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2512.12580 2026-06-11 cs.CR eess.SP hep-th math-ph math.MP math.RA 版本更新

Cryptographic transformations over polyadic rings

基于多元环的密码学变换

Steven Duplij, Qiang Guo, Na Fu

AI总结 提出基于多元环的密码学范式,利用参数到元数的映射Φ(a,b)构建非单射、非满射且多值的复杂关系,设计两种加密过程,通过多元量化模拟信号传输信息,增强安全性。

Comments 21 pages, revtex 4.2

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AI中文摘要

本文介绍了一种基于非派生多元代数结构的新型密码学范式。传统密码系统依赖于群、环或域内的二元运算,其良好理解的特性可被密码分析利用。为克服这些漏洞,我们提出转向多元环,它通过允许更高元数的运算来推广经典环:一个$m$元加法和一个$n$元乘法。我们方法的基础是多元整数的构造——普通整数的同余类,赋予这样的$m$元和$n$元运算。一个关键创新是参数到元数的映射$\Phi(a,b)=(m,n)$,它将定义同余类的参数$(a,b)$与代数闭包所需的特定元数联系起来。该映射在数学上是复杂的:它是非单射、非满射且多值的。这种复杂、非唯一的关系构成了所提密码系统安全性的核心。我们提出了两种具体的加密过程,利用这种结构,将明文编码在多元环的参数中,并通过多元量化的模拟信号传输信息。在一种方法中,明文与加法元数$m_{i}$相关联,并通过此类信号的求和来保护;在另一种方法中,明文与环参数$a_{i}$相关联,并通过它们的乘法来保护。在这两种情况下,多元运算的“量化”性质生成方程组,对于拥有正确密钥的合法接收者来说直接明了,但对于没有密钥的攻击者来说极其困难。由此产生的框架有望大幅提高密码安全性。这项工作为这类新型加密方案奠定了理论基础,并突显了它们在构建鲁棒的下一代密码协议方面的潜力。

英文摘要

This article introduces a novel cryptographic paradigm based on nonderived polyadic algebraic structures. Traditional cryptosystems rely on binary operations within groups, rings, or fields, whose well-understood properties can be exploited in cryptanalysis. To overcome these vulnerabilities, we propose a shift to polyadic rings, which generalize classical rings by allowing operations of higher arity: an $m$-ary addition and an $n$-ary multiplication. The foundation of our approach is the construction of polyadic integers -- congruence classes of ordinary integers endowed with such $m$-ary and $n$-ary operations. A key innovation is the parameter-to-arity mapping $Φ(a,b)=(m,n)$, which links the parameters $(a,b)$ defining a congruence class to the specific arities required for algebraic closure. This mapping is mathematically intricate: it is non-injective, non-surjective, and multivalued. This complex, non-unique relationship forms the core of the proposed cryptosystem's security. We present two concrete encryption procedures that leverage this structure by encoding plaintext within the parameters of polyadic rings and transmitting information via polyadically quantized analog signals. In one method, plaintext is linked to the additive arity $m_{i}$ and secured using the summation of such signals; in the other, it is linked to a ring parameter $a_{i}$ and secured using their multiplication. In both cases, the "quantized" nature of polyadic operations generates systems of equations that are straightforward for a legitimate recipient with the correct key but exceptionally difficult for an attacker without it. The resulting framework promises a substantial increase in cryptographic security. This work establishes the theoretical foundation for this new class of encryption schemes and highlights their potential for constructing robust, next-generation cryptographic protocols.

2512.12269 2026-06-11 hep-th math-ph math.DG math.MP 版本更新

Modular Classes and Supersymmetric Berezin Volumes

模类与超对称Berezin体积

Andrew James Bruce

AI总结 本文提出Q-流形的模类为N=2 d=1超平移代数的超几何表示论中超对称Berezin体积的存在性提供了有效方法,并建立了Berezin体积在两种超荷下不变的上同调一致性判据。

Comments short note, 5 pages

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AI中文摘要

我们认为Q-流形的模类为$\mathcal{N}=2$ $d=1$超平移代数的超几何表示论中处理超对称Berezin体积的存在性提供了有效方法。我们建立了Berezin体积在两种超荷下不变的上同调一致性判据。

英文摘要

We argue that modular classes of Q-manifolds provide an efficient method for addressing the existence of supersymmetric Berezin volumes in the supergeometric representation theory of the $\mathcal{N}=2$ $d=1$ supertranslation algebra. We establish a cohomological coherence criterion for the existence of a Berezin volume that is invariant under both of the supercharges.

2512.11970 2026-06-11 hep-th cond-mat.str-el hep-ph 版本更新

Anomalies on ALE spaces and phases of gauge theory

ALE空间上的反常与规范理论的相

Mohamed M. Anber

AI总结 通过在Eguchi-Hanson空间上放置量子场论,利用其非平凡第二上同调和带挠的渐近边界,揭示了标准闭四维流形上无法探测的't Hooft反常,并对渐近自由规范理论施加额外约束。

Comments 55 pages+appendices, 1 figure, the analysis of fermion zero modes appeared previously in arXiv:2509.22788; references added, typos corrected, new section 4.3 and new appendix E added, matches the published version

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AI中文摘要

我们展示了某些't Hooft反常,在标准闭四维探针上无法被探测到,但当量子场论被放置在渐近局部欧几里得(ALE)空间上时,这些反常变得可见。作为一个具体例子,我们使用Eguchi-Hanson(EH)空间,其定义特征是由自交二维球面生成的非平凡第二上同调,以及其渐近边界$\mathbb{RP}^3$,该边界带有挠,从而提供了传统背景上缺失的额外上同调数据。对于一个具有对称性$G_1\times G_2$的理论,我们为$G_1$开启背景通量,并通过执行全局$G_2$变换来探测潜在的反常;由此产生的反常由五维映射环面捕获。该反常接收来自EH空间上的四维示性类以及来自与$\mathbb{RP}^3$边界相关的$\eta$-不变量的贡献。以这种方式探测到的反常对具有固定平凡渐近边界条件的渐近自由规范理论施加了额外约束。特别是,在标准闭流形上匹配反常的红外复合谱可能仍然无法重现EH反常,因此不能单独提供一个完整的对称性保持的红外实现。

英文摘要

We show that certain 't Hooft anomalies not detected by standard closed four-dimensional probes can become visible when a quantum field theory is placed on asymptotically locally Euclidean (ALE) spaces. As a concrete example, we use the Eguchi-Hanson (EH) space, whose defining features are its nontrivial second cohomology generated by the self-intersecting two-sphere and its asymptotic boundary $\mathbb{RP}^3$, which carries torsion and thus furnishes additional cohomological data absent on conventional backgrounds. For a theory with symmetry $G_1\times G_2$, we turn on background flux for $G_1$ and probe potential anomalies by performing a global $G_2$ transformation; the resulting anomaly is captured by a five-dimensional mapping torus. The anomaly receives contributions from the four-dimensional characteristic classes on EH space as well as from the $η$-invariant associated with the $\mathbb{RP}^3$ boundary. The anomaly detected in this way imposes additional constraints on asymptotically free gauge theories with fixed trivial asymptotic boundary conditions. In particular, infrared composite spectra that match anomalies on standard closed manifolds may nevertheless fail to reproduce the EH anomaly, and thus cannot by themselves furnish a complete symmetry-preserving infrared realization.

2305.04908 2026-06-11 quant-ph cs.CC 版本更新

Tight Bounds for Quantum Phase Estimation and Related Problems

量子相位估计及相关问题的紧界

Nikhil S. Mande, Ronald de Wolf

AI总结 针对量子相位估计及其变体,在给定不同辅助信息(如本征态、重叠度γ)下,刻画算法代价的紧界,并证明误差概率降低的代价下界为Ω(1/δ log(1/ε))。

Comments Version 3: Journal (Quantum) version

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AI中文摘要

相位估计,由 Kitaev [arXiv'95] 提出,是量子计算中最基本的子程序之一。在基本场景中,给定对酉算子 $U$ 的黑盒访问,以及 $U$ 的一个本征态 $\lvert \psi \rangle$,其未知本征值为 $e^{i\theta}$,任务是以高概率估计本征相位 $\theta$ 在 $\pm\delta$ 范围内。对我们而言,算法的代价是 $U$ 和 $U^{-1}$ 的应用次数。我们严格刻画了相位估计的几个变体的代价,在这些变体中,我们不再被给予本征态,而是需要估计 $U$ 的最大本征相位,并辅以状态(或制备这些状态的酉算子)形式的建议,这些状态被承诺与最大本征空间至少有某个重叠 $\gamma$。我们给出了所有参数范围内的算法和几乎匹配的下界。我们表明,少量副本的建议状态(或制备建议的酉算子)并不比没有建议好多少。我们还表明,大量建议(应用制备建议的酉算子)并不会显著降低代价,了解 $U$ 的本征基也不会。我们立即得到了酉递归时间问题复杂性的下界,解决了 She 和 Yuen [ITCS'23] 的一个开放问题。最后,我们研究了在基本相位估计场景中如何有效地降低错误概率。我们表明,精度为 $\delta$、错误概率为 $\epsilon$ 的相位估计算法具有代价 $\Omega\left(\frac{1}{\delta}\log\frac{1}{\epsilon}\right)$,与一个简单的上界匹配。这与量子计算中的其他一些场景(例如搜索)形成对比,在这些场景中,错误概率降低仅需因子 $O(\sqrt{\log(1/\epsilon)})$。我们的下界使用了带三角多项式的多项式方法的一个变体。

英文摘要

Phase estimation, due to Kitaev [arXiv'95], is one of the most fundamental subroutines in quantum computing. In the basic scenario, one is given black-box access to a unitary $U$, and an eigenstate $\lvert ψ\rangle$ of $U$ with unknown eigenvalue $e^{iθ}$, and the task is to estimate the eigenphase $θ$ within $\pmδ$, with high probability. The cost of an algorithm for us is the number of applications of $U$ and $U^{-1}$. We tightly characterize the cost of several variants of phase estimation where we are no longer given an eigenstate, but are required to estimate the maximum eigenphase of $U$, aided by advice in the form of states (or a unitary preparing those states) which are promised to have at least a certain overlap $γ$ with the top eigenspace. We give algorithms and nearly matching lower bounds for all ranges of parameters. We show that a small number of copies of the advice state (or of an advice-preparing unitary) are not significantly better than having no advice at all. We also show that having lots of advice (applications of the advice-preparing unitary) does not significantly reduce cost, and neither does knowledge of the eigenbasis of $U$. We immediately obtain a lower bound on the complexity of the Unitary recurrence time problem, resolving an open question of She and Yuen~[ITCS'23]. Lastly, we study how efficiently one can reduce the error probability in the basic phase-estimation scenario. We show that a phase-estimation algorithm with precision $δ$ and error probability $ε$ has cost $Ω\left(\frac{1}δ\log\frac{1}ε\right)$, matching an easy upper bound. This contrasts with some other scenarios in quantum computing (e.g., search) where error-probability reduction costs only a factor $O(\sqrt{\log(1/ε)})$. Our lower bound uses a variant of the polynomial method with trigonometric polynomials.

