arXivDaily arXiv每日学术速递 周一至周五更新
重置
全部学科分类 2060
2605.31431 2026-06-01 cs.CE

When Certainty Is Not Worth It: Capital Lock-Up and Settlement Discounting in Prediction Markets

当确定性不值得:预测市场中的资本锁定与结算折价

Jonas Gebele, Florian Matthes

AI总结 研究预测市场中结算延迟导致的定价效应,通过恢复隐含的结算折价期限结构并量化其影响,发现市场架构(如negRisk转换和收益型抵押品)可改变折价,表明定价质量内生于结算机制、抵押品生产率和资本回收设计。

详情
AI中文摘要

抵押预测市场是或有债权市场,其中经济不确定性可能在赢利债权可赎回之前消失。本文研究了这种延迟的定价效应。当抵押品在预言机结算前保持锁定时,近乎确定的美元是延迟的美元,因此价格除了包含对结果的信念外,还嵌入了依赖于期限的结算折价。我们利用已实现的结算时间从持续近乎确定的合约中恢复隐含的结算折价期限结构,并将其总结为年化结算楔差(ASW)。恢复的楔差为正、依赖于期限且随时间变化。通过这些曲线调整价格可将近乎确定的水平梯度减少约48-88%,表明原始期限模式的大部分反映了定价的结算摩擦,而不仅仅是预测误差。市场架构改变了楔差:negRisk转换通过将部分头寸回收为合成抵押品来压缩折价,而收益型抵押品通过减少锁定的机会成本来平坦化期限结构。结果表明,预测市场的定价质量内生于结算机制、抵押品生产率和资本回收设计。因此,预测市场价格通过一种金融基础设施聚合信息,该基础设施的融资条件是可测量的且经济上重要。

英文摘要

Collateralized prediction markets are contingent-claim markets in which economic uncertainty can disappear before winning claims become redeemable. This paper studies the pricing effect of that delay. When collateral remains locked until oracle settlement, a near-certain dollar is a delayed dollar, so prices embed a maturity-dependent settlement discount in addition to beliefs about outcomes. We recover an implied settlement-discount term structure from persistent near-certain contracts using realized settlement times and summarize it as an annualized settlement wedge (ASW). The recovered wedges are positive, maturity-dependent, and time-varying. Adjusting pricesby these curves reduces the near-certainty horizon gradient by roughly 48-88%, indicating that much of the raw maturity pattern reflects priced settlement frictions rather than forecast error alone. Market architecture changes the wedge: negRisk conversion compresses discounts by recycling part of the position into synthetic collateral, while yield-bearing collateral flattens the term structure by reducing the opportunity cost of lock-up. The results show that pricing quality in prediction markets is endogenous to settlement mechanics, collateral productivity, and capital-recycling design. Prediction-market prices therefore aggregate information through a financial infrastructure whose funding conditions are measurable and economically important.

2605.31430 2026-06-01 math.NA cs.NA

Spectral density estimation for normal matrices

正规矩阵的谱密度估计

Cameron Musco, Christopher Musco, Rikhav Shah, John Urschel, Nicholas West

AI总结 针对仅能通过矩阵-向量乘积查询访问的大规模正规矩阵,提出一种算法,使用m次查询即可在推土机距离O(1/m+log m/√n)内近似谱密度,并证明任何算法需要Ω(1/ε)次查询才能达到ε精度。

详情
AI中文摘要

谱密度估计问题要求给定一个$n\times n$矩阵$A$,输出一个概率测度,该测度能很好地近似$A$的特征值上的均匀分布,称为$A$的谱密度。本文考虑$A$是一个只能通过矩阵-向量乘积查询访问的大规模正规矩阵的情形。我们提供了一种算法,仅对$A$进行$m$次矩阵-向量乘积查询,并以高概率返回一个在推土机距离$O(1/m+\log m/{\sqrt n})$内接近$A$真实谱密度的测度。我们给出了一个互补的下界:任何为大矩阵产生真实谱密度的$\varepsilon$近似的算法必须进行$\Omega(1/\varepsilon)$次矩阵-向量乘积查询。即使对于更受限的实对称输入矩阵,该下界也成立。结合我们的上界,这表明对于复正规矩阵,谱密度估计本质上并不比实对称矩阵更难。

英文摘要

The spectral density estimation problem asks for an algorithm that, given an $n\times n$ matrix $A$, outputs a probability measure that is a good approximation to the uniform distribution on the eigenvalues of $A$, called the spectral density of $A$. This paper considers the setting where $A$ is a large normal matrix that is accessible only through matrix-vector product queries. We provide an algorithm that makes just $m$ matrix-vector queries to $A$ and returns, with high probability, a measure within earth mover's distance $O(1/m+\log m/{\sqrt n})$ of the true spectral density of $A$. We provide a complementary lower bound that any algorithm producing an $\varepsilon$-approximation to the true spectral density for large matrices must make $Ω(1/\varepsilon)$ matrix-vector queries. The lower bound holds even for the more restricted case of real symmetric input matrices. In combination with our upper bound, it shows that spectral density estimation is essentially no harder for complex normal matrices than for real symmetric matrices.

2605.31428 2026-06-01 physics.optics

Toroidal pulse enhanced XUV generation

环形脉冲增强极紫外辐射产生

Lu Wang, Clément Lacoste, Paul Corkum, Thomas Brabec, Zenghu Chang

AI总结 本文研究环形脉冲驱动的非线性汤姆孙散射产生极紫外辐射,发现其非分离时空场分布导致电子加速高度不对称,从而产生比高斯脉冲强2-4个数量级的极紫外发射。

详情
AI中文摘要

极紫外辐射在广泛的应用中扮演核心角色。尽管它是阿秒科学的基石,但高效产生极紫外辐射仍然极具挑战。本文研究了由环形脉冲驱动的非线性汤姆孙散射产生极紫外辐射。与传统激光脉冲不同,环形脉冲具有本质上不可分离的时空场分布。这种独特的场结构产生强烈不对称的电子加速,导致极紫外发射显著增强,比高斯脉冲产生的强2-4个数量级。我们的结果指出环形脉冲是实现紧凑型超快极紫外源和先进强场光-物质相互作用研究的一条有前景的途径。

英文摘要

Extreme ultraviolet (XUV) radiation plays a central role in a wide range of applications. Despite being a cornerstone of attosecond science, efficient XUV generation remains highly challenging. Here, we investigate XUV generation via nonlinear Thomson scattering driven by a toroidal pulse. Unlike conventional laser pulses, toroidal pulses possess intrinsically non-separable spatiotemporal field distributions. This unique field structure produces strongly asymmetric electron acceleration, resulting in substantially enhanced XUV emission that is 2-4 orders of magnitude stronger than that generated by a Gaussian pulse. Our results identify toroidal pulses as a promising route toward compact ultrafast XUV sources and advanced strong-field light-matter interaction studies.

2605.31425 2026-06-01 math.OC

Mixed-Precision GPU Acceleration for Large-Scale Minimum Enclosing Ball Problems

大规模最小包围球问题的混合精度GPU加速

Ling Liang, Lei Yang

AI总结 针对球集合的最小包围球问题,提出一种混合精度GPU优化框架,基于二阶锥规划重构和相对型不精确近端增广拉格朗日方法,通过混合精度缩减策略实现高效求解。

详情
AI中文摘要

针对计算球集合的最小包围球问题,开发了一种面向GPU的混合精度优化框架。该方法基于等价的二阶锥规划重构和相对型不精确近端增广拉格朗日方法(ripALM),该方法在求解内部子问题时仅需达到与进展相关的相对精度,同时提供高精度的优化主干。近端增广拉格朗日继承了约束可分结构:其目标、梯度、广义Hessian和乘子更新可以在GPU上作为输入球上的并行映射高效计算,随后进行归约。为了进一步提高效率,引入了混合精度归约策略。低精度ripALM运行识别近似边界附近的球,高精度ripALM运行精炼简化问题,完整的后验可行性检查检测并重新引入任何被丢弃的违反约束的球。因此,低精度仅用于筛选和热启动,而最终可行性针对原问题强制执行。数值实验表明,ripALM和混合精度ripALM实现了高精度,并且在大规模实例上比测试的基于CPU的几何软件和通用锥求解器快得多。

英文摘要

A mixed-precision GPU-oriented optimization framework is developed for computing the minimum enclosing ball of a collection of balls. The approach is built on an equivalent second-order cone programming reformulation and a relative-type inexact proximal augmented Lagrangian method (ripALM), which provides a high-accuracy optimization backbone while solving the inner subproblems only to a progress-dependent relative accuracy. The proximal augmented Lagrangian inherits a constraint-wise separable structure: its objective, gradient, generalized Hessian, and multiplier updates can be efficiently evaluated on GPUs as parallel maps over the input balls followed by reductions. To further improve efficiency, a mixed-precision reduction strategy is introduced. A low-precision ripALM run identifies balls near the approximate boundary, a high-precision ripALM run refines the reduced problem, and a full a posteriori feasibility check detects and reintroduces any violated discarded balls. Thus, low precision is used only for screening and warm starting, while the final feasibility is enforced against the original problem. Numerical experiments show that ripALM and mixed-precision ripALM achieve high accuracy and are substantially faster than the tested CPU-based geometric software and general-purpose conic solvers on large-scale instances.

