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2603.19839 2026-06-05 nucl-th astro-ph.HE hep-ph

A dual description of quarks and baryons: Quarkyonic matter within a relativistic quark model

双描述的夸克与重子:基于相对论夸克模型的夸克性物质

Tsuyoshi Miyatsu, Myung-Ki Cheoun, Koichi Saito

AI总结 本文基于双夸克性图景和夸克-介子耦合模型,研究了夸克性物质的性质,发现核相互作用会改变方程状态的高密度行为和声速,且夸克性模型比非相互作用高斯夸克性模型更早达到夸克饱和。

Comments 4 papes, 4 figures, 2 table, proceedings of The 2025 International Conference on the Structure of Baryons (Baryons 2025), Jeju, Korea, 10-14 Nov, 2025; v2: minor changes

Journal ref J.Subatomic Part.Cosmol. 6 (2026) 100411

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AI中文摘要

我们通过将双夸克性图景与夸克-介子耦合(QMC)模型结合,研究了相对论夸克模型中的夸克性物质。利用相对论高斯夸克波函数构造夸克性QMC(QQMC)模型,并研究对称核物质和纯中子物质的性质。我们发现夸克饱和密度对核子大小参数敏感地依赖,并且核相互作用定量地改变了方程状态(EoS)的高密度行为和声速。特别是,QQMC模型比非相互作用高斯夸克性模型(GQ)模型更早达到夸克饱和,表明核相互作用增强了夸克性区域的EoS刚性。

英文摘要

We investigate quarkyonic matter within a relativistic quark model by combining the dual quarkyonic picture with the quark-meson coupling (QMC) model. Using relativistic gaussian quark wavefunctions for the nucleon, we construct the quarkyonic QMC (QQMC) model and study the properties of symmetric nuclear matter and pure neutron matter. We find that the quark saturation density depends sensitively on the nucleon size parameter and that nuclear interactions quantitatively modify the high-density behavior of the equation of state (EoS) and the sound velocity. In particular, the QQMC model yields an earlier onset of quark saturation than the noninteracting gaussian quarkyonic (GQ) model, indicating that nuclear interactions enhance the stiffening of the EoS in the quarkyonic regime.

2603.24988 2026-06-05 physics.optics

Pulse Breathing Dynamics in a Mode-Locked Laser measured via SHG autocorrelation

模式锁激光中脉冲呼吸动力学的测量方法:通过SHG自相关

S. Kannan, S. Padmanaban, X. T. Yan, Y. S. Athreya, K. G. H. Baldwin, S. S. Hodgman, A. G. Truscott

AI总结 本文通过SHG自相关分析提出一种统计自相关方法,揭示了模式锁激光中脉冲呼吸动力学的W形特征,为超稳振荡器设计提供了诊断能力。

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AI中文摘要

模式锁激光中的脉冲到脉冲波动从根本上限制了从光学频率梳到超连续谱生成的应用。尽管时间抖动已被广泛表征,但脉冲幅度和宽度波动仍难以实验测量。本文提出了一种统计自相关方法,通过二次谐波生成自相关的Fano因子分析,揭示了增强的Fano轮廓中的特征W形,这是脉冲形状动力学的标志,无法通过时间平均波动观测到。将该方法应用于两个商用被动模式锁振荡器,分别在1030 nm和1045 nm处运行,具有不同的性能规格,测量到脉冲宽度波动分别为3.2(1) fs和2.86(2) fs。这两种独立仪器在不同激光平台上对技术进行了交叉验证。这种诊断能力为识别和抑制特定的呼吸机制提供了可能,为需要高精度频率计量的超稳振荡器设计铺平了道路。

英文摘要

Pulse-to-pulse fluctuations in mode-locked lasers fundamentally limit applications from optical frequency combs to supercontinuum generation. While timing jitter has been extensively characterized, pulse amplitude and width fluctuations remain less accessible experimentally. We present a statistical autocorrelation method that demonstrates pulse breathing dynamics through Fano factor analysis of second-harmonic generation autocorrelation. This reveals a characteristic W-shape in the enhanced Fano profile, a signature of pulse shape dynamics that is invisible to time-averaged fluctuations. Applying this method to two commercially available passively mode-locked oscillators operating at 1030 nm and 1045 nm, with different performance specifications, we measure pulse width fluctuations of 3.2(1)\,fs and 2.86(2)\,fs respectively. The two independent instruments serve as a cross-validation of the technique across different laser platforms. This diagnostic capability opens the door to identifying and suppressing specific breathing mechanisms, paving the way for the design of ultra-stable oscillators required for precision frequency metrology.

2603.24827 2026-06-05 physics.chem-ph cond-mat.mtrl-sci physics.comp-ph

Permeation of hydrogen across graphdiyne: molecular dynamics vs. quantum simulations and role of membrane motion

氢气通过graphdiyne的渗透:分子动力学与量子模拟以及膜运动的作用

Mateo Rodríguez, José Campos-Martínez, Marta I. Hernández

AI总结 研究通过分子动力学模拟和量子模拟比较氢气通过graphdiyne膜的渗透过程,探讨膜运动对渗透性能的影响。

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AI中文摘要

先前基于电子结构计算和分子动力学(MD)模拟的研究表明,graphdiyne(GDY)是一种非常适用于分离不同物种气体混合物中少量分子的二维膜。然而,当轻分子参与GDY亚纳米孔的渗透过程时,量子效应可能在动态中起作用。在本工作中,我们报告了严格的量子力学计算以及等效的MD模拟,研究H2分子通过静态GDY膜的传输,作为验证这些方法应用于此类问题的案例。所使用的力场基于改进的Lennard-Jones公式,参数通过准确的ab initio计算优化。发现尽管在感兴趣的温度范围内(250至350 K)量子效应仍然显著,MD模拟能够合理地再现量子渗透率与温度的依赖关系。此外,通过量子校正的Feynman-Hibbs有效势计算的MD渗透率提供了一个下限,而纯经典方法提供了一个上限,从而导致渗透结果的可信范围被良好限定。此外,在MD模拟中可以纳入GDY层的热运动,在这种情况下,由于GDY原子振动导致渗透势垒显著降低,观察到渗透率的增强。因此,建模膜运动对于提供可靠的气体传输特性模拟至关重要。

英文摘要

Previous research based on electronic structure calculations and molecular dynamics (MD) simulations have demonstrated that graphdiyne (GDY) is a very suitable two-dimensional membrane for the separation of small molecules in a gas mixture of different species. However, quantum effects may play a role in the dynamics of these permeation processes when light molecules are the ones involved in the crossing of the GDY subnanometric pores. In this work we report rigorous quantum-mechanical calculations together with equivalent MD simulations of the transport of H2 molecules through a static GDY membrane, as a case study for the validity of the application to these problems of classical dynamics. The force fields employed are based on an improved Lennard-Jones formulation, with parameters optimized by means of accurate ab initio calculations. It is found that, although quantum effects are still significant at the temperatures of interest (between 250 and 350 K), MD simulations are able to reasonably reproduce the dependence of the quantum permeances with the temperature. Moreover, MD permeances computed with quantum corrections through Feynman-Hibbs effective potentials provide a lower bound to quantum permeances, while the pure classical counterpart gives an upper bound, thus leading to a well delimited range of confidence of the permeation results. Furthermore, within MD simulations it is possible to incorporate the thermal motion of the GDY layer and in this situation it is observed an enhancement of the permeances with respect to the fixed membrane case, due to a significant reduction of the permeation barriers when the GDY atoms are allowed to vibrate. It seems apparent therefore, that modeling the membrane motion is crucial to provide reliable simulations of the gas transport features.