2512.08515 2026-06-11 hep-ph hep-ex 版本更新

Reviving $Z^\prime$ Portal Dark Matter with Conversion Mechanism

复兴$Z^\prime$门户暗物质与转换机制

Zhen-Wei Wang, Zhi-Long Han, Fei Huang, Honglei Li, Ang Liu

AI总结 本文基于$U(1)_{B-L}$规范对称性提出新基准模型,通过引入狄拉克暗费米子及其重伙伴,利用压缩质量谱中的转换机制产生暗物质遗迹密度,在共振和隔离场景下满足当前对撞机、直接探测和宇宙学约束。

Comments 34 pages, 10 figures

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Journal ref
Phys.Rev.D 113 (2026) 11, 115016
AI中文摘要

在许多具有扩展规范对称性的新物理模型中,新规范玻色子$Z'$可以介导暗物质与标准模型粒子之间的相互作用。对于传统的$Z^\prime$门户暗物质,对撞机和直接探测约束通常构成重大挑战。为了解决这一紧迫问题,我们在本文中提出了一个基于规范$U(1)_{B-L}$对称性的新基准模型,该模型引入了一个狄拉克暗费米子$\tilde{\chi}_1$和一个更重的伙伴$\tilde{\chi}_2$,它们分别具有零和非零的$U(1)_{B-L}$电荷。包括质量项$\delta m \bar{\tilde{\chi}}_1\tilde{\chi}_2$导致质量本征态下的暗费米子$\chi_1$和$\chi_2$,其中较轻的$\chi_1$被视为暗物质候选者。在压缩质量谱$m_{\chi_1}\simeq m_{\chi_2}$下,出现了各种有趣的过程来产生遗迹密度,例如共散射$\chi_2f\to\chi_1f$、转换$\chi_2\chi_i\to\chi_1\chi_j$和共湮灭$\chi_1\chi_2\to f\bar{f}$过程。由于暗费米子之间的混合角$\theta$很小,暗物质$\chi_1$与规范玻色子$Z'$的有效规范耦合很小,这是该模型的一个显著特征,使得许多方面的现象学更有前景。在本文中,我们研究了在共振和隔离场景框架内通过新机制产生暗物质的过程。还考虑了对撞机、暗物质和宇宙学现象学约束的影响。我们报告说,在当前约束下,转换机制在共振和隔离场景中都受到青睐。

英文摘要

In many new physics models with extended gauge symmetry, the new gauge boson $Z'$ could mediate the interactions between the dark matter and standard model particles. For the conventional $Z^\prime$ portal dark matter, the collider and the direct detection constraints typically pose a significant challenge. To address this pressing issue, we present in this paper a new benchmark model based on the gauged $U(1)_{B-L}$ symmetry, which introduces a Dirac dark fermion $\tildeχ_1$ and a heavier partner $\tildeχ_2$ with zero and nonzero $U(1)_{B-L}$ charge, respectively. Including the mass term $δm \bar{\tildeχ}_1\tildeχ_2$ results in the dark fermions $χ_1$ and $χ_2$ in the mass eigenstate, where the lighter one $χ_1$ is regarded as the dark matter candidate. Various intriguing processes for the relic density arise with the compressed mass spectrum $m_{χ_1}\simeq m_{χ_2}$, such as the coscattering $χ_2f\toχ_1f$, the conversion $χ_2χ_i\toχ_1χ_j$, and the coannihilation $χ_1χ_2\to f\bar{f}$ processes. Suppressed by the small mixing angle $θ$ between the dark fermions, the small effective gauge coupling of dark matter $χ_1$ to the gauge boson $Z'$ is one distinct feature of this model, rendering phenomenology in many aspects more promising. In this paper, we investigate the production of dark matter through new mechanisms within the frameworks of resonance and secluded scenarios. The impacts of phenomenological constraints from collider, dark matter, and cosmology are also taken into account. We report that the conversion mechanism is both favored by the resonance and secluded scenarios under current constraints.

2512.06319 2026-06-11 astro-ph.CO 版本更新

A Fully Photometric Approach to Type Ia Supernova Cosmology in the LSST Era: Host Galaxy Redshifts and Supernova Classification

LSST时代Ia型超新星宇宙学的全测光方法:宿主星系红移与超新星分类

Ayan Mitra, Richard Kessler, Rebecca C. Chen, Alex Gagliano, Matthew Grayling, Surhud More, Gautham Narayan, Helen Qu, Srinivasan Raghunathan, Alex I. Malz, Michelle Lochner, The LSST Dark Energy Science Collaboration

AI总结 针对LSST时代大量缺乏光谱分类和红移的Ia型超新星,提出基于测光分类和宿主星系测光红移的宇宙学分析方法,通过模拟实现约150的优值,显著优于DESVYR。

Comments Accepted in ApJ. 19 pages, 13 figures

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AI中文摘要

即将到来的Vera C. Rubin天文台时空遗产巡天(LSST)预计将发现近百万颗Ia型超新星(SNeIa),为约束暗能量提供前所未有的机会。这些事件中的绝大多数将缺乏光谱分类和红移,因此需要完全基于测光的方法来最大化宇宙学约束能力。我们基于扩展的LSST天文时间序列分类挑战(ELAsTiCC)进行了详细模拟,并利用测光分类的SNeIa结合宿主星系测光红移进行了宇宙学分析。该数据集具有真实的多波段光变曲线、非SNIa污染、宿主错误关联以及高红移深钻场(DDF)(约50平方度)中的瞬变-宿主相关性。我们还包含了一个基于宽快深(WFD)场的光谱确认的低红移样本。我们采用联合SN+宿主测光红移拟合、基于神经网络的测光分类器(SCONE)以及带偏差校正的BEAMS(BBC)方法,构建了偏差校正的哈勃图。我们生成了统计+系统协方差矩阵,并利用宇宙微波背景约束的先验进行宇宙学拟合。我们拟合并展示了wCDM暗能量模型以及更一般的Chevallier-Polarski-Linder(CPL)w0wa模型的结果。使用约6000个事件的模拟样本,我们实现了约150的优值(FoM),显著大于DESVYR的54 FoM。对25个独立样本的平均分析结果,我们发现存在小但显著的偏差,表明需要进一步的分析测试和开发。

英文摘要

The upcoming Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) is expected to discover nearly a million Type Ia supernovae (SNeIa), offering an unprecedented opportunity to constrain dark energy. The vast majority of these events will lack spectroscopic classification and redshifts, necessitating a fully photometric approach to maximize cosmology constraining power. We present detailed simulations based on the Extended LSST Astronomical Time Series Classification Challenge (ELAsTiCC), and a cosmological analysis using photometrically classified SNeIa with host galaxy photometric redshifts. This dataset features realistic multi-band light curves, non-SNIa contamination, host mis-associations, and transient-host correlations across the high-redshift Deep Drilling Fields (DDF) (~ 50 deg^2). We also include a spectroscopically confirmed low-redshift sample based on the Wide Fast Deep (WFD) fields. We employ a joint SN+host photometric redshift fit, a neural network based photometric classifier (SCONE), and BEAMS with Bias Corrections (BBC) methodology to construct a bias-corrected Hubble diagram. We produce statistical + systematic covariance matrices, and perform cosmology fitting with a prior using Cosmic Microwave Background constraints. We fit and present results for the wCDM dark energy model, and the more general Chevallier-Polarski-Linder (CPL) w0wa model. With a simulated sample of ~6000 events, we achieve a Figure of Merit (FoM) value of about 150, which is significantly larger than the DESVYR FoM of 54. Averaging analysis results over 25 independent samples, we find small but significant biases indicating a need for further analysis testing and development.

2512.05330 2026-06-11 astro-ph.EP astro-ph.IM 版本更新

On-Orbit Calibration of Danuri/PolCam. I. Geometric Calibration

Danuri/PolCam在轨标定. I. 几何标定

Kilho Baek, Sungsoo S. Kim, Minsup Jeong, Young-Jun Choi

AI总结 针对Danuri号月球轨道器PolCam的倾斜观测几何,利用160,256个连接点与Kaguya MI地图匹配,通过优化观测时间和相机模型实现高精度几何标定,生成正射影像。

Comments 13 pages, 9 figure, 2 tables, published in JKAS

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Journal ref
J. Korean Astron. Soc., 58, (2025), 291-303
AI中文摘要

韩国首个月球轨道器Danuri搭载的宽视场偏振相机(PolCam)是一项开创性仪器,旨在对月球进行首次全球偏振和高相位角观测。精确的几何标定对于该任务至关重要,尤其是由于PolCam高度倾斜的观测几何引入了显著的地形畸变。我们提出了一种全面的在轨几何标定方法,该方法依赖于从PolCam图像与经过良好正射校正的Kaguya多波段成像仪(MI)全球地图之间的特征匹配中提取的160,256个连接点。该数据集使我们能够解决两个基本挑战:(1)通过简单的线性模型精确重建观测条带每一行的观测时间,以及(2)精化精确的相机模型,即PolCam光学的几何模型。我们针对这两个挑战的优化方法将识别特征的二维图像坐标转换为三维月球坐标,并最小化相对于Kaguya MI地图提供的参考坐标的重投影误差。根据精化后的观测时间和相机模型,我们计算观测图像每个像素的精确经度、纬度和高程。然后利用这些估计的三维坐标生成正射影像,这是几何标定的最终产品。所得标定达到了与先前月球轨道器相当的几何精度,并为生成PolCam的几何校正数据产品建立了基础框架。

英文摘要

The wide-angle Polarimetric Camera (PolCam) onboard South Korea's first lunar orbiter, Danuri, is a pioneering instrument designed to conduct the first global polarimetric and high-phase-angle survey of the Moon. Precise geometric calibration is critical for this mission, particularly due to PolCam's highly oblique viewing geometry, which introduces significant topographic distortion. We present a comprehensive on-orbit geometric calibration that relies on 160,256 tie points derived from matching features between PolCam images and the well-orthorectified global map of the Kaguya Multiband Imager (MI). This dataset allows us to address two fundamental challenges: (1) the accurate reconstruction of the observation time for each line of an observation strip via a simple linear model, and (2) the refinement of the precise camera model, geometric model for PolCam optics. Our optimization method for these two challenges transforms the 2D image coordinates of identified features into 3D lunar coordinates and minimizes the reprojection error against the reference coordinates provided by the Kaguya MI map. From the refined observation time and camera model, we compute the precise longitude, latitude, and elevation of each pixel of an observed image. These estimated 3D coordinates are then used to generate orthorectified images, the final product of the geometric calibration. The resulting calibration achieves a geometric precision comparable to that of previous lunar orbiters and establishes the foundational framework necessary to produce geometrically-corrected data products of PolCam.

