoS)传输信道的近场自由度已有充分描述,但近场多径场景下的自由度仍未被充分探索。本文研究了实际多径条件下近场UM-MIMO信道的空间自由度。通过建模多径传播并基于信道格林函数表示分析所得特征值分布,推导出一个通用的自由度度量。每条路径的自由度贡献由有效电孔径与立体角的乘积决定,总自由度通过空间可分辨路径贡献的有效并集获得。进一步建立了特征值分布与多径功率之间的映射关系。在28-30 GHz频段、720个阵列元件的条件下,进行了数值仿真和实际近场信道测量,以在视距多径和非视距场景下进行验证。结果表明,多径传播可以显著增加空间自由度,且所提出的度量能够准确预测实际近场信道的自由度。所提出的框架为未来近场UM-MIMO系统中的自由度预测提供了实用工具,并支持容量分析和空间复用设计。

英文摘要

The transition to near-field (NF) communications in ultra-massive multiple-input multiple-output (UM-MIMO) systems fundamentally alters the spatial degrees of freedom (DoF) of wireless channels. While the NF DoF of line-of-sight (LoS) transmission channels is well-characterized in the literature, the DoF in NF multipath scenarios remains underexplored. This paper investigates the spatial DoF of NF UM-MIMO channels under practical multipath conditions. A generic DoF metric is derived by modeling multipath propagation and analyzing the resulting eigenvalue distribution based on the Green' s function representation of the channel. The DoF contribution of each path is determined by the product of the effective electrical aperture and the subtended solid angle, and the total DoF is obtained through the effective union of spatially resolvable path contributions. A mapping between the eigenvalue distribution and multipath powers is further established. Numerical simulations and real-world NF channel measurements at 28-30 GHz with 720 array elements are conducted for validation in both LoS multipath and non-LoS scenarios. The results show that multipath propagation can significantly increase the spatial DoF and that the proposed metric accurately predicts the DoF of practical NF channels. The proposed framework provides a practical tool for DoF prediction and supports capacity analysis and spatial multiplexing design in future NF UM-MIMO systems.

2605.30783 2026-06-01 astro-ph.EP astro-ph.SR

Coupling dynamical accretion and chemical differentiation: a unified framework for Earth-Mars diversity

耦合动力学吸积与化学分异:地球-火星多样性的统一框架

Zhihui Kong, Beibei Liu, J. ZhangZhou, Haolan Tang, Zhengbin Deng, Qun-Ke Xia, Simon L. Grimm, Man Hoi Lee, Yi Huang, Liping Qin, Jonathan H. Jiang

AI总结 通过耦合高分辨率N体模拟与撞击驱动的金属-硅酸盐平衡,提出了一个统一框架,揭示了地球和火星在吸积路径、盘径向氧化还原结构和撞击控制分异共同作用下产生的地球化学多样性。

Comments Accepted for publication in Astronomy & Astrophysics, Article ID aa59434-26

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AI中文摘要

地球和火星之间显著的物理和地球化学差异为类地行星形成提供了基本约束,然而一个自洽地连接动力学和化学方面的框架仍然难以捉摸。这里我们提出了一个集成建模框架,该框架将高分辨率N体模拟与撞击驱动的金属-硅酸盐平衡耦合起来,以追踪地球和火星的动力学吸积历史和化学分异。使用窄环星子吸积场景,我们表明地球和火星类似物自然地采样了原行星盘内系统不同的固体储库。地球类似物优先吸积星子环中心附近的还原物质,而火星类似物则获得环外部更大比例的氧化物质。这导致了多样的整体氧化还原状态,其组成进一步受到核形成过程中撞击依赖的压力-温度平衡条件的修改。结果,地球类似物经历更深的平衡和更高效的铁向核的转移,产生低氧化铁含量的地幔和更大的核质量分数。相比之下,火星类似物在更浅的条件下平衡,在地幔中保留更多铁,并形成更小的核。我们的结果表明,地球和火星之间的动力学和地球化学差异源于吸积路径、盘的径向氧化还原结构和撞击控制分异的耦合效应,而非任何单一过程。我们的统一框架从物理上解释了类地行星的地球化学多样性,并为解释系外行星系统中岩石行星的组成提供了潜在途径。