2605.31424 2026-06-01 hep-ph hep-ex hep-lat

CJ26 Global QCD Analysis with Large-$x$ Jefferson Lab 6 and 12 GeV Data

CJ26 全局 QCD 分析:包含大-$x$ 杰斐逊实验室 6 和 12 GeV 数据

Alberto Accardi, Matteo Cerutti, Cynthia E. Keppel, Shujie Li, J. F. Owens, Sanghwa Park, Peter Risse

AI总结 通过首次纳入 JLab 6 GeV 全部 DIS 测量和首批 12 GeV 测量,利用 12 GeV 数据的 $Q^2$ 杠杆效应分离高扭效应与离壳核子修正,精确确定了 $n/p$ 结构函数比和 $d/u$ 价夸克比,不确定性分别降低 30-50% 和 5-10%。

Comments Feedback welcome. Results available in LHAPDF format on CJ website: https://www.jlab.org/theory/cj/pdfs

详情
AI中文摘要

我们提出 CJ26,这是新的 CTEQ-JLab 全局 QCD 分析,首次纳入了 JLab 6 GeV DIS 测量的完整套件以及首批已发表的 JLab 12 GeV 测量。该分析聚焦于大-$x$ 区域,利用 12 GeV 数据增加的 $Q^2$ 杠杆效应,独特地分离了高扭效应与离壳核子修正。这导致了对 $n/p$ 结构函数比和 $d/u$ 价夸克比的高度精确确定,不确定性分别降低了 30-50% 和 5-10%。我们强调了实验相关系统不确定性在实现这一精度中的关键作用,并提供了由此产生的 NLO PDF 和结构函数,以 LHAPDF 格式供一般使用。

英文摘要

We present CJ26, the new CTEQ-JLab global QCD analysis that incorporates for the first time the complete suite of JLab 6 GeV DIS measurements and the first published JLab 12 GeV measurements. Focused on the large-$x$ region, the analysis utilizes the increased $Q^2$ leverage of the 12 GeV data to uniquely disentangle higher-twist effects from off-shell nucleon corrections. This leads to a highly accurate determination of the $n/p$ structure function ratio and the $d/u$ valence quark ratio, with uncertainties reduced by 30-50% and 5-10%, respectively. We highlight the critical role of experimental correlated systematic uncertainties in achieving this precision and provide the resulting NLO PDFs and structure functions in LHAPDF format for general use.

2605.31422 2026-06-01 math.SG

Weinstein manifolds as cotangent buildings

Weinstein流形作为余切建筑

Daniel Álvarez-Gavela, Yakov Eliashberg, David Nadler

AI总结 引入余切建筑框架以补充和完善Weinstein handlebody理论,证明任何Weinstein流形都Weinstein同伦于一个具有余切建筑结构的流形。

详情
AI中文摘要

我们引入余切建筑框架来补充和完善Weinstein handlebody理论。Weinstein handlebody适用于对Weinstein结构进行“自下而上”的分析,而余切建筑还支持“自上而下”的分析。此外,余切建筑能够精确控制各个建筑块子集合之间的相互作用,每个建筑块都模仿带角流形的余切丛。我们的主要结果是,任何Weinstein流形都Weinstein同伦于一个具有余切建筑结构的流形。

英文摘要

We introduce the framework of cotangent buildings to complement and refine that of Weinstein handlebodies. While Weinstein handlebodies are suitable for a ``bottom-up" analysis of the Weinstein structure, cotangent buildings also enable a ``top down" analysis. Further, cotangent buildings include a precise control over the interaction of any subcollection of the various building blocks, each of which is modeled on the cotangent bundle of a manifold with corners. Our main result is that any Weinstein manifold is Weinstein homotopic to one admitting the structure of a cotangent building.

2605.31420 2026-06-01 astro-ph.GA

Enhancing Galaxy Classification with U-Net Variational Autoencoders. III. Disk-like Galaxy Identification in JWST Samples of up to redshift 4

利用U-Net变分自编码器增强星系分类:III. 在红移高达4的JWST样本中识别盘状星系

Sergey S. Mirzoyan, Arno Avagyan

AI总结 本研究将基于U-Net变分自编码器的星系分类框架扩展到红移0.5<z<4的JWST样本,通过去噪和分类流程识别出382个盘状星系,表明早期宇宙中可能存在比预期更多的盘状结构。

详情
AI中文摘要

在本系列的第三项研究中,我们将基于U-Net变分自编码器的星系分类框架扩展到一个显著更大的JWST样本,该样本覆盖红移范围$0.5 < z < 4$。我们聚焦于恒星质量超过$10^{10}\,M_\odot$的大质量系统,分析了满足这些条件的1,380个星系,并应用我们先前开发的去噪和分类流程来识别宇宙时间尺度上的盘状形态。在这一群体中,我们的分类器检测到382个盘状星系,其中一部分显示出与当前深度学习模型预期性能极限一致的不确定特征。这个扩展的数据集使我们能够在统计上有意义的高红移区域检查盘状系统的分布,包括传统上认为有序盘状结构罕见的时期。结果表明,盘状结构在广泛的红移和恒星质量范围内持续存在,表明大质量盘状星系在早期宇宙中可能比先前假设的更常见。这些发现强调了将先进去噪技术与基于机器学习的形态分析相结合,用于表征大型JWST巡天中星系群体的价值。

英文摘要

In this third study of the series, we extend our U-Net Variational Autoencoder-based galaxy classification framework to a significantly larger JWST sample spanning the redshift range $0.5 < z < 4$. Focusing on massive systems with stellar masses exceeding $10^{10}\,M_\odot$, we analyze 1,380 galaxies that satisfy these criteria and apply our previously developed denoising and classification pipeline to identify disk-like morphologies across cosmic time. Within this population, our classifier detects 382 disk-like galaxies, with a subset showing uncertain features consistent with the expected performance limits of current deep-learning models. This expanded dataset allows us to examine the distribution of disk-like systems in a statistically meaningful high-redshift regime, including epochs where well-ordered disks are traditionally expected to be rare. The results demonstrate that disk-like structures persist across a broad range of redshifts and stellar masses, suggesting that massive disks may be more common in the early universe than previously assumed. These findings emphasize the value of combining advanced denoising techniques with machine-learning-based morphological analysis for characterizing galaxy populations in large JWST surveys.

2605.31418 2026-06-01 cond-mat.stat-mech

Optimization of multisite reactions in complex compartmentalized media

复杂分区介质中多位点反应的优化

T. V. Mendes, T. Guérin

AI总结 研究随机游走者在规则扩散介质中需到达并激活位于分形亚扩散分区内的目标,通过优化分区大小最小化双位点反应时间,发现添加拥挤分区可加速弱反应性目标的反应动力学。

详情
Journal ref
Phys. Rev. E 113, 054129 (2026)
AI中文摘要

在复杂介质中,传输和几何性质深刻影响反应物随机相遇的动力学。这里,我们考虑一个随机游走者在规则扩散介质中移动,需要到达并激活位于一个以分形(受阻)亚扩散为特征的分区内的目标。我们专注于双位点反应,当两个激活事件在给定时间窗口内发生时反应结束。每次随机游走者访问目标时,激活事件以有限概率发生。对于弱反应性目标,我们证明反应时间可以通过最优分区大小最小化,甚至与没有分区的相同系统相比可以加速。我们的分析预测通过在立方晶格上随机游走者的模拟得到验证,其中分区内的一些位点在临界渗流阈值处受阻。我们的理论说明,在目标周围添加拥挤分区,即使减慢了其附近的运动,也可以加速复杂反应的动力学,特别是对于弱反应性目标。

英文摘要

In complex media, transport and geometric properties deeply influence the kinetics of random encounters between reactants. Here, we consider the situation where a random walker, moving in a regularly diffusing medium, has to reach and activate a target located inside a compartment characterized by fractal (obstructed) sub-diffusion. We focus on dual-site reactions, which end when two activation events occur within a given time window. Each activation event happens with a finite probability whenever the random walker visits the target. For weakly reactive targets, we demonstrate that the reaction time can be minimized for an optimal compartment size and can even be accelerated when compared to the same system without compartment. Our analytical predictions are validated through simulations of a random walker on a cubic lattice, where some sites inside the compartment are obstructed at the critical percolation threshold. Our theory illustrates the fact that adding a crowded compartment around a target, even if it slows down the motion in its vicinity, can accelerate the kinetics of complex reactions, especially for weakly reactive targets.

