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2606.08062 2026-06-09 eess.SY cs.CR cs.SY 新提交

Multidimensional Resilience for Electrical Power Systems: Systematic Review, Integrated Index, and Validation under Real-World Cyber-Physical Attack Scenarios

电力系统多维韧性:系统综述、综合指标及在网络物理攻击场景下的验证

Isaac Ortega Romero, Ioannis Zografopoulos

AI总结 本文通过PRISMA 2020综述识别五维韧性缺口,提出多维韧性指数(MDRI)以捕获耦合与放大效应,并在波兰网络攻击场景下验证,发现联合失效导致韧性损失比单维高46倍。

Comments 35 pages, Elsevier Renewable and Sustainable Energy Reviews

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AI中文摘要

能源系统加速脱碳已将电力系统转变为复杂基础设施,面临多种威胁,其相互作用产生传统韧性方法无法捕捉的系统脆弱性。尽管韧性评估已扩展到多个维度,现有研究大多孤立或成对考察这些维度,跨维度耦合尚未充分探索。本研究证明:i) 单维度评估无法捕捉同时发生的跨维度失效所产生的退化;ii) 当物理、运营和数字-网络维度共同受损时,出现非线性放大;iii) 气候和经济-监管压力因素加剧了这种放大。为此,我们采用混合定量方法。通过PRISMA 2020综述及前后向滚雪球方法,识别五个韧性维度(物理、运营、数字-网络、气候-外部和经济-监管)的方法论缺口和未解决的依赖关系。在此基础上,开发了多维韧性指数(MDRI)以捕获内源性耦合和外源性放大效应,并在2025年12月波兰能源基础设施网络攻击场景下进行验证。结果表明,级联和同时失效下的退化程度几乎是孤立应力下的八倍,而外源性条件使退化额外增加近六倍,其中72%的放大由外源性压力因素驱动。综合这些机制,与单向量参考相比,韧性损失增加了46倍。

英文摘要

The accelerating decarbonization of energy systems has transformed electrical power systems into complex infrastructures exposed to threats whose interactions generate systemic vulnerabilities that conventional resilience approaches fail to capture. Although resilience assessment has expanded across multiple dimensions, existing studies largely examine them in isolation or adjacent pairs, leaving cross-dimensional couplings insufficiently explored. This study demonstrates i) that single-dimension assessments fail to capture the degradation produced by simultaneous cross-dimensional failures, ii) the nonlinear amplification emerging when physical, operational, and digital-cyber dimensions are jointly compromised, and iii) the intensification imposed by climatic and economic-regulatory stressors. To this end, we leverage a hybrid quantitative methodology. A PRISMA 2020 review with backward and forward snowballing identifies methodological gaps and unresolved dependencies across five resilience dimensions: physical, operational, digital-cyber, climatic-external, and economic-regulatory. Following this analysis, a Multidimensional Resilience Index (MDRI) is developed to capture endogenous couplings and exogenous amplification effects and is validated under escalating cyber-physical attack scenarios inspired by the December 2025 attack on Polish energy infrastructure. Results show that degradation under cascading and simultaneous failures is nearly eight times greater than under isolated stress, while exogenous conditions amplify degradation by an additional factor approaching six, with 72% of this amplification driven by exogenous stressors. Combined, these mechanisms produce a 46-fold increase in resilience loss compared to a single-vector reference.

2606.08061 2026-06-09 math.CO math.SP 新提交

Cheeger-type inequalities for the second largest spectral gap from $1$ of the normalized Laplacian

关于归一化拉普拉斯算子的第二大谱间隙从 $1$ 开始的 Cheeger 型不等式

Lies Beers, Raffaella Mulas, Jan Petr

AI总结 研究图的归一化拉普拉斯算子第二大谱间隙,引入具有两步随机游走概率解释的新 Cheeger 型常数,并建立类似经典 Cheeger 不等式的尖锐不等式。

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AI中文摘要

我们研究图的归一化拉普拉斯算子的第二大谱间隙从 $1$ 开始,该量在文献中与随机游走、扩展图和 Ramanujan 图相关。我们将其与经典的 Cheeger 常数和对偶 Cheeger 常数联系起来,并引入一个新的 Cheeger 型常数,该常数在两步随机游走方面具有概率解释。对于这个常数,我们建立了类似于经典 Cheeger 不等式的尖锐不等式。

英文摘要

We study the second largest spectral gap from $1$ of the normalized Laplacian of a graph, a quantity that appears in the literature in connection with random walks, expander graphs, and Ramanujan graphs. We relate it to the classical Cheeger and dual Cheeger constants, and we introduce a new Cheeger-type constant admitting a probabilistic interpretation in terms of two-step random walks. For this constant, we establish sharp inequalities analogous to the classical Cheeger inequalities.

2606.08058 2026-06-09 math.CO 新提交

Determinant formulas for Ihara zeta functions via simple cycles

通过简单环路的 Ihara zeta 函数行列式公式

Kosei Watanabe

AI总结 基于迹幺半群代数框架,通过Cayley行列式建立有向图Ihara zeta函数的新行列式公式,并证明其倒数可表示为线图无回溯简单环数量的行列式。

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AI中文摘要

基于 Giscard 和 Rochet 引入的迹幺半群代数框架,我们为某些有向图的 Ihara zeta 函数建立了新的行列式公式。我们通过两个主要定理呈现结果。首先,在代数层面,我们展示了一个由 hike 幺半群环上的 Cayley 行列式表达的通用行列式公式,为几个已知的行列式表达式提供了统一视角。其次,通过自然环同态评估 hike 的长度,我们证明 Ihara zeta 函数的倒数可以显式地表示为一个行列式,其维度等于线图中无回溯简单环路的数量。

英文摘要

Building upon the algebraic framework of trace monoids introduced by Giscard and Rochet, we establish a new determinant formula for the Ihara zeta functions of certain digraphs. We present our results through two main theorems. First, at the algebraic level, we show a general determinant formula expressed by a Cayley determinant over the hike monoid ring, which provides a unifying perspective on several known determinant expressions. Second, by evaluating the lengths of hikes through a natural ring homomorphism, we prove that the reciprocal of the Ihara zeta function can be explicitly expressed as a determinant whose dimension is equal to the number of simple cycles of the line digraph without backtrack.

2606.08055 2026-06-09 math.AC 新提交

Weakly Q-ideals of commutative rings

交换环的弱Q-理想

Mahdi Anbarloei

AI总结 引入交换环中弱Q-理想的概念,研究其基本性质及与Q-理想的关系。

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AI中文摘要

本文引入并研究了交换环中弱Q-理想的概念。

英文摘要

In this paper, we introduce and study the notion of weakly Q-ideals in commutative rings.

2606.08054 2026-06-09 math.CO 新提交

A solution to Csikvári's conjecture and the largest matching root of $k$-graphs

Csikvári猜想及$k$-图的最大匹配根的解答

Jiang-Chao Wan, Yi Wang

AI总结 本文完全解决了Csikvári关于图的最大匹配根的猜想,并将其推广到一致超图,证明了边数为m的k-图的最大匹配根不超过m^{1/k},等号成立当且仅当图是相交的。

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AI中文摘要

2011年,Csikvári [Electron. J. Combin. {\bf 18} (2011), $\#$P182] 证明了在所有具有给定边数的图中,最大匹配根由阈值图达到,并猜想极值图应“尽可能像星”。本文对该问题给出了完整且肯定的回答,并将其推广到一致超图情形。我们证明:对于每个具有$m$条边的$k$-图$\mathcal{H}$,其最大匹配根满足 $$λ(\mathcal{H})\le m^{1/k},$$ 等号成立当且仅当$\mathcal{H}$是相交的。对于$k=2$,在删除所有孤立顶点后,所得图必为星$K_{1,m}$或三角形,从而证实了Csikvári猜想。此外,若匹配数$ν(\mathcal{H})\ge 2$,则 \[ λ(\mathcal{H})\le \left(\frac{m+\sqrt{m^2-4(ν(\mathcal{H})-1)}}{2}\right)^{1/k}, \] 等号成立当且仅当$ν(\mathcal{H})=2$且$\mathcal{H}$恰好有一个$2$-匹配。