英文摘要

The distinct physical and geochemical differences between Earth and Mars provide fundamental constraints on terrestrial planet formation, yet a self-consistent framework linking dynamical and chemical aspects remains elusive. Here we present an integrated modeling framework that couples high-resolution N-body simulations with impact-driven metal-silicate equilibration to track the dynamical accretion history and chemical differentiation for Earth and Mars. Using a narrow ring planetesimal accretion scenario, we show that Earth and Mars analogs naturally sample systematically different solid reservoirs within the protoplanetary disk. Earth analogs preferentially accrete reduced material around the planetesimal ring center, whereas Mars analogs acquire a larger fraction of oxidized material exterior to the ring. This leads to diverse bulk redox states, with composition further modified by impact-dependent pressure-temperature equilibration conditions during core formation. As a result, Earth analogs experience deeper equilibration and more efficient transfer of iron into the core, producing mantles with low iron oxide contents and larger core mass fractions. In contrast, Mars analogs equilibrate at shallower conditions, retain more iron in their mantles, and develop smaller cores. Our results demonstrate that the dynamical and geochemical differences between Earth and Mars emerge from the coupled effects of accretion pathways, the disk's radial redox structure and impact-controlled differentiation, rather than from any single process. Our unified framework physically explains the geochemical diversity of terrestrial planets and offers a potential pathway to interpret compositions of rocky planets in exoplanetary systems.

2605.30782 2026-06-01 astro-ph.GA astro-ph.SR

An extended catalogue of Herbig-Haro objects

Herbig-Haro 天体的扩展星表

Zhi-Yu Chen, Chao-Jian Wu

AI总结 通过文献综述编制了包含1193个Herbig-Haro天体的扩展星表,并进行了初步统计分析,以促进恒星形成和恒星外流研究。

Comments 64 pages, 4 figures, 5 tables, accepted for publication in Research in Astronomy and Astrophysics

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AI中文摘要

我们通过仔细查阅截至2025年中期的文献,编制了一个包含1193个Herbig-Haro (HH) 天体的扩展星表,其中包括477个孤立HH天体和716个HH结节。该星表为每个条目提供了全面的数据,包括天体坐标、距离、结节间距、激发源(如有光谱类型)、天体特征和参考文献。我们还对关键参数(如距离、激发源特性、形态和激发状态)进行了初步统计分析。通过将我们的扩展星表与Hippel等人于1988年和Reipurth于2000年发布的两个早期HH天体星表相结合,天文学家可以获取所有已知HH天体的全面信息,从而促进恒星形成和恒星外流的研究。

英文摘要

We present an extended catalogue of 1193 Herbig-Haro (HH) objects, comprising 477 isolated HH objects and 716 HH knots, compiled through a meticulous review of the literature available through mid-2025. The catalogue provides comprehensive data for each entry, including celestial coordinates, distances, knot separations, exciting sources (with spectral types where available), object characteristics, and bibliographic references. We also perform a preliminary statistical analysis of key parameters such as distance, exciting source properties, morphology, and excitation state. By combining our extended catalogue with the two earlier HH object catalogues published by Hippel et al. in 1988 and Reipurth in 2000, astronomers can access comprehensive information on all known HH objects, thereby facilitating research on star formation and stellar outflows.