2605.31417 2026-06-01 cs.DS

An Optimal Algorithm for Binary Closest String

二元最近字符串的最优算法

Nick Fischer, Mursalin Habib

AI总结 针对二元最近字符串问题,提出一个运行时间为O*(4^d)的随机算法,匹配了细粒度下界,达到条件最优。

详情
AI中文摘要

我们重新审视二元最近字符串问题,该问题给定一组二进制字符串 $X \subseteq \{0, 1\}^n$,要求计算一个字符串,使其到 $X$ 的最大汉明距离最小。一系列工作专注于关于最优距离 $d$ 的参数化算法,从 $O^*(d^d)$ 到 $O^*(16^d)$、$O^*(9.513^d)$、$O^*(8^d)$、$O^*(6.731^d)$,再到当前已知的最优运行时间 $O^*(5^d)$ [Chen, Ma, Wang; Algorithmica '16]。我们提出一个更快的随机算法,运行时间为 $O^*(4^d)$。我们的结果匹配了最近的细粒度下界 [Abboud, Fischer, Goldenberg, Karthik C.S., Safier; ESA '23],因此是条件最优的。此外,我们的算法非常简洁。

英文摘要

We revisit the Binary Closest String problem, which asks, given a set of binary strings $X \subseteq \{0, 1\}^n$, to compute a string minimizing the maximum Hamming distance to $X$. A long line of work has focused on parameterized algorithms with respect to the optimal distance $d$, yielding a sequence of improvements from $O^*(d^d)$ through $O^*(16^d)$, $O^*(9.513^d)$, $O^*(8^d)$, $O^*(6.731^d)$ to the current best-known running time of $O^*(5^d)$ [Chen, Ma, Wang; Algorithmica '16]. We present a faster randomized algorithm running in time $O^*(4^d)$. Our result matches a recent fine-grained lower bound [Abboud, Fischer, Goldenberg, Karthik C.S., Safier; ESA '23], and is therefore conditionally optimal. As an extra benefit, our algorithm is remarkably simple.

2605.31415 2026-06-01 astro-ph.GA

COSMOS-Web: Galaxy Size and Surface Brightness Evolution at Rest-Frame 1.22 $μ$m Since $z=3$

COSMOS-Web:自z=3以来静止帧1.22 μm的星系大小和表面亮度演化

Si-Yue Yu, Andreas L. Faisst, Taotao Fang, Greta Toni, Lauro Moscardini, Maximilien Franco, Rasha M. Samir, Michaela Hirschmann, Xiaoxia Zhang, Gavin Leroy

AI总结 利用JWST COSMOS-Web巡天中15,420个星系样本,研究静止帧J波段(1.22 μm)星系大小和表面亮度在0.5≤z≤3内的演化,发现恒星形成星系和宁静星系的大小演化指数分别为β=-0.92和-1.34,表面亮度随红移增亮,演化由光度和大小的联合演化驱动。

Comments 15 pages, 4 figures, 1 table. Accepted for publication in ApjL

详情
AI中文摘要

我们利用JWST COSMOS-Web巡天中恒星质量M_⋆=10^10-10^11.5 M_⊙的15,420个星系样本,展示了静止帧J波段(1.22 μm)下星系大小和表面亮度在0.5≤z≤3内的演化,该波段追踪恒星质量分布。静止帧J波段有效半径(R_{e,J})来自先前测量,并从可用的JWST/NIRCam滤光片映射得到,而表面亮度(μ_J)则经过尘埃消光和宇宙学暗化校正。在特征质量M_⋆=5×10^10 M_⊙处,恒星形成星系的大小演化为R_{e,J} ∝ (1+z)^β,β=-0.92±0.04,介于先前报道的较平缓和较陡峭测量值之间。宁静星系演化更快,β=-1.34±0.05,与早期研究一致。在恒星形成星系中,低质量系统(10^10至10^10.5 M_⊙)的大小演化较慢(β=-0.66±0.02),而高质量系统则较快。此外,表面亮度向高红移方向增亮,标度为μ_J ∝ -2.5 log(1+z)^γ。我们发现恒星形成星系的γ=3.07±0.08,宁静星系的γ=3.70±0.08。我们还发现,大质量恒星形成星系(M_⋆>10^10.5 M_⊙)在固定红移下表现出相似的μ_J值,与质量无关。最后,我们证明观测到的表面亮度演化是由星系光度和大小的联合演化驱动的。

英文摘要

We present the evolution of galaxy size and surface brightness in the rest-frame $J$ band (1.22 $μ$m), tracing the stellar mass distribution, over $0.5 \leq z \leq 3$, using a sample of 15,420 galaxies with stellar masses $M_\star=10^{10}$-$10^{11.5}\ M_{\odot}$ from the JWST COSMOS-Web survey. The rest-frame $J$-band effective radius ($R_{e,J}$) is obtained from previous measurements and mapped from the available JWST/NIRCam filters, while the surface brightness ($μ_J$) is corrected for dust extinction and cosmological dimming. At a characteristic mass of $M_\star = 5 \times 10^{10}\ M_{\odot}$, star-forming galaxies exhibit a size evolution of $R_{e,J} \propto (1+z)^β$ with $β= -0.92 \pm 0.04$, falling between previously reported shallower and steeper measurements. Quiescent galaxies evolve more rapidly, with $β= -1.34 \pm 0.05$, consistent with earlier studies. Among star-forming galaxies, lower-mass systems ($10^{10}$ to $10^{10.5}\ M_{\odot}$) show slower ($β=-0.66\pm0.02$) size evolution compared to their higher-mass counterparts. Furthermore, the surface brightness brightens toward higher redshifts, scaling as $μ_J \propto -2.5 \log(1+z)^γ$. We find $γ= 3.07 \pm 0.08$ for star-forming galaxies and $γ= 3.70 \pm 0.08$ for quiescent galaxies. We also find that massive star-forming galaxies ($M_\star > 10^{10.5}\ M_{\odot}$) exhibit similar $μ_J$ values at fixed redshift, independent of mass. Finally, we demonstrate that the observed surface brightness evolution is driven by the combined evolution of galaxy luminosity and size.

2605.31414 2026-06-01 cs.IR

Beyond Instance-Level Alignment and Uniformity: Semantic Factor Learning for Collaborative Filtering

超越实例级对齐与均匀性:面向协同过滤的语义因子学习

Yajie Yu, Chenzhong Bin, Zhoubo Xu, Zhixin Zeng, Tongxin Xu, Cihan Xia, Jiafeng Wu

AI总结 提出语义因子增强的对齐与均匀性框架(SaFeAU),通过语义因子路由、匹配和对齐,缓解假阴性问题并捕获高阶协同信号,在稀疏数据集上优于现有方法。

Comments Accepted by KDD 2026

详情
AI中文摘要

协同过滤(CF)因其简单高效被广泛用于推荐系统(RecSys)。然而,现有CF方法遵循实例级学习范式。在实例学习阶段,大量未交互的用户-物品实例(其中物品可能是用户潜在感兴趣的)被错误地视为真正的负样本,严重限制了模型的泛化性和可扩展性。此外,主流图卷积网络(GCN)固有地存在高计算成本和过平滑问题,限制了捕获高阶连通性的能力,并在稀疏监督信号下导致泛化性能差。为解决上述局限,我们提出语义因子增强的对齐与均匀性(SaFeAU),一种新颖框架,通过语义因子增强交互实例,从而缓解假负样本标记,并使矩阵分解(MF)无需图邻域聚合即可捕获高阶CF信号。具体而言,SaFeAU包含三个紧密耦合的组件。首先,语义因子路由(SFR)将物品表示解耦为独立且全局的语义因子。基于这些因子,语义因子匹配(SFM)将未交互但与交互物品共享相同语义因子的物品识别为潜在正对,以丰富稀疏监督信号。最后,语义对对齐(SPA)对齐观测和潜在正对,同时促进用户和物品表示的均匀性。在四个稀疏真实数据集上的大量实验表明,SaFeAU在推荐精度和计算效率上均一致优于基于GCN和基于MF的最先进CF方法,验证了所提出的语义增强学习范式的有效性。

英文摘要

Collaborative filtering (CF) is widely used in recommender systems (RecSys) due to its simplicity and efficiency. However, existing CF methods follow an instance-level learning paradigm. During the instance learning stage, a large number of uninteracted user-item instances, of which items are potential interested by the user, are incorrectly treated as true negative samples resulting in a severe limitation to the generalization and scalability of models. Moreover, mainstream graph convolutional networks (GCNs) inherently suffer from high computational cost and over-smoothing issues, which limit the ability in capturing higher-order connectivity and lead to a poor generalization under sparse supervision signals. To address the above limitations, we propose Semantic Factor enhanced Alignment and Uniformity (SaFeAU), a novel framework that augments interacted instances with semantic factors, thereby mitigating false negative labeling and enabling matrix factorization (MF) to capture high-order CF signals without graph neighborhood aggregation. Specifically, SaFeAU consists of three tightly coupled components. First, Semantic Factor Routing (SFR) disentangles item representations into independent and global semantic factors. Building on these factors, Semantic Factor Matching (SFM) identifies uninteracted items, which share the same semantic factors with interacted ones, as potential positive pairs for enriching sparse supervision signals. Finally, Semantic Pairs Alignment (SPA) aligns both observed and potential positive pairs while promoting uniformity of user and item representations. Extensive experiments on four sparse real-world datasets show that SaFeAU consistently outperforms GCN-based and MF-based state-of-the-art CF methods in both recommendation accuracy and computational efficiency, confirming the effectiveness of the proposed semantic enhanced learning paradigm.