2512.04168 2026-06-11 hep-ph astro-ph.CO 版本更新

Electroweak phase transition in SMEFT: Gravitational wave and collider complementarity

SMEFT中的电弱相变:引力波与对撞机互补性

Sahabub Jahedi, Indrajit Saha, Abhik Sarkar

AI总结 研究标准模型有效场论中维度-6算子诱导的一阶电弱相变,通过双希格斯产生和引力波探测的互补性来探索新物理。

Comments v2:34 pages, 13 figures, 4 tables; cut-based analysis added and compared with ANN; improved discussions; accepted for publication in JHEP

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AI中文摘要

我们在标准模型有效场论(SMEFT)框架内研究由维度-6算子诱导的一阶电弱相变(FO-EWPT)。此类现象可以通过对撞机实验中的双希格斯产生以及引力波(GW)探测独立地进行探测。有三个(一个)维度-6 SMEFT算子同时在树(1-圈)水平上修改希格斯势,并对强子对撞机上的双希格斯产生有贡献。由于在当前LHC运行中双希格斯产生受到抑制,我们旨在在LHC的高亮度(HL)和高能量(HE)运行中探测这一产生过程,以实现对维度-6 SMEFT算子的更好灵敏度。在探测FO-EWPT的背景下分析了这些算子之间的相关性,强调了未来GW观测与升级LHC搜索之间的互补性。

英文摘要

We study the first-order electroweak phase transition (FO-EWPT) within the Standard Model Effective Field Theory (SMEFT) framework induced by dimension-6 operators. Such phenomena can be probed independently via \textit{di}-Higgs production at the collider experiments as well as via the detection of gravitational waves (GW). There are three (one) dimension-6 SMEFT operators that simultaneously modify the Higgs potential at tree (1-loop) level and contribute to the \textit{di}-Higgs production at the hadron colliders. With \textit{di}-Higgs production being suppressed at current LHC runs, we aim to probe this production at high luminosity (HL) and high energy (HE) runs of the LHC to achieve better sensitivity of dimension-6 SMEFT operators. The correlations among these operators are analyzed in the context of probing FO-EWPT, emphasizing the complementarity between future GW observations and upgraded LHC searches.

2408.07498 2026-06-11 math.AP stat.ML 版本更新

Wasserstein Gradient Flows of MMD Functionals with Distance Kernel and Cauchy Problems on Quantile Functions

距离核MMD泛函的Wasserstein梯度流及分位数函数上的Cauchy问题

Richard Duong, Viktor Stein, Robert Beinert, Johannes Hertrich, Gabriele Steidl

AI总结 研究负距离核下最大均值差异泛函的Wasserstein梯度流,通过将Wasserstein-2空间等距嵌入分位数函数空间,将梯度流转化为L2上的Cauchy问题并给出解公式,证明了流的正则性。

Comments We corrected the implicit Euler scheme in our code and updated the plots. Also, a minor mistake in the def. (14) and an error in the proof of Thm. 3.5 have been corrected. We thank the anonymous contributors for their valuable feedback, further improving the clarity of the paper. 48 pages, 23 figures, comments welcome!

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AI中文摘要

我们全面描述了实直线上最大均值差异(MMD)泛函 $\mathcal F_\nu:= \text{MMD}_K^2(\cdot, \nu)$ 朝向给定目标测度 $\nu$ 的Wasserstein梯度流,其中我们关注负距离核 $K(x,y):= -|x-y|$。在一维情况下,Wasserstein-2空间可以等距嵌入到分位数函数的锥 $\mathcal C(0,1) \subset L_2(0,1)$ 中,从而通过 $L_2(0,1)$ 上相关Cauchy问题的解来刻画Wasserstein梯度流。基于在 $L_2(0,1)$ 上构造 $\mathcal F_\nu$ 的适当对应物及其次微分,我们给出了Cauchy问题的解。对于离散目标测度 $\nu$,这导致一个分段线性解公式。我们证明了流在 $\mathcal C(0,1)$ 子集上的不变性和光滑性。对于某些 $\mathcal F_\nu$ 流,这意味着初始点测度立即变得绝对连续,并随时间保持。最后,我们通过使用隐式欧拉格式的各种数值例子说明了流的行为,该格式可通过二分法轻松计算。对于连续目标 $\nu$,也可以使用显式欧拉格式,尽管收敛保证有限。

英文摘要

We give a comprehensive description of Wasserstein gradient flows of maximum mean discrepancy (MMD) functionals $\mathcal F_ν:= \text{MMD}_K^2(\cdot, ν)$ towards given target measures $ν$ on the real line, where we focus on the negative distance kernel $K(x,y) := -|x-y|$. In one dimension, the Wasserstein-2 space can be isometrically embedded into the cone $\mathcal C(0,1) \subset L_2(0,1)$ of quantile functions leading to a characterization of Wasserstein gradient flows via the solution of an associated Cauchy problem on $L_2(0,1)$. Based on the construction of an appropriate counterpart of $\mathcal F_ν$ on $L_2(0,1)$ and its subdifferential, we provide a solution of the Cauchy problem. For discrete target measures $ν$, this results in a piecewise linear solution formula. We prove invariance and smoothing properties of the flow on subsets of $\mathcal C(0,1)$. For certain $\mathcal F_ν$-flows this implies that initial point measures instantly become absolutely continuous, and stay so over time. Finally, we illustrate the behavior of the flow by various numerical examples using an implicit Euler scheme, which is easily computable by a bisection algorithm. For continuous targets $ν$, also the explicit Euler scheme can be employed, although with limited convergence guarantees.

2512.03517 2026-06-11 cond-mat.mtrl-sci 版本更新

Layered XZnBi (X = Rb, Cs) with Pudding-Mold Bands, Complex Fermi Surfaces and Low Thermal Conductivity: A First-Principles Study of Thermoelectric Properties

层状XZnBi (X = Rb, Cs) 的布丁模能带、复杂费米面与低热导率:热电性质的第一性原理研究

Aadil Fayaz Wani, Nirma Kumari, SuDong Park, Byungki Ryu

AI总结 通过第一性原理计算和玻尔兹曼方程,研究了层状Zintl化合物XZnBi (X=Rb, Cs)的堆叠顺序对热电性能的影响,发现其具有高能带简并度、布丁模能带和低热导率,在900 K下ZT值最高达2.42(CRTA)或0.52(含电声耦合)。

Comments There was an error in integrating the relaxation time data with boltztrap2 code. This results in: 1. The wrong prediction of transport coefficients discussed in section 3.5. 2. The final conclusion of the manuscript was not consistent with the results. 3. The predicted ZT values were wrongly computed

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AI中文摘要

层状Zintl化合物因其多种元素组合和层内堆叠顺序的灵活性,展现出显著的热电参数可调性。本文通过第一性原理计算和玻尔兹曼方程,研究了理论预测的层状Zintl化合物XZnBi (X = Rb, Cs)中堆叠顺序对热电性质的影响。这些材料是半导体,带隙适中,范围为0.44至0.52 eV。由于晶体对称性,价带最大值存在六个相同的空穴口袋。这导致了高能带简并度,但同时促进了谷间散射。而对于导带,费米面由单个但高度各向异性的准二维电子口袋组成,沿z轴呈圆柱形。这种费米面是布丁模能带形状的特征。它促进了重电子质量和轻电子质量的独特组合,同时优化了塞贝克系数和电导率。首先,使用恒定弛豫时间近似(CRTA)或电子-声子耦合矩阵元(el-ph)计算电子输运系数。然后将计算出的弛豫时间与输运结果相结合,以获得热电参数的实际值。三声子散射分析揭示了这些化合物中低于2 W/m/K的低热导率($k_{l}$)。$k_{l}$也依赖于堆叠顺序,AB堆叠的值约为AA堆叠的一半。这些综合因素导致在900 K时ZT值较高,使用CRTA时最高达到2.42,包含el-ph时达到0.52。该研究突出了XZnBi系统作为有前途的热电材料的潜力,以及堆叠和el-ph在准确评估热电性质中的关键作用。

英文摘要

Layered Zintl compounds exhibit significant tunability of thermoelectric (TE) parameters facilitated by their multiple elemental combinations and flexibility in stacking order within the layers. In this work, the effect of stacking order on TE properties of theoretically predicted layered Zintl compounds XZnBi (X = Rb, Cs) is studied using 1st-principles calculations and Boltzmann equations. The materials are semiconductors having moderate band gaps ranging from 0.44 to 0.52 eV. There exist six identical hole pockets for valence band maxima due to the crystal symmetry. This leads to high band degeneracy but simultaneously promotes intervalley scatterings. While as for conduction bands, the Fermi surface consists of a single but highly anisotropic, quasi-two dimensional electron pockets with cylindrical shape along z-axis. This kind of Fermi surface is a characteristic of a pudding mold band shape. It facilitates a unique combination of heavy and light electron masses, simultaneously optimizing Seebeck coefficient and electrical conductivity. At first, electronic transport coefficients are calculated using constant relaxation time approximation (CRTA) or electron-phonon coupling matrix elements (el-ph). The calculated relaxation times are then integrated with transport results to get the realistic values of TE parameters. The analysis of three-phonon scattering reveals low thermal conductivity ($k_{l}$) below 2 W/m/K in these compounds. The $k_{l}$ also depends on stacking order with the values of nearly half in AB stacking as compared to that of AA stacking. These combined factors lead to a high ZT at 900 K, reaching to a maximum of 2.42 using CRTA and 0.52 when el-ph are included. The study highlights the potential of XZnBi systems as promising TE materials as well as the critical roles of stacking and el-ph in accurately evaluating TE properties.