英文摘要

In 2011, Csikvári [Electron. J. Combin. {\bf 18} (2011), $\#$P182] proved that among all graphs with a prescribed number of edges, the largest matching root is attained by a threshold graph, and conjectured that the extremal graph should be `as star-like as possible.' In this paper, we give a complete and affirmative answer to this problem and extend it to the setting of uniform hypergraphs. We prove that for every $k$-graph $\mathcal{H}$ with $m$ edges, its largest matching root satisfies $$λ(\mathcal{H})\le m^{1/k},$$ with equality if and only if $\mathcal{H}$ is intersecting. For $k=2$, after deleting all isolated vertices, the resulting graph must be the star $K_{1,m}$ or a triangle, thereby confirming Csikvári's conjecture. Moreover, if the matching number $ν(\mathcal{H})\ge 2$, then \[ λ(\mathcal{H})\le \left(\frac{m+\sqrt{m^2-4(ν(\mathcal{H})-1)}}{2}\right)^{1/k}, \] with equality if and only if $ν(\mathcal{H})=2$ and $\mathcal{H}$ has exactly one $2$-matching.

2606.08053 2026-06-09 quant-ph cs.NA math.NA 新提交

Numerical solution of the nonlinear Dirac equation by a splitting variational quantum algorithm

非线性狄拉克方程的数值求解:一种分裂变分量子算法

Qian Zuo, Ying He, Xiaofei Zhao

AI总结 提出分裂变分量子算法Dirac-sVQA,通过线性狄拉克子步和非线性变分修正分解非线性狄拉克方程,利用自旋-傅里叶传播器和测量基变分更新实现数值模拟。

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AI中文摘要

本文提出一种算子分裂变分量子算法,称为Dirac-sVQA,用于模拟非线性狄拉克方程(NLDE)。主要困难来自状态相关的非线性相互作用,其时间离散更新显式依赖于中间旋量态,通常无法实现为固定的状态无关酉电路。为解决这一困难,我们将NLDE演化分解为结构化的线性狄拉克子步和非线性变分修正。线性子步通过在联合位置-自旋寄存器上的自旋-傅里叶狄拉克传播子实现,保留了狄拉克算子的自旋-动量耦合和质量诱导的自旋演化。非线性修正被重新表述为基于测量的变分更新,通过少量重叠、自通道和交叉通道可观测量实现。我们提供了相应的量子电路,并推导了考虑测量的资源和复杂度估计。在多个非线性区域中的数值实验表明,Dirac-sVQA准确捕捉了总密度和分量旋量动力学,与经典傅里叶伪谱分裂解吻合良好,并随时间表现出稳定的误差行为。这些结果为非线性相对论波动方程的算子分裂变分量子模拟的可行性提供了数值证据。

英文摘要

In this work, we propose an operator-splitting variational quantum algorithm, termed Dirac-sVQA, for simulating the nonlinear Dirac equation (NLDE). The main difficulty arises from the state-dependent nonlinear interaction, its time-discrete update depends explicitly on the intermediate spinor state and, in general, cannot be implemented as a fixed state-independent unitary circuit. To address this difficulty, we decompose the NLDE evolution into a structured linear Dirac substep and a nonlinear variational correction. The linear substep is implemented by a spinor-Fourier Dirac propagator on a joint position-spin register, preserving the spin-momentum coupling and mass-induced spin evolution of the Dirac operator. The nonlinear correction is reformulated as a measurement-based variational update through a small set of overlap, self-channel, and cross-channel observables. We provide the corresponding quantum circuits and derive measurement-aware resource and complexity estimates. Numerical experiments in several nonlinear regimes show that Dirac-sVQA accurately captures both the total density and the componentwise spinor dynamics, agrees well with classical Fourier pseudospectral splitting solutions, and exhibits stable error behavior over time. These results provide numerical evidence for the feasibility of operator-splitting variational quantum simulation for nonlinear relativistic wave equations.

2606.08052 2026-06-09 physics.flu-dyn 新提交

Viscous spectral energy coupling across scales in generalised Newtonian fluids

广义牛顿流体中跨尺度的黏性能量谱耦合

Arthur Couteau, Panayotis Dimopoulos Eggenschwiler, Patrick Jenny

AI总结 通过直接数值模拟研究Carreau本构模型描述的广义牛顿流体湍流,发现变黏度项产生类似对流项的卷积耦合,在剪切增稠流体中形成近似反对称的偶极子结构,实现跨尺度能量传递,并导致耗散区出现幂律谱衰减。

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AI中文摘要

我们利用Carreau本构模型描述的广义牛顿流体的均匀各向同性湍流的直接数值模拟,研究了变黏度湍流的谱能量动力学,涵盖了剪切稀化和剪切增稠两种状态。变黏度Navier-Stokes系统的谱演化方程表明,黏性项变为非线性,并在谱空间中产生卷积积,形式上与对流项类似。与常黏度情况(黏性项作为纯局部耗散机制)不同,变黏度项在卷积积中同时包含保守(传递)和非保守(耗散)贡献。我们提出了黏性模式耦合$\hat{V}(\k, \kP)$的新计算,该耦合不满足类似于对流项的详细守恒性质。黏性耦合图揭示了两个不同的谱区域:$\kP \approx \bm{0}$附近的符号确定的非保守区域,以及剪切增稠流体中$\kP \approx \k$附近的类似传递的偶极子。该偶极子满足近似反对称性$\hat{V}(\k, \kP) \approx -\hat{V}(\kP, \k)$,这是保守能量传递的定义特征。这表明,跨尺度的能量传递(传统上完全归因于对流非线性)可以来自动量方程中的任何非线性项。黏性能量传递与对流传递一起参与正向级联,最终在耗散区取代后者。它的存在与剪切增稠流体中取代经典指数截止的幂律谱衰减的出现有关。

英文摘要

We investigate the spectral energy dynamics of turbulent flows with variable viscosity using direct numerical simulation of homogeneous isotropic turbulence of generalised Newtonian fluids described by the Carreau constitutive model, covering both shear-thinning and shear-thickening regimes. The spectral evolution equations for the variable viscosity Navier-Stokes system show that the viscous term becomes nonlinear and gives rise to a convolution product in spectral space, formally analogous to that of the convective term. Unlike the constant viscosity case, where it acts as a purely local dissipation mechanism, the variable viscosity term carries both conservative (transfer) and non-conservative (dissipation) contributions entangled in the convolution product. We present novel computations of the viscous \mtm coupling $\hat{V}(\k, \kP)$, which does not satisfy a detailed conservation property analogous to that of the convective term. The viscous coupling maps reveal two distinct spectral regions: a sign-definite non-conservative region near $\kP \approx \bm{0}$, and a transfer-like dipole near $\kP \approx \k$ in shear-thickening fluids. The dipole satisfies the approximate antisymmetry $\hat{V}(\k, \kP) \approx -\hat{V}(\kP, \k)$, which is the defining signature of a conservative energy transfer. This demonstrates that energy transfer across scales, a role traditionally attributed exclusively to the convective nonlinearity, can arise from any nonlinear term in the momentum equation. The viscous energy transfer participates in the forward cascade alongside the convective transfer, eventually taking over the latter in the dissipation range. Its presence is connected to the emergence of power-law spectral decay replacing the classical exponential cutoff in shear-thickening fluids.