2605.31412 2026-06-01 astro-ph.GA

MAUVE-MUSE: When Metallicity Follows or Fights Star Formation -- A Mass-Dependent Inversion in Virgo Galaxies

MAUVE-MUSE: 当金属丰度跟随或对抗恒星形成——室女座星系中一个依赖于质量的反转

Rongjun Huang, Luca Cortese, Barbara Catinella, Luke J. M. Davies, Toby Brown, Andrei Ristea, Alessandro Boselli, Andrew J. Battisti, Vicente Villanueva, Kristine Spekkens, Sara L. Ellison, Daniel A. Dale, Sabine Thater, Amirnezam Amiri

AI总结 利用MAUVE-MUSE巡天数据分析14个室女座旋涡星系,发现气体金属丰度与恒星形成率面密度的关系在低恒星质量面密度区域呈反相关,在高恒星质量面密度区域呈正相关,反转点约为log10(Σ*/M⊙ kpc−2)≈7.5-8.0,并通过气体调节模型统一解释了分辨和整体关系。

Comments 20 pages, 7 figues, accepted by MNRAS

详情
AI中文摘要

尽管整体集成研究经常发现,在固定恒星质量下,高恒星形成率(SFR)的星系相对贫金属,而低SFR系统则更富金属,但在亚星系尺度上,气体相金属丰度($Z_{\rm gas}$)与恒星形成之间的相应耦合仍然缺乏约束。在本研究中,我们分析了来自MAUVE-MUSE巡天的14个室女座旋涡星系,以重新审视分辨的质量-金属丰度关系(rMZR)及其在$\sim 100$ pc尺度上对SFR面密度($\Sigma_\mathrm{SFR}$)的二次依赖性。我们构建了恒星质量面密度($\Sigma_*$)、$\Sigma_\mathrm{SFR}$和氧丰度的共空间图。MAUVE-MUSE星系遵循标准的rMZR,但当按$\Sigma_*$分箱时,我们使用O3N2校准发现$Z_\mathrm{gas}$-$\Sigma_\mathrm{SFR}$关系中存在一个依赖于质量的反转:标准的反相关仅限于低$\Sigma_*$分箱,而高$\Sigma_*$区域显示正相关,在$\log_{10}(\Sigma_*/M_\odot\,\mathrm{kpc}^{-2})\simeq 7.5$-$8.0$处反转。相关和反相关的\ion{H}{ii}区域共存于同一盘面内;仅当按$\Sigma_*$分组像素时,质量依赖性才显现。我们开发了一个空间分辨的气体调节模型,表明这种$Z_\mathrm{gas}$-$\Sigma_\mathrm{SFR}$(反)相关源于恒星形成驱动和气体供应驱动变异性之间的竞争。该框架自然地外推到整体情况,为分辨和全局关系提供了统一的解释。然而,$Z_\mathrm{gas}$-$\Sigma_\mathrm{SFR}$(反)相关的存在和强度强烈依赖于所使用的金属丰度指示剂,突显了在金属丰度标度关系中分离物理二次趋势的挑战。

英文摘要

Although globally-integrated studies often find that, at fixed stellar mass, high star formation rate (SFR) galaxies are relatively metal-poor while lower-SFR systems are more metal-rich, the corresponding coupling between gas-phase metallicity ($Z_{\rm gas}$) and star formation on sub-galactic scales remains poorly constrained. In this study, we analyse 14 Virgo spirals from the MAUVE-MUSE survey to revisit the resolved mass-metallicity relation (rMZR) and its secondary dependence on SFR surface density ($Σ_\mathrm{SFR}$) at $\sim 100$\,pc scales. We construct co-spatial maps of stellar mass surface density ($Σ_*$), $Σ_\mathrm{SFR}$, and oxygen abundance. MAUVE-MUSE galaxies follow a standard rMZR, but when binned by $Σ_*$, we find a mass-dependent inversion in the $Z_\mathrm{gas}$-$Σ_\mathrm{SFR}$ relation using O3N2 calibrations: the standard anti-correlation is confined to low-$Σ_*$ bins, while high-$Σ_*$ regions show a positive correlation, inverting at $\log_{10}(Σ_*/M_\odot\,\mathrm{kpc}^{-2})\simeq 7.5$-8.0. Correlated and anti-correlated \ion{H}{ii} regions coexist within the same discs; the mass dependence emerges only when grouping spaxels by $Σ_*$. We develop a spatially resolved gas-regulator model showing this $Z_\mathrm{gas}$-$Σ_\mathrm{SFR}$ (anti-)correlation arises from competition between star-formation-driven and gas-supply-driven variability. This framework naturally extrapolates to the integrated scenario, providing a unified explanation for resolved and global relations. However, the presence and strength of the $Z_\mathrm{gas}$-$Σ_\mathrm{SFR}$ (anti-)correlation depend strongly on the metallicity indicator used, highlighting the challenge of disentangling physical secondary trends within metallicity scaling relations.

2605.31411 2026-06-01 cond-mat.mtrl-sci cond-mat.mes-hall

Odd-Parity Magnons

奇宇称磁子

Pu Zhang, Sun-Bo Xie, Junxi Yu, Yichen Liu, Cheng-Cheng Liu

AI总结 本文提出在共线反铁磁体中实现奇宇称磁子的机制,通过自旋点群分类和对称性分析,揭示了光或环流诱导的p波和f波磁子分裂,并预言了拓扑磁子相变及手性边缘态。

Comments 9+20 pages, 4+5 figures, 1 table

详情
AI中文摘要

磁子作为电中性的自旋激发,可以在没有焦耳热的情况下传输自旋信息,因此为低功耗自旋电子学提供了一个有前景的平台。然而,在共线磁体中,有效时间反演对称性禁止奇宇称磁子能带分裂。在这里,我们提出奇宇称磁子,并建立了一个在共线反铁磁体中实现它们的通用机制。我们通过识别主要分裂类型及其对称性允许的基函数,提供了二维共线反铁磁体中奇宇称磁子分裂的完整自旋点群分类。该分类可作为寻找奇宇称磁子的实用指南。我们表明,打破有效时间反演对称性(例如通过圆偏振光或环流)可以诱导高度可调的$p$波和$f$波磁子分裂。在双层系统中,动态调制可以驱动拓扑磁子相变,伴随着手性边缘模式和磁子热霍尔电导率的突然跳跃。特定材料的第一性原理计算进一步证明了该机制在真实范德华反铁磁体中的可行性。我们的研究将奇宇称磁子确定为一类新的自旋激发,并为奇宇称磁子和超快光控拓扑磁子器件提供了理论基础。

英文摘要

Magnons, as charge-neutral spin excitations, can transport spin information without Joule heating and therefore offer a promising platform for low-power spintronics. However, in collinear magnets, the effective time-reversal symmetry forbids odd-parity magnon band splitting. Here we propose odd-parity magnons and establish a general mechanism for realizing them in collinear antiferromagnets. We provide a complete spin-point-group classification of odd-parity magnon splitting in two-dimensional collinear antiferromagnets by identifying the leading splitting types and their symmetry-allowed basis functions. This classification serves as a practical guide for searching for odd-parity magnons. We show that breaking effective time-reversal symmetry, for example by circularly polarized light or loop currents, can induce highly tunable $p$- and $f$-wave magnon splitting. In bilayer systems, the dynamical modulation can drive a topological magnon phase transition, accompanied by chiral edge modes and an abrupt jump in the magnon thermal Hall conductivity. Material-specific first-principles calculations further demonstrate the feasibility of this mechanism in real van der Waals antiferromagnets. Our study identifies the odd-parity magnons as a new class of spin excitations and provides a theoretical foundation for odd-parity magnons and ultrafast optically controlled topological magnonic devices.

2605.31409 2026-06-01 quant-ph

Fidelity bounds for spin-dependent kicks with pulsed lasers

脉冲激光自旋依赖冲量的保真度界限

C. Sagaseta, H. Liu, V. D. Vaidya, C. R. Viteri, J. J. García-Ripoll, E. Torrontegui

AI总结 通过解析方法和数值模拟,表征了快速光学拉曼脉冲激发囚禁离子超精细量子比特中自旋依赖冲量的控制参数,发现有限脉冲持续时间是主要误差源,并给出了实现高保真度SDK的定量设计规则。

Comments 15 pages, 6 figures

详情
AI中文摘要

用快速光学拉曼脉冲激发囚禁离子超精细量子比特,能够实现比陷阱周期更快的纠缠门,且量子比特具有长相干时间,适用于实用量子计算。实现高保真度快速双量子比特门需要高质量的自旋依赖冲量(SDK),这是其基本构建模块。在这里,我们表征了控制参数(包括拉曼频率差、脉冲到达时间、兰姆-迪克参数、温度、脉冲宽度和SDK时间),以最大化单离子SDK的性能,适用于涉及少量快速脉冲的实验协议。我们通过解析方法和数值模拟证明,在常用于非保真度优化的模型中,有限脉冲持续时间是误差的主要来源,对于纳秒级SDK,其贡献超过质心运动数个数量级。对于具有≥10个固定幅度、等间距、皮秒脉冲的方案,在纳秒量级的SDK时间内可以实现低于10^{-3}的低非保真度。这些结果为利用当前脉冲激光技术实现具有竞争力的SDK保真度提供了定量设计规则,为亚微秒级囚禁离子量子纠缠操作奠定了基础。

英文摘要

Excitation of trapped-ion hyperfine qubits with fast optical Raman pulses enables faster-than-trap-period entangling gates with qubits of long coherence time for practical quantum computation. Achieving high-fidelity fast two-qubit gates requires high-quality spin-dependent kicks (SDKs), which form their fundamental building blocks. Here, we characterize the control parameters (including Raman frequency difference, pulse arrival times, Lamb--Dicke parameter, temperature, pulse width, and SDK time) that maximize the performance of single-ion SDKs for protocols compatible with performed experiments involving a small number of fast pulses. We demonstrate through analytical methods and numerical simulations that, within the model commonly used for infidelity optimization, finite pulse duration is the dominant source of error, exceeding the contribution of secular motion by orders of magnitude for nanosecond-scale SDKs. Low infidelities -- below $10^{-3}$ for schemes with $\gtrsim10$ fixed-amplitude, equispaced, picosecond pulses -- are achievable in SDK times on the order of nanoseconds. These results provide quantitative design rules for achieving competitive SDK fidelities with current pulsed-laser technology, laying the foundation for sub-microsecond trapped-ion quantum entangling operations.