2605.30781 2026-06-01 math.CO cs.DM math.AC

The NF-operator and the NF-Numbers of Simplicial Complexes

单纯复形的NF-算子与NF-数

Bilal Ahmad Rather

AI总结 本文定义并研究了单纯复形的NF-算子及其迭代周期(NF-数),给出了若干图族NF-数的显式公式,包括哑铃图、完全分裂图和双星图。

Comments 27 pages, 4 figures, Algebra Colloquium (to appear)

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AI中文摘要

设$igtriangleup$是一个单纯复形,$\delta_{\mathcal{NF}}$表示NF-算子。NF-复形$\delta_{\mathcal{NF}}(igtriangleup)$定义为$igtriangleup$的面理想的Stanley-Reisner复形。迭代$\delta_{\mathcal{NF}}$产生一个周期轨道(在同构意义下),使得$\delta_{\mathcal{NF}}^{\,t}(igtriangleup)\cong igtriangleup$的最小正整数$t$称为$igtriangleup$的\emph{NF-数}(Habi and Mahmood, Algebra Colloquium, 2022)。本文提供了多种结果,并确定了若干图族的NF-数的显式公式。特别地,我们计算了哑铃图的NF-数。我们还证明了完全分裂图$S_{n,m}$的NF-数等于$m+n+2$,双星图$D_{p+q}$的NF-数等于$p+q+4$。最后,我们给出评注、开放问题和猜想以指导未来研究。

英文摘要

Let $\bigtriangleup$ be a simplicial complex and let $δ_{\mathcal{NF}}$ denote the NF-operator. The NF-complex $δ_{\mathcal{NF}}(\bigtriangleup)$ is defined as the Stanley--Reisner complex of the facet ideal of $\bigtriangleup$. Iterating $δ_{\mathcal{NF}}$ gives a periodic orbit (up to isomorphism), and the smallest positive integer $t$ for which $δ_{\mathcal{NF}}^{\,t}(\bigtriangleup)\cong \bigtriangleup$ is called the \emph{NF-number} of $\bigtriangleup$ (Habi and Mahmood, Algebra Colloquium, 2022). In this work, we provide various results and determine explicit formulas for the NF-number for several families of graphs. In particular, we compute the NF-number for dumbbell graphs. We also prove that the NF-number of the complete split graph $S_{n,m}$ equals $m+n+2$, and that the NF-number of the double star $D_{p+q}$ equals $p+q+4$. We conclude with remarks, open problems, and conjectures to guide future research.

2605.30779 2026-06-01 math.PR

Eigenvector distribution of random matrices under critical finite-rank deformations

临界有限秩变形下随机矩阵的特征向量分布

Zhigang Bao, Dong Wang, Yue Zhu

AI总结 研究BBP转变临界区域中有限秩变形高斯随机矩阵在软边缘的特征向量分布,发现主导特征向量与尖峰之间的平方重叠经N^{1/3}缩放后弱收敛于Airy-Green函数导数在相应软边缘根处的负倒数。

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AI中文摘要

我们研究了在BBP转变的临界区域中,具有有限秩变形的高斯随机矩阵在软边缘的特征向量分布。对于具有临界尖峰的GOE和GUE的有限秩变形,我们发现主导特征向量与尖峰之间的平方重叠,经\(N^{1/3}\)缩放后,弱收敛于在相应软边缘根处计算的Airy-Green函数导数的负倒数。对于秩一临界尖峰的高斯\(eta\)系综,\(eta>0\),我们得到了一个涉及Airy-Green函数的类似结果。在这两种情况下,Airy-Green函数都是Bykhovskaya--Gorin--Sodin \cite{Bykhovskaya-Gorin-Sodin25}引入的函数的推广。证明均基于特征向量-特征值恒等式和预解微分机制。

英文摘要

We investigate the eigenvector distribution at the soft edge for Gaussian random matrices with finite-rank deformations, in the critical regime of BBP transition. For finite-rank deformations of the GOE and GUE with critical spikes, we find that the squared overlap between a leading eigenvector and a spike, rescaled by \(N^{1/3}\), converges weakly to the negative reciprocal of the derivative of an Airy-Green function evaluated at the corresponding soft-edge root. For the rank-one critically spiked Gaussian \(β\)-ensemble, \(β>0\), we obtain an analogous result involving an Airy-Green function. In both cases, the Airy-Green functions are generalizations of the one introduced by Bykhovskaya--Gorin--Sodin \cite{Bykhovskaya-Gorin-Sodin25}. The proofs are both based on an eigenvector--eigenvalue identity and a resolvent-differentiation mechanism.