2606.08050 2026-06-09 cs.HC 新提交

Automatic, Real-time Classification of User Feedback Using Large Language Models

使用大型语言模型自动实时分类用户反馈

Jim Maddock, Rose Leitner, Anna Wu

AI总结 本文介绍一个多年项目,利用大型语言模型自动分类用户反馈,降低时间与知识成本,使非技术用户也能实时访问评论、主题和分析,从而民主化数据分析过程。

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AI中文摘要

在本文中,我们讨论了一个正在进行的多年项目,该项目旨在通过自动化分类并提供对评论、主题和分析的实时访问,使开放文本反馈对用户体验从业者更易访问和有用。通过显著降低实施自动化解决方案的时间和知识成本,我们旨在有效民主化我们的数据分析过程,允许并鼓励非技术利益相关者自行访问和利用数据。我们分享了在此项目过程中遇到的组织和技术限制,以及由于这些限制而原型化的解决方案。

英文摘要

In this paper we discuss an ongoing multi-year project that aims to make open text feedback more accessible and useful to UX practitioners by automating classification and providing real time access to comments, themes, and analysis. By significantly lowering the time and knowledge cost of implementing automated solutions, we aim to effectively democratize our data analysis processes, allowing and encouraging non-technical stakeholders to access and leverage data on their own. We share both the organizational and technical constraints we have encountered over the course of this project, and the solutions we have prototyped as a result of those constraints.

2606.08047 2026-06-09 gr-qc 新提交

Warped Product Einstein Manifolds in Four Dimensions

四维翘曲乘积爱因斯坦流形

Jack C. M. Hughes, Joudy F. Jamal Beek, Fedor V. Kusmartsev

AI总结 本文通过曲率张量的手征6×6矩阵表示,对四维翘曲乘积流形进行爱因斯坦分类,并给出Petrov分类:3+1为I型,2+2为D型,1+3为O型。

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AI中文摘要

在四维(伪)黎曼流形$\mathcal{M}$上,曲率张量(视为2-形式上的自同态)允许一个手征$6 \times 6$矩阵表示,该表示分解为四个$3 \times 3$块。$\mathcal{M}$是爱因斯坦流形当且仅当非对角块为零。如果流形是翘曲乘积$\mathcal{M} = F \times_f B$,那么存在另一种矩阵表示,相对于将2-形式分解为由基和纤维上的外代数诱导的空间。这两种表示不是独立的,可以在它们之间找到相似变换。我们构造了这些矩阵以及$1+3$、$2+2$和$3+1$翘曲乘积的相关变换,从这一代数角度给出了爱因斯坦极限的分类。利用这一点,可以轻松地对每种情况下的爱因斯坦翘曲乘积进行Petrov分类:$3+1$通常是I型,$2+2$是D型,而$1+3$被限制为O型。在闭黎曼情况下,我们讨论了这些流形上的一些拓扑限制:在半共形平坦极限下,每个这样的爱因斯坦翘曲乘积必须是平坦的。

英文摘要

On four-dimensional (pseudo-)Riemannian manifolds $\mathcal{M}$ the curvature tensor (viewed as an endomorphism on 2-forms) admits a chiral $6 \times 6$ matrix representation which decomposes into four $3 \times 3$ blocks. $\mathcal{M}$ is Einstein if and only if the off-diagonal blocks vanish. If the manifold is a warped product $\mathcal{M} = F \times_f B$, then there exists an alternative matrix representation relative to the decomposition of the 2-forms into spaces induced by the exterior algebra on both the base and the fiber. These two representations are not independent and a similarity transformation can be found between them. We construct these matrices and associated transformations for $1+3$, $2+2$ and $3+1$ warped products, giving classifications for the Einstein limits from this algebraic perspective. Using this, one can easily Petrov classify the Einstein warped products for each case considered: $3+1$ are generically type-\RNum{1}, $2+2$ are type-D while $1+3$ are constrained to be type-O. In the closed Riemannian case, there are a number of topological restrictions on these manifolds that we discuss: in the half-conformally flat limit, each of these Einstein warped products must be flat.

2606.08045 2026-06-09 physics.optics physics.atom-ph physics.plasm-ph 新提交

40% boost in extreme ultraviolet conversion efficiency via simultaneous dual-beam 2-μm laser irradiation

通过同步双束2微米激光照射实现极紫外转换效率提升40%

Naoki Nagahama, Kaito Nishimiya, Shunya Yamamoto, Hayato Yazawa, Yuta Takai, Chisato Tanaka, Kazuyuki Sakaue, Atsushi Sunahara, Gerry O'Sullivan, Shinichi Namba, Takeshi Higashiguchi, Eiji J. Takahashi

AI总结 采用2090 nm Ho:YAG激光同步双束照射平面Sn靶,在相同总能量下将EUV转换效率从2.6%提升至3.6%,创下2微米驱动激光等离子体源的最高纪录,且等离子体条件基本不变。

Comments 4 pages, 5 figures,

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AI中文摘要

为下一代光刻技术提升极紫外(EUV)光源功率,需要在降低单脉冲能量的同时提高转换效率(CE)。我们通过使用2090 nm、20 ns的Ho:YAG激光同步双束照射平面Sn靶,实现了40%的CE增强。单束40 mJ照射的EUV CE为2.6%;将相同总能量等分为两束各20 mJ(峰值强度相同)后,EUV CE提升至3.6%,这是2微米驱动激光等离子体源中报道的最高值。两种配置下的EUV源尺寸(60-70 μm)和离子能谱几乎相同,证实了等离子体条件相当。由于该方案仅需被动分束,且易于扩展至三束或更多,它为高数值孔径和超数值孔径光刻提供了实现多千瓦级、节能型EUV源的实用途径。

英文摘要

Scaling extreme ultraviolet (EUV) source power for next-generation lithography demands higher conversion efficiency (CE) at reduced per-pulse energies. We demonstrated a 40% CE enhancement by simultaneous dual-beam irradiation of a planar Sn target with a 2090-nm, 20-ns Ho:YAG laser. Single-beam irradiation at 40 mJ yielded an EUV CE of 2.6%; splitting the same total energy equally into two beams of 20 mJ each - at identical peak intensity - raised the EUV CE to 3.6%, which was the highest reported for 2-μm-driven laser-produced plasma sources. The EUV source size (60-70 μm) and energetic-ion spectra were nearly identical across both configurations, confirming comparable plasma conditions. Because the scheme requires only passive beam splitting and scales readily to three or more beams, it offers a practical route toward multi-kW-class, energy-efficient EUV sources for high-NA and hyper-NA lithography.

2606.08042 2026-06-09 physics.ins-det 新提交

Overview of the ALICE ITS3 Upgrade

ALICE ITS3升级概述

Naseem Bouchhar

AI总结 ALICE将在LHC第三次停机期间用ITS3替换最内三层跟踪探测器,采用65nm CMOS工艺的弯曲单片有源像素传感器,实现无支撑结构、空气冷却,材料预算低于0.09%X$_0$每层。

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AI中文摘要

ALICE实验将在LHC第三次长期停机期间,用内部跟踪系统3(ITS3)替换其最内三层跟踪探测器。此次升级引入了首个全圆柱形、晶圆级硅顶点探测器,采用65nm CMOS工艺制造的单片有源像素传感器(MAPS)。通过将传感器减薄至50$μ$m并弯曲至小至19mm的半径,设计实现了自支撑结构,消除了传统支撑材料。晶圆级拼接实现了27cm长的无缝传感器,集成了电源和信号分配,消除了有源体积内的柔性印刷电路。这些创新,加上从水冷到空气冷却的转变,将材料预算降低至每层低于0.09%X$_0$。研发计划已通过全尺寸原型(MOSS、MOST)验证,证明了拼接可行性、高产量和辐射硬度。工程模型证实了空气对流冷却的可行性,表明了有效的热管理和结构稳定性。本文总结了拼接传感器开发、机械集成以及通往最终鉴定模型的关键进展。

英文摘要

The ALICE experiment will replace its three innermost tracking layers with the Inner Tracking System 3 (ITS3) during LHC Long Shutdown 3. This upgrade introduces the first fully cylindrical, wafer-scale silicon vertex detector, utilising Monolithic Active Pixel Sensors (MAPS) fabricated in a 65nm CMOS process. By thinning sensors to 50$μ$m and bending them to radii as small as 19mm, the design achieves a self-supporting structure that eliminates traditional support material. Wafer-scale stitching enables 27cm-long seamless sensors with integrated power and signal distribution, removing the need for flexible printed circuits within the active volume. These innovations, combined with a move from water to air cooling, reduce the material budget to less than 0.09%X$_0$ per layer. The R&D program has been validated through full-scale prototypes (MOSS, MOST), which demonstrated stitching feasibility, high yield, and radiation hardness. Engineering models confirmed the feasibility of air-convection cooling, indicating effective thermal management and structural stability. This contribution summarises the key advances in stitched sensor development, mechanical integration, and the path toward the final qualification model.