2605.31407 2026-06-01 math.DS

A variational principle for metric mean dimension via lower Brin-Katok local entropy

通过下Brin-Katok局部熵的度量平均维数的变分原理

Ruxi Shi

AI总结 本文证明了下Brin-Katok局部熵与Katok覆盖熵之间的有限尺度比较,并结合Katok型变分原理,得到了度量平均维数的下Brin-Katok局部熵变分原理。

Comments 11 pages, 1 figure

详情
AI中文摘要

我们证明了下Brin-Katok局部熵与Katok覆盖熵之间的有限尺度比较。设$(\mathcal{X},d,T)$是一个紧致度量拓扑动力系统,$\mu$是遍历的。那么,对于每个$\varepsilon>0$和每个$\delta\in(0,1)$,有$$ h^K_\mu(6\varepsilon,\delta)\leq \underline h^{BK}_\mu(\varepsilon). $$将此估计与通常的度量平均维数的Katok型变分原理相结合,得到了下Brin-Katok局部熵的相应变分原理。

英文摘要

We prove a finite-scale comparison between lower Brin-Katok local entropy and Katok covering entropy. Let $(\mathcal{X},d,T)$ be a compact metric topological dynamical system and let $μ$ be ergodic. Then, for every $ε>0$ and every $δ\in(0,1)$, $$ h^K_μ(6ε,δ)\leq \underline h^{BK}_μ(ε). $$ Combining this estimate with the usual Katok-type variational principle for metric mean dimension gives the corresponding variational principle with lower Brin-Katok local entropy.

2605.31406 2026-06-01 cs.DB

AIM: A practical approach to automated index management for SQL databases

AIM:一种实用的SQL数据库自动索引管理方法

Ritwik Yadav, Satyanarayana R. Valluri, Mohamed Zaït

AI总结 提出AIM自动索引管理系统,通过配置化方法识别SQL数据库中的有效二级索引,优化资源利用,并在生产环境中验证了快速收敛、减少查询优化器依赖和无回归保证等特性。

详情
Journal ref
2023 IEEE 39th International Conference on Data Engineering (ICDE), Anaheim, CA, USA, 2023, pp. 3349-3362
AI中文摘要

本文描述了AIM(自动索引管理器),一个可配置的索引管理系统,用于识别SQL数据库中的有效二级索引,以高效利用可用资源(如CPU、I/O和存储)。该系统已在支持生产系统的数千个数据库上得到验证。借助AIM,数据库的物理设计能够适应工作负载的变化。我们阐述了AIM的端到端设计,同时指出了与设计选择相关的保证和权衡。AIM的一些显著特性包括:即使在推荐宽复合索引时也能快速收敛,减少对查询优化器的依赖,以及为生产工作负载提供“无回归”保证。AIM的每个索引推荐都附有基于指标的解释,使验证机器驱动的更改更加容易。AIM是少数大规模部署在生产数据库上的工业级索引推荐引擎之一。实验结果表明,AIM能够快速识别最有效的索引,且生成的物理设计接近最优。

英文摘要

This paper describes AIM (Automatic Index Manager), a configurable index management system, which identifies impactful secondary indexes for SQL databases to efficiently use available resources such as CPU, I/O and storage. It has been validated on thousands of databases which support production systems. With AIM, the physical design of the database adapts itself to the changes in the workload.We lay out the end to end design of AIM while calling out the guarantees and tradeoffs associated with our design choices. Some of the salient features of AIM include fast convergence even while recommending wide composite indexes, reduced reliance on the query optimizer and a "no regression" guarantee for production workloads. Each index recommendation from AIM is accompanied with a metrics driven explanation, making it easier to verify machine driven changes.AIM is one of the few industrial strength index recommendation engines that is deployed on production databases at a large scale. The experimental results show that AIM is quick in identifying the most effective indexes and the resulting physical design is close to optimal.

2605.31403 2026-06-01 math.NT

The Bogomolov property for $p$-supercuspidal eigenforms

$p$-超尖点特征形式的Bogomolov性质

Andrea Conti, Pietro Piras, Lea Terracini

AI总结 本文通过构造度量不等式,证明了与$p$处局部分量为超尖点的特征形式相关的adelic Galois表示所确定的$\mathbb Q$的代数扩张的Weil高度下界,即Bogomolov性质。

Comments 20 pages

详情
AI中文摘要

我们证明了Weil高度的下界,即所谓的Bogomolov性质,适用于由某些特征形式(其在素数$p$处的局部分量为超尖点)的adelic Galois表示所确定的$\mathbb Q$的代数扩张。为此,我们给出了一种在$\mathbb Q$上且在$p$处有限分歧的域的$p$-adic Lie扩张上构造度量不等式的方法。

英文摘要

We prove a lower bound on the Weil height, the so-called Bogomolov property, for the algebraic extensions of $\mathbb Q$ cut out by the adelic Galois representations attached to certain eigenforms whose local component at a prime $p$ is supercuspidal. To this end, we give a method for constructing metric inequalities over $p$-adic Lie extensions of fields over $\mathbb Q$ that are finitely ramified at $p$.

2605.31398 2026-06-01 math.CO

Universality for rainbow oriented cycles in perturbed digraphs

扰动有向图中彩虹有向圈的普适性

Robert A. Krueger, David Staudinger

AI总结 研究随机扰动有向图在均匀n边着色下,高概率同时包含所有长度和定向的彩虹有向圈,通过Montgomery分布吸收法证明。

Comments 35 pages, 7 figures

详情
AI中文摘要

随机扰动有向图是一个$n$顶点有向图,其所有出度和入度均为$n$的线性阶,并且额外随机添加了线性数量(依赖于度数)的随机边。我们证明,若其边被均匀地染成$n$种颜色,则随机扰动有向图以高概率同时包含每个可能长度的所有定向的彩虹有向圈。这是Araujo、Balogh、Krueger、Piga和Treglown在无色情形下的工作,以及Katsamaktsis、Letzter和Sgueglia关于一致定向生成圈的工作的共同推广。我们的证明使用了Montgomery的分布式吸收方法。

英文摘要

A randomly perturbed digraph is an $n$-vertex directed graph with all out- and in-degrees linear in $n$, to which a linear number (depending on the degree) of random edges have been randomly added. We show that randomly perturbed digraphs whose edges have been colored uniformly with $n$ colors have a rainbow copy of every orientation of every possible length cycle, simultaneously, with high probability. This is a common generalization of work of Araujo, Balogh, Krueger, Piga, and Treglown in the uncolored setting and Katsamaktsis, Letzter, and Sgueglia for consistently oriented spanning cycles. Our proof uses Montgomery's distributive absorption method.

2605.31397 2026-06-01 math.DG math.MG

Constant mean curvature surfaces in the sub-Lorentzian Heisenberg group

子洛伦兹海森堡群中的常平均曲率曲面

Samuël Borza, Andrea Pinamonti, Omar Zoghlami

AI总结 本文研究了子洛伦兹海森堡群中具有常水平平均曲率的曲面,通过体积保持径向变分推导了水平面积的第一变分公式,并完整分类了光滑的boost对称常平均曲率曲面,发现了一族非零常平均曲率的光滑非因果boost对称曲面,推测其为等周问题的解。

Comments 48 pages, 4 figures

详情
AI中文摘要

我们研究了子洛伦兹海森堡群中的常水平平均曲率曲面。我们推导了体积保持径向变分下水平面积的第一变分公式,并证明光滑的等周候选者在远离特征集处具有常水平平均曲率。然后,我们给出了光滑boost对称常平均曲率曲面的完整分类:它们的特征集、因果行为以及环境子洛伦兹等距类。从这一分类中,我们挑选出一族具有非零常平均曲率的光滑、非因果、boost对称曲面。作为未来双曲线外部区域上的双叶图,这一族是Pansu气泡的自然子洛伦兹类比,并使我们推测它给出了子洛伦兹海森堡群中的等周最大化者。

英文摘要

We study constant horizontal mean curvature surfaces in the sub-Lorentzian Heisenberg group. We derive the first-variation formula for horizontal area under volume-preserving radial variations and show that smooth isoperimetric candidates have constant horizontal mean curvature away from the characteristic set. We then give a complete classification of smooth boost-symmetric constant mean curvature surfaces: their characteristic sets, causal behaviour, and ambient sub-Lorentzian isometry classes. From this classification, we single out a family of smooth, acausal, boost-symmetric surfaces with nonzero constant mean curvature. Written as a two-sheeted graph over the exterior of a future hyperbola, this family is a natural sub-Lorentzian analogue of the Pansu bubbles and leads us to conjecture that it gives the isoperimetric maximisers in the sub-Lorentzian Heisenberg group.