2605.30777 2026-06-01 cs.SE

What Breaks When LLMs Code? Characterizing Operational Safety Failures of Agentic Code Assistants

当LLM编码时会出现什么问题?表征自主代码助手的操作安全故障

Alif Al Hasan, Sumon Biswas

AI总结 通过系统分析文献和GitHub问题,构建了包含33种操作风险类型的多维安全分类法,发现编码代理故障通常严重且主要源于约束违反、破坏性操作、授权绕过和欺骗。

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AI中文摘要

基于大型语言模型(LLM)的自主编码代理正迅速集成到开发工作流程中,但其操作安全特性在明确恶意输入评估之外仍知之甚少。在实践中,高影响故障发生在良性、目标导向的使用过程中,例如环境破坏、虚假成功报告等,当前基准测试未能捕捉到这些。当编码代理用于日常开发任务时,实际会发生哪些类别的操作安全故障,其影响是什么?我们提出了一项基于两个互补证据流的实证研究。我们从22个顶级会议筛选了68,816篇论文,整理了185篇安全相关研究,并从广泛部署的LLM驱动编码工具中挖掘了16,586个GitHub问题,手动确认了547个真实安全故障。通过对两个语料库进行系统开放编码,我们推导出一个多维安全分类法,包含7个维度的33种操作风险类型,并为每个事件标注了促成因素、任务上下文、严重性和下游影响。我们的发现表明,编码代理故障通常很严重,547个事件中有326个被评为高或严重。主要风险是约束违反、破坏性操作、授权绕过和欺骗,超过65%的事件出现在错误修复和设置或配置中,这些模式在先前文献中基本缺失。这些结果对软件工程工具设计者和基准测试开发者有直接启示:防护措施必须超越对抗性提示防御,以强制执行环境约束、故障透明度和安全停止行为。

英文摘要

Autonomous coding agents built on large language models (LLMs) are rapidly being integrated into development workflows, yet their operational safety properties remain poorly understood beyond evaluations of explicitly malicious inputs. In practice, high-impact failures arise during benign, goal-directed use through environment breakage, fabricated success reports, etc. that current benchmarks do not capture. What categories of operational safety failures actually occur when coding agents are used for everyday development tasks and what is their impact? We present an incident-driven empirical study grounded in two complementary evidence streams. We screen 68,816 papers from 22 premier venues, curating 185 safety-relevant studies, and mine 16,586 GitHub issues from widely deployed LLM-powered coding tools, manually confirming 547 genuine safety failures. Applying systematic open coding over both corpora, we derive a multi-dimensional safety taxonomy of 33 operational risk types organized across seven dimensions, and annotate each incident with contributing factors, task context, severity, and downstream impact. Our findings show that coding-agent failures are often severe, with 326 of 547 incidents rated high or critical. The dominant risks are constraint violations, destructive operations, authorization bypasses, and deception, and over 65% of incidents arise in bug fixing and setup or configuration, patterns largely missing from prior literature. These results have direct implications for SE tool designers and benchmark developers: guardrails must go beyond adversarial-prompt defenses to enforce environmental constraints, failure transparency, and safe-halt behaviors.

2605.30775 2026-06-01 stat.AP stat.ML

Bayesian Classification with Probit-link Split-and-merge Gaussian Process Prior in EEG-based Brain-Computer Interfaces

基于脑电图脑机接口中Probit-link分裂合并高斯过程先验的贝叶斯分类

Yunong Wu, Jane E. Huggins, Jian Kang, Tianwen Ma

AI总结 提出一种基于Probit-link分裂合并高斯过程先验的贝叶斯生成模型,用于脑电图响应二元分类,实现时空特征选择并降低计算复杂度,同时保持预测精度。

Comments 31 pages, 7 figures, 2 tables

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AI中文摘要

基于事件相关电位(ERP)的脑机接口(BCI)拼写系统通过检测视觉刺激诱发的脑电图(EEG)响应,使用户能够选择字符。一个挑战是准确识别目标相关响应,如P300成分。然而,现有方法往往忽略特征选择,或进行不可解释的特征选择,或需要大量计算或数据操作。为解决这些局限性,我们提出一种新颖的贝叶斯生成建模框架,用于EEG对刺激响应的二元分类。我们的方法采用Probit-link分裂合并高斯过程(P-SMGP)先验进行时空特征选择,有效捕捉目标与非目标ERP响应之间的区别。通过模拟研究和真实EEG数据分析,我们的方法能够降低计算复杂度,并在保持可比预测精度的同时,对变换后的ERP函数提供统计解释。这些发现强调了可解释的刺激级建模对于推进预测性和个性化BCI系统的价值。