2606.08040 2026-06-09 math.NT math.DS 新提交

A criterion for weighted uniform distribution along functions from a Hardy field

Hardy域中函数沿加权均匀分布的一个准则

Michael Reilly

AI总结 本文利用可和性理论方法,将Boshernitzan关于Hardy域函数模1均匀分布的经典准则推广到加权平均情形,并应用于函数f(x)=x^{3/2}得到区间内点的存在性。

Comments 19 pages

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AI中文摘要

Boshernitzan的一个经典定理指出:若$f$属于Hardy域且对某个$\ell\in \mathbb{N}$满足$|f(x)|\prec x^{\ell}$,则序列$(f(n))_{n\in \mathbb{N}}$模1均匀分布当且仅当对所有$p(x)\in \mathbb{Q}[x]$有$\lim_{x\to\infty}\frac{|f(x)-p(x)|}{\log(x)} = \infty$。我们利用可和性理论方法给出了该结果的一个新证明,并通过获得$f$关于一大类加权平均模1均匀分布的充要条件,推广了Boshernitzan准则。作为我们结果的一个应用,我们证明:对函数$f(x) = x^{3/2}$,任意$(a,b)\subset [0,1]$和所有充分大的$N\in\mathbb{N}$,存在$n\in [N-N^{\frac{1}{4}},N]$使得$f(n)\mod 1\in (a,b)$。

英文摘要

A classical theorem of Boshernitzan states that if $f$ is a function which belongs to a Hardy field and which satisfies $|f(x)|\prec x^{\ell}$ for some $\ell\in \mathbb{N}$, then the sequence $(f(n))_{n\in \mathbb{N}}$ is uniformly distributed modulo 1 if and only if $\lim_{x\to\infty}\frac{|f(x)-p(x)|}{\log(x)} = \infty$ for all $p(x)\in \mathbb{Q}[x]$. We provide a new proof of this result using methods from summability theory and we extend Boshernitzan's criterion by obtaining necessary and sufficient conditions for $f$ to be uniformly distributed modulo 1 with respect to a broad class of weighted averages. As an application of our results, we show that for the function $f(x) = x^{3/2}$ and for any $(a,b)\subset [0,1]$, and all sufficiently large $N\in\mathbb{N}$, there is an $n\in [N-N^{\frac{1}{4}},N]$ such that $f(n)\mod 1\in (a,b)$.

2606.08024 2026-06-09 math.NT 新提交

Monogenity of Fibonacci polynomials and Lucas polynomials

Fibonacci多项式和Lucas多项式的单生成性

Han Chen, Weizhe Guo, Haojie Hong

AI总结 研究Fibonacci多项式F_n(x)和Lucas多项式L_n(x)的不可约因子的单生成性,证明对所有奇数n,F_n(x)的不可约因子是单生成的;对所有偶数n,L_n(x)的不可约因子是单生成的。

Comments Comments are welecome!

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AI中文摘要

我们研究了Fibonacci多项式$F_n(x)$和Lucas多项式$L_n(x)$的不可约因子的单生成性。我们的主要结果表明,对于每个奇数正整数$n$,$F_n(x)$的所有不可约因子都是单生成的,并且对于每个偶数正整数$n$,$L_n(x)$的所有不可约因子都是单生成的。

英文摘要

We investigate the monogenity of irreducible factors of the Fibonacci polynomials $F_n(x)$ and the Lucas polynomials $L_n(x)$. Our main results show that for every odd positive integer $n$, all irreducible factors of $F_n(x)$ are monogenic, and for every even positive integer $n$, all irreducible factors of $L_n(x)$ are monogenic.

2606.08023 2026-06-09 astro-ph.HE 新提交

Isolated neutron star candidates from the fourth generation XMM-Newton catalogues

来自第四代XMM-Newton星表的孤立中子星候选体

Adriana M. Pires, Christian Motch, Jan Kurpas, Axel D. Schwope, Baoda Li, Dejiang Yin, Li Ji, Jianzhong Liu, Lei Qian, Iris Traulsen, Liyun Zhang, Zhongli Zhang

AI总结 利用XMM-Newton超过20年的观测数据,通过软X射线谱和无光学对应体筛选出10个源,其中5个是令人信服的孤立中子星候选体,其软X射线辐射与遥远XINS一致,并通过种群合成模型验证了观测样本的合理性。

Comments 20 pages, 8 figures, A&A accepted

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AI中文摘要

X射线热辐射孤立中子星(XINSs)是一个稀有的种群,为了解中子星冷却、磁场演化和银河系人口分布提供了见解。利用欧洲空间局XMM-Newton天文台超过二十年的观测,我们在4XMM-DR9和4XMM-DR12星表中搜索了0.5–1 keV能段流量低至$10^{-14}$ erg cm$^{-2}$ s$^{-1}$的吸收XINS候选体。候选体基于软X射线谱以及缺乏已编录的光学、紫外或红外对应体进行选择。XMM-Newton和FAST的后续观测辅以SRG/eROSITA全天巡天、Chandra和光学巡天的数据。在分析的十个源中,五个是令人信服的XINS候选体,一个是已知的XINS 4XMM J022141.5-735632,两个是河外污染源,另外两个由于光子统计有限而仍然模糊。五个候选体表现出软($kT\sim80-100$ eV)、中等吸收且稳定的X射线辐射,与遥远的XINS一致。它们主要位于银道面,可能分别与约1.8和约6 kpc的距离有关。种群合成模拟预测在4XMM-DR12覆盖范围内有$20\pm5$个XINS,其中$6^{+2}_{-3}$个超过我们的流量阈值,如果额外的候选体得到确认,则与观测样本一致。模型进一步预测约70%的种群仍低于探测阈值。需要深层光学和额外的X射线观测来确定这些候选体的性质。未来的任务如NewAthena将能够对这些遥远种群进行更详细的研究,并改进对银河系XINS种群的约束。

英文摘要

X-ray thermally emitting isolated neutron stars (XINSs) are a rare population that provides insights into neutron star cooling, magnetic-field evolution, and Galactic demographics. Using more than two decades of observations from the European Space Agency's XMM-Newton Observatory, we searched the 4XMM-DR9 and 4XMM-DR12 catalogues for absorbed XINS candidates down to a flux of $10^{-14}$ erg cm$^{-2}$ s$^{-1}$ in the 0.5--1 keV band. Candidates were selected based on soft X-ray spectra and the absence of catalogued optical, ultraviolet, or infrared counterparts. Follow-up observations with XMM-Newton and FAST were complemented by data from the SRG/eROSITA All-Sky Survey, Chandra, and optical surveys. Of ten sources analysed, five are compelling XINS candidates, one is the known XINS 4XMM J022141.5-735632, two are extragalactic contaminants, and two remain ambiguous because of limited photon statistics. The five candidates exhibit soft ($kT\sim80-100$ eV), moderately absorbed, and stable X-ray emission consistent with distant XINSs. They are located primarily in the Galactic plane, with possible associations at distances of $\sim$1.8 and $\sim$6 kpc. Population-synthesis simulations predict $20\pm5$ XINSs within the 4XMM-DR12 footprint, of which $6^{+2}_{-3}$ exceed our flux threshold, consistent with the observed sample if additional candidates are confirmed. The model further predicts that $\sim$70% of the population remains below the detection threshold. Deep optical and additional X-ray observations are required to establish the nature of the candidates. Future missions such as NewAthena will enable more detailed studies of these distant populations and improve constraints on the Galactic XINS population.