2508.20464 2026-06-11 cs.HC 版本更新

Human-Centered Design for Connected Automation: Predicting Pedestrian Crossing Intentions

面向互联自动化的人本设计:预测行人过街意图

Sanaz Motamedi, Viktoria Marcus, Griffin Pitts

AI总结 通过扩展计划行为理论,研究影响行人与L5级自动驾驶系统交互时过街决策的因素,发现感知安全性和理解对意图影响最大,为设计eHMI和V2X通信策略提供指导。

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AI中文摘要

全球每年119万交通死亡事故中,超过一半涉及行人等弱势道路使用者,其中很大比例归因于人为错误。L5级自动驾驶系统(ADS)有潜力减少此类事故;然而,其有效性不仅取决于自动化性能,还取决于在缺乏传统驾驶员提示的情况下,系统传达意图并与行人安全协调的能力。本研究旨在通过将计划行为理论(TPB)与安全性、信任、兼容性和理解性相结合,对涉及L5级ADS的道路过街场景中行人的决策过程进行建模。一项在线调查(n=212)发现,感知行为控制、态度和社会信息显著影响行人的过街意图,其中感知安全性和理解性对TPB构念的影响最强。研究结果为设计eHMI和协作式V2X通信策略提供了指导,以促进安全的行人-ADS交互,并推进自动驾驶汽车的人本设计。

英文摘要

More than half of the 1.19 million annual traffic fatalities globally involve vulnerable road users, such as pedestrians, with a significant proportion attributable to human error. Level-5 automated driving systems (ADSs) have the potential to reduce these incidents; However, their effectiveness depends not only on automation performance but also on their ability to communicate intent and coordinate safely with pedestrians in the absence of traditional driver cues. This study aims to model pedestrian decision-making in road-crossing scenarios involving level-5 ADSs by extending the Theory of Planned Behavior (TPB) with safety, trust, compatibility, and understanding. An online survey (n = 212) found that perceived behavioral control, attitude, and social information significantly influence pedestrians' crossing intentions, with perceived safety and understanding having the strongest effects on the TPB constructs. The results offer guidance for designing eHMIs and cooperative V2X communication strategies that promote safe pedestrian-ADS interactions and advance human-centered design for autonomous vehicles.

2512.02522 2026-06-11 cond-mat.mes-hall 版本更新

Tuning proximity-induced spin-orbit coupling in graphene/WSe$_{2}$ heterostructures

石墨烯/WSe$_{2}$异质结构中邻近诱导自旋-轨道耦合的调控

Tobias Rockinger, Bálint Szentpéteri, Szabolcs Csonka, Marina Marocko, Julia Amann, Ziyang Gan, Antony George, Andrey Turchanin, Kenji Watanabe, Takashi Taniguchi, Dieter Weiss, Péter Makk, Jonathan Eroms

AI总结 通过弱反局域化测量,实验证实石墨烯/WSe$_{2}$异质结构中邻近诱导自旋-轨道耦合强度与扭转角强相关,并验证了机械压力和电场对其的调控。

Comments 10 pages, 12 figures, Supplemental Material appended

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Journal ref
Phys. Rev. B 113, 245414 (2026)
AI中文摘要

最近,在由单层石墨烯(ML-G)和过渡金属二硫属化物(TMDCs)如WSe$_{2}$组成的异质结构中观察到了邻近诱导的自旋-轨道耦合(SOC)。先前的研究也证明了通过施加机械压力和电场可以成功调控石墨烯/WSe$_{2}$异质结构中的SOC。此外,理论计算预测邻近诱导的SOC强烈依赖于石墨烯与TMDC之间的扭转角。在这里,我们将这些预测在ML-G/ML-WSe$_{2}$/hBN异质结构中进行实验测试,其中扭转角通过对齐断裂边缘和石墨烯的晶体学蚀刻来确定。通过进行弱反局域化测量,我们确定了Rashba型SOC($\lambda_\mathrm{R}$)和谷Zeeman型SOC($\lambda_\mathrm{VZ}$)的强度。我们的实验证实了邻近诱导的SOC与扭转角的强依赖性,与理论预测一致。最后,我们展示了通过机械压力对SOC强度的可调性,这与早期的发现一致。

英文摘要

Recently, proximity-induced spin-orbit coupling (SOC) has been observed in heterostructures consisting of monolayer graphene (ML-G) and transition metal dichalcogenides (TMDCs) such as WSe$_{2}$. Successful tuning of SOC in graphene/WSe$_{2}$ heterostructures by applying mechanical pressure and electric fields was also demonstrated in previous studies. In addition, theoretical calculations predicted a strong dependence of the proximity-induced SOC on the twist angle between graphene and TMDC. Here, we put these predictions to experimental test in ML-G/ML-WSe$_{2}$/hBN-heterostructures, where the twist angle is determined by aligning fractured edges, and by crystallographic etching of graphene. By performing weak anti-localization measurements, we determine the strength of the Rasbha-type SOC ($λ_\mathrm{R}$) and the valley-Zeeman-type SOC ($λ_\mathrm{VZ}$). Our experiments confirm a strong twist angle dependence of the proximity-induced SOC in agreement with theoretical predictions. Finally, we demonstrate the tunability of the SOC strength via mechanical pressure, which is in agreement with earlier findings.

2512.02164 2026-06-11 hep-th 版本更新

Universality of pseudoentropy for deformed spheres in dS/CFT

dS/CFT中变形球面的伪熵普适性

Giorgos Anastasiou, Ignacio J. Araya, Avijit Das, Javier Moreno

AI总结 本文通过dS/CFT对应,推导了球面纠缠面小形变下伪熵的普适修正,发现二次项由AdS/CFT中应力张量两点关联函数系数的解析延拓控制,并推广到高曲率引力,表明非幺正全息CFT的普适行为。

Comments 8 pages, 2 figures, published in PRD

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AI中文摘要

我们在de Sitter/共形场论(dS/CFT)对应中,确定了球形纠缠面小形变下伪熵的普适部分。形变参数二次阶的领头阶修正由AdS/CFT中应力-能量张量两点关联函数系数的解析延拓控制(即$\left. L_{*} \right|_{\text{AdS}}\rightarrow -i \left. L_{*} \right|_{\text{dS}}$),从而确立了球面作为局部极值点。相同的结构在高曲率理论中也成立,我们以二次曲率引力为例进行了显式检验,表明在非幺正全息CFT中具有普适行为。我们的发现将Mezei公式推广到dS/CFT框架,并表明dS全息中伪熵的形状依赖性与AdS空间中纠缠熵的形状依赖性相似。因此,我们推测该系数是非幺正CFT对偶的$C_T$。

英文摘要

We determine the universal part of pseudoentropy for small shape deformations of spherical entangling surfaces in the context of de Sitter/conformal field theory (dS/CFT) correspondence. The leading correction at quadratic order in the deformation parameter is controlled by the analytic continuation of the coefficient of the two-point stress-energy tensor correlator in AdS/CFT (i.e., $\left. L_{*} \right|_{\text{AdS}}\rightarrow -i \left. L_{*} \right|_{\text{dS}}$), thereby establishing the sphere as a local extremum. The same structure holds in higher-curvature theories, as we check explicitly for quadratic curvature gravity, suggesting a universal behavior across non-unitary holographic CFTs. Our findings extend the Mezei formula to the dS/CFT setting and indicate that the shape dependence of pseudoentropy in dS holography resembles that of entanglement entropy in AdS space. Thus, we conjecture this coefficient to be the $C_T$ for the non-unitary CFT dual.

2512.01558 2026-06-11 physics.comp-ph 版本更新

Neural Network Perturbation Theory (NNPT): Learning Residual Corrections from Exact Solutions

神经网络微扰理论 (NNPT):从精确解学习残差修正

Zhenhao Chen, Mutian Shen, Boris Fain, Zohar Nussinov

AI总结 提出神经网络微扰理论,通过从精确解中学习残差扰动来预测复杂物理系统,在三体问题中验证了容量随混沌度非单调变化的现象。

Comments About to submit to Physical Review E

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AI中文摘要

许多复杂物理系统自然分解为一个精确可解的部分加上一个微扰修正。我们不直接使用神经网络分析复杂物理系统,而是引入神经网络微扰理论(NNPT)——一种修正学习方法,在解析减去已知精确解后预测残差扰动。以引力三体问题为测试平台,我们改变木星质量从物理值的0.05倍到30倍,同时保持网络架构固定。采用1%容差的等精度协议揭示了意外的非单调容量曲线:容量在晚期可积区域(3x32,2242个参数)的f=5处达到峰值,在过渡区域(f~15-17)保持较高水平,然后在完全混沌区域(f>=17,仅需2x32,1186个参数)下降——比峰值减少47%。在辛积分器能量守恒优于2x10^{-4}的条件下,这一反直觉现象反映了真实的物理结构而非数值伪影。顺序修正实验显示可忽略的改进(||y2||/||y1||~0.997),证实单阶段网络无需层次分解即可捕获主导微扰特征。在f_c=16.6±2.8处的容量转变与Chirikov共振重叠准则一致。中等复杂度区域施加最大容量需求,而完全混沌动力学经历遍历平滑——轨迹特定波动成为不可约噪声,仅留下需要更少参数的统计平滑修正。

英文摘要

Many complex physical systems naturally decompose into an exactly solvable component augmented by a perturbative correction. Rather than directly employing neural networks to analyze complex physical systems, we introduce Neural Network Perturbation Theory (NNPT)--a correction learning approach that predicts residual perturbations after analytically subtracting known exact solutions. Using the gravitational three-body problem as testbed, we vary Jovian mass from f=0.05 to 30 times its physical value while holding network architecture fixed. An equalized-accuracy protocol with 1% tolerance reveals an unexpected non-monotonic capacity profile: capacity peaks at f=5 in the late integrable regime (3x32, 2242 parameters), remains elevated through the transition region (f~15-17), then decreases in the fully chaotic regime (f>=17, requiring only 2x32 with 1186 parameters)--a 47% reduction from peak. With symplectic integrator energy conservation below 2x10^{-4}, this counterintuitive phenomenon reflects genuine physical structure rather than numerical artifacts. Sequential correction experiments show negligible refinement (||y2||/||y1||~0.997), confirming single-stage networks capture dominant perturbative features without hierarchical decomposition. The capacity transition at f_c=16.6+-2.8 aligns with Chirikov's resonance-overlap criterion. Intermediate-complexity regimes impose maximal capacity requirements, while fully chaotic dynamics undergo ergodic smoothing--trajectory-specific fluctuations become irreducible noise, leaving only statistically smooth corrections requiring fewer parameters.