2605.31396 2026-06-01 eess.SY cs.SY

Current Practices in Electricy Demand and Charging Scheduling for On-Road Electric Fleet Operations: An Industry-Wide Review

当前公路电动车队运营中的电力需求与充电调度实践:行业综述

Joost Commandeur, Bart De Schutter, Neil Yorke-Smith

AI总结 本文通过灰色文献分析,综述了电动卡车车队运营中数字系统的现状,识别了关键趋势与差距,以指导未来研究与发展。

详情
AI中文摘要

公路车队物流的电气化有望改善空气质量、降低噪音排放、带来重大气候效益、通过使用本地发电提高能源灵活性,并减少对进口燃料的依赖。然而,电池电动汽车可能带来内燃机车辆所没有的运营规划挑战,包括异构充电速度、暴露于波动的电价以及基础设施稀缺。管理这些复杂性需要平衡成本效益和鲁棒性的解决方案,并得到交通与电力系统之间部门耦合的支持。本文通过灰色文献分析,回顾了电动卡车车队管理中用于运营决策的数字系统的现状,借鉴了从业者导向的来源,如行业报告、公司文档和技术博客,这些反映了实际实践和发展。我们识别了关键趋势和差距,为未来研究和发展提供指导。

英文摘要

The electrification of on-road fleet logistics promises improved air quality, lower noise emissions, major climate benefits, increased energy flexibility through the use of locally generated electricity and reduced dependence on imported fuels. However, battery electric vehicles can introduce operational planning challenges not present with internal combustion engine vehicles, including heterogeneous charging speeds, exposure to volatile electricity prices, and scarcity in infrastructure. Managing these complexities requires solutions that balance cost efficiency and robustness, supported by sector coupling between transport and electricity systems. This paper reviews the current state of digital systems for operational decision-making in electric fleet management through a grey literature analysis, drawing on practitioner-oriented sources such as industry reports, company documentation, and technical blogs that reflect real-world practices and developments. We identify key trends and gaps, providing insights to guide future research and development.

2605.31395 2026-06-01 cond-mat.mtrl-sci

Direct Observation of Chemical Short-Range Order in CoCrNi Alloy Using Neutron Diffraction

利用中子衍射直接观察CoCrNi合金中的化学短程有序

Vinícius P. Bacurau, Camilo Salvador, Guilherme C. Stumpfa, Angelo F. Andreolli, Caroline B. Stocoa, Eric M. Mazzer, Lewis Owen, Yifan Cao, Rodrigo Freitas, Daniel Miracle, Francisco G. Coury

AI总结 通过中子衍射实验证实了CoCrNi合金中存在化学短程有序,并利用原子模拟和散射分析揭示了其结构特征与形成机制。

详情
AI中文摘要

本研究提供了通过中子衍射识别的等原子CoCrNi合金中化学短程有序(CSRO)的实验证据。该现象表现为在Q = 1.85 A-1处出现明显的漫散射峰,其强度在热力学有利于CSRO发展的条件下增加,例如在748 K下长时间时效(100小时和240小时)或在稍高温度(798 K)下短时间时效(24小时)。通过积分漫散射强度测量有序度,发现气雾化样品(即CSRO最少的样品)仍显示出约70%的CSRO水平,该水平是在748 K下时效240小时的样品(即本研究中产生的CSRO最多的样品)中观察到的。预测性原子模拟再现了漫散射峰的存在和位置,而二维快速傅里叶变换(FT-2D)分析表明,<001>晶带轴内的(1 1/2 0)反射源于与D022、Pt2Mo和D1a构型相关的某些结构投影。互补的小角中子散射(SANS)测量识别出富镍的盘状区域,半径约为11 Å,厚度约为1 Å,与纳米级CSRO的特征长度尺度一致。这些发现表明,CSRO是CoCrNi体系固有的且能量上有利的特征,即使在快速凝固下也能保持稳定,并通过低温时效进一步增强。中子衍射与原子模拟的结合使用为探测多主元合金(MPEAs)中的局域有序现象提供了框架。

英文摘要

This study provides experimental evidence of chemical short-range order (CSRO) in the equiatomic CoCrNi alloy, identified through neutron diffraction. The phenomenon manifests as a distinct diffuse peak at Q = 1.85 A-1, the intensity increases under thermodynamically favorable conditions for CSRO development such as prolonged aging (100 h and 240 h) at 748 K or shorter aging (24 h) at slightly higher temperature (798 K). The degree of ordering was measured by integrating the diffuse scattering intensity, revealing that the gas-atomized sample, i.e. the sample with the least amount of CSRO, still displays approximately 70% of the CSRO level observed in the sample subsequently aged for 240 h at 748 K, i.e. the sample with the highest amount of CSRO produced in this study. Predictive atomistic simulations reproduced both the presence and position of the diffuse peak, while two-dimensional fast Fourier transform (FT-2D) analyses indicated that reflections at (1 1/2 0) within the <001> zone axis originate from some structural projections associated with like D022, Pt2Mo and D1a motifs. Complementary small-angle neutron scattering (SANS) measurements identified Ni-rich, disk-shaped domains with radii of approximately 11 A and thicknesses of about 1 A, consistent with nanoscale CSRO characteristic length scale. These findings demonstrate that CSRO is an intrinsic and energetically favorable feature of the CoCrNi system, remaining stable even under rapid solidification and further enhanced by low-temperature aging. Combined use of neutron diffraction and atomistic modeling provides a framework for probing local ordering phenomena in multi-principal element alloys (MPEAs).

2605.31394 2026-06-01 stat.ME stat.AP

A Dynamic Latent Space Model for Healthcare Mobility Networks: the Italian National Health Service case

医疗流动网络的动态潜空间模型:以意大利国家卫生服务为例

Cecilia Manente, Marco Alfò, Silvia D'Angelo

AI总结 提出一种贝叶斯动态潜空间模型,用于分析意大利地方卫生机构间髋关节置换手术的患者流动网络,揭示医疗系统结构演化、COVID-19影响及区域不对称性。

详情
AI中文摘要

医疗流动——患者在其居住地以外寻求治疗——是分散式卫生系统中不平等和财政失衡的主要来源。在意大利,地方卫生机构(ASL)之间患者流动的持续南北不对称加剧了国家卫生服务内部的现有差距;然而,这些流动在次区域层面的结构组织与时间动态仍知之甚少。我们提出一种针对有向加权网络的贝叶斯动态潜空间模型,采用障碍负二项似然,并将其应用于2018-2024年间109个意大利ASL的髋关节置换手术医疗流动行政出院记录。该模型联合处理了零膨胀、过度离散和网络依赖性,同时通过乘性发送者和接收者效应捕捉方向异质性,并通过适当的暴露项控制地域规模差异。应用于意大利医疗流动数据时,该模型揭示了医疗系统的演化几何结构,量化了COVID-19大流行造成的干扰,并揭示了向外倾向和ASL吸引力的结构性不对称。该框架为动态医疗流动网络的统计分析提供了灵活工具,与区域医疗服务的监测和评估直接相关。

英文摘要

Healthcare mobility -- patients seeking treatment outside their territory of residence -- represents a major source of inequality and financial imbalance in decentralised health systems. In Italy, persistent north-south asymmetries in patient flows among Local Health Authorities (ASLs) have reinforced existing disparities within the National Health Service; yet the structural organisation and temporal dynamics of these flows remain poorly understood at the sub-regional level. We propose a Bayesian dynamic latent space model for directed weighted networks with a hurdle negative binomial likelihood, and apply it to administrative discharge records on mobility for hip replacement procedures among 109 Italian ASLs over 2018-2024. The model jointly addresses excess zeros, overdispersion and network dependence, while capturing directional heterogeneity through multiplicative sender and receiver effects and controlling for differences in territorial size via an appropriate exposure term. Applied to Italian mobility data, the model reveals the evolving geometry of the healthcare system, quantifies the disruption induced by the COVID-19 pandemic, and uncovers structural asymmetries in outward propensity and ASLs attractiveness. The framework provides a flexible tool for the statistical analysis of dynamic healthcare mobility networks with direct relevance to the monitoring and evaluation of territorial healthcare provision.