2606.08022 2026-06-09 gr-qc 新提交

Degenerate Geometries as Matter-Free Physical Configurations in General Relativity: Three Examples

退化几何作为广义相对论中无物质物理构型:三个例子

Juri Dimaschko

AI总结 通过分支坐标变换构造三种具有虫洞拓扑的退化时空构型,在爱因斯坦-帕拉蒂尼-嘉当框架下证明它们无物质,并表明退化几何构成广义相对论构型空间的独立部分。

Comments The paper has been accepted for publlication in International Journal of Geometric Methods in Modern Physics

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AI中文摘要

我们研究了三种具有虫洞拓扑的退化时空构型,这些构型是通过对Rindler、Minkowski和Schwarzschild真空度规进行分支坐标变换得到的。这些构型分别是具有平面喉部的Rindler虫洞,以及具有球形喉部的Klinkhamer和Schwarzschild-Klinkhamer虫洞。在爱因斯坦-帕拉蒂尼-嘉当框架下,我们证明了这些退化构型是无物质的。在这方面,它们与薄壳模型中的非退化虫洞对应物有根本区别,后者需要奇异物质。然而,这里考虑的退化构型表现出不同的物理表现,从纯拓扑结构到真正的引力效应。此外,在所有三个例子中,我们证明了从非退化时空到无物质退化构型不存在极限过渡。这表明退化几何构成了广义相对论构型空间的一个独立部分。

英文摘要

We examine three degenerate spacetime configurations with wormhole topology, obtained via branching coordinate transformations of the Rindler, Minkowski, and Schwarzschild vacuum metrics.These configurations are, respectively, a Rindler wormhole with a planar throat, and the Klinkhamer and Schwarzschild Klinkhamer wormholes with spherical throats. Within the framework of the Einstein Palatini Cartan formulation, we demonstrate that these degenerate configurations are matter free. In this regard, they differ fundamentally from their nondegenerate wormhole counterparts in the thin shell model, which require exotic matter. Nevertheless, the degenerate configurations considered here exhibit distinct physical manifestations, ranging from purely topological structures to genuine gravitational effects. Furthermore, in all three examples, we demonstrate the absence of a limiting transition from the non-degenerate spacetime to the matter free degenerate configuration. This suggests that degenerate geometries constitute an independent sector of the configuration space of general relativity.

2606.08019 2026-06-09 cond-mat.str-el 新提交

Non-magnetic ground state in A$_2$WCl$_6$ (A = Cs, Rb, K): A face-centered cubic system of spin-orbit-entangled $J$ = 2 states

A$_2$WCl$_6$ (A = Cs, Rb, K) 中的非磁基态:自旋-轨道纠缠 $J$ = 2 态的面心立方体系

T. Takayama, K. Ishii, S. Bette, J. Nuss, Y. Matsumoto, K. Fürsich, M. Minola, D. P. Sari, I. Watanabe, A. Krajewska, R. Dinnebier, B. Keimer, H. Takagi

AI总结 研究反萤石型氯化钨A₂WCl₆(A=Cs,Rb,K)中W⁴⁺离子的5d²组态产生的自旋-轨道纠缠J=2态,发现K₂WCl₆经历立方到四方结构相变导致非磁单重态基态,而Rb₂WCl₆和Cs₂WCl₆保持非磁态,结构畸变源于局域四极分量但阻挫和化学无序抑制长程四极序。

Comments 8 figures

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AI中文摘要

具有强自旋-轨道耦合的重过渡金属化合物为 $d$ 电子多极物理提供了平台。我们报道了反萤石型氯化钨 A$_2$WCl$_6$ (A = Cs, Rb, K) 的电子、磁性和结构性质,该体系包含 W$^{4+}$ 离子的面心立方晶格。立方环境中 W$^{4+}$ 离子的 5$d^2$ 组态产生自旋-轨道纠缠的 $J$ = 2 态,该态被认为会引发多极序,如电荷四极序或磁八极序。我们发现 K$_2$WCl$_6$ 经历立方到四方的结构相变,该相变解除了 $J$ = 2 态的简并,导致非磁单重态基态。相比之下,Rb$_2$WCl$_6$ 和 Cs$_2$WCl$_6$ 没有显示相变迹象,并在最低测量温度下保持非磁态。在低温下,观察到微弱结构异常的迹象,这可能指向 WCl$_6$ 八面体局域畸变的存在。我们认为,微妙的结构畸变源于 $J$ = 2 态的局域四极分量,但阻挫的四极相互作用以及化学无序抑制了长程四极序的形成。

英文摘要

Heavy transition metal compounds with strong spin-orbit coupling appeared as a platform for $d$-electron multipolar physics. We report the electronic, magnetic, and structural properties of antifluorite-type tungsten chloride A$_2$WCl$_6$ (A = Cs, Rb, and K), comprising a face-centered cubic lattice of W$^{4+}$ ions. The 5$d^2$ configuration of W$^{4+}$ ions in a cubic environment yields a spin-orbit-entangled $J$ = 2 state, which has been discussed to give rise to multipolar ordering such as charge quadrupolar or magnetic octupolar ordering. We found that K$_2$WCl$_6$ undergoes a cubic-to-tetragonal structural transition which lifts the degeneracy of the $J$ = 2 state, leading to a non-magnetic singlet ground state. By contrast, Rb$_2$WCl$_6$ and Cs$_2$WCl$_6$ show no signs of phase transition and remain non-magnetic down to the lowest temperature measured. At low temperatures, signatures of weak structural anomalies were revealed, which may point to the presence of local distortions of the WCl$_6$ octahedra. We argue that the subtle structural distortion arises from the local quadrupolar component of the $J$ = 2 state but the frustrated quadrupolar interaction, together with chemical disorder, inhibits the formation of long-range quadrupolar ordering.

2606.08017 2026-06-09 cs.IT math.IT 新提交

Fluid Antenna System-Enabled Mitigation of Asynchronous Reception in Cell-Free Massive MIMO Systems

流体天线系统在无蜂窝大规模MIMO系统中缓解异步接收的影响

Jun Qian, Zan Li, Junhui Rao, Ross Murch, Khaled B. Letaief

AI总结 提出在分布式无蜂窝大规模MIMO系统中集成流体天线系统(FAS),利用其可重构空间位置释放额外空间自由度,通过联合优化天线位置和功率控制系数,有效缓解异步接收导致的性能下降。

Comments 13 pages, 6 figures. This work has been submitted to the IEEE for possible publication

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AI中文摘要

实际的分布式部署固有地遭受异步信号到达的影响,这加剧了多用户干扰并降低了系统性能,特别是对于相干传输。为了从本质上缓解异步接收效应,本文提出将流体天线系统(FAS)集成到分布式无蜂窝大规模MIMO系统中,利用其可重构的空间位置释放额外的空间自由度(DoFs)。我们建立了具有异步接收(即延迟相位)的FAS数据传输模型。我们还推导了所提出系统在相干和非相干传输下的下行链路频谱效率(SE)分析性能,使用低复杂度的最大比(MR)预编码来提供基本理论界限。具体地,我们提出了一种新颖的非单调加速投影梯度上升算法,联合优化FAS位置和功率控制系数,最大化下行链路总SE。数值结果表明,虽然异步接收严重降低了相干传输的系统性能,但通过优化FAS位置解锁的空间DoFs以及有效的功率控制,可以显著抵消未知延迟相位的影响,并优于传统的固定位置天线。对于本质上绕过异步接收的非相干传输,FAS的应用利用空间可重构性从本质上最大化信号强度,并实现更显著的SE增益。最终,我们提出的FAS系统结合有效的功率控制,减轻了由于异步接收导致的性能下降,并优于传统的固定位置天线,为FAS在稳健、高效的6G无蜂窝大规模MIMO系统中的实际部署铺平了道路。

英文摘要

Practical distributed deployments inherently suffer from asynchronous signal arrivals, which exacerbate multi-user interference and degrade system performance, especially for coherent transmission. To natively mitigate the asynchronous reception effect, this paper proposes integrating fluid antenna systems (FASs) into distributed cell-free massive MIMO systems, exploiting their reconfigurable spatial positions to release additional spatial degrees of freedom (DoFs). We establish the FAS-enabled data transmission model with asynchronous reception, i.e., delay phases. We also derive the analytical downlink spectral efficiency (SE) performance of the proposed system under coherent and non-coherent transmissions, using low-complexity Maximum Ratio (MR) precoding to provide fundamental theoretical bounds. Specifically, we propose a novel nonmonotone accelerated projected gradient ascent algorithm to jointly optimize FAS positions and power control coefficients, maximizing the downlink sum SE. Numerical results demonstrate that while asynchronous reception severely degrades system performance for coherent transmission, the spatial DoFs unlocked by optimized FAS positions, along with efficient power control, can significantly counteract the effects of unknown delay phases and outperform traditional fixed-position antennas. For non-coherent transmission, which inherently bypasses asynchronous reception, the application of FAS leverages spatial reconfigurability to natively maximize signal strength and achieve more pronounced SE gains. Ultimately, our proposed FAS-enabled system, coupled with efficient power control, mitigates performance degradation due to asynchronous reception and outperforms traditional fixed-position antennas, paving the way for the practical deployment of FASs in robust, highly efficient 6G cell-free massive MIMO systems.