2511.18540 2026-06-11 math.CO 版本更新

Extremality in semidistributive lattices

半分配格中的极值性

Adrien Segovia

AI总结 研究极值、左模、同余一致和半分配格的性质,给出左模格的边标号刻画及构造条件,证明同余一致格可壳性等价于极值性,并推广Dilworth定理到半分配极值格。

Comments Added the result obtained by computer that the Cambrian lattices of type $E_8$ have all order dimension 8

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AI中文摘要

我们建立了关于极值格、左模格、同余一致格和半分配格的若干独立结果。通过边标号得到了左模格的等价刻画,以及在构造同余正规格时确保左模性或极值性的加倍步骤的充要条件。我们证明了一个同余一致格是可壳的当且仅当它是极值的。我们通过构造一个反例回答了Barnard的问题,表明典范连接复形的诱导子复形不一定是这样的复形。最后,我们证明了半分配极值格的序维数等于其伽罗瓦图补图的色数,推广了Dilworth关于分配格的一个定理。作为应用,我们确定了Hochschild格、抛物Tamari格以及一些挠类格的维数推广。

英文摘要

We establish several independent results concerning extremal, left modular, congruence uniform, and semidistributive lattices. An equivalent characterization of left modular lattices is obtained in terms of edge-labellings, together with necessary and sufficient conditions on the doubling steps in the construction of congruence normal lattices that ensure left modularity or extremality. We prove that a congruence uniform lattice is shellable if and only if it is extremal. We answer a question of Barnard by constructing a counterexample showing that an induced subcomplex of a canonical join complex need not itself be such a complex. Finally, we show that the order dimension of a semidistributive extremal lattice equals the chromatic number of the complement of its Galois graph, generalizing a theorem of Dilworth for distributive lattices. As an application, we determine the dimensions of generalizations of the Hochschild lattice, of the parabolic Tamari lattice, and of some lattices of torsion classes.

2511.22452 2026-06-11 physics.optics 版本更新

Metasurface-Enhanced Mid-Infrared Imaging Spectroscopy with Broadband Quantum Cascade Lasers

超表面增强的宽带量子级联激光器中红外成像光谱

Ivan Sinev, Alessio Cargioli, Diego Piciocchi, Felix Ulrich Brikh, Jerome Faist, Hatice Altug

AI总结 提出一种结合宽带梯度超表面与射频调制量子级联激光器的紧凑型中红外成像光谱平台,通过匹配超表面共振与激光发射光谱,实现单帧获取增强吸收条形码图像,将采集时间缩短三个数量级。

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AI中文摘要

中红外光谱通过分子吸收指纹的化学特异性检测,为传感提供了无与伦比的机会。然而,其实际应用受到中红外波段弱光-物质相互作用以及中红外光源低亮度的限制。表面增强红外吸收光谱通过利用共振光子结构,特别是等离激元和频率选择性介质超表面,解决了灵敏度限制。然而,当前SEIRA方法的实现主要依赖于复杂的仪器和扫描组件,如傅里叶变换红外光谱和可调谐外腔量子级联激光器。在这里,我们提出了一种紧凑、高通量的基于成像的SEIRA平台,该平台将宽带梯度超表面与射频调制的QCL相结合,该QCL产生非常宽的瞬时发射光谱(250 cm$^{-1}$),覆盖多个不同分子振动模式的吸收带。通过将紧凑型(1 mm$^2$)宽带梯度超表面的共振光谱与通过色散元件投射在其表面的激光发射相匹配,我们确保每个QCL光谱分量被唯一地寻址,以实现有效的目标电磁场增强。这使得我们能够使用低成本和室温中红外相机,在单帧中获取沉积在超表面上的分析物的增强吸收特征作为条形码图像,从而与基于FTIR和EC QCL的测量相比,将采集时间缩短多达三个数量级。消除了对可调谐光源、笨重光谱仪和昂贵低温探测器的需求,我们的方法能够为各种化学和生物应用实现高通量、小型化和高度特异性的分子诊断。

英文摘要

Mid-infrared (mid-IR) spectroscopy offers unparalleled opportunities in sensing through chemically specific detection of molecular absorption fingerprints. Yet, its practical applications are limited by the weak light-matter interaction in the mid-IR range and low brightness of mid-IR light sources. Surface-enhanced infrared absorption (SEIRA) spectroscopy addresses the sensitivity limitations by leveraging resonant photonic structures, in particular, plasmonic and frequency-selective dielectric metasurfaces. However, current implementations of SEIRA approach mainly rely on complex instruments and scanning components such as Fourier-transform infrared spectroscopy and tunable external cavity quantum cascade lasers (EC QCLs). Here, we present a compact and high-throughput imaging-based SEIRA platform that combines broadband gradient metasurfaces with a radiofrequency-modulated QCL that generates remarkably broad instantaneous emission spectrum (250 cm$^{-1}$) covering absorption bands of multiple distinct molecular vibrational modes. By matching the resonance spectrum of the compact (1 mm$^2$) broadband gradient metasurface with the laser emission projected on its surface through a dispersive element, we ensure that every QCL spectral component is uniquely addressed for an efficient targeted enhancement of the electromagnetic field. This enables us to use a low-cost and room-temperature mid-IR camera, acquiring in a single frame the enhanced absorption signatures of analytes deposited on the metasurface as a barcode image, thus reducing the acquisition time by up to 3 orders of magnitude compared to the FTIR and EC QCL based measurements. Eliminating the need for tunable light sources, bulky spectrometers, and expensive low-temperature detectors, our approach enables high-throughput, miniaturized, and highly specific molecular diagnostics for diverse chemical and biological applications.

2511.22032 2026-06-11 cond-mat.mtrl-sci 版本更新

Electric Current Control of Helimagnetic Chirality from a Multidomain State in the Helimagnet MnAu$_2$

螺旋磁体MnAu$_2$中多畴态的手性电流控制

Yuta Kimoto, Hidetoshi Masuda, Jun-ichiro Ohe, Shoya Sakamoto, Takeshi Seki, Yoshinori Onose

AI总结 研究螺旋磁体MnAu$_2$中电流驱动多畴态向单畴态转变的动力学,发现转变阈值电流远低于单畴手性反转的阈值,且转变后手性取决于磁场与电流的相对方向。

Comments 12 pages, 13 figures

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Journal ref
Phys. Rev. Research 8, L022034 (2026)
AI中文摘要

在本文中,我们研究了螺旋磁体MnAu$_2$中电流作用下的畴壁动力学。我们发现,在一定的温度和磁场范围内,从多畴态到单手性畴态的转变阈值电流远低于单手性畴的手性反转阈值。转变后的手性取决于磁场与电流是平行还是反平行。基于Landau-Lifshitz-Gilbert方程的数值计算再现了实验观测结果。这些结果表明,螺旋磁体中的畴壁具有高迁移率。

英文摘要

In this paper, we study the domain wall dynamics under electric current in the helimagnet MnAu$_2$. We have found that the threshold electric current of the transition from a multidomain state to a single-chiral domain state in a magnetic field is much lower than that of chirality reversal from a single-chiral domain within certain ranges of temperature and magnetic field. The chirality after the transition depends on whether the magnetic field and electric current were parallel or antiparallel. Numerical calculations based on the Landau-Lifshitz-Gilbert equation reproduced the experimental observations. These results indicate that the domain walls are highly mobile in the helimagnet.

2507.07428 2026-06-11 math.OC 版本更新

Relocated Fixed-Point Iterations with Applications to Variable Stepsize Resolvent Splitting

重定位不动点迭代及其在变步长预解分裂中的应用

Felipe Atenas, Heinz H. Bauschke, Minh N. Dao, Matthew K. Tam

AI总结 提出一种收敛框架,允许迭代算法中的非扩张算子族无公共不动点,通过重定位步骤实现变步长预解分裂,并应用于Douglas-Rachford算法。

Comments 29 pages

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AI中文摘要

在这项工作中,我们开发了一个迭代算法的收敛框架,其更新可以由一个单参数族的非扩张算子描述。在该框架中,涉及主要算法算子的每一步之后都跟随第二步,该步将当前算子的不动点“重定位”到下一个算子。因此,我们的分析不要求非扩张算子族具有公共不动点,而这在文献中经常被假设。我们的分析使用了非扩张算子的半闭性原理的参数扩展。作为我们收敛结果的一个应用,我们开发了基于图的Douglas-Rachford算法的一个版本,用于寻找$N\geq 2$个极大单调算子之和的零点,该算法不要求预解参数在迭代过程中保持不变。

英文摘要

In this work, we develop a convergence framework for iterative algorithms whose updates can be described by a one-parameter family of nonexpansive operators. Within the framework, each step involving one of the main algorithmic operators is followed by a second step which ''relocates'' fixed points of the current operator to the next. As a consequence, our analysis does not require the family of nonexpansive operators to have a common fixed point, as frequently assumed in the literature. Our analysis uses a parametric extension of the demiclosedness principle for nonexpansive operators. As an application of our convergence results, we develop a version of the graph-based extension of the Douglas--Rachford algorithm for finding a zero of the sum of $N\geq 2$ maximally monotone operators, which does not require the resolvent parameter to be constant across iterations.

2511.06432 2026-06-11 math.AP 版本更新

Scattering of the defocusing Calogero--Moser derivative nonlinear Schrödinger equation

散焦 Calogero--Moser 导数非线性薛定谔方程的散射

Xi Chen

AI总结 利用 Gérard 型显式公式,证明具有某些初始数据的散焦 CM-DNLS 方程解的散射结果,并通过 Lax 算子的畸变傅里叶变换刻画散射项。

Comments Lemma 4.1 has now been extended to the (L^2) setting. This is the complete version of the paper for (L^2) initial data

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AI中文摘要

本文研究了散焦 Calogero--Moser 导数非线性薛定谔方程 (CM-DNLS) 解的长时间行为。利用 Gérard 型显式公式,我们证明了该方程在初始数据属于 $H_{+}^{1,\alpha}(\mathbb{R}): = \{u \in H_{+}^1(\mathbb{R}): |x|^{\alpha} u \in L^2(\mathbb{R})\}$(其中 $\alpha>0$)时的散射结果。我们还通过 Lax 算子相关的畸变傅里叶变换刻画了散射项。这是首批将 Gérard 型显式公式应用于研究可积方程长时间行为的工作之一,适用于比先前研究的理性情形更广泛的初始数据类。

英文摘要

In this paper, we study the long time behavior of solutions to the defocusing Calogero--Moser derivative nonlinear Schrödinger equation (CM-DNLS). Using the Gérard-type explicit formula, we prove the scattering result of solutions to this equation with initial data in $L_{+}^{2,α}(\mathbb R): = \{u \in L_{+}^2(\mathbb{R}): |x|^α u \in L^2(\mathbb{R})\}$ with some $α>0$. We also characterize the scattering term using the distorted Fourier transform associated with the Lax operator. This is one of the first works that apply the Gérard-type explicit formula to study the long-time behavior of an integrable equation for a broad class of initial data, beyond the previously studied rational cases.