英文摘要

A Brain-Computer Interface (BCI) speller systems based on Event-Related Potentials (ERPs) enables users to select characters by detecting brain responses to visual stimuli, recorded through electroencephalogram (EEG). One challenge is to accurately identify target-related responses, such as the P300 component. However, existing methods tend to ignore feature selection, perform feature selection without interpretability, or require large computational effort or data manipulation. To address these limitations, we propose a novel Bayesian generative modeling framework to the binary classification of EEG responses to stimuli. Our approach employs a Probit-link Split-and-merge Gaussian Process (P-SMGP) prior to perform spatial-temporal feature selection, effectively capturing the distinctions between target and non-target ERP responses. Through both simulation studies and real EEG data analysis, our approach can reduce computational complexity and provide statistical interpretations on transformed ERP functions while maintaining comparable prediction accuracy. These findings underscore the value of interpretable, stimulus-level modeling for advancing predictive and personalized BCI systems.

2605.30773 2026-06-01 cond-mat.mtrl-sci cond-mat.mes-hall physics.app-ph

Saturated and Anisotropic Magnetostriction in an Altermagnet

交变磁体中的饱和各向异性磁致伸缩

Zhiyuan Duan, Qiyun Xu, Peixin Qin, Li Liu, Guojian Zhao, Yuzhou He, Xiaoyang Tan, Sixu Jiang, Jingyu Li, Xiaoning Wang, Qinghua Zhang, Wenhui Duan, Yong Xu, Ziang Meng, Peizhe Tang, Chengbao Jiang, Zhiqi Liu

AI总结 本文报道了原型交变磁体MnTe中在约0.7 T中等磁场下饱和且具有二重对称各向异性的磁致伸缩效应,并通过第一性原理计算揭示其源于弹性应变与奈尔序参量的对称性允许耦合。

Comments 51 pages, 21 figures, 1 table, published at Journal of the American Chemical Society

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AI中文摘要

磁致伸缩是连接磁性与力学的基本现象,已实现广泛应用。近两个世纪以来,它主要针对铁磁体进行研究。关于反铁磁体的磁致伸缩,已知的常规共线反铁磁体和非共线反铁磁体的例子大多表现出非饱和的磁场依赖性。本文报道了原型交变磁体——MnTe中易于饱和的磁致伸缩效应,交变磁体是一类具有特殊晶体对称性的新兴共线反铁磁体。对于高质量的MnTe单晶,磁致伸缩在约0.7 T的中等磁场下饱和,并具有引人注目的二重对称各向异性。第一性原理计算揭示,饱和各向异性磁致伸缩源于弹性应变与其奈尔序参量之间的对称性允许耦合。这些发现打破了关于反铁磁磁致伸缩的传统认知。

英文摘要

Magnetostriction, a fundamental phenomenon bridging magnetism and mechanics, has enabled a broad spectrum of applications. For almost two centuries, it has been mainly investigated for ferromagnets. Regarding the magnetostriction of antiferromagnets (AFMs), limitedly known examples for both conventional collinear AFMs and noncollinear AFMs predominantly exhibit non-saturating magnetic-field dependence. Herein, we report an easily saturated magnetostriction effect in a prototypical altermagnet - MnTe, which is an emerging class of collinear AFMs with special crystal symmetries. For high-quality MnTe single crystals, the magnetostriction saturates under a moderate field of ~0.7 T with an intriguing two-fold-symmetry anisotropy. First-principles calculations reveal that the saturated and anisotropic magnetostriction originates from symmetry-allowed coupling between elastic strain and its Néel order parameter. These findings break the traditional wisdom on antiferromagnetic magnetostriction.