2606.08012 2026-06-09 cs.CR 新提交

The Dodona Protocol: A Living Design Science Experiment in Oracle Design

Dodona协议:预言机设计中的活的设计科学实验

Giulio Caldarelli

AI总结 针对区块链预言机问题,受古代和现代预言机程序模式启发,提出模块化、链无关的Dodona协议,实现结构化咨询、访问控制、可归责解析等原则,并作为设计科学研究中的活实验。

Comments 20 pages, 3 figures, 3 tables. Reference implementation deployed on Ethereum Sepolia testnet; contract at https://sepolia.etherscan.io/address/0x43259D9A08b13aF95d2dcdCfc9a241CBD2855bB1

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AI中文摘要

预言机问题,广义上理解为将外部信息可靠地纳入基于区块链的系统的困难,已被学者和实践者广泛研究。最近的比较研究表明,现代区块链预言机的若干挑战,包括可归责性、问责性、完整性和查询设计,反映了古代预言机构(如德尔斐神谕)中已存在的程序和认知约束。然而,将这些见解转化为应用的预言机设计仍基本未探索。本文介绍了Dodona协议,这是一个受古代和现代预言机系统中识别出的程序模式启发的模块化、链无关的预言机服务。该协议以古希腊最古老的预言圣地之一——多多纳的宙斯神谕命名,将结构化咨询、访问控制、可归责解析、受限查询格式、声誉问责和分层服务可用性等原则操作化。其第一个模块实现了一个查询和争议解决机制,其中指定的专家解析者为请愿者提交的结构化问题提供具有约束力的答案。该预言机不声称揭示客观真理;相反,它产生各方事先同意接受的结果。本文介绍了Dodona协议的设计原理、架构和比较定位。它将该协议框架为设计科学研究传统中的一个活的研究实验,其中部署的系统作为研究工件,操作数据支持结构化分析、迭代改进和同行评审的传播。通过这样做,本文旨在弥合预言机理论与预言机实践之间的差距。

英文摘要

The oracle problem, broadly understood as the difficulty of reliably incorporating external information into blockchain-based systems, has been widely examined by scholars and practitioners. Recent comparative research has shown that several challenges of modern blockchain oracles, including attributability, accountability, integrity, and query design, mirror procedural and epistemic constraints already present in ancient oracular institutions such as the Delphic Oracle. Yet the translation of these insights into applied oracle design remains largely unexplored. This paper introduces the Dodona Protocol, a modular, chain-agnostic oracle service inspired by procedural patterns identified in ancient and modern oracle systems. Named after the Oracle of Zeus at Dodona, one of the oldest oracular sanctuaries in ancient Greece, the protocol operationalizes principles such as structured consultation, access control, attributable resolution, constrained query formats, reputational accountability, and tiered service availability. Its first module implements a query and dispute resolution mechanism in which a named expert resolver provides binding answers to structured questions submitted by petitioners. The oracle does not claim to reveal objective truth; rather, it produces outcomes that parties have agreed in advance to accept. The paper presents the design rationale, architecture, and comparative positioning of the Dodona Protocol. It frames the protocol as a living research experiment within the Design Science Research tradition, where the deployed system functions as the research artifact and operational data support structured analysis, iterative refinement, and peer-reviewed dissemination. In doing so, the paper seeks to bridge the gap between oracle theory and oracle practice.

2606.08010 2026-06-09 cond-mat.mes-hall 新提交

DC conductivity of tilted Dirac Fermions across the Lifshitz Transition: short- versus long-range impurities

Lifshitz转变下倾斜狄拉克费米子的直流电导率:短程与长程杂质

Mohammad H. Pakzamir, Zahra Faraei, Ali G. Moghaddam

AI总结 利用Kubo形式主义,研究二维倾斜狄拉克系统中短程和长程杂质散射对直流电导率的影响,发现Lifshitz转变处两种杂质导致截然不同的输运特征,并揭示极端输运各向异性。

Comments 17 pages, 10 figures

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AI中文摘要

我们理论研究了受短程和长程杂质散射的二维倾斜狄拉克系统的直流电导率。利用Kubo形式主义,我们系统地研究了亚临界(I型)、临界和过临界(II型)倾斜区域的输运。在亚临界相中,短程杂质产生频率无关的电导率,随倾斜单调减小。相反,长程库仑散射导致强能量依赖的电导率,由与倾斜无关的散射率控制。在Lifshitz转变($t = 1$)处,这些杂质的输运特征根本不同:态密度的van Hove奇点导致短程无序的局域电导率下降,但库仑杂质出现明显的宏观峰。在过临界区域,需要紫外动量截断来正则化开放费米面,导致每种杂质类型的不同行为。值得注意的是,垂直于倾斜方向的电导率($σ_{xx}$)对于短程缺陷在$t = \sqrt{2}$附近表现出截断依赖的非单调峰,而对于长程散射则随倾斜增加单调衰减。对于两种势,沿倾斜轴的电导率($σ_{yy}$)无界增加,揭示出极端的输运各向异性。对于长程杂质,电导率的能量依赖性在I型和II型中分别接近二次和线性。此外,在Lifshitz转变处,两种杂质类型的顶点修正都消失。最后,我们为这些现象提供了统一的几何框架,将倾斜参数确立为在狄拉克材料中工程化宏观输运的有力旋钮。

英文摘要

We theoretically investigate the DC conductivity of two-dimensional tilted Dirac systems subject to short- and long-range impurity scattering. Using the Kubo formalism, we systematically study transport across the subcritical (Type I), critical, and overcritical (Type II) tilt regimes. In the subcritical phase, short-range impurities yield a frequency-independent conductivity that decreases monotonically with tilt. Conversely, long-range Coulomb scattering results in a strongly energy-dependent conductivity governed by a tilt-independent scattering rate. At the Lifshitz transition ($t = 1$), the transport signatures of these impurities diverge fundamentally: the van Hove singularity in the density of states induces a localized conductivity dip for short-range disorder, but a pronounced macroscopic peak for Coulomb impurities. In the overcritical regime, an ultraviolet momentum cutoff is required to regularize the open Fermi surface, leading to distinct behaviors for each impurity type. Notably, the conductivity perpendicular to the tilt direction ($σ_{xx}$) exhibits a cutoff-dependent, non-monotonic peak near $t = \sqrt{2}$ for short-range defects, while it decays monotonically with increasing tilt for long-range scattering. For both potentials, the conductivity along the tilt axis ($σ_{yy}$) increases without bound, revealing extreme transport anisotropy. For long-range impurities, the energy dependence of the conductivity becomes nearly quadratic and linear for Type I and II, respectively. Furthermore, vertex corrections vanish identically at the Lifshitz transition for both impurity types. Finally, we provide a unified geometric framework for these phenomena, establishing the tilt parameter as a powerful knob for engineering macroscopic transport in Dirac materials.