2603.23460 2026-06-05 math.AT math.MG

Function-Rips complexes in persistent homotopy theory: Stability and persistent Latschev theorems

函数-里普斯复形在持久同伦论中的应用:稳定性与持久拉茨谢夫定理

Steve Oudot, Lukas Waas

AI总结 本文研究了函数-里普斯复形在持久同伦论中的稳定性及持久拉茨谢夫定理,通过结合固定尺度的里普斯复形与底层空间的滤波数据,推广了拉茨谢夫和哈斯曼的经典结果到具有滤波函数的空间中。

Comments This is the upcoming full journal version, whereas the previous one served to present additional material for the SoCG conference proceedings version

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AI中文摘要

哈斯曼和拉茨谢夫的经典结果表明,维蒂里斯-里普斯复形可以从格罗莫夫-哈迪斯距离附近有限度量空间中恢复流形的同伦类型。本文为具有滤波函数的度量空间证明了持久同伦版本的这些定理。研究的核心对象是所谓的持久同伦类型,即结合固定尺度的里普斯参数与底层空间滤波数据的过滤简单复形。利用CAT(κ)几何和持久简单同伦理论的技术,本文将拉茨谢夫和哈斯曼的定理推广到具有滤波函数和同伦交错的空问中。一个关键成分是一个新的同伦稳定性定理。已知固定尺度的函数-里普斯构造在函数格罗莫夫-哈迪斯距离和同伦交错距离下不具有全局稳定性。本文证明,对于适当的里普斯参数选择,在这样的配对(M,f)中,M是一个具有上界曲率的完整度量空间,f是一个利普希茨连续的多变量函数时,该构造仍然是稳定的。

英文摘要

Classical results of Hausmann and Latschev show that Vietoris-Rips complexes can recover the homotopy type of a manifold, even from finite metric spaces that are nearby in Gromov-Hausdorff distance. We prove persistent homotopical versions of these theorems for metric spaces equipped with filtration functions. The central object of study is the so-called persistent homotopy type of the function-Rips complex, a filtered simplicial complex that combines a fixed Rips scale with the filtration data on the underlying space. Using techniques from CAT($κ$)-geometry and persistent simplicial homotopy theory, we generalize Latschev's and Hausmann's theorems to the setting of spaces with filtration functions and homotopical interleavings. A fundamental ingredient is a new homotopical stability theorem. The fixed-scale function-Rips construction is known not to be globally stable with respect to function Gromov-Hausdorff distance and homotopical interleaving distance. Here, we show that it is nevertheless stable for appropriate choices of the Rips parameter at such pairs $(M,f)$ for which $M$ is a complete metric space of curvature bounded above, and $f$ is a Lipschitz continuous multivariate function.

2511.15427 2026-06-05 econ.EM stat.ME

Tractable Estimation of Nonlinear Panels with Interactive Fixed Effects

可计算的非线性面板模型交互固定效应估计

Andrei Zeleneev, Weisheng Zhang

AI总结 本文提出了一种计算高效的方法,用于估计非线性面板模型中的交互固定效应,该方法在理论上等价于Chen等人(2021)提出的估计器,避免了高维非凸优化问题,适用于大规模非线性面板数据。

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AI中文摘要

在线性面板模型中,交互固定效应通常被控制。尽管文献中已存在非线性模型的类似固定效应(FE)估计器(Chen, Fernandez-Val和Weidner, 2021),但其在应用研究中使用有限,因为其实施涉及解决高维非凸问题。本文通过提供一个计算效率高的新估计器来补充Chen等人(2021)的理论分析,该估计器在渐近上等价于他们的估计器。与之前提出的FE估计器不同,我们的估计器避免了解高维非凸优化问题,并且可以在大规模非线性面板中可行计算。我们提出的方法包括两个步骤。第一步是使用核范数正则化(NNR)凸化优化问题,获得参数的初步估计,包括固定效应。然后,我们使用标准梯度下降法在这些初步估计上找到原始优化问题的全局解。为了使我们的方法在实践中易于应用,我们还提出了特定的数值算法来解决涉及的优化问题,建立了其收敛性,并在我们的R包NNRPanel中提供了高效的实现。

英文摘要

Interactive fixed effects are routinely controlled for in linear panel models. While an analogous fixed effects (FE) estimator for nonlinear models has been available in the literature (Chen, Fernandez-Val and Weidner, 2021), it sees much more limited use in applied research because its implementation involves solving a high-dimensional non-convex problem. In this paper, we complement the theoretical analysis of Chen, Fernandez-Val and Weidner (2021) by providing a new computationally efficient estimator that is asymptotically equivalent to their estimator. Unlike the previously proposed FE estimator, our estimator avoids solving a high-dimensional non-convex optimization problem and can be feasibly computed in large nonlinear panels. Our proposed method involves two steps. In the first step, we convexify the optimization problem using nuclear norm regularization (NNR) and obtain preliminary NNR estimators of the parameters, including the fixed effects. Then, we find the global solution of the original optimization problem using a standard gradient descent method initialized at these preliminary estimates. To make our method readily applicable in practice, we also propose specific numerical algorithms for solving the involved optimization problems, establish their convergence, and provide their efficient implementation in our R package NNRPanel.

2603.22979 2026-06-05 math.AG

The Weil Decoration of the Horrocks-Mumford Bundle

Horrocks-Mumford丛的Weil装饰

Klaus Altmann, Andreas Hochenegger, Frederik Witt

AI总结 本文研究了正常代数簇中反射性秩一sheaf与Weil除子之间的关系,并将其推广到任意秩的反射性sheaf及其所谓的Weil装饰,同时定义并研究了Horrocks-Mumford丛的一个自然推广。

Comments 21 pages, minor errors corrected, more concise presentation

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AI中文摘要

对于一个正常代数簇,我们将反射性秩一sheaf与Weil除子之间的关系推广到任意秩的反射性sheaf以及所谓的Weil装饰。作为应用,我们定义并研究了一个著名Horrocks-Mumford丛的自然推广。

英文摘要

For a normal algebraic variety we generalise the relation between reflexive rank one sheaves and Weil divisors to reflexive sheaves of arbitrary rank and so-called Weil decorations. As an application, we define and study a natural generalisation of the celebrated Horrocks-Mumford bundle.

2603.22950 2026-06-05 stat.AP

Higher-Order Multivariate Environmental Influences in Structural Health Monitoring

结构健康监测中的高阶多变量环境影响

Lizzie Neumann, Philipp Wittenberg, Jan Gertheiss

AI总结 本文研究了环境条件对结构健康监测输出统计量的影响,提出两种方法(随机森林和核方法)来识别和量化多变量干扰效应,发现核方法更准确但随机森林更稳健且易于解释。

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AI中文摘要

系统输出如本征频率或应变数据,常用于结构健康监测(SHM),不仅对损伤反应,还依赖于环境条件。在尝试纠正这些混杂效应时,通常(至少隐含地)假设只有预期值,即均值输出受环境条件影响。然而,对实际SHM数据的评估表明,环境条件可能不仅影响均值输出,还影响更高阶的统计矩,特别是输出量的方差以及它们之间的协方差和相关性,如不同模式的本征频率或不同位置的应变传感器。为了解决这些问题,我们讨论了两种方法来识别和量化对输出协方差和相关性的多变量混杂效应:随机森林和非参数、基于核的方法。我们在人工和实际SHM数据上比较了这两种竞争方法,发现基于核的方法具有更高的准确性,但随机森林产生的估计值更稳健,有时更容易解释。

英文摘要

System outputs such as eigenfrequencies or strain data, often used in structural health monitoring (SHM), not only react to damage but also depend on environmental conditions. When trying to correct for these confounding effects, it is often (at least implicitly) assumed that only the expected, i.e., mean, output values are affected by environmental conditions. However, the evaluation of real-world SHM data indicates that environmental conditions may influence not only the mean output but also higher-order statistical moments, particularly the variances of and the covariances and correlations between the output quantities, such as eigenfrequencies of different modes or strain sensors at different locations. To address these issues, we discuss two approaches for identifying and quantifying multivariate confounding effects on output covariances and correlations: a random forest and a nonparametric, kernel-based approach. We compare the two competing methods on both artificial and real-world SHM data, finding that the kernel-based approach achieves higher accuracy, but the random forest produces estimates that are more robust and sometimes easier to interpret.

2603.22568 2026-06-05 cond-mat.mes-hall

Magnetic Weyl semimetals: Interplay of band topology and magnetism

磁性韦尔半导体:带拓扑与磁性的相互作用

Akihiro Ozawa, Yasufumi Araki, Koji Kobayashi, Kentaro Nomura

AI总结 本文研究磁性韦尔半导体中带拓扑与磁性相互作用的物理机制,总结了其在磁电响应、自旋动力学以及磁输运现象中的核心贡献。

Comments 60 pages, 22 figures. In this version, some figures have been omitted due to copyright restrictions

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AI中文摘要

我们回顾了磁性韦尔半导体在理论和实验方面的最新发展,重点研究其电子带拓扑与磁性相互作用所产生的电磁响应。我们首先介绍了韦尔半导体中电子的基本拓扑性质,并概述了其带拓扑特征现象,如反常霍尔效应和手性磁效应。列举了表现出磁性韦尔半导体态的材料,包括铁磁有序、反铁磁有序等。讨论了其磁性的可能机制与韦尔电子的联系。非均匀磁结构和磁化动态预计会与韦尔电子产生拓扑相互作用,表现为自旋推力和自旋扭矩。我们还回顾了如域壁磁电阻等磁输运现象,通过介观尺度计算研究。最后,提及磁性韦尔半导体中研究的自旋输运性质。本文回顾的韦尔电子拓扑性质不仅对基础物理重要,也对低损耗电子和自旋电子器件的应用具有潜力。

英文摘要

We review recent theoretical and experimental developments in magnetic Weyl semimetals, focusing on the electromagnetic responses emerging from the interplay of their electronic band topology and magnetism. We begin by introducing the fundamental topological properties of the electrons in Weyl semimetals, and provide an overview of the characteristic phenomena arising from their band topology, such as the anomalous Hall effect and chiral magnetic effect. The materials exhibiting the magnetic Weyl semimetal state, with ferromagnetic ordering, antiferromagnetic ordering, etc., are listed. The possible mechanisms for their magnetism are discussed in connection with the Weyl electrons. Non-uniform magnetic textures and magnetization dynamics are expected to exhibit a topological interplay with the Weyl electrons, manifesting as spinmotive force and spin torques. We also review the magnetotransport phenomena such as domain wall magnetoresistance, studied by mesoscopic scale calculations. Finally, we mention the spin transport properties studied in magnetic Weyl semimetals. The topological nature of Weyl electrons reviewed here is important not only for fundamental physics, but also for the potential application to low-dissipative electronics and spintronics devices.