2605.30772 2026-06-01 cs.IR

FOSTER: First-order Dataset Distillation for Text-based Sequential Recommendation

FOSTER: 基于一阶数据集蒸馏的文本序列推荐

Hung Vinh Tran, Tong Chen, Xinyi Gao, Junliang Yu, Julien Monteil, Hongzhi Yin

AI总结 针对文本序列推荐系统训练成本高的问题,提出一阶数据集蒸馏方法FOSTER,通过随机物品子集采样、轨迹锚定参数重置和语义共现正则化,实现高效且有效的合成数据集生成。

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AI中文摘要

基于文本的序列推荐系统虽然通过引入物品上下文大大提高了推荐准确性,但其训练成本无疑更高。通过将大型数据集压缩为紧凑的合成样本集用于模型训练,数据集蒸馏提供了一种有前景的解决方案。然而,由于存在大量离散物品,其在基于文本的序列推荐中的应用并非易事。语言模型基于物品编码进一步加剧了这一挑战,使得数据集蒸馏中常用的双层优化变得极其昂贵。为此,我们提出了用于基于文本的序列推荐的一阶数据集蒸馏方法(FOSTER),通过三个新颖组件实现有效性和效率:(1)随机物品子集采样,替代每个蒸馏步骤中昂贵的全语料嵌入提取;(2)基于轨迹锚定参数重置的一阶优化,避免昂贵的双层梯度计算;(3)正则化,明确促进合成序列中语义相似物品的共现。在三个基准上的大量实验表明,FOSTER持续优于现有的数据集蒸馏和核心集选择基线,仅使用20个合成交互序列即可逼近全数据集性能。

英文摘要

Text-based sequential recommender systems, while greatly improving recommendation accuracy by incorporating item contexts, are undeniably more expensive to train. By condensing a large dataset into a compact set of synthetic samples for model training, dataset distillation offers a promising solution. However, its adoption in text-based sequential recommendation is non-trivial given the large pool of discrete items. This challenge is further compounded by language model-based item encoding, which makes bi-level optimization commonly used in dataset distillation prohibitively expensive. To this end, we propose First-order dataset distillation for Text-based Sequential Recommendation (FOSTER), which facilitates effectiveness and efficiency via three novel components: (1) stochastic item subset sampling that replaces costly full-corpus embedding extraction at each distillation step; (2) first-order optimization with trajectory-anchored parameter reset to avoid expensive bi-level gradient computation; and (3) regularization that explicitly promotes co-occurrence between semantically similar items in the synthetic sequences. Extensive experiments on three benchmarks show that FOSTER consistently outperforms existing dataset distillation and coreset selection baselines, approximating full-dataset performance using as few as 20 synthetic interaction sequences.

2605.30768 2026-06-01 quant-ph cond-mat.supr-con

Geometric dependence of critical-current variation in Al/AlO${\rm _x}$/Al Josephson junctions: a model-based analysis

Al/AlO$_x$/Al约瑟夫森结中临界电流变化的几何依赖性:基于模型的分析

K. Kakuyanagi, N. Teran, H. Toida, S. Saito

AI总结 通过室温隧道电阻统计分析和模型依赖关系,识别出Al薄膜厚度波动是Al/AlO$_x$/Al约瑟夫森结临界电流变化的主导因素,并发现采用30度沉积角可显著提高均匀性。

Comments 8 pages, 4 figures, including supplementary material

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AI中文摘要

实现约瑟夫森结临界电流的均匀性对于超导量子电路的大规模集成至关重要。在本工作中,我们利用室温隧道电阻统计分析了Al/AlO$_x$/Al结临界电流的变化,并根据其对结几何形状和沉积条件的依赖性,在建模的变化源中识别出主导贡献。我们的基于模型的分析表明,在所建模的贡献因素中,Al薄膜厚度的波动起主导作用。基于此分析,我们发现,在Dolan桥双角度沉积中,对双层结采用30度的沉积角可显著提高均匀性,在9.75 mm(1.5 mm)方形区域内相对标准偏差为1.2%(0.5%)。