2605.31392 2026-06-01 cs.CE

On limitations of polyconvexity

关于多凸性的局限性

Dominik K. Klein, Rogelio Ortigosa, Heinrich T. Roth, Karl A. Kalina, Jesús Martínez-Frutos, Markus Kästner, Oliver Weeger

AI总结 本文分析了多凸性本构建模在理论上可能施加过度约束导致精度受限的原因,并通过两种非多凸Mooney-Rivlin势的解析椭圆性保证以及两种多凸物理增强神经网络模型的实验,评估了其实际局限性,最后总结了多凸性本构建模的优势、局限性和缓解策略。

详情
AI中文摘要

多凸性本构建模具有吸引力,因为它能保证数值模拟的稳定性,并改善材料模型的泛化行为。然而,在某些应用中,多凸性公式在再现底层真实材料响应方面表现不佳,这实际上可能阻碍其实际使用。本文针对这一问题,研究了多凸性本构建模的局限性。主要贡献如下:(1) 我们分析了多凸性在某些情况下可能施加过度约束,从而限制本构模型可实现精度的理论原因。为此,我们为两种非多凸的Mooney-Rivlin型势提供了解析椭圆性保证。(2) 我们使用两种代表性公式研究了多凸性物理增强神经网络本构模型的实际局限性:基于结构张量不变量的模型和基于符号奇异值的模型。在均匀化微结构材料数据集上评估了它们的性能,并在有限元模拟中评估了其预测能力。(3) 总体而言,我们概述了多凸性本构建模的优势、局限性和缓解策略。

英文摘要

Polyconvex constitutive modeling is attractive as it guarantees stability of numerical simulations and can improve the generalization behavior of material models. However, in certain applications, polyconvex formulations perform poorly in reproducing the underlying ground truth material response, which can effectively preclude their practical use. In this work, we address this issue and investigate the limitations of polyconvex constitutive modeling. The main contributions of this paper are as follows: (1) We analyze the theoretical reasons why polyconvexity may, in some cases, impose overly restrictive constraints that limit the achievable accuracy of constitutive models. Thereby, we provide analytical ellipticity guarantees for two non-polyconvex Mooney-Rivlin type potentials. (2) We investigate the practical limitations of polyconvex physics-augmented neural network constitutive models using two representative formulations: models using structural tensor-based invariants and models using signed singular values. Their performance is evaluated on datasets obtained from homogenized microstructured materials, and their predictive capabilities are assessed in finite element simulations. (3) Overall, we provide an overview of benefits, limitations, and mitigation strategies of polyconvex constitutive modeling.

2605.31390 2026-06-01 math.OA math.DS math.SP

Five shades of KMS: Statistical properties in the spectral geometry of Cuntz--Krieger algebras

KMS的五种色调:Cuntz-Krieger代数谱几何中的统计性质

Dimitris Michail Gerontogiannis, Magnus Goffeng

AI总结 本文研究拓扑马尔可夫链和Cuntz-Krieger代数的非交换几何中的谱不变量,通过log-Laplacian构建的谱三元组证明了统计特征值渐近、局部热迹渐近、局部Weyl定律以及Connes迹定理的类比,所有局部渐近由Cuntz-Krieger代数上规范作用的Kubo-Martin-Schwinger态控制。

Comments 37 pages

详情
AI中文摘要

我们研究了拓扑马尔可夫链和Cuntz-Krieger代数的非交换几何中出现的谱不变量。它们的非交换几何由基于log-Laplacian的谱三元组描述,已知这些谱三元组具有非平凡的指标理论和奇异的量子对称性。我们证明了统计特征值渐近、局部热迹渐近、局部Weyl定律以及Connes迹定理的类比。在所有情况下,局部渐近由Cuntz-Krieger代数上规范作用的Kubo-Martin-Schwinger态控制。

英文摘要

We study spectral invariants arising in the noncommutative geometry of topological Markov chains and Cuntz--Krieger algebras. Their noncommutative geometry is described by spectral triples built from log-Laplacians, which are known to have non-trivial index theory and exotic quantum symmetries. We prove statistical eigenvalue asymptotics, local heat trace asymptotics, local Weyl laws, and an analogue of Connes' trace theorem. In all cases the local asymptotics are governed by the Kubo--Martin--Schwinger state of the gauge action on the Cuntz--Krieger algebra.

2605.31389 2026-06-01 cs.PL cs.CR

Neuroforger: certified violation witnesses for smart contracts verification via LLMs

Neuroforger: 通过大语言模型为智能合约验证生成认证违规见证

Massimo Bartoletti, Enrico Lipparini

AI总结 针对自然语言属性歧义和LLM回答无正确性保证的问题,提出一种结合LLM、类型检查和具体执行的工作流,通过引入扩展Solidity的抽象类型形式规范语言,生成并验证违规见证(反例)。

详情
AI中文摘要

近期的大语言模型(LLMs)具备了推理能力,使其在预测智能合约是否遵守特定属性方面表现良好,这为传统基于形式化方法的智能合约验证提供了一种补充途径。然而,LLMs在此类场景中的应用存在两个主要问题:1)用自然语言表达的属性本质上是模糊的;2)LLMs返回的答案没有正确性保证。在本文中,我们通过以下方式同时解决了这两个问题:1)引入一种新的形式规范语言,该语言通过抽象类型扩展了Solidity;2)设计了一个工作流,将LLMs与类型检查和具体执行相结合,以生成并验证违规见证(即反例)。关键思想是将规范表示为带有(存在量化)抽象类型变量的Solidity测试;将这些变量实例化为具体值(正确类型)将测试具体化为目标属性的可执行反例(PoC)。我们在工具Neuroforger中实现了该流程,并在从文献中提取的智能合约验证数据集上进行了实验评估,获得了有希望的结果,证明了其在现实场景中的潜在适用性。

英文摘要

Recent large language models (LLMs) incorporate reasoning capabilities that allow them to perform well in predicting whether a smart contract respects a certain property, suggesting a complementary approach to traditional formal-methods-based techniques for smart contract verification. However, the application of LLMs in such context has two major issues: 1) properties expressed in natural language are intrinsically ambiguous, and 2) answers returned by LLMs have no guarantee of correctness. In this paper, we address both issues simultaneously by: 1) introducing a new formal specification language that extends Solidity with abstract types, and 2) designing a workflow that combines LLMs with type checking and concrete execution to generate and validate violation witnesses (i.e., counterexamples). The key idea is to represent a specification as a Solidity test with (existentially quantified) variables of abstract type; finding an instantiation of these variables to concrete values (of the correct type) concretizes the test into an executable counterexample (PoC) for the target property. We implemented our procedure in the tool Neuroforger, experimentally evaluating it on a smart-contract verification dataset drawn from literature, obtaining promising results that demonstrate its potential applicability in the wild.

2605.31385 2026-06-01 physics.flu-dyn

Algebraic models of plane Couette equilibria

平面库埃特流平衡态的代数模型

Pratik P. Aghor, John F. Gibson

AI总结 通过对称性和运动学约束,利用经典近似方法推导出平面库埃特流的常微分方程模型,其平衡态由二次代数方程组控制,在低维空间中近似已知平衡态并随维数增加收敛,发现了七个对称群中的十六个不同平衡解分支。

详情
AI中文摘要

最近对过渡剪切流中弱不稳定平衡态、行波和周期轨道的计算表明,低雷诺数湍流可以采用时空动力系统方法。许多不变解已通过高维直接数值模拟精确计算,但关于解的数量、组织方式或哪组解最能表征流动,我们知之甚少。本文提出了一个在低维背景下解决这些问题的框架。利用经典近似方法并利用对称性和运动学约束,我们推导了平面库埃特流的常微分方程模型,其平衡态由二次代数方程组控制。这些代数系统的解在仅17维中近似已知的平面库埃特流平衡态,并随着维数增加收敛到已知解。对系统的搜索在七个不同对称群中产生了十六个不同的平衡解分支。这些结果表明,封闭剪切流的平衡态和行波解由二次方程组的代数结构组织。此外,微分方程和无散基提供了平面库埃特流的显式、封闭形式且收敛的动力系统表示。

英文摘要

Recent computations of weakly unstable equilibria, traveling waves, and periodic orbits in transitional shear flows suggest a spatiotemporal, dynamical-systems approach to low-Reynolds turbulence. Many invariant solutions have been computed precisely using high-dimensional direct numerical simulations, but little is known about how many solutions exist, how they are organized, or which sets of solutions best characterize the flow. In this paper we present a framework for addressing these questions in a low-dimensional context. Using classical approximation methods and exploiting symmetries and kinematic constraints, we derive ordinary differential equation models of plane Couette flow whose equilibria are governed by systems of quadratic algebraic equations. Solutions of these algebraic systems approximate known equilibria of plane Couette flow in as few as 17 dimensions and converge toward the known solutions as dimension increases. Searches over the systems produce sixteen distinct equilibrium solution branches in seven different symmetry groups. These results suggest that the equilibrium and traveling-wave solutions of closed shear flows are organized by the algebraic structure of systems of quadratic equations. Additionally, the differential equations and divergence-free basis provide explicit, closed-form, and convergent dynamical-systems representations of plane Couette flow.

2605.31384 2026-06-01 math.RT

Descent and finite permutation resolutions for discrete groups

离散群的下降与有限置换分解

Juan Omar Gómez, Luca Pol

AI总结 对于具有有限维proper作用模型空间的离散群和有限整体维数的交换Noether环,证明了投射kG-模的同伦范畴、Mazza-Symonds定义的kG-模的稳定模范畴以及具有有限迷向的置换kG-模的导出范畴可以下降至有限子群,并应用该结果推广了Balmer-Gallauer的定理。

Comments 35 pages, comments welcome!