2603.22223 2026-06-05 hep-ph

The energy-momentum tensor in a classical model of the electron

量子电动力学中电子经典模型的能量动量张量

Grace Gardella, Mira Varma, Peter Schweitzer

AI总结 本文通过Bialynicki-Birula的经典电子模型,正确推导了量子电动力学中电荷粒子能量动量张量(EMT)小t展开中的主导非解析项,并讨论了最近提出的正则化质子D项概念。

Comments 9 pages, 3 figure files

Journal ref Phys. Rev. D 113 (2026) 116008

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AI中文摘要

我们展示,通过Bialynicki-Birula的经典电子模型,可以正确推导出量子电动力学中电荷粒子能量动量张量(EMT)小t展开中的主导非解析项。基于所采用的精确可解模型的清晰性,我们还评论了最近提出的一种正则化质子D项的概念。

英文摘要

We show that the leading non-analytic terms in the small-t expansion of the energy momentum tensor (EMT) form factors of an electrically charged particle in QED can be correctly derived in a classical model of the electron by Bialynicki-Birula. Based on the lucidity of the employed exactly solvable model, we comment also on the recently proposed concept of a regularized proton D-term.

2603.20617 2026-06-05 econ.TH

The AI Layoff Trap

AI裁员陷阱

Brett Hemenway Falk, Gerry Tsoukalas

AI总结 本文通过竞争性任务模型,研究AI自动化导致的企业间需求外部性如何引发过度裁员,并提出庇古税作为解决方案。

Comments 63 pages, 4 figures, 2 tables

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AI中文摘要

如果AI取代人类工人的速度快于经济重新吸收他们的速度,就有可能侵蚀企业赖以生存的消费者需求。我们表明,仅仅知道这一点并不足以让企业停止这一过程。在一个转型经济的竞争性任务模型中,每个企业获得自动化的全部成本节约,但只承担其在产品市场上创造的需求损失的一小部分;其余部分落在竞争对手身上。这种需求外部性使理性企业陷入自动化军备竞赛,取代工人的程度远超集体最优水平。由此造成的损失既损害工人也损害企业所有者。更多的竞争和“更好”的AI会放大这种过度;工资调整和自由进入无法消除它。资本所得税、员工股权、全民基本收入、技能提升或科斯谈判也无法消除。而庇古式的自动化税可以。结果表明,政策不仅应应对AI劳动力替代的后果,还应解决驱动它的竞争性激励。

英文摘要

If AI displaces human workers faster than the economy can reabsorb them, it risks eroding the very consumer demand firms depend on. We show that knowing this is not enough for firms to stop it. In a competitive task-based model of a transitioning economy, each firm captures the full cost saving from automation but bears only a fraction of the demand loss it creates in the product market; the rest falls on rivals. This demand externality traps rational firms in an automation arms race, displacing workers well beyond what is collectively optimal. The resulting loss harms both workers and firm owners. More competition and ``better'' AI amplify the excess; wage adjustments and free entry cannot eliminate it. Neither can capital income taxes, worker equity, universal basic income, upskilling, or Coasean bargaining. A Pigouvian automation tax can. The results suggest that policy should address not only the aftermath of AI labor displacement but also the competitive incentives that drive it.

2601.10162 2026-06-05 math.FA

Toeplitz Operators on Quaternionic Fock Spaces

在四元数福克空间上的Toeplitz算子

Zhaopeng Lin, Yufeng Lu, Chao Zu

AI总结 本文研究了四元数福克空间上具有正测度符号和切片函数符号的Toeplitz算子的有界性和紧性,通过归一化再生核和对称盒子平均提出判据,同时引入全局四元数福克空间定义具有实值测度符号的Toeplitz算子。

Comments 35 pages

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AI中文摘要

我们刻画了具有正测度符号和切片$\mathrm{BMO}^1$符号的四元数福克空间上Toeplitz算子的有界性和紧性。对于正测度符号,我们利用归一化再生核和对称盒子平均导出判据;而对于切片$\mathrm{BMO}^1$符号,刻画依赖于Berezin变换。我们进一步引入一个全局四元数福克空间$F_α^p$,通过将切片正则函数积分到$\mathbb{H}$的所有复切片上,定义具有实值测度符号的Toeplitz算子,该空间与标准切片基于四元数福克空间是等norm的。在Hilbert空间情况$p=2$下,存在一个切片无关的正交投影,允许以统一的方式定义具有实值测度符号和切片函数符号的Toeplitz算子。

英文摘要

We characterize boundedness and compactness of Toeplitz operators on quaternionic Fock spaces with positive measure symbols and slice-function symbols in \(\mathrm{BMO}^1\). For positive measure symbols, we derive criteria using normalized reproducing kernels and symmetric box averages, while for slice \(\mathrm{BMO}^1\) symbols, the characterizations rely on the Berezin transform. We further introduce a global quaternionic Fock space \(F_α^p\) to define Toeplitz operators with real-valued measure symbols; this space is built by integrating slice regular functions over all complex slices of \(\mathbb{H}\) and is norm-equivalent to the standard slice-based quaternionic Fock space. In the Hilbert space case \(p=2\), a slice-independent orthogonal projection exists, which allows us to define Toeplitz operators with real-valued measure symbols and slice-function symbols in a unified way.

2601.00532 2026-06-05 physics.space-ph math.OC

Solar Cruiser Disturbance Torque Estimation and Predictive Momentum Management

太阳帆扰动扭矩估计与预测动量管理

Ping-Yen Shen, Ryan J. Caverly

AI总结 本文提出了一种结合扰动扭矩估计的模型预测控制(MPC)框架,用于NASA太阳帆任务的动量管理。研究重点在于利用主动质量转换器(AMT)和反射率控制装置(RCDs)作为动量管理执行器,通过卡尔曼滤波实时估计未建模的扰动扭矩,提升动量管理的可靠性和性能。

Comments Submitted to Advances in Space Research

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AI中文摘要

本文提出了一种结合扰动扭矩估计的模型预测控制(MPC)框架,用于NASA太阳帆任务的动量管理。太阳帆代表了大尺寸太阳帆技术的重要进展,其中包括主动质量转换器(AMT)和反射率控制装置(RCDs)作为动量管理执行器的创新应用。这些执行器的耦合特性在开发鲁棒的动量管理控制器方面带来了挑战。尽管最近的文献已经探索了MPC在太阳帆动量管理中的应用并取得了有希望的结果,但需要精确了解作用在太阳帆上的扰动扭矩。本文通过使用卡尔曼滤波来提供实时估计未建模的扰动扭矩,解决了这一问题。此外,本文中使用的动力学模型相比先前的工作具有关键的保真度增强,包括太阳帆的四反应轮组装以及其中质心与压力中心之间的偏移。此外,还进行了更现实的操作场景,包括在受姿态影响的太阳辐射力和扭矩下跟踪大角度 slew 操纵,以进一步验证所提出的方法相对于先前工作的有效性。仿真结果表明,所提出的策略在超出当前最先进方法操作范围的 slew 操纵中成功管理角动量增长。扰动扭矩估计的纳入被证明显著提高了所提出MPC方法的可靠性和性能。这项工作为太阳帆的动量管理能力设定了新的基准,并为利用AMT和/或RCDs的其他太阳帆的基于MPC的动量管理铺平了道路。

英文摘要

This paper presents a novel disturbance-torque-estimation-augmented model predictive control (MPC) framework to perform momentum management on NASA's Solar Cruiser solar sail mission. Solar Cruiser represents a critical step in the advancement of large-scale solar sail technology and includes the innovative use of an active mass translator (AMT) and reflectivity control devices (RCDs) as momentum management actuators. The coupled nature of these actuators has proven challenging in the development of a robust momentum management controller. Recent literature has explored the use of MPC for solar sail momentum management with promising results, although exact knowledge of the disturbance torques acting on the solar sail was required. This paper amends this issue through the use of a Kalman filter to provide real-time estimation of unmodeled disturbance torques. Furthermore, the dynamics model used in this paper incorporates key fidelity enhancements compared to prior work, including Solar Cruiser's four-reaction-wheel assembly and the offset between its center of mass and center of pressure. More realistic operation scenarios involving the tracking of large angle slew maneuvers under attitude-dependent solar radiation force and torque are also performed to further validate the proposed method compared to prior work. Simulation results demonstrate that the proposed policy successfully manages angular momentum growth under slew maneuvers that exceed the operational envelope of the current state-of-the-art method. The inclusion of the disturbance torque estimate is shown to greatly improve the reliability and performance of the proposed MPC approach. This work establishes a new benchmark for Solar Cruiser's momentum management capabilities and paves the way for MPC-based momentum management of other solar sails making use of an AMT and/or RCDs.