2511.19615 2026-06-11 astro-ph.CO astro-ph.GA astro-ph.IM 版本更新

Improving divergence cleaning in cosmological SPMHD simulations

改进宇宙学SPMHD模拟中的散度清理

Ulrich P. Steinwandel, Daniel J. Price

AI总结 将约束双曲/抛物散度清理算法应用于宇宙学SPMHD代码OpenGadget3,在膨胀宇宙框架中修正控制方程,有效减少磁场散度误差,并在星系团外围将磁场放大5-10倍。

Comments 15 pages, 13 figures, comments welcome! Accepted by MNRAS

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AI中文摘要

我们将约束双曲/抛物散度清理算法实现到宇宙学平滑粒子磁流体动力学(SPMHD)代码{\sc OpenGadget3}中,修改控制方程,使得该方案能够在膨胀宇宙框架中一致地应用。这确保了磁场中的散度误差被主动传播出去并衰减,而不是像先前采用的Powell八波方法那样随流平流并部分由源项控制。我们在一系列标准测试问题——人工散度脉冲的平流、Orszag-Tang涡旋、Brio-Wu激波管以及磁化Zeldovich薄饼——上验证了该实现,确认该方案在保持正确物理演化的同时减少了散度误差。然后,我们将该方法应用于一个质量$M_\mathrm{200c} \approx 10^{15}~\mathrm{M}_{\odot}$的大质量星系团的完全宇宙学模拟,并直接与仅Powell方法进行比较。星系团的整体密度结构在散度清理选择下基本不变,星系团核心的磁场几何和强度保持相似。然而,在星系团外围($r \approx 1$--$3~h^{-1}$~Mpc),磁场比仅Powell运行放大了5-10倍,而整个星系团体积内的散度误差降低了2-3个数量级。我们的结果表明,准确的散度控制对于捕捉星系团低密度、分辨率较差的外围区域的磁场放大至关重要。

英文摘要

We implement the constrained hyperbolic/parabolic divergence cleaning algorithm into the cosmological smoothed particle magnetohydrodynamics (SPMHD) code {\sc OpenGadget3}, modifying the governing equations so that the scheme can be applied consistently in an expanding cosmological framework. This ensures that divergence errors in the magnetic field are actively propagated away and damped, rather than advected with the flow and partially controlled by source terms as in the previously employed Powell eight-wave approach. We validate the implementation on a series of standard test problems -- the advection of an artificial divergence pulse, the Orszag--Tang vortex, the Brio--Wu shock tube, and a magnetised Zeldovich pancake -- which confirm that the scheme reduces divergence errors while preserving the correct physical evolution. We then apply the method to a fully cosmological simulation of a massive galaxy cluster with $M_\mathrm{200c} \approx 10^{15}~\mathrm{M}_{\odot}$, and compare directly to the Powell-only approach. The overall density structure of the cluster is largely unchanged by the choice of divergence cleaning, and the magnetic field geometry and strength in the cluster core remain similar. In the cluster outskirts ($r \approx 1$--$3~h^{-1}$~Mpc), however, the magnetic field is amplified by a factor of 5--10 compared to the Powell-only run, while the divergence error is reduced by 2--3 orders of magnitude throughout the cluster volume. Our results suggest that accurate divergence control is essential for capturing magnetic field amplification in the low-density, poorly resolved outskirts of galaxy clusters.

2507.13749 2026-06-11 math.CT 版本更新

Classifying localizing subcategories of a locally coherent category

局部凝聚范畴的局部化子范畴分类

Reza Sazeedeh

AI总结 本文通过原子谱的开子集分类局部凝聚Grothendieck范畴的有限型局部化子范畴,并证明若原子谱相等则范畴局部诺特,最后应用于交换凝聚环。

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AI中文摘要

设 $\cA$ 为局部凝聚 Grothendieck 范畴,$\fp\cA$ 为由有限表现对象构成的 $\cA$ 的全子范畴,$\ASpec\cA$ 为 $\cA$ 的原子谱。本文通过 $\ASpec\cA$ 的开子集分类 $\cA$ 的有限型局部化子范畴。我们研究 $\ASpec\fp\cA$ 并证明若 $\ASpec\fp\cA=\ASpec\cA$,则 $\cA$ 是局部诺特的。作为应用,我们将研究特化到交换凝聚环的情形。

英文摘要

Let $\cA$ be a locally coherent Grothendieck category, $\fp\cA$ be the full subcategory of $\cA$ consisting of finitely presented objects and $\ASpec\cA$ be the atom spectrum of $\cA$. In this paper, we classify localizing subcategories of finite type of $\cA$ via open subsets of $\ASpec\cA$. We investigate $\ASpec\fp\cA$ and show that if $\ASpec\fp\cA=\ASpec\cA$, then $\cA$ is locally noetherian. As an application, we specialize our investigation to the case of commutative coherent rings.

2507.11919 2026-06-11 eess.SP 版本更新

Time-Frequency Mode Decomposition for Wind Turbine Vibration Monitoring under Variable Speed Operation

变速运行下风力发电机振动监测的时频模态分解

Wei Zhou, Wei-Jian Li, Desen Zhu, Hongbin Xu, Wei-Xin Ren

AI总结 提出时频模态分解(TFMD)方法,通过分割短时傅里叶变换支撑区域并重构模态,无需预设模态数即可分离变速运行下的非平稳转子阶次分量,在合成和实验数据中验证了低重构误差和有效谐波提取能力。

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AI中文摘要

变速运行下的风力发电机振动监测需要分离非平稳的转子阶次分量,这些分量的频率和运行区间取决于运行状态。这些分量在短时傅里叶变换(STFT)平面中占据局部支撑区域,而非固定的频谱带或连续脊线。本研究提出时频模态分解(TFMD),一种基于分割的方法,用于估计连通的STFT支撑区域并从每个区域重构一个模态。TFMD选择高幅值的STFT系数,通过连通分量标记进行分组,滤除小区域,通过掩膜扩张和冲突解决扩展保留的支撑区域,并通过逆STFT重构模态。在包含六个运行状态的合成响应中,TFMD分离了每个状态的分量,并在无需预先指定分量数量的情况下产生低重构误差。在受控的风力发电机叶片应变实验中,首次分解重构了九个模态,其峰值频率接近标称的每转一次频率,且能量集中在相应的运行区间。残差分解进一步揭示了较弱的谐波结构。这些结果支持TFMD作为变速运行下振动分析的实用候选方法,而海上现场应用需要在环境载荷和实测运行参考下进行验证。

英文摘要

Wind turbine vibration monitoring under variable speed operation requires separating nonstationary rotor-order components whose frequencies and operating intervals depend on operating state. These components can occupy local support regions in the short-time Fourier transform (STFT) plane rather than fixed spectral bands or continuous ridges. This study presents time-frequency mode decomposition (TFMD), a segmentation-based method that estimates connected STFT support regions and reconstructs one mode from each region. TFMD selects STFT coefficients with high magnitude, groups them by connected component labeling, filters small regions, expands retained support regions with mask dilation and conflict resolution, and reconstructs modes by inverse STFT. In a synthetic response with six operating states, TFMD separates the components of each state and produces low reconstruction error without specifying the number of components in advance. In a controlled wind turbine blade strain experiment, the first decomposition reconstructs nine modes whose peak frequencies lie near the nominal once per revolution frequencies and whose energies are concentrated in the corresponding operating intervals. Residual decomposition further reveals weaker harmonic structure. These results support TFMD as a practical candidate for vibration analysis under variable speed operation, while offshore field use requires validation under environmental loading and with measured operating references.

2511.19196 2026-06-11 astro-ph.SR 版本更新

Observing bright pulsating white dwarfs with PLATO: A new window into the late stages of stellar evolution

用PLATO观测明亮脉动白矮星:恒星演化晚期的新窗口

Murat Uzundag, Alejandro H. Corsico, Nicholas Jannsen, Mukremin Kilic, Pierre Bergeron, Leandro G. Althaus, J. J. Hermes, Ingrid Pelisoli, Keaton J. Bell, Francisco C. De Geronimo, Leila M. Calcaferro, Zsofia Bognar, Valerie Van Grootel, Maria E. Camisassa, Paulina Sowicka, Steven D. Kawaler, S. O. Kepler, Roberto Silvotti, Marcelo M. Miller Bertolami, Margarida Cunha

AI总结 本文论证了利用PLATO任务研究明亮脉动白矮星(包括氢缺乏型和氢丰富型)的可行性,通过模拟观测展示了探测低至0.1 mma振幅脉动模式的能力,旨在揭示白矮星内部结构、化学分层及演化历史。

Comments Accepted for publication in Experimental Astronomy

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AI中文摘要

我们提出了利用PLATO任务的能力研究明亮脉动白矮星的科学案例,涵盖宽光谱范围,包括氢缺乏型(GW Vir和DBV星)和氢丰富型(经典DAV、脉动极低质量DA白矮星和超大质量DA白矮星)。PLATO卓越的光度精度、长时间连续监测和广泛的天空覆盖有望在白矮星星震学中带来变革性进展。我们的关键目标包括探测白矮星的内部结构和化学分层、检测长时间尺度上脉动模式的长期变化,以及发现罕见或以前未知的脉动星类别。为评估可行性,我们利用PLATO补充科学目录结合Gaia DR3,在PLATO南天LOPS2场中构建了650颗白矮星候选体样本,并通过光度建模推导了大气参数。该样本包括118颗DA白矮星(含23颗ZZ Cet候选体)和41颗非DA白矮星(含35颗DBV候选体)。使用PlatoSim进行的模拟观测表明,PLATO能够探测到振幅低至0.1 mma的白矮星脉动模式,具体取决于星等、观测时长、像素位置和参与相机的数量。我们提供了这些参数在典型范围内的详细探测极限和可见性预测。此外,我们强调了与Gaia天体测量、TESS测光和针对性光谱巡天的强协同作用,这些将共同实现稳健的模态识别和详细的恒星建模。总体而言,这些努力将开启对白矮星起源、演化和内部物理以及其行星系统命运的前所未有的洞察。

英文摘要

We present the scientific case for exploiting the capabilities of the PLATO mission to study bright pulsating white dwarfs across a wide spectral range, including hydrogen-deficient types (GW Vir and DBV stars) and hydrogen-rich classes (classical DAVs, pulsating extremely low-mass DA white dwarfs, and ultra-massive DA white dwarfs). PLATOs exceptional photometric precision, long-duration continuous monitoring, and extensive sky coverage promise transformative advances in white dwarf asteroseismology. Our key objectives include probing the internal structure and chemical stratification of white dwarfs, detecting secular changes in pulsation modes over extended timescales, and discovering rare or previously unknown classes of pulsators. To assess feasibility, we constructed a sample of 650 white dwarf candidates identified within PLATOs Southern LOPS2 field using the PLATO complementary science catalogue combined with Gaia DR3, and derived atmospheric parameters through photometric modeling. This sample comprises 118 DA white dwarfs (including 23 ZZ Ceti candidates), and 41 non-DAs (including 35 DBV candidates). Simulated observations using PlatoSim demonstrate that PLATO will be capable of detecting white dwarf pulsation modes with amplitudes as low as 0.1 mma depending on stellar magnitude, observation duration, pixel location, and the number of contributing cameras. We provide detailed detection limits and visibility forecasts for known pulsators across a representative range of these parameters. Furthermore, we emphasize strong synergies with Gaia astrometry, TESS photometry, and targeted spectroscopic campaigns, which together will enable robust mode identification and detailed stellar modeling. Collectively, these efforts will unlock unprecedented insights into white dwarf origins, evolution and internal physics, and the fate of their planetary systems.