详情
AI中文摘要

设$G$是一个离散群,具有有限维proper作用模型空间,$k$是一个有限整体维数的交换Noether环。在此设定下,我们证明了投射$kG$-模的同伦范畴、Mazza-Symonds定义的$kG$-模的稳定模范畴以及具有有限迷向的置换$kG$-模的导出范畴可以下降至有限子群。作为应用,我们证明任何$FP_\infty$型的$kG$-模都是某个模的收缩核,该模具有由有限生成的具有有限迷向的$\natural$-置换模构成的有限分解,推广了Balmer-Gallauer的一个结果。

英文摘要

Let $G$ be a discrete group with a finite-dimensional model for the classifying space for proper actions, and let $k$ be a commutative Noetherian ring of finite global dimension. In this setting, we prove that the homotopy category of projective $kG$-modules, the stable module category of $kG$-modules as defined by Mazza-Symonds, and the derived category of permutation $kG$-modules with finite isotropy, admit descent to finite subgroups. As an application, we show that any $kG$-module of type $FP_\infty$ is a retract of a module that admits a finite resolution by finitely generated $\natural$-permutation modules with finite isotropy, generalizing a result of Balmer-Gallauer.

2605.31383 2026-06-01 math.GT

Extendable mapping classes of knotted surfaces obtained by rim surgery in $S^4$

在 $S^4$ 中通过边缘手术得到的打结曲面的可扩展映射类

Weizhe Niu

AI总结 研究在 $S^4$ 中通过沿非分离曲线进行标准无扭边缘手术得到的打结曲面的可扩展映射类子群,并利用结群的子午线-经线刚性条件精确计算该子群。

Comments 31 pages. Comments are welcome!

详情
AI中文摘要

设 $Σ_g^0\subset S^4$, $g\ge 3$ 为标准无结闭可定向曲面,$a\subsetΣ_g^0$ 为可定向非分离曲线。对于非平凡结 $J\subset S^3$,令 $Σ_{g,a,J}\subset S^4$ 为沿 $a$ 进行普通无扭边缘手术得到的曲面。假设 $J$ 的结群满足子午线-经线刚性条件,我们精确计算可扩展映射类子群:\[ E(Σ_{g,a,J})= \operatorname{Stab}_{\operatorname{Mod}(Σ_g)}(q_0)\cap \operatorname{Stab}_{\operatorname{Mod}(Σ_g)}([a]), \] 其中 $q_0$ 是标准嵌入的 Rokhlin 二次型,$[a]\in H_1(Σ_g;\mathbb Z)$ 是可定向同调类。

英文摘要

Let $Σ_g^0\subset S^4$, $g\ge 3$, be the standard unknotted closed oriented surface, and let $a\subsetΣ_g^0$ be an oriented nonseparating curve. For a nontrivial knot $J\subset S^3$, let $Σ_{g,a,J}\subset S^4$ be the surface obtained by ordinary untwisted rim surgery along $a$. Assuming a meridian-longitude rigidity condition on the knot group of $J$, we compute the extendable mapping-class subgroup exactly: \[ E(Σ_{g,a,J})= \operatorname{Stab}_{\operatorname{Mod}(Σ_g)}(q_0)\cap \operatorname{Stab}_{\operatorname{Mod}(Σ_g)}([a]), \] where $q_0$ is the Rokhlin quadratic form of the standard embedding and $[a]\in H_1(Σ_g;\mathbb Z)$ is the oriented homology class.

2605.31382 2026-06-01 physics.ins-det

Development of a Multi-Purpose Optical TPC for Neutron-Induced Reaction Studies at SARAF

用于SARAF中子诱导反应研究的多用途光学时间投影室

R. Felkai, M. Borysova, L. Moleri, J. Pienaar, D. Vartsky, A. Breskin, I. Mor, L. Weissman, S. Bressler

AI总结 开发一种基于CF4闪烁气体混合物的光学时间投影室(OTPC),结合快速光电探测器和高速光学读出,实现带电粒子轨迹的3D重建,以解决天体物理相关能量下中子反应截面约束不足的问题。

Comments 7 pages, 6 figures. Accepted for publication in PoS(TAUP2025)

详情
AI中文摘要

中子诱导反应在恒星和宇宙大爆炸核合成模型中起着核心作用。然而,许多截面在天体物理相关能量下仍然约束不足。为了满足这些需求,我们正在开发一种多用途光学时间投影室(OTPC),优化用于Soreq应用研究加速器设施(SARAF)即将到来的高强度、飞行时间中子束的精确中子反应研究。该探测器结合了充满CF4基闪烁气体混合物的漂移室、用于快速闪烁探测的光电探测器以及用于雪崩诱导二次闪烁的高速光学读出,以实现带电粒子轨迹的完整3D重建。一个原型系统已经组装并测试。这使我们能够系统地表征Ar/CF4气体混合物中的电子漂移速度、电荷和光放大以及α粒子轨迹的2D光学成像。这些研究指导了设计用于SARAF运行的更大、完全集成的OTPC系统。同时,我们正在探索先进的图像传感器以进一步提高跟踪分辨率。我们报告了原型的近期进展,并概述了迈向完整系统调试的下一步计划。

英文摘要

Neutron-induced reactions play a central role in stellar and Big Bang nucleosynthesis models. Yet many of the cross sections remain poorly constrained at astrophysically relevant energies. To address these needs, we are developing a multi-purpose Optical Time Projection Chamber (OTPC) optimized for precision neutron-reaction studies at the Soreq Applied Research Accelerator Facility (SARAF) upcoming high-intensity, time-of-flight neutron beam. The detector combines a drift chamber filled with CF4-based scintillating gas mixtures, fast photodetectors for prompt scintillation detection, and high-speed optical readout of avalanche-induced secondary scintillation to enable full 3D reconstruction of charged-particle tracks. A prototype system has been assembled and tested. This has enabled systematic characterization of electron drift velocity, charge and light amplification, and 2D optical imaging of alpha-particle tracks in an Ar/CF4 gas mixture. These studies guide the design of a larger, fully integrated OTPC system intended for operation at SARAF. In parallel, we are exploring advanced image sensors to further enhance tracking resolution. We report on recent progress with the prototype and outline the next steps toward commissioning the full system.

2605.31379 2026-06-01 quant-ph cs.IT math-ph math.IT math.MP

Rényi divergences and binary state discrimination error exponents for fermionic quasi-free states

费米子拟自由态的Rényi散度与二元状态区分误差指数

Milán Mosonyi, Gábor Maróti-Zareczky

AI总结 针对双无限费米子链上的平移不变且规范不变的拟自由态,给出了多种正则化Rényi散度的显式公式,并分析了单模与多模情形下的渐近行为及误差概率的超指数衰减。

Comments 38 pages

详情
AI中文摘要

二元独立同分布量子状态区分中两类错误概率之间的权衡关系可以通过Petz型和夹层型Rényi散度的单副本公式表示。在非独立同分布情形下,误差指数通常可以用正则化Rényi散度表示,而这些散度一般没有显式公式。本文考虑双无限费米子链上的一类状态——平移不变且规范不变的拟自由态,并给出了这些状态之间多种正则化Rényi散度的显式公式,包括$(α,z)$、对数欧几里得、最大、测量以及最近引入的积分Rényi散度。我们证明,当每个格点只有一个模式时,情形渐近经典化,所有不同类型的正则化Rényi散度相等;而当每个格点有多个模式时,非对易性在正则化下持续存在,且对于任意固定的$α$,正则化Rényi $(α,z)$-散度通常对不同的$z$参数给出不同的正则化值。我们还推广了[Bunth, Maróti, Mosonyi, Zimborás, Lett.~Math.~Phys.~113:(7), 2023]中的构造到每个格点多个模式的情形,得到了一大类具有区分误差概率超指数衰减的状态。

英文摘要

The trade-off relations between the two types of error probabilities in binary i.i.d. quantum state discrimination can be expressed by single-copy formulas in terms of the Petz-type and the sandwiched Rényi divergences of the two states representing the two hypotheses. In the non-i.i.d. setting, the error exponents can usually be expressed in terms of regularized Rényi divergences, which do not admit explicit formulas in general. Here, we consider a class of states, translation-invariant and gauge-invariant quasifree states on doubly infinite fermionic chains, and give explicit formulas for a wide range of regularized Rényi divergences between such states, including $(α,z)$, log-Euclidean, maximal, measured, and the recently introduced integral Rényi divergences. We show that the case where there is a single mode at each lattice site becomes asymptotically classical, with all the different types of regularized Rényi divergences being equal, while in the case of multiple modes per site, non-commutativity persists under regularization, and for any fixed $α$, the regularized Rényi $(α,z)$-divergences give different regularized values for different $z$ parameters in general. We also generalize a previous construction from [Bunth, Maróti, Mosonyi, Zimborás, Lett.~Math.~Phys.~113:(7), 2023] to the case of multiple modes per lattice site to obtain a large class of states exhibiting super-exponential decay of the discrimination error probabilities.