2601.01421 2026-06-05 econ.TH

A measure of choice irrationality based on opposite judgements

基于对立判断的选择非理性度量

Angelo Enrico Petralia

AI总结 本文提出一种基于偏好与其对立面之间折衷的选择非理性度量,刻画决策者将偏好中前几个备选方案逆序移至末尾的程度,并给出该度量的充要条件及极端折衷行为的刻画。

Comments arXiv admin note: substantial text overlap with arXiv:2408.01317

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AI中文摘要

在许多选择情境中,决策者采用的标准是其偏好与对立面之间的折衷。根据这种折衷,决策者偏好中排名靠前的i个备选方案被逆序移至底部。这一模式允许定义基于折衷的非理性程度,量化决策者在选择中所采纳的折衷程度。本文给出了刻画该指数的充要条件。我研究了显示最低非理性程度的不可理性化选择,并完全识别了通过最小化对立判断之间的折衷来解释决策者选择的偏好。这些数据集涵盖了一些已知的选择偏差,如次优程序和避免劣势选项。我提供了表现出最严重折衷的选择行为的简单刻画,并证明该子类几乎包含所有选择。最后,刻画了其他几种折衷度量,并与先前确定的得分进行了比较。

英文摘要

In many choice settings the decision maker (DM) adopts a criterion which is a mediation between her preference, and its opposite. According to such compromise, the first i alternatives on top of the DM's taste are moved, in reverse order, to the bottom. This pattern allows to define the compromise-based degree of irrationality, which quantifies the extent of the mediation embraced by the DM in her choice. Necessary and sufficient conditions characterizing this index are singled out. I investigate non rationalizable choices that display the lowest degree of irrationality, and I fully identify the preferences that explain the DM's picks by a minimal mediation between opposite judgments. These datasets account for some well known selection biases, such as second-best procedures, and the handicapped avoidance. I offer a simple characterization of the choice behavior that exhibits the most severe compromise, and I show that this subclass comprises almost all choices. Finally, some alternative measures of compromise are characterized, and compared with the score previously determined.

2603.17689 2026-06-05 hep-ph

Neutrino mass variables in 3 active and 2 sterile neutrino scenario

三活性和二 sterile 中微子场景中的中微子质量变量

Srubabati Goswami, Hemanth M., Debashis Pachhar, N Rajeev

AI总结 研究探讨了在三活性和二 sterile 中微子框架下,中微子质量变量对宇宙学和实验室观测的影响,分析了不同质量顺序方案的限制,并评估了未来实验如KATRIN、Project 8和LEGEND-1000对超出最小三味模型的物理的补充作用。

Comments 19 pages, 5 figures, 9 tables ; (accepted in PRD )

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AI中文摘要

三味中微子振荡框架成功解释了大多数实验结果,但短基线和长基线实验中持续的异常提示可能存在额外的轻 sterile 状态。特别是,eV尺度的 sterile 中微子受到LSND和MiniBooNE结果的启发,而亚eV尺度的 sterile 状态则被提出以解决T2K--NOνA张力和太阳中微子能谱预期上升的缺失。这些 sterile 状态在标准模型规范群下是单态,并只能通过与活性中微子的混合来混合。在本文中,我们研究了3+2场景的现象学,结合一个eV尺度的 sterile 中微子和一个亚eV状态,并分析它们对绝对质量相关观测的冲击:中微子质量总和Σ受宇宙学限制约束,来自β衰变的有效电子中微子质量m_β,以及在中微子less双β衰变中探测的有效Majorana质量m_{ββ}。我们证明了两个 sterile 状态的存在可以显著修改允许的参数空间,与三味和3+1框架相比,某些质量顺序方案已被当前宇宙学和实验室限制所排除。最后,我们评估了KATRIN、Project 8和LEGEND-1000的未来灵敏度的影响,突显了亚eV sterile 中微子在探测超出最小三味模型的物理中的互补作用。

英文摘要

The three-flavor framework of neutrino oscillations successfully explains most experimental results, but persistent anomalies at short- and long-baseline experiments hint at the existence of additional light sterile states. In particular, eV-scale sterile neutrinos are motivated by LSND and MiniBooNE results, while sub-eV sterile states with mass-squared differences at the $10^{-2}$ and $10^{-5}$~eV$^2$ scales have been proposed to address the T2K--NO$ν$A tension and the absence of the expected upturn in the solar neutrino energy spectrum, respectively. Such sterile states are singlets under the Standard Model gauge group and mix only through their admixture with active neutrinos. In this work, we investigate the phenomenology of the $3+2$ scenario, incorporating one eV-scale sterile neutrino together with a sub-eV state, and analyze their impact on absolute-mass related observables: the sum of neutrino masses $Σ$ constrained by cosmology, the effective electron neutrino mass $m_β$ from beta decay, and the effective Majorana mass $m_{ββ}$ probed in neutrinoless double beta decay. We demonstrate that the presence of two sterile states can significantly modify the allowed parameter space compared to the three-flavor and $3+1$ frameworks, with some mass-ordering schemes already disfavored by current cosmological and laboratory limits. Finally, we assess the implications of upcoming sensitivities from KATRIN, Project~8, and LEGEND-1000, highlighting the complementary role of sub-eV sterile neutrinos in probing physics beyond the minimal three-flavor paradigm.

2603.16275 2026-06-05 cs.IT math.IT

Rotatable Antenna-Enabled Mobile Edge Computing

可旋转天线赋能的移动边缘计算

Qiyao Wang, Beixiong Zheng, Xue Xiong, Weidong Mei, Changsheng You, Qingqing Wu, Jie Tang

AI总结 本文研究了可旋转天线赋能的移动边缘计算系统,通过联合优化边缘服务器计算资源分配、接收波束成形和所有可旋转天线的偏转角度,以最小化最大计算延迟,从而提升通信可靠性与计算效率。

Comments Submitted to IEEE Wireless Communications Letters on February 5, 2026

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AI中文摘要

在移动边缘计算(MEC)不断演变的背景下,增强通信可靠性与计算效率以支持日益严格低延迟服务仍是一个根本性挑战。可旋转天线(RA)是一种有前景的技术,它引入了新的空间自由度(DoFs)以解决这一挑战。在本文中,我们研究了一个RA赋能的MEC系统,其中天线正视方向可以独立调整,以主动改善对延迟敏感用户的无线信道条件。我们的目标是通过联合优化MEC服务器的计算资源分配、接收波束成形以及所有RA的偏转角度,来最小化最大计算延迟。为了解决由此产生的非凸问题,我们开发了一个高效的交替优化(AO)框架。具体而言,基于Karush-Kuhn-Tucker(KKT)条件推导出最优边缘计算资源分配。给定计算资源后,利用半正定松弛(SDR)结合二分搜索优化接收波束成形。此外,通过分数规划(FP)和连续凸逼近(SCA)优化RA偏转角度。仿真结果验证了所提出的RA赋能MEC方案在减少最大计算延迟方面显著优于传统基准方法。

英文摘要

In the evolving landscape of mobile edge computing (MEC), enhancing communication reliability and computation efficiency to support increasingly stringent low-latency services remains a fundamental challenge. Rotatable antenna (RA) is a promising technology that introduces new spatial degrees of freedom (DoFs) to tackle this challenge. In this letter, we investigate an RA-enabled MEC system where antenna boresight directions can be independently adjusted to proactively improve wireless channel conditions for latency-critical users. We aim to minimize the maximum computation latency by jointly optimizing the MEC server computing resource allocation, receive beamforming, and the deflection angles of all RAs. To address the resulting non-convex problem, we develop an efficient alternating optimization (AO) framework. Specifically, the optimal edge computing resource allocation is derived based on the Karush-Kuhn-Tucker (KKT) conditions. Given the computing resources, the receive beamforming is optimized using semidefinite relaxation (SDR) combined with a bisection search. Furthermore, the RA deflection angles are optimized via fractional programming (FP) and successive convex approximation (SCA). Simulation results verify that the proposed RA-enabled MEC scheme significantly reduces the maximum computation latency compared with conventional benchmark methods.