2511.19191 2026-06-11 cond-mat.quant-gas 版本更新

Probing Bardeen-Cooper-Schrieffer pairing and quasiparticle formation in ultracold gases by Rydberg atom spectroscopy

通过里德伯原子光谱探测超冷气体中的巴丁-库珀-施里弗配对和准粒子形成

Emilio Ramos Rodríguez, Marcel Gievers, Richard Schmidt

AI总结 提出利用里德伯杂质作为光谱传感器,通过功能行列式方法直接测量超流间隙,并揭示库珀对是否被破坏或完整捕获,建立了里德伯原子光谱作为强关联物质局部探针的方法。

Comments 13 pages, 9 figures

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AI中文摘要

从微观到宏观尺度局部探测费米子超流体中的配对一直是一个长期挑战。在这里,我们研究了一种新方法,该方法使用里德伯杂质作为光谱传感器,探测周围超冷配对费米子的强关联态。里德伯电子的扩展波函数诱导出一个有限程势,可以从BCS介质中束缚原子,形成分子态。因此,杂质的光学吸收光谱编码了关键的多体性质。利用功能行列式方法,我们通过二聚体和三聚体峰的频移直接测量超流间隙。光谱还揭示了库珀对是被破坏还是完整捕获。对于静态里德伯原子,我们将这种配对特征与超导间隙导致的正交性灾难抑制联系起来,从而形成明确的极化子准粒子。我们的工作确立了里德伯原子光谱作为强关联物质强大局部探针的地位。

英文摘要

Locally probing pairing in fermionic superfluids, ranging from micro- to macroscopic scales, has been a long-standing challenge. Here, we investigate a new approach that uses Rydberg impurities as a spectroscopic sensor of the surrounding strongly correlated state of ultracold paired fermions. The extended wavefunction of the Rydberg electron induces a finite-range potential that can bind atoms from the BCS medium, forming molecular states. As a consequence, the optical absorption spectrum of the impurity encodes key many-body properties. Using the functional determinant approach, we provide a direct measure of the superfluid gap through frequency shifts of dimer and trimer peaks. The spectra also reveal whether the Cooper pairs are broken or trapped intact. For static Rydberg atoms, we relate this signature of pairing to the suppression of the orthogonality catastrophe due to the superconducting gap resulting in the formation of well-defined polaron quasiparticles. Our work establishes Rydberg atom spectroscopy as a powerful local probe of strongly correlated matter.

2511.18235 2026-06-11 cs.CR 版本更新

EcoDefender: Energy-Efficient Hybrid Anomaly Detection for IoT Edge Gateways

EcoDefender:面向IoT边缘网关的节能混合异常检测

Saeid Jamshidi, Martine Bellaıche, Omar Abdul Wahab

AI总结 提出EcoDefender,一种结合自编码器和孤立森林的边缘混合异常检测框架,通过潜在空间正则化与自适应融合机制实现轻量级无监督检测,在树莓派测试中达到94%准确率、22%CPU使用率和0.45J/次推理能耗。

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AI中文摘要

物联网(IoT)的快速发展催生了大规模、异构的生态系统,这些系统越来越容易受到复杂的分布式网络威胁。然而,许多现有的异常检测系统优先考虑检测准确性,却忽视了系统级约束,如延迟、计算开销和能耗,从而限制了它们在资源受限的边缘网关上的实用性。本文提出EcoDefender,一种面向边缘的混合异常检测框架,该框架将基于自编码器(AE)的潜在表示学习与孤立森林(IF)异常评分相结合,用于IoT流量分析。所提出的架构在传统AE-IF流水线的基础上引入了多项改进,包括异常感知的潜在流形正则化、潜在空间中方差加权的孤立分裂,以及一种可学习的融合机制,该机制在存在潜在分布漂移时自适应地结合重构误差和基于孤立性的异常分数。通过将高维流量特征压缩为紧凑的潜在表示,并在该降维空间中进行异常评分,EcoDefender实现了适用于边缘部署的轻量级且完全无监督的异常检测。在真实IoT流量和分布式树莓派边缘测试平台上的实验评估表明,EcoDefender在保持低计算开销的同时,实现了高达94%的检测准确率,平均CPU使用率为22%,端到端推理延迟为27毫秒。此外,通过设备级功耗监测获得的能量感知测量显示,每次推理的平均能耗为0.45焦耳(相当于0.28克二氧化碳排放),与仅使用AE的基线相比,能耗降低了30%,同时推理吞吐量高达每秒5000个样本。

英文摘要

The rapid growth of the Internet of Things (IoT) has created large-scale, heterogeneous ecosystems that are increasingly vulnerable to sophisticated, distributed cyber threats. However, many existing anomaly detection systems prioritize detection accuracy while overlooking system-level constraints, such as latency, computational overhead, and energy consumption, thereby limiting their practicality for resource-constrained edge gateways. This paper presents EcoDefender, an edge-oriented hybrid anomaly detection framework that combines Autoencoder (AE)-based latent representation learning with Isolation Forest (IF) anomaly scoring for IoT traffic analysis. The proposed architecture introduces several enhancements over conventional AE-IF pipelines, including anomaly-aware latent manifold regularization, variance-weighted isolation splits in the latent space, and a learnable fusion mechanism that adaptively combines reconstruction error and isolation-based anomaly scores in the presence of potential distributional drift. By compressing high-dimensional traffic features into compact latent representations and performing anomaly scoring in this reduced space, EcoDefender enables lightweight and fully unsupervised anomaly detection suitable for edge deployment. An experimental evaluation of realistic IoT traffic and a distributed Raspberry Pi edge testbed demonstrates that EcoDefender achieves up to 94% detection accuracy while maintaining low computational overhead, with an average CPU usage of 22% and an end-to-end inference latency of 27 ms. Furthermore, energy-aware measurements obtained through device-level power monitoring show an average energy consumption of 0.45 J per inference (0.28 g CO2 emissions), representing a 30% reduction in energy consumption compared with AE-only baselines while sustaining inference throughput of up to 5,000 samples per second.

2511.17780 2026-06-11 math.SG math.DG math.GT 版本更新

The h-principle fails for prelegendrians in corank 2 fat distributions

h-原理在余秩2胖分布的前Legendrian子流形中失效

Eduardo Fernández, Álvaro del Pino, Wei Zhou

AI总结 本文研究胖分布中前Legendrian子流形的h-原理,证明在余秩2情况下h-原理在所有维度失效,通过构造无穷多形式同伦类相同但非前Legendrian同痕的环面,并引入前Legendrian稳定化概念,首次在接触拓扑外给出极大非可积分布的刚性例子。

Comments 52 pages, 5 figures. Comments are very welcome. V.2: Added a discussion of the canonical fat distribution on complex projective spaces and proved that formally equivalent prelegendrians cannot be distinguished by the formal Legendrian isotopy class of their lifts. Minor stylistic revisions throughout

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AI中文摘要

我们研究胖分布的$h$-原理问题。胖分布是极大非可积分布,具有自然的辛化和接触化,将接触分布推广到更高余秩。我们关注余秩$2$情形,研究一类自然子流形,称为前Legendrian子流形。其关键特征是它们可以典范地提升为接触化中的Legendrian子流形。我们的主要结果表明,在所有维度中,这些子流形的$h$-原理失效。据我们所知,这是接触拓扑之外,极大非可积分布研究中刚性的第一个例子。首先,我们在标准胖分布$(\mathbb{C}^{2n+1},\mathcal{D}_{\mathrm{std}})$中发现一个无穷族$(2n+1)$-环面,具有以下两个性质:(1) 它们都代表相同的形式前Legendrian类,(2) 但它们不是前Legendrian同痕的,因为它们的Legendrian提升的伪全纯曲线不变量不同。其次,我们在$(\mathbb{C}^{2n+1},\mathcal{D}_{\mathrm{std}})$中定义了前Legendrian稳定化的概念。这允许我们取任意前Legendrian子流形,并产生另一个相同形式类中的前Legendrian子流形,其Legendrian提升是松的。为了证明这些结果,我们还发展了前Legendrian理论的基础。这包括:(1) 在$(\mathbb{C}^{2n+1},\mathcal{D}_{\mathrm{std}})$中引入前投影的概念,(2) 证明伪全纯曲线不变量在胖结构的扰动下是稳健的,从而将我们的结果推广到非标准胖结构,(3) 引入缩放论证,表明任何6维胖结构都允许前Legendrian子流形。

英文摘要

We investigate the $h$-principle problem for fat distributions. These are maximally non-integrable distributions with natural symplectisations and contactisations, that generalize contact distributions to higher corank. We focus on the corank-$2$ case, where we study a natural class of submanifolds, which we call prelegendrians. Their key feature is that they admit a canonical Legendrian lift to the contactisation. Our main results state that the $h$-principle fails for these submanifolds in all dimensions. To the best of our knowledge, this is the first example of rigidity in the study of maximally non-integrable distributions, outside of contact topology. First, we find an infinite family of $(2n+1)$-tori in the standard fat $(\mathbb{C}^{2n+1},\mathcal{D}_{\mathrm{std}})$, with the following two properties: (1) They all represent the same formal prelegendrian class, (2) but they are not prelegendrian isotopic because they are distinguished by pseudoholomorphic curve invariants of their Legendrian lift. Secondly, we define the notion of prelegendrian stabilization in $(\mathbb{C}^{2n+1},\mathcal{D}_{\mathrm{std}})$. This allows us to take an arbitrary prelegendrian and produce another one, in the same formal class, whose Legendrian lift is loose. In order to prove these results we also develop the fundamentals of the theory of prelegendrians. This includes: (1) introducing the notion of front projection in $(\mathbb{C}^{2n+1},\mathcal{D}_{\mathrm{std}})$, (2) proving that pseudoholomorphic curve invariants are robust under perturbations of the fat structure, allowing us to transport our results to non-standard fat structures, (3) introducing a zooming argument showing that any fat structure in dimension $6$ admits prelegendrians.