2606.08009 2026-06-09 math.AC 新提交

On the Regularity of Dominant and Almost Complete Intersection Monomial Ideals

关于主导和几乎完全交单项式理想的正则性

Amir Mafi, Rando Rasul Qadir

AI总结 本文针对几乎完全交单项式理想给出了Castelnuovo-Mumford正则性的显式公式,并证明了主导理想和几乎完全交理想满足Küronya-Pintye猜想。

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AI中文摘要

设 $R = k[x_1,\ldots,x_n]$ 是域 $k$ 上 $n$ 个变量的多项式环,$I$ 是 $R$ 的单项式理想。如果 $I$ 是几乎完全交,则我们给出 $I$ 的 Castelnuovo-Mumford 正则性的显式公式,该公式用 $G(I)$ 中长度为 $|G(I)|-1$ 的正则序列中出现的支配变量的幂次表示,其中 $G(I)$ 是 $I$ 的极小单项式生成元集。此外,如果 $I$ 是主导理想或几乎完全交理想,则我们证明 $\operatorname{reg}(\overline{I}) \leq \operatorname{reg}(I)$,其中 $\overline{I}$ 表示 $I$ 的整闭包。这为这两类单项式理想提供了 Küronya-Pintye 猜想的肯定答案。另外,我们给出一些例子来阐明这些结果。

英文摘要

Let $R = k[x_1,\ldots,x_n]$ be a polynomial ring in $n$ variables over a field $k$, and let $I$ be a monomial ideal of $R$. If $I$ is an almost complete intersection, then we provide an explicit formula for the Castelnuovo-Mumford regularity of $I$ in terms of the powers of the dominant variables appearing in the regular sequence contained in $G(I)$ of length $|G(I)|-1$, where $G(I)$ is the set of minimal monomial generators of $I$. Furthermore, if $I$ is a dominant ideal or an almost complete intersection ideal, then we show that $\operatorname{reg}(\overline{I}) \leq \operatorname{reg}(I),$ where $\overline{I}$ denotes the integral closure of $I$. This provides a positive answer to the Küronya-Pintye conjecture for these two classes of monomial ideals. In addition, we give some examples to clarify these results.

2606.08007 2026-06-09 math.GR 新提交

On varieties where $\mathrm{CS}\mathfrak{X}$ implies $\mathfrak{X}\mathrm{T}$

关于满足 $\mathrm{CS}\mathfrak{X}$ 蕴含 $\mathfrak{X}\mathrm{T}$ 的簇

Omar Al-Raisi, Mohammad Shahryari

AI总结 本文研究满足CSX蕴含XT的群簇,给出新的簇实例,其中所有极大X-子群malnormal的群满足任意两个交非平凡的X-子群生成X-子群。

Comments 8 pages

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AI中文摘要

在之前的工作 \cite{Omar-Shah2} 中,我们开始了与固定簇 $\X$ 相关的 $\CSX$-群和 $\XT$-群的研究。一个群属于前者,如果它的所有极大 $\X$-子群都是 malnormal 的;属于后者,如果任意两个交非平凡的 $\X$-子群生成一个 $\X$-子群。一般来说,$\CSX$ 并不蕴含 $\XT$,然而如 \cite{Omar-Shah2} 所示,某些簇确实满足这一蕴含关系。在本文中,我们提供了另外一些满足 $\CSX$ 蕴含 $\XT$ 的簇的例子。

英文摘要

In our previous work \cite{Omar-Shah2}, we initiated the study of $\CSX$- and $\XT$-groups associated with a fixed variety $\X$. A group belongs to the former class if all of its maximal $\X$-subgroups are malnormal, and to the latter if any two $\X$-subgroups with nontrivial intersection generate an $\X$-subgroup. In general, $\CSX$ does not imply $\XT$, however as shown in \cite{Omar-Shah2}, some varieties do satisfy this implication. In this article, we provide additional examples of varieties for which $\CSX$ implies $\XT$.

2606.08005 2026-06-09 math.GT math.DS 新提交

Closed $4$--Manifolds Foliated by Hyperplanes

闭 $4$--流形被超平面叶状结构

José M. Espinar, Harold Rosenberg

AI总结 证明带有余维一叶状结构且叶为 $\mathbb{R}^3$ 的闭可定向 $4$--流形同胚于 $4$--环面 $\mathbb{T}^4$,若光滑结构允许光滑定义 $1$--形式则微分同胚。

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AI中文摘要

设 $M^4$ 是一个闭的、可定向的 $4$--流形,带有横截定向的 $C^2$ 余维一叶状结构,其叶微分同胚于 $\mathbb{R}^3$。我们证明 $M^4$ 同胚于 $4$--环面 $\mathbb{T}^4$。我们还证明,只要 $M$ 上的原始光滑结构允许光滑的定义 $1$--形式,结论加强为微分同胚 $M\cong\mathbb{T}^4$。

英文摘要

Let $M^4$ be a closed, orientable $4$--manifold carrying a transversely oriented $C^2$ codimension--one foliation whose leaves are diffeomorphic to $\mathbb{R}^3$. We prove that $M^4$ is homeomorphic to the $4$--torus $\mathbb{T}^4$. We also show that, whenever the original smooth structure on $M$ admits a smooth defining $1$--form, the conclusion sharpens to a diffeomorphism $M\cong\mathbb{T}^4$.

2606.08004 2026-06-09 cond-mat.stat-mech cond-mat.mtrl-sci 新提交

Tracking metastable phases by complex Lee-Yang zeros

通过复李-杨零点追踪亚稳相

Yi-Hua Dong, Ling Liu, Fang-Cheng Wang, Qi-Jun Ye, Xin-Zheng Li

AI总结 本文通过复李-杨零点(LYZs)在复热场平面中刻画亚稳相(MPs),并在可调态密度玩具模型和周期性驱动系统中数值验证,揭示了MP随参数增大而稳定化的机制,为相图分析和非平衡态调控提供新视角。

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AI中文摘要

亚稳相(MPs)是能量上不利的状态,通常在平衡相图中被抑制。我们证明,它们并非保持“隐藏”,而是存在于热场的复平面中,作为由李-杨零点(LYZs)界定的区域。我们在一个具有三个高斯峰的可调态密度玩具模型和一个更现实的周期性驱动系统中数值演示了这一点。在这两种情况下,随着人工参数或驱动幅度的增加,界定MP的LYZs接近实轴并分裂成独立的分支,标志着MP在相邻两个稳定相之间的扩大间隙中出现并稳定。在驱动系统中,LYZs的虚部与驱动强度相关,将李-杨理论与太赫兹物质操控联系起来。这些发现为相图分析中描述MPs提供了一种方案。通过将周期性驱动视为复热场,它也为理解和工程化非平衡集体态提供了新视角。

英文摘要

Metastable phases (MPs) are energetically unfavorable states typically suppressed in equilibrium phase diagrams. Rather than remaining ''hidden'', we show that they exist in the complex plane of thermal fields, as regions delineated by Lee-Yang zeros (LYZs). We demonstrate this numerically in a toy model with a tunable density of states featuring three Gaussian peaks and in a more realistic periodically driven system. In both cases, as artificial parameters or drive amplitudes increase, the LYZs bounding the MP approach the real axis and split into separated branches, signaling the emergence and stabilization of the MP within the enlarged gap between two adjacent stable phases. In the driven system, the imaginary part of LYZs correlates with drive strength, linking Lee-Yang theory to terahertz matter manipulation. These findings provide a scheme to describe MPs in phase diagram analysis. By viewing periodic drives as complex thermal fields, it also offers a new perspective for understanding and engineering non-equilibrium collective states.

2606.08003 2026-06-09 gr-qc astro-ph.CO hep-th 新提交

Does Eternal Inflation Violate the Smeared Null Energy Condition?

永恒暴胀是否违反涂抹零能条件?