2509.11381 2026-06-05 math.ST econ.EM stat.ME stat.ML stat.TH

Accuracy Limits of Causal Trees for Individualized Treatment Effects

因果树在个体化治疗效果中的精度极限

Matias D. Cattaneo, Jason M. Klusowski, Ruiqi Rae Yu

AI总结 本文研究了基于自适应递归划分的因果树估计器,推导了其估计精度的下界,指出即使在随机分配的常数效应基准下,标准CART型划分规则构建的因果树在样本空间上的一致误差仍可能以比样本规模的任何幂更慢的速度下降,且样本划分无法消除这一限制。

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AI中文摘要

递归决策树被广泛用于估计实验和观察研究中的异质因果治疗效应。这些方法通常使用CART型递归划分实现,其划分标准旨在识别在协变量定义的子组中治疗效应的变化。我们研究了基于自适应递归划分的因果树估计器,并建立了其估计精度的下界。我们分析的类别包括基于常见治疗效应和平方误差划分标准的版本,有和无样本划分。即使在常数效应基准下,使用标准CART型划分规则构建的因果树的一致误差仍可能比样本规模的任何幂更慢地下降。其根本机制是贪心递归划分选择具有非消失概率的高度不平衡划分,产生包含非常少观测的终端节点,导致估计方差较大。我们进一步表明,样本划分(通常称为“诚实”)无法消除这一限制。因此,因果树估计器可能在协变量空间上以任意慢的速度收敛。同时,这些估计器可以具有小的积分均方误差,表明平均准确性可以掩盖局部不准确性。我们的结果也澄清了现有因果森林及相关集成方法的理论保证中平衡划分假设的作用。

英文摘要

Recursive decision trees are widely used to estimate heterogeneous causal treatment effects in experimental and observational studies. These methods are typically implemented using CART-type recursive partitioning, with splitting criteria designed to identify variation in treatment effects across covariate-defined subgroups. We study causal tree estimators based on adaptive recursive partitioning and establish lower bounds on their estimation accuracy. The class we analyze includes versions with and without sample splitting, based on common treatment effect and squared-error splitting criteria. Even in a constant-effect benchmark with randomized treatment assignment, causal trees constructed via standard CART-type splitting rules can have uniform-norm errors that decrease more slowly than any power of the sample size. The underlying mechanism is that greedy recursive partitioning selects highly imbalanced splits with nonvanishing probability, producing terminal nodes containing very few observations and leading to large estimation variance. We further show that sample splitting, often called ``honesty,'' does not remove this limitation. As a consequence, causal tree estimators may converge arbitrarily slowly uniformly over the covariate space. At the same time, these estimators can have small integrated mean squared error, showing that average accuracy can mask local inaccuracy. Our results also clarify the role of balanced partition assumptions in existing theoretical guarantees for causal forests and related ensemble methods.

2508.19537 2026-06-05 physics.comp-ph

Variational Learning of Physical Intuition from a Few Observations

从少量观测中学习物理直觉的变分学习

Jingruo Peng, Shuze Zhu

AI总结 本文提出了一种变分学习框架,通过少量示例学习从观测参数到最优物理状态的映射,展示了在经典和量子领域,包括强相关分子中的泛化能力,并提出了统一理论解释其泛化机制。

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AI中文摘要

人类常常仅凭少量观测预测物理结果,这种能力称为物理直觉。其背后高效的學習机制尚不明确。本文介绍了一种变分学习框架,其中小神经网络从仅两个或三个相似示例中学习观测参数到最优物理状态的映射。在经典和量子领域,包括强相关分子中,通过这种方式训练的网络能远超训练数据的泛化能力。这种泛化通过统一理论解释:当网络近似一个解流形时,欧拉-拉格朗日算子相对于观测特征是驻定的。该理论预测了临界网络大小以下,稳健泛化无法出现。本文确立了变分学习作为获得人工物理直觉的原理性途径,并提供了理解生物智能中类似能力的理论视角。

英文摘要

Humans often predict physical outcomes from only a few observations, a capability known as physical intuition. The mechanisms underlying this efficient learning remain elusive. Here, we introduce a variational learning framework in which small neural networks learn the mapping from observational parameters to optimal physical states from merely two or three similar examples. Demonstrating across classical and quantum regimes including strongly correlated molecules, networks trained this way generalize far beyond the training data. This generalization is explained by a unified theory: it arises when the network approximates a solution manifold where the Euler-Lagrange operator is stationary with respect to observation features. The theory predicts the existence of a critical network size below which robust generalization fails to emerge. Our work establishes variational learning as a principled route to acquiring artificial physical intuition and offers a theoretical perspective for understanding similar capabilities in biological intelligence.

2506.23213 2026-06-05 math.ST eess.SP stat.TH

Nuisance parameters and elliptically symmetric distributions: a geometric approach to parametric and semiparametric efficiency

干扰参数与椭圆对称分布:一种几何方法用于参数和半参数效率

Stefano Fortunati, Jean-Pierre Delmas, Esa Ollila

AI总结 本文研究了在存在有限维和无限维干扰参数的情况下,参数估计的统计效率之间的深刻且反直觉的联系,通过几何方法提出了一种新的计算投影算子的方法,适用于椭圆分布模型,并扩展到圆和非圆复椭圆对称分布。

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AI中文摘要

椭圆对称分布是半参数模型的经典例子,其中位置向量和散射矩阵(或其参数化)是两个有限维参数,而密度生成器代表一个无限维的干扰项。这种基本的椭圆模型可以通过考虑额外的有限维干扰参数使其更加准确、丰富和灵活。我们的目标是研究在存在有限和无限维干扰参数的情况下,参数估计的统计效率之间的深刻且反直觉的联系。先前的开创性工作通过利用一个一般结果来解决这个问题:如果统计模型具有特定的群不变性,则投影算子可以近似表示为最大不变子σ代数上的条件期望。在本文中,我们表明,对于椭圆分布的统计模型,投影算子可以显式计算,而无需依赖上述近似。这使我们能够获得原始结果,即使在位置向量和散射矩阵由一个有限维向量参数化的情况下,该向量可以分为两个子向量:一个包含感兴趣的参数,另一个包含干扰参数。作为示例,我们展示了如何将所得结果应用于著名的低秩参数化。此外,虽然理论分析将针对实椭圆对称(RES)分布进行开发,但我们将展示如何将我们的结果扩展到圆和非圆复椭圆对称(C-CES和NC-CES)分布的情况。

英文摘要

Elliptically symmetric distributions are a classic example of a semiparametric model where the location vector and the scatter matrix (or a parameterization of them) are the two finite-dimensional parameters of interest, while the density generator represents an \textit{infinite-dimensional nuisance} term. This basic representation of the elliptic model can be made more accurate, rich, and flexible by considering additional \textit{finite-dimensional nuisance} parameters. Our aim is therefore to investigate the deep and counter-intuitive links between statistical efficiency in estimating the parameters of interest in the presence of both finite and infinite-dimensional nuisance parameters. Previous seminal works have addressed this problem by leveraging a general result: if the statistical model has a specific group invariance, then the projection operator onto the semiparametric nuisance tangent space can be asymptotically expressed as a conditional expectation with respect to the maximal invariant sub-$σ$ algebra. In this article, we show that, for the statistical model of elliptical distributions, the projection operator can be explicitly computed without relying on the above-mentioned asymptotic approximation. This allows us to obtain original results also for the case in which the location vector and the scatter matrix are parameterized by a finite-dimensional vector that can be partitioned in two sub-vectors: one containing the parameters of interest and the other containing the nuisance parameters. As an example, we illustrate how the obtained results can be applied to the well-known \virg{low-rank} parameterization. Furthermore, while the theoretical analysis will be developed for Real Elliptically Symmetric (RES) distributions, we show how to extend our results to the case of Circular and Non-Circular Complex Elliptically Symmetric (C-CES and NC-CES) distributions.

2603.11707 2026-06-05 physics.class-ph cond-mat.dis-nn cond-mat.mes-hall physics.optics

Mpemba Effect in Many-Body Systems Near Equilibrium

近平衡态许多体系统中的迈佩尔效应

Philippe Ben-Abdallah

AI总结 本文研究了近平衡态许多体系统中的迈佩尔效应,提出了基于弛豫算子谱几何的统一框架,区分了非均匀迈佩尔效应和严格各向同性迈佩尔效应,并揭示了互易性和非正交性在线性许多体系统异常弛豫中的关键作用。

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AI中文摘要

迈佩尔效应,即初始远离平衡的系统比接近平衡的系统弛豫得更快,已在多种线性和非线性系统中被观测到。本文基于弛豫算子的谱几何,发展了一个统一的框架,用于近平衡态许多体系统中的迈佩尔效应。我们区分了与全局距离到平衡交叉相关的非均匀迈佩尔效应,以及在每个自由度上初始更热的状态仍保持较大但弛豫更快的严格各向同性迈佩尔效应。我们证明互易系统仅允许前者,而互易性破坏使弛豫算子非正交并可能启用后者。这些结果将互易性和非正交性识别为在线性许多体系统异常弛豫中起关键作用的要素。

英文摘要

The Mpemba effect, in which a system initially farther from equilibrium relaxes faster than a closer one, has been observed in a wide variety of linear and nonlinear systems. Here we develop a unified framework for the Mpemba effect in many-body systems near equilibrium based on the spectral geometry of the relaxation operator. We distinguish a non-uniform Mpemba effect, associated with a crossing of global distances to equilibrium, from a strict componentwise Mpemba effect, in which the initially hotter state remains larger in every degree of freedom yet relaxes faster. We show that reciprocal systems admit only the former, whereas reciprocity breaking renders the relaxation operator non-normal and can enable the latter. These results identify reciprocity and non-normality as key ingredients governing anomalous relaxation in linear many-body systems.