2511.17546 2026-06-11 physics.atom-ph nucl-ex 版本更新

Reference Quadrupole Moments of Transition Elements from Lamb Shifts in Muonic Atoms

从缪子原子兰姆位移测量过渡元素参考四极矩

S. Rathi, K. von Schoeler, P. Indelicato, B. Ohayon

AI总结 提出利用低温微量热计测量缪子原子2s-2p跃迁的兰姆位移,以高精度确定轻过渡元素(Z=23-30)的绝对电四极矩,可将不确定度降低一个数量级。

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AI中文摘要

我们提出了一种精确测量轻过渡元素($23 \leq Z \leq 30$)绝对电四极矩的新方法。该方法基于对$2s-2p$能级(也称为兰姆位移)进行精密缪子X射线光谱学测量。这些跃迁太弱而无法用色散方法探测,且重叠严重以至于无法用固态探测器分辨。在此,我们建议使用低温微量热计,其在相关能量范围内具有高效率和优异的能量分辨率,并结合最先进的理论计算。通过进行大量计算和实际模拟,我们证明了该方法的可行性。通过这种方式,我们确定,绝对矩的不确定性(将传递到链中所有同位素的四极矩)可以在一天的测量内降低一个数量级。这些精确的参考四极矩为核结构研究以及为开壳层元素中最先进的量子化学计算提供基准提供了有价值的输入。

英文摘要

We present a novel method for accurately measuring the absolute electric quadrupole moments of light transition elements $(23 \leq Z \leq 30 )$. Our approach is based on performing precision muonic x-ray spectroscopy of the $2s-2p$ manifold, which is also referred to as the Lamb shift. These transitions are too weak to be detected with dispersive methods and too overlapping to be resolved by solid-state detectors. Here, we propose the use of cryogenic microcalorimeters, which possess high efficiency and excellent energy resolution in the relevant energy regime, coupled with state-of-the-art theoretical calculations. We demonstrate the feasibility of this approach by performing extensive calculations and realistic simulations. In this way, we establish that the uncertainty in the absolute moment, which is transferred to the quadrupole moments of all isotopes in the chain, could be reduced by up to an order of magnitude within a day of measurement. These precise reference quadrupole moments serve as valuable inputs for nuclear structure studies and for benchmarking state-of-the-art quantum chemistry calculations in open-shell elements.

2511.17381 2026-06-11 cond-mat.str-el 版本更新

Critical Berezinskii-Kosterlitz-Thouless dynamics in the archetypal two-dimensional spin system Ba$_2$CuSi$_2$O$_6$Cl$_2$

典型二维自旋系统Ba$_2$CuSi$_2$O$_6$Cl$_2$中的临界Berezinskii-Kosterlitz-Thouless动力学

K. M. Ranjith, Maxime Dupont, Steffen Krämer, Sylvain Capponi, Edmond Orignac, Nicolas Laflorencie, Nobuyuki Kurita, Hidekazu Tanaka, Mladen Horvatić

AI总结 通过核磁共振和量子蒙特卡洛模拟,研究准二维自旋二聚体化合物Ba₂CuSi₂O₆Cl₂中磁场诱导的三子玻色-爱因斯坦凝聚,揭示了二维BKT型临界涨落,确定了BKT转变温度与奈尔温度之比约为0.74。

Comments 12 pages, 11 figures

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Journal ref
Phys. Rev. B 113 (2026) 224409
AI中文摘要

我们研究了准二维自旋-1/2二聚体化合物Ba$_2$CuSi$_2$O$_6$Cl$_2$中的自旋动力学,该化合物表现出磁场诱导的三子玻色-爱因斯坦凝聚(BEC)。通过核磁共振自旋-晶格弛豫率($T_1^{-1}$)测量结合大规模量子蒙特卡洛(QMC)模拟,我们研究了场-温度相图中的临界涨落。连接一维和三维系统中观察到的行为,$T_1^{-1}$弛豫率显示出明显的峰值,并延伸至远高于奈尔温度$T_N$,表明存在强烈的二维Berezinskii-Kosterlitz-Thouless(BKT)型涨落。实验与理论BEC相边界的定量匹配验证了有效的XXZ模型。该研究通过QMC确定了本征BKT转变温度$T_{\mathrm{BKT}}$,揭示了几乎与场无关的$T_{\mathrm{BKT}}/T_N \approx 0.74$。弛豫率的标度分析显示出与二维普适性一致的临界指数,并识别出一个二维物理占主导的窄温度窗口。这些发现确立了Ba$_2$CuSi$_2$O$_6$Cl$_2$作为探索量子磁体中BKT动力学的模型系统。

英文摘要

We study the spin dynamics in the quasi-2D spin-$1/2$ dimer compound Ba$_2$CuSi$_2$O$_6$Cl$_2$, which exhibits a magnetic field-induced Bose-Einstein condensate (BEC) of triplons. Using nuclear magnetic resonance spin-lattice relaxation rate ($T_1^{-1}$) measurements combined with large-scale quantum Monte Carlo (QMC) simulations, we investigate critical fluctuations across the field-temperature phase diagram. Bridging the behavior observed in 1D and 3D systems, the $T_1^{-1}$ relaxation rate shows a pronounced peak extending well above the Néel temperature $T_N$, indicating strong two-dimensional Berezinskii-Kosterlitz-Thouless (BKT)-type fluctuations. A quantitative match between experimental and theoretical BEC phase boundaries validates an effective XXZ model. The study determines the intrinsic BKT transition temperature $T_{\mathrm{BKT}}$ from QMC, revealing a nearly field-independent $T_{\mathrm{BKT}}/T_N \approx 0.74$. Scaling analysis of the relaxation rate shows critical exponents consistent with 2D universality, and a narrow temperature window is identified where 2D physics dominates. These findings establish Ba$_2$CuSi$_2$O$_6$Cl$_2$ as a model system for exploring BKT dynamics in quantum magnets.

2511.15592 2026-06-11 cs.CC 版本更新

On the Complexity of Bilevel Linear and Quadratic Programs in Fixed Dimensions

关于固定维数下双层线性与二次规划问题的复杂性

Sergey S. Ketkov, Oleg A. Prokopyev

AI总结 本文填补了双层线性规划在决策者变量或约束固定时的复杂性分类空白,证明悲观模型在跟随者变量固定时是强NP难的,而乐观模型多项式可解;同时发现线性与凸二次双层规划之间存在严格复杂性差距。

Comments The extended manuscript completes the complexity classification of bilevel linear programs (BLPs) in fixed dimensions and investigates whether the polynomial-time solvability results obtained for BLPs persist for bilevel quadratic programs (BQPs)

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AI中文摘要

众所周知,一般的双层线性规划(BLP)是强NP难的,即使领导者和跟随者的目标函数完全相反。然而,当其中一个决策者具有固定数量的变量或约束时,BLP的复杂性分类仍不完整。本文填补了这一复杂性图景中的剩余空白。因此,虽然乐观BLP在跟随者变量数量固定时已知是多项式可解的,但我们证明相应的悲观问题是强NP难的。据我们所知,这是第一个表明在可比假设下悲观公式可能比乐观公式计算上更困难的结果。此外,我们证明当跟随者约束数量固定时,BLP在乐观和悲观设置下都保持多项式可解。我们进一步研究了这些多项式时间可解性结果是否适用于双层凸二次规划。虽然乐观公式在跟随者变量数量固定时保持多项式可解,但我们证明跟随者约束数量固定的悲观公式变为NP难的。换句话说,除非P=NP,否则线性目标函数和凸二次目标函数的双层规划之间存在严格的复杂性差距。最后,我们表明将凸二次跟随者目标替换为非凸二次目标会使乐观问题变为NP难的,即使跟随者的两个维度都固定。

英文摘要

It is well-known that general bilevel linear programs (BLPs) are strongly $NP$-hard, even when the leader's and the follower's objective functions are exact opposites. However, the complexity classification of BLPs remains incomplete when one of the decision-makers has a fixed number of variables or constraints. In this paper, we close the remaining gap in this complexity landscape. Thus, while optimistic BLPs are known to be polynomially solvable when the number of follower variables is fixed, we prove that the corresponding pessimistic problem is strongly $NP$-hard. To the best of our knowledge, this is the first result demonstrating that, under comparable assumptions, the pessimistic formulation can be computationally harder than its optimistic counterpart. In addition, we prove that BLPs remain polynomially solvable in both the optimistic and the pessimistic settings when the number of follower constraints is fixed. We further investigate whether these polynomial-time solvability results persist for bilevel convex quadratic programs. While the optimistic formulation remains polynomially solvable when the number of follower variables is fixed, we prove that the pessimistic formulation with a fixed number of follower constraints becomes $NP$-hard. In other words, unless $P = NP$, there is a strict complexity gap between bilevel programs with linear and convex quadratic objective functions. Finally, we show that replacing a convex quadratic follower objective with a nonconvex quadratic one renders the optimistic problem $NP$-hard, even when both follower dimensions are fixed.

2511.15587 2026-06-11 math.AP math-ph math.MP 版本更新

On the optimal local well-posedness of the wave kinetic equation in $L^r$

关于波动力学方程在$L^r$中的最优局部适定性

Ioakeim Ampatzoglou, Tristan Léger

AI总结 本文在几乎临界的加权$L^r$空间($2 \leq r \leq \infty$)中统一处理波动力学方程的局部适定性,证明仅基于动力学工具,不依赖傅里叶理论。

Comments 26 pages

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Journal ref
J. Differential Equations 477, 114531 (2026)
AI中文摘要

在本文中,我们给出了波动力学方程在几乎临界的加权$L^r$空间($2 \leq r \leq \infty$)中局部适定性的统一处理。证明基于我们早期工作\cite{AmLe24, AmLemain25}的思想。我们的方法完全基于动力学工具,不涉及傅里叶理论。

英文摘要

In this paper, we give a unified treatment of the local well-posedness for the wave kinetic equation in almost critical weighted $L^r$ spaces with $2 \leq r \leq \infty.$ The proof builds on ideas from our earlier works \cite{AmLe24, AmLemain25}. Our approach is based solely on kinetic tools, with no appeal to Fourier theory.