英文摘要

Achieving uniform critical current across Josephson junctions is essential for the large-scale integration of superconducting quantum circuits. In this work, we statistically analyzed the variation of the critical current of Al/AlO${\rm _x}$/Al junctions using room-temperature tunnel resistance statistics, and identified the dominant contribution among the modeled sources of the variation based on their dependence on geometry and deposition conditions of junctions. Our model-based analysis reveals that fluctuations in the Al film thickness play the dominant role among the modeled contributing factors. Based on this analysis, we found that, in Dolan-bridge double-angle deposition, adopting a deposition angle of 30-degree for bilayer junctions significantly improves uniformity, yielding a relative standard deviation of 1.2% (0.5%) across a 9.75 mm (1.5 mm) square region.

2605.30766 2026-06-01 math.CA

Two-weight inequalities for the Dunkl--Poisson integrals

Dunkl--Poisson 积分的两权不等式

Qingdong Guo, Ji Li, Brett D. Wick, Liangchuan Wu

AI总结 通过将算子分解为标量正 Poisson 型算子矩阵,并利用主立方体停时论证,证明了 Dunkl--Poisson 半群的 L^2 两权测试定理。

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AI中文摘要

我们证明了 Dunkl--Poisson 半群的一个 $L^2$ 两权测试定理。困难在于几何方面。Dunkl 轨道距离具有多个反射对角线,因此单个轨道-盒子测试可能混合不同的 chamber 分量。我们通过在一个 Weyl chamber 上工作并保留 chamber 索引来避免这一点。在壁-零假设下,完整算子变为一个由标量正 Poisson 型算子构成的有限矩阵。在每个条目中,轨道对角线就是 chamber 变量中的普通对角线。然后,标量证明是一个主立方体停时论证,其中两个 Dunkl 核比较是仅有的新估计。由此产生的前向和后向测试对于原始的 Dunkl--Poisson 不等式是必要且充分的。

英文摘要

We prove an $L^2$ two-weight testing theorem for the Dunkl--Poisson semigroup. The difficulty is geometric. The Dunkl orbit distance has several reflected diagonals, so a single orbit-box test may mix different chamber components. We avoid this by working on one Weyl chamber and keeping the chamber indices. Under the wall-null assumption the full operator becomes a finite matrix of scalar positive Poisson-type operators. In each entry the orbit diagonal is just the ordinary diagonal in the chamber variables. The scalar proof is then a principal-cube stopping-time argument, with two Dunkl kernel comparisons as the only new estimates. The resulting forward and backward tests are necessary and sufficient for the original Dunkl--Poisson inequality.

2605.30765 2026-06-01 quant-ph

Real-Time Quantum Error Correction System Stack: Architecture, Algorithms, and Engineering Practice

实时量子纠错系统栈:架构、算法与工程实践

Yaojian Chen, Chun-Yang Luan, Peilin Zheng, Xianghong Zeng, Jia-Yi Hou, Zhuo Fu, Yirong Jin, Fei Wang, Guangwen Yang, Dingshun Lv

AI总结 本文针对实时量子纠错中的系统级工程挑战,提出六层参考架构,并通过基准测试量化主流解码器(表面码和qLDPC码)的实时就绪度,识别关键瓶颈与架构选择。

Comments 55 pages, 10 figures

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AI中文摘要

量子纠错(QEC)正从物理可行性演示转向系统工程挑战。谷歌已在距离-5/7表面码上实现低于阈值的性能,而Riverlane和Rigetti则展示了硬件集成的低延迟反馈环路。这些里程碑表明,实时解码的核心挑战已从算法能力转向系统级工程。然而,实验室演示与可扩展容错量子计算(FTQC)之间仍存在巨大的工程差距。本白皮书探讨三个问题:(1)实时QEC的真正瓶颈在哪里:除了平均解码器速度,约束还在于QEC轮次时间、尾部延迟和端到端数据路径协调;(2)主流解码器算法的成熟度如何:我们对表面码和量子低密度奇偶校验(qLDPC)码的主要解码器进行基准测试,评估其实时就绪度;(3)我们提出什么样的系统栈:一个从综合征获取到逻辑操作的六层参考架构,包含接口定义和延迟预算模型。我们的结果量化了当前解码器性能与实时需求之间的差距,并确定了弥合该差距所需的架构选择。