2509.01830 2026-06-05 math.LO

A Gentle Introduction to the Axiom of Choice

对选择公理的温和介绍

Andreas Blass, Dhruv Kulshreshtha

AI总结 本文介绍了选择公理,讨论了对其的常见反对意见,并提出了三种接受该公理的理由,同时为非集合论专家提供了较少为人知的结果。

Comments 12 pages

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AI中文摘要

本文为选择公理提供了一次温和的介绍。我们介绍了该公理,讨论了一些常见的反对意见,并提出了三种接受它的理由。尽管本文旨在为集合论非专家提供内容,但我们还包含了一些较少为人知的结果。

英文摘要

This article offers a gentle introduction to the axiom of choice. We introduce the axiom, discuss some common objections to it, and present three kinds of reasons to accept it. Although the exposition is aimed at non-experts in set theory, we also include some lesser-known results.

2603.06486 2026-06-05 cond-mat.mes-hall cond-mat.mtrl-sci

Linearly Polarized Light-Induced Anomalous Hall Effect and Topological Phase Transitions in an Altermagnetic Topological Insulator

线极化光诱导的反常霍尔效应和拓扑相变在交替磁性拓扑绝缘体中

Yichen Liu, Tongshuai Zhu, Haijun Zhang

AI总结 研究通过周期性驱动的线极化光控制交替磁性拓扑绝缘体的反常霍尔效应和拓扑相变,揭示了交替磁体与传统反铁磁体在光照射下的不同响应,并展示了光诱导实现完全自旋极化陈绝缘体的途径。

Comments 10 pages, 4 figures

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AI中文摘要

最近识别的一类列线磁序,其特征是净磁化为零但具有非常规自旋分裂,称为交替磁体(AMs),已引起广泛关注。通过周期性驱动的线极化光(LPL)进行Floquet工程,我们探索了光诱导控制AM拓扑绝缘体的方法。值得注意的是,AMs和传统反铁磁体(AFMs)在LPL照射下表现出不同的响应。具体来说,由于LPL不破坏时间反演(T)对称性或宇称-时间反演(PT)对称性,因此无法在传统AFMs中产生自旋分裂或诱导反常霍尔效应(AHE)。相比之下,AMs本质上缺乏T和PT对称性。它们的自旋上和自旋下能带通过时间反演T和晶格旋转的组合对称性相关联。我们证明LPL可以轻易打破这些对称性,从而在AMs中触发有限的AHE。此外,LPL可以将AM拓扑绝缘体驱动到完全自旋极化的陈绝缘体相。我们的发现不仅提供了一种稳健的实验方案来区分AMs和传统AFMs,还为无耗散自旋电子应用开辟了有前景的途径。

英文摘要

A recently identified class of collinear magnetic order, characterized by vanishing net magnetization yet unconventional spin splitting, known as altermagnets (AMs), has attracted significant research interest. Controlling the unconventional spin splitting and the associated band topology in AMs offers opportunities for realizing novel spin and topological transport phenomena. In this work, using Floquet engineering with periodically driven linearly polarized light (LPL), we explore light-induced control of an AM topological insulator. Remarkably, we find that AMs and conventional antiferromagnets (AFMs) exhibit distinct responses under LPL irradiation. Specifically, since LPL breaks neither time-reversal ($\mathcal{T}$) symmetry nor parity-time-reversal ($\mathcal{PT}$) symmetry, it is incapable of generating spin splitting or inducing an anomalous Hall effect (AHE) in conventional AFMs. In contrast, AMs intrinsically lack both $\mathcal{T}$ and $\mathcal{PT}$ symmetries. Their spin-up and spin-down bands are related by the combined symmetry of time reversal $\mathcal{T}$ and a crystal rotation. We show that LPL readily breaks these symmetries, thereby triggering a finite AHE exclusively in AMs. Furthermore, LPL can drive the AM topological insulator into a fully spin-polarized Chern insulating phase. Our findings not only provide a robust experimental scheme to distinguish AMs from conventional AFMs, but also establish a promising pathway toward dissipationless spintronic applications.

2603.12427 2026-06-05 stat.ME

Variational Bayes and Truncation approximations for Enriched Dirichlet process mixtures

变分贝叶斯与截断近似方法用于增强狄利克雷过程混合模型

Somnath Bhadra, Michael J. Daniels

AI总结 本文提出了一种用于增强狄利克雷过程混合模型(EDPM)的变分贝叶斯估计器,通过改进的截断近似方法提高效率,并展示了其在Nimble中实现阻塞吉布斯采样器的应用,通过模拟和实际数据验证了方法的有效性。

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AI中文摘要

在进行贝叶斯非参数模型推断时,复杂MCMC算法和大数据集的计算时间是一个常见障碍。本文针对增强狄利克雷过程混合模型(EDPM)提出了解决方案。我们基于之前开发的EDPM截断近似方法推导出变分贝叶斯估计器。该估计器可以以两种方式使用:1)开发更高效的截断近似方法;2)作为基于该更高效截断近似方法的阻塞吉布斯采样器或Polya尿 sampler的初始值。我们推导了该更高效截断近似的准确性,并展示了如何通过简单的实现方式在Nimble中实现EDPM的阻塞吉布斯采样器。我们通过模拟验证了近似的有效性,并在实际数据集上进行了说明。

英文摘要

A common impediment in conducting inference for Bayesian nonparametric models is either the need for complex MCMC algorithms and/or computational run-time for large datasets. We propose solutions here for Enriched Dirichlet process mixtures (EDPM). We derive a variational Bayes estimator based on a previously developed truncation approximation for EDPMs. The variational Bayes estimator can be used in two ways: 1) to develop a more efficient truncation approximation; 2) as good initial values for a blocked Gibbs sampler based on this more efficient truncation approximation or for a polya urn sampler. We derive the accuracy of this more efficient truncation approximation and demonstrate how this allows for simple implementation of a blocked Gibbs Sampler EDPMs in Nimble. We confirm the validity of the approximations by simulations and illustrate on a real data set.

2603.09876 2026-06-05 astro-ph.SR

The rotational and magnetic properties of Polaris from long-term spectropolarimetric monitoring

织女星的旋转与磁性性质:长期光谱偏振监测研究

James A. Barron, Gregg A. Wade, Colin P. Folsom

AI总结 通过长期光谱偏振监测研究,确定了织女星的旋转周期和磁性性质,首次直接测量了经典造父变星的旋转周期,并探讨了其磁性场起源与演化历史的挑战。

Comments 20 pages, 13 Figures, 3 Tables. Accepted May 28, 2026 for publication in ApJ after one round of referee comments

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AI中文摘要

织女星是一种高度异常的造父变星,其观测特性难以与恒星演化模型相调和。自2020年首次检测到织女星磁场以来,我们利用加拿大-法国- Hawaii望远镜上的ESPADOnS光谱偏振计进行了磁性监测。我们计算了Stokes V最小二乘反演剖面,并测量了相应的平均纵向磁场强度⟨B_z⟩。在五年的观测中,表面磁场保持 remarkably 稳定,⟨B_z⟩在约-3 G到+0.6 G之间变化。从⟨B_z⟩的周期性调制中,我们推断出恒星的旋转周期为P_rot=100.29±0.19天。这是首次直接测量经典造父变星的旋转周期。先前的干涉仪半径测量和P_rot暗示赤道旋转速度为v_eq=23.3±0.2 km/s。我们设定了保守的投影赤道旋转速度上限v_eq*sin i* <13.5 km/s,并约束了恒星倾角i* <37°。利用之前确定的轨道解,我们发现存在强的自转-轨道偏移。我们确定了恒星自转轴与轨道轴之间倾角的下限为β>18.7°(99%置信度)。我们讨论了在织女星不确定的演化历史和并合假说背景下,解释其表面磁场起源和性质的挑战。

英文摘要

Polaris is a highly unusual Cepheid with observed properties that are difficult to reconcile with stellar evolutionary models. Since the initial detection of Polaris' magnetic field in 2020, we have conducted a magnetic monitoring campaign with the ESPaDOnS spectropolarimeter at the Canada-France-Hawaii Telescope. We compute Stokes $V$ least-squares deconvolution profiles and measure the associated mean longitudinal magnetic field strengths $\langle B_{z}\rangle$. The surface magnetic field has remained remarkably stable over five years of observations, with $\langle B_{z}\rangle$ varying between approximately $-3$ G and $+0.6$ G. From the periodic modulation of $\langle B_{z}\rangle$ we infer a stellar rotation period of $P_{\mathrm{rot}}=100.29\pm0.19$ days. This is the first direct measurement of $P_{\mathrm{rot}}$ for a classical Cepheid. Previous interferometric radius measurements and $P_{\mathrm{rot}}$ imply an equatorial rotation velocity of $v_{\mathrm{eq}}=23.3\pm0.2$ km s$^{-1}$. We set a conservative upper bound on the projected equatorial rotational velocity of $v_{\mathrm{eq}}\sin i_{\star} < 13.5$ km s$^{-1}$ and constrain the stellar inclination angle to be $i_{\star}<37^{\circ}$. Using the previously determined orbital solution, we find a high likelihood of a strong spin-orbit misalignment. We determine the lower bound on the obliquity angle between the stellar rotation and orbital axes to be $β>18.7^{\circ}$ at 99% confidence. We discuss the challenges in interpreting the origin and properties of the surface magnetic field in the context of Polaris' uncertain evolutionary history and the merger hypothesis.

2603.11294 2026-06-05 eess.IV

EquivAnIA: A Spectral Method for Rotation-Equivariant Anisotropic Image Analysis

EquivAnIA:一种用于旋转等变各向异性图像分析的谱方法

Jérémy Scanvic, Nils Laurent

AI总结 本文提出了一种新的谱方法EquivAnIA,利用已建立的方向滤波器(如蛋糕小波和脊滤波器)进行各向异性图像分析,展示了其在旋转下的鲁棒性,并应用于角图像配准任务。

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AI中文摘要

各向异性图像分析在医学和科学成像中普遍存在,尽管该领域的文献广泛,但许多方法对数值旋转的鲁棒性仍需研究。事实上,旋转图像的主要方向和角 profile 通常期望随之旋转。在本文中,我们提出了一种新的谱方法EquivAnIA,用于各向异性图像分析,使用两种已建立的方向滤波器,即蛋糕小波和脊滤波器。我们通过在合成和真实世界图像上进行广泛的实验,展示了其在旋转下的鲁棒性,并成功将其应用于角图像配准任务。代码可在https://github.com/jscanvic/Anisotropic-Analysis获取。

英文摘要

Anisotropic image analysis is ubiquitous in medical and scientific imaging, and while the literature on the subject is extensive, the robustness to numerical rotations of numerous methods remains to be studied. Indeed, the principal directions and angular profile of a rotated image are often expected to rotate accordingly. In this work, we propose a new spectral method for the anisotropic analysis of images (EquivAnIA) using two established directional filters, namely cake wavelets, and ridge filters. We show that it is robust to numerical rotations throughout extensive experiments on synthetic and real-world images containing geometric structures or textures, and we also apply it successfully for a task of angular image registration. The code is available at https://github.com/jscanvic/Anisotropic-Analysis

2603.11247 2026-06-05 physics.comp-ph

Reliable Viscosity Calculation from High-Pressure Equilibrium Molecular Dynamics: Case Study of 2,2,4-Trimethylhexane

从高压平衡分子动力学可靠计算粘度:2,2,4-三甲基己烷的案例研究

Gözdenur Toraman, Dieter Fauconnier, Toon Verstraelen

AI总结 本文提出了一种改进的STACIE算法,用于在高压条件下可靠计算液体润滑剂的粘度,通过引入洛伦兹模型和补充压力张量的非相关偏差压力分量,提高了剪切粘度计算的准确性,并验证了该方法在高压下的可靠性。

Comments major revision after per review

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AI中文摘要

粘度是液体润滑剂的基本性质,但准确确定粘度,尤其是在高压条件下,具有挑战性。尽管平衡分子动力学(EMD)模拟是一种有前途的替代方法,但实际应用中仍存在评估模拟时间充分性和控制格林-库波正式中的不确定性的问题。本文扩展了最近开发的STACIE算法,用于估计输运性质。首先,我们引入洛伦兹模型来估计粘度和指数相关时间,从偏差压力波动的低频功率谱中。其次,我们展示如何补充压力张量的三个传统非对角元素(P_xy,P_yz和P_zx),并加入两个额外的非相关偏差压力分量用于剪切粘度计算。使用这些改进,我们应用STACIE计算2,2,4-三甲基己烷的剪切粘度。我们展示了STACIE在高压条件下可靠计算粘度的能力,提供了一个稳健且自动化的解决方案,具有经过验证的不确定性量化。我们的结果与第十届国际流体性质模拟挑战的结果相比,突显了长EMD模拟的必要性。以前工作的较大偏差主要归因于模拟时间不足和任意的后处理选择,而不是力场限制。与以前的研究不同,我们的粘度估计与实验结果一致(相对误差<6%)直到最高压力1 GPa,突显了STACIE系统方法在粘度预测中的改进可靠性和准确性。

英文摘要

Viscosity is a fundamental property of liquid lubricants, yet it is challenging to determine accurately, especially at high pressures. Although equilibrium molecular dynamics (EMD) simulations are a promising alternative to resource-intensive experiments, practical challenges remain in assessing the sufficiency of simulation time and in controlling uncertainties in the Green-Kubo formalism due to the finite amount of trajectory data. In this work, we extend the STable AutoCorrelation Integral Estimator (STACIE), a recently developed algorithm for estimating transport properties. First, we introduce the Lorentz model to estimate the viscosity and the exponential correlation time from the low-frequency power spectrum of deviatoric pressure fluctuations. Second, we show how to supplement the three conventional off-diagonal elements of the pressure tensor ($P_{xy}$, $P_{yz}$ and $P_{zx}$) with two additional uncorrelated deviatoric pressure components for shear viscosity calculations. Using these improvements, we apply STACIE to calculate the shear viscosity of 2,2,4-trimethylhexane from EMD simulations. We demonstrate STACIE's capability to reliably calculate viscosity under high-pressure conditions, offering a robust and automated solution with validated uncertainty quantification. Our results, when compared to the outcomes of the 10th International Fluid Properties Simulation Challenge, underscore the need for long EMD simulations. Large deviations from experimental viscosities in previous works were primarily due to insufficient simulation times and ad hoc post-processing choices, rather than the limitations of the force fields used. Unlike previous studies, our viscosity estimates agree well with experimental results (relative error < 6%) up to the highest pressure of 1 GPa, highlighting the improved reliability and accuracy of STACIE's systematic approach to viscosity predictions.

2603.10513 2026-06-05 math.CV

On Geometric properties and Coefficient bounds for $\mathcal{S}^*_{B}$

关于$\mathcal{S}^*_{B}$类函数的几何性质和系数界

S. Sivaprasad Kumar, Arya Tripathi

AI总结 本文研究了属于由气球形域关联的$\mathcal{S}^*_{B}$类函数的几何性质,并推导了Zalcman函数、Kruskal不等式、第三阶Hankel、Toeplitz和Hermitian-Toeplitz行列式的精确界,通过构造合适的极值函数验证了结果的最优性。

Comments We modified the earlier version by including geometric properties of the Ma-Minda function and zalkman function & Kruskal inequality bounds. Changed title and abstract accordingly

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AI中文摘要

本文研究了属于由气球形域关联的$\mathcal{S}^*_{B}$类函数的几何性质,并推导了Zalcman函数、Kruskal不等式、第三阶Hankel、Toeplitz和Hermitian-Toeplitz行列式的精确界。通过构造合适的极值函数验证了这些结果的最优性。

英文摘要

This paper deals with the geometric properties of functions belonging to the class $\mathcal{S}^*_{B}$ of starlike functions associated with a balloon-shaped domain, given by \[ \mathcal{S}^{\ast}_{B}= \left\{ f \in \mathcal{A} : \frac{z f'(z)}{f(z)} \prec \frac{1}{1-\log (1+z)} :=B(z), \quad z \in \mathbb{D} \right\}, \] and also derive sharp bounds for the Zalcman functionals, Krushkal inequality, third-order Hankel, Toeplitz and Hermitian-Toeplitz determinant. The sharpness of these results are verified by constructing suitable extremal functions.