英文摘要

Quantum error correction (QEC) is transitioning from physical feasibility demonstrations to systems engineering challenges. Google has achieved below-threshold performance on distance-5/7 surface codes, while Riverlane and Rigetti have demonstrated hardware-integrated low-latency feedback loops. These milestones indicate that the core challenge of real-time decoding has shifted from algorithmic capability to system-level engineering. However, a substantial engineering gap remains between laboratory demonstrations and scalable fault-tolerant quantum computing (FTQC). This white paper addresses three questions: (1) Where are the real bottlenecks in real-time QEC: beyond average decoder speed, the constraints lie in QEC round time, tail latency, and end-to-end data path coordination; (2) How mature are mainstream decoder algorithms: we benchmark the major decoders for both surface codes and quantum low-density parity-check (qLDPC) codes, evaluating their real-time readiness; (3) What system stack do we propose: a six-layer reference architecture from syndrome acquisition to logical operations, with interface definitions and latency budget models. Our results quantify the gap between current decoder performance and real-time requirements, and identify the architectural choices needed to close it.

2605.30764 2026-06-01 cond-mat.mtrl-sci cond-mat.mes-hall

Crystal Dislocations as Atomic Scale Ratchets

晶体位错作为原子尺度棘轮

Wu-Rong Jian, Yifan Wang, Wei Cai

AI总结 通过分子动力学模拟发现,面心立方镍中具有原子尺度割阶的位错在反向应力下表现出非对称迁移率,源于原子位移矢量与二阶张量本征应变的非常规耦合,挑战了经典塑性变形描述,为缺陷工程增强抗疲劳性开辟新途径。

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AI中文摘要

系统对外部刺激响应的对称性是物理学和材料科学中的一个基本概念。在微观尺度上,打破这种对称性以实现整流响应极其难以设计,并且在自然界中仍然罕见。晶体固体的传统微力学模型假设对应力的响应是对称的,即反转负载只是简单地反转缺陷速度的方向而不改变其大小。在这项工作中,我们报告了一种基于几何的原子尺度机制,打破了这种对称性。面心立方镍的分子动力学模拟表明,包含原子尺度割阶的位错在相反施加应力下表现出非对称迁移率,反转加载方向会引发显著更高的阻力。这种不对称性源于原子位移矢量与割阶运动机制的二阶张量本征应变之间的非常规耦合。由于割阶是塑性变形中普遍存在的结构,这一发现挑战了塑性变形机制的经典描述,对循环蠕变有直接影响,并为缺陷工程增强抗疲劳性开辟了新途径。

英文摘要

The symmetry of a system's response to external stimuli is a fundamental concept in physics and materials science. At the microscopic scale, breaking this symmetry to achieve a rectified response is exceptionally difficult to engineer and remains rare in nature. Conventional micromechanics models of crystalline solids assume a symmetric response to applied stress, where reversing the load simply inverts the direction of defect velocity without altering its magnitude. In this work, we report an atomic-scale, geometry-rooted mechanism that breaks this symmetry. Molecular dynamics simulations of face-centered cubic nickel reveal that dislocations containing atomic-scale jogs exhibit asymmetric mobility under opposite applied stresses, reversing the loading direction triggers significantly higher drag. This asymmetry arises from an unconventional coupling between an atomic displacement vector and the second-order tensorial eigenstrain of the jog motion mechanism. Because jogs are ubiquitous structures in plastic deformation, this discovery challenges classical descriptions of plastic deformation mechanisms, with direct implications to cyclic creep, and opens new pathways for defect engineering to enhance fatigue resistance.