2603.10275 2026-06-05 eess.SY cs.SY math.OC

Optimal Control Synthesis of Closed-Loop Recommendation Systems over Social Networks

社交网络闭环推荐系统最优控制合成

Simone Mariano, Paolo Frasca

AI总结 本文从控制论角度研究社交网络和电商平台的推荐系统设计问题,将推荐系统设计视为具有性能指标的无限时间状态反馈最优控制问题,通过奖励一致性与参与度、惩罚极化和偏离基线、正则化邻近用户曝光来实现稳定推荐系统。

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AI中文摘要

本文从控制论角度研究社交网络和电商平台的推荐系统设计问题。我们将推荐系统的设计视为一个具有性能指标的无限时间状态反馈最优控制问题,该性能指标(i)奖励一致性与参与度,(ii)惩罚极化和偏离未控制基线的大偏差,(iii)正则化邻近用户之间的曝光。推荐内容被提供给平台用户,这些用户被假设为遵循网络化、多主题、连续时间意见动态。我们证明在简单的代数谱条件下,设计的控制能产生稳定的推荐系统。相反,当在最优控制问题中选择不恰当的权重(即过度奖励参与度)时,闭环系统可能会表现出破坏性的病态行为,与设计目标相冲突。

英文摘要

This paper addresses the problem of designing recommendation systems for social networks and e-commerce platforms from a control-theoretic perspective. We treat the design of recommendation systems as a state-feedback infinite-horizon optimal control problem with a performance index that (i) rewards alignment and engagement, (ii) penalizes polarization and large deviations from an uncontrolled baseline, and (iii) regularizes exposure across neighboring users. The recommendation entries are fed to the platform users, who are assumed to follow a networked, multi-topic, continuous-time opinion dynamics. We show that the designed control yields a stabilizing recommendation system under simple algebraic spectral conditions on the weights that encode the platform's preference for engagement, stability of preferences, polarization, and cross-user diversity. Conversely, we show that when ill-posed weights are selected in the optimal control problem (namely, when engagement is excessively rewarded), the closed-loop system can exhibit destabilizing, pathological behaviors that conflict with the design objectives.

2412.10412 2026-06-05 cond-mat.stat-mech

Exact solution of the three-dimensional (3D) Z2 lattice gauge theory

三维Z2晶格规范理论的精确解

Zhidong Zhang

AI总结 本文通过研究三维伊辛模型和Z2晶格规范模型之间的对偶性,推导出三维Z2晶格规范理论的精确解,并探讨了非局域效应的起源以及非平凡拓扑结构对物理性质的影响。

Comments 52 pages, 5 figures, corrections are made on Eq. (9)

Journal ref Open Physics 23 (2025) 20250215

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AI中文摘要

在本文中,详细研究了三维伊辛模型和Z2晶格规范模型中非局域效应的起源以及非平凡拓扑结构对物理性质的贡献。然后通过这两个模型之间的对偶性推导出三维Z2晶格规范理论的精确解。对这些多体相互作用自旋系统进行了多方面的研究,包括维度性、对偶性、对称性、流形、退化态等。还评估了这些系统与超流体、超导体等的联系。此外,讨论了三维Z2晶格规范理论在拓扑、几何和代数方面的物理意义和数学方面。

英文摘要

In this work, the origin of nonlocal effects is inspected and the contributions of nontrivial topological structures to physical properties are investigated in details for both the 3D Ising model and the Z2 lattice gauge model. Then the exact solution for the 3D Z2 lattice gauge theory is derived by the duality between the two models. Several fundamental issues, such as dimensionality, duality, symmetry, manifold, degenerate states, are investigated for these many-body interacting spin systems. The connections with superfluid, superconductors, etc. are evaluated. Furthermore, physical significances and mathematical aspects of the 3D Z2 lattice gauge theory are discussed with respect to topology, geometry, and algebra.

2603.09658 2026-06-05 physics.flu-dyn

Immiscible two-phase flow in porous media: a statistical mechanics approach

多相流在多孔介质中的不混溶性:一种统计力学方法

Alex Hansen, Santanu Sinha

AI总结 本文提出了一种基于统计力学的多孔介质中不混溶性多相流的描述方法,通过引入新的变量和热力学形式化,解决了多孔介质中多相流的尺度扩大问题。

Comments 14 pages, 4 figures

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AI中文摘要

在多孔介质中不混溶性多相流的物理学中,核心问题在于找到一个适当的描述方法,以足够大的尺度将介质视为连续体:尺度扩大问题。迄今为止,唯一可行的多相流尺度扩大问题的方法是一组现象学方程,但它们显然存在弱点。试图超越这一相对渗透率理论的尝试由于复杂性爆炸而未能带来实际应用。Edwin T. Jaynes在五十年代提出了一种基于Shannon信息理论熵的非热系统的统计力学一般化方法。该方法被用来构建多孔介质中不混溶性多相流在连续尺度上的描述,这与孔隙尺度的物理直接相关,并且在可管理的复杂性水平上。该方法导致在连续尺度上具有所有变量之间关系的类似热力学形式化。新出现的变量出现。其中,共动速度突出显示为一个关键变量,对普通热力学有影响。本文简要回顾了这一方法。

英文摘要

The central problem in the physics of immiscible two-phase flow in porous media is to find a proper description of the flow at scales large enough so that the medium may be regarded as a continuum: the scale-up problem. So far, the only workable approach to the multiphase flow scale-up problem has been a set of phenomenological equations that have obvious weaknesses. Attempts at going beyond this relative permeability theory have so far not led to practical applications due to exploding complexity. Edwin T. Jaynes proposed in the fifties a generalization of statistical mechanics to non-thermal systems based on the information theoretical entropy of Shannon. This approach is used to construct a description of immiscible two-phase flow in porous media at the continuum scales, which is directly related to the physics at the pore scale, and at a level of complexity that is manageable. The approach leads to a thermodynamics-like formalism at the continuum scale with all the relations between variables that "normal" thermodynamics has to offer. New emergent variables appear. Among these, the co-moving velocity stands out as a key variable with implications for ordinary thermodynamics. We present here a short review of this approach.

2602.16151 2026-06-05 cs.CY

Queer NLP: A Critical Survey on Literature Gaps, Biases and Trends

Queer NLP: 对文献空白、偏见和趋势的批判性调研

Sabine Weber, Angelina Wang, Ankush Gupta, Arjun Subramonian, Dennis Ulmer, Eshaan Tanwar, Geetanjali Aich, Hannah Devinney, Jacob Hobbs, Jennifer Mickel, Joshua Tint, Mae Sosto, Ray Groshan, Simone Astarita, Vagrant Gautam, Verena Blaschke, William Agnew, Wilson Y Lee, Yanan Long

AI总结 本文通过分析LGBTQIA+社区与NLP技术关系的研究论文,揭示了当前研究趋势、存在的空白以及未来研究方向,强调了对边缘群体的公平性和包容性的重要性。

Comments 25 pages, 3 figures

详情
AI中文摘要

自然语言处理(NLP)技术正迅速改变人类创造、处理和解读语言的方式。随着NLP在招聘、法律、医疗等领域中的应用,理解并减轻对边缘群体的负面影响至关重要。本文调研了截至2026年2月ACL Anthology上所有明确讨论LGBTQIA+社区与NLP技术关系的论文(共122篇),以回答以下研究问题:(1)当前的研究趋势是什么?(2)在主题和方法上存在哪些空白?(3)哪些领域可以为未来研究提供机会?研究发现,尽管近年来关于queer NLP的论文数量有所增长,但大多数论文采取的是反应性而非前瞻性的方法,关注现有系统的不足而非创造新解决方案。本文揭示了许多未来研究的机会,特别是关于利益相关者的参与、交叉性、跨学科性和非英语语言。此外,本文还从酷儿研究的角度出发,强调了NLP论文中未被研究的主题和盲点。除了作为已做工作的路线图,本文也是呼吁朝着更加公正和包容的NLP技术方向努力的呼吁。

英文摘要

Natural language processing (NLP) technologies are rapidly reshaping how language is created, processed, and interpreted by humans. With current and potential applications in hiring, law, healthcare, and other areas that impact people's lives, understanding and mitigating harms towards marginalized groups is critical. In this survey, we examine NLP research papers that explicitly address the relationship between LGBTQIA+ communities and NLP technologies. We systematically review all such papers published in the ACL Anthology up until February 2026 (n=122), to answer the following research questions: (1) What are current research trends? (2) What gaps exist in terms of topics and methods? (3) What areas are open for future work? We find that while the number of papers on queer NLP has grown within the last few years, most papers take a reactive rather than a proactive approach, focusing on shortcomings of existing systems rather than creating new solutions. Our survey uncovers many opportunities for future work, especially regarding stakeholder involvement, intersectionality, interdisciplinarity, and languages other than English. We also offer an outlook from a queer studies perspective, highlighting understudied topics and blind spots in the harms addressed in NLP papers. Beyond being a roadmap of what has been done, this survey is a call to action for work towards more just and inclusive NLP technologies.