Dong-Hui Yu, Yong Cai

AI总结 研究永恒暴胀中暴胀子的随机向上涨落是否违反涂抹零能条件(SNEC),通过Fokker-Planck方程和单轨迹分析表明,引力反作用在SNEC界限达到前已破坏背景时空假设,因此不违反SNEC。

Comments 6 pages

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AI中文摘要

涂抹零能条件(SNEC)对沿零测地线积累的负能量施加了半局部界限。在永恒暴胀中,暴胀子的罕见随机向上涨落会局部增加哈勃参数,从而与SNEC产生明显冲突。我们聚焦于一个典型的单场模型,研究这种量子诱导的自复制是否违反SNEC。利用Fokker-Planck方程,我们证明哈勃参数的系综漂移在参数上受到慢滚参数和半经典抑制的约束。此外,一个互补的单轨迹分析揭示了强时间尺度层次,$N_{\rm SNEC} \gg N_{\rm BR}$。这表明,即使对于罕见的向上随机涨落,在SNEC界限能被数学上接近之前,引力反作用早已使背景时空假设失效。我们得出结论:虽然标准随机扩散驱动永恒暴胀,但在半经典慢滚区域内,它本身并不会导致SNEC违反。

英文摘要

The smeared null energy condition (SNEC) imposes a semilocal bound on the negative energy accumulated along null geodesics. In eternal inflation, rare stochastic upward fluctuations of the inflaton locally increase the Hubble parameter, creating an apparent tension with the SNEC. Focusing on a canonical single-field model, we investigate whether this quantum-induced self-reproduction violates the SNEC. Using the Fokker-Planck equation, we demonstrate that the ensemble drift of the Hubble parameter is parametrically bounded by slow-roll parameters and semiclassical suppression. Furthermore, a complementary single-trajectory analysis reveals a strong timescale hierarchy, $N_{\rm SNEC} \gg N_{\rm BR}$. This indicates that even for rare upward stochastic excursions, gravitational backreaction invalidates the background spacetime assumption long before the SNEC bound can be mathematically approached. We conclude that while standard stochastic diffusion drives eternal inflation, it does not inherently lead to SNEC violations within the semiclassical slow-roll regime.

2606.07997 2026-06-09 math.DG 新提交

Diffeologies on Locally Convex Spaces and Smooth Multiplication of Distributions

局部凸空间上的微分同胚与分布的光滑乘法

Alireza Ahmadi, Bijan Davvaz, Jean-Pierre Magnot

AI总结 从微分同胚角度研究Hausdorff局部凸空间上的自然光滑结构,并应用于分布的非线性运算,给出Mackey完备性的几何刻画,构造微局域可乘分布空间并证明乘法光滑。

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AI中文摘要

我们从微分同胚的角度研究Hausdorff局部凸空间上的自然光滑结构及其在分布的非线性运算中的应用。我们证明一个Hausdorff局部凸空间是方便的当且仅当从该空间到其内部切空间的典范映射是同构,从而给出了Mackey完备性的几何刻画。我们还研究了这些微分同胚在完备化、对偶和归纳极限下的行为。作为应用,我们构造了微局域可乘分布空间作为波前集受限分布空间的微分同胚余极限,并证明诱导的到分布空间的乘法映射是光滑的。该构造仅使用标准的波前集乘法准则,并说明了微分同胚余极限如何编码部分定义的非线性运算的定义域。这为经典流形环境之外的Hörmander可容许乘法提供了一个微分同胚框架。

英文摘要

We study natural smooth structures on Hausdorff locally convex spaces from the point of view of diffeology and their application to nonlinear operations on distributions. We show that a Hausdorff locally convex space is convenient if and only if the canonical map from the space to its internal tangent space is an isomorphism, thereby giving a geometric characterization of Mackey completeness. We also examine the behavior of these diffeologies under completion, duality, and inductive limits. As an application, we construct the space of microlocally multipliable distributions as a diffeological colimit of wavefront-restricted distribution spaces and prove that the induced multiplication map into the space of distributions is smooth. The construction uses only the standard wavefront-set criterion for multiplication and illustrates how diffeological colimits encode domains of partially defined nonlinear operations. This yields a diffeological framework for Hörmander-admissible multiplication beyond the classical manifold setting.

2606.07994 2026-06-09 cs.DL stat.AP 新提交

The Rising Dominance of Methods Across Science

方法在科学中日益增长的主导地位

Alexander Krauss, Ariel Rosenfeld, Lutz Bornmann

AI总结 通过分析1980-2019年间超过300万篇论文,发现方法论文占比翻倍,标志着科学从1990年代初开始向方法驱动的结构性转变。

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AI中文摘要

科学进步传统上是通过理论见解和实验发现的相互作用来叙述的。然而,这种科学观低估了进步的第三个核心支柱:支撑概念进展和经验证据的方法。通过分析1980年至2019年间发表的超过300万篇科学文章,我们发现科学经历了一个根本性的结构转变。主要贡献新方法的论文(方法论文)的比例在过去四十年中翻了一番,在各个学科和引用影响水平上普遍上升。这种转变并非渐进演变,而是从1990年代初开始的一个关键转变,与计算革命和数据密集型科学的出现相一致。方法论研究的激增并不局限于被引用最多的精英出版物;它跨越了科学产出的全谱系。这些发现揭示了科学生态系统的系统性重新定向,其中可重复使用的方法日益成为科学进步的基本基础设施,挑战了理论和实验研究的传统二分法。随着科学变得越来越方法驱动,我们的结果呼吁重新思考如何评估、资助和组织研究——以更好地激励方法创新。尤其是在扩展人工智能必须与科学仪器有效集成以充分发挥其潜力的情况下,这一点尤为重要。

英文摘要

Scientific progress is traditionally narrated through the interplay of theoretical insights and experimental findings. Yet this view of science underplays a third and central pillar of progress: the methods that underlie both conceptual advances and empirical evidence. By analysing more than 3 million articles across science published between 1980 and 2019, we find that science has undergone a fundamental structural transition. The share of papers that primarily contribute new methods-methods papers-has doubled across science over the past four decades, rising universally across disciplines and citation impact levels. Rather than a gradual evolution, this transition marks a pivotal shift beginning in the early 1990s, aligning with the computational revolution and the emergence of data-intensive science. The surge in methodological research is not confined to the most cited, elite publications; it spans the full spectrum of scientific output. These findings reveal a systemic reorientation of the scientific ecosystem where reusable methods increasingly serve as the essential infrastructure of scientific advances, challenging the traditional dichotomy of theory and experimental research. As science becomes increasingly methods-driven, our results call for rethinking how research is evaluated, funded and organised-towards better incentivising method innovations. This is especially the case as expanding AI must be effectively integrated with scientific instruments to realise its full potential.

2606.07993 2026-06-09 math.AG 新提交

Tangential morphisms via log arithmetic geometry

通过对数算术几何的切向态射

Yuichiro Hoshi, Makoto Matsumoto, Chikara Nakayama

AI总结 本文利用对数几何重新表述了切向态射(Deligne切向基点的推广),给出了其对数几何解释。

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AI中文摘要

我们给出了切向态射(这是Deligne切向基点的推广)通过对数几何的重新表述。

英文摘要

We give a reformulation of tangential morphisms (which is a generalization of Deligne's tangential base point) via log geometry.

2606.07991 2026-06-09 physics.optics 新提交

General framework for incoherent topological structured light and optical information encoding

非相干拓扑结构光与光学信息编码的通用框架

Ao Zhou, Dong Xu, Yaning Zhou, Peng Li, Pujuan Ma, Xin Liu, Lin Liu, Jianlin Zhao, Zhigang Chen, Yangjian Cai, Chunhao Liang

AI总结 提出非相干Milnor多项式理论框架,实现拓扑与统计相干性独立调控,实验展示Hopf链环和三叶结相干奇点,并演示基于魔方旋转的光学信息编码方案。

Comments 26pages, 4 figures

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AI中文摘要

拓扑为描述物理系统中的全局不变量提供了强大的语言,然而光学拓扑主要在全相干光中研究。最近研究表明,非相干光可以承载由相干奇点介导的拓扑结构;然而,缺乏用于其构建和控制的通用框架。本文引入非相干Milnor多项式,建立了实空间非相干拓扑结构光的理论框架,其中拓扑和统计相干性作为独立且可联合寻址的自由度出现。该框架克服了相干拓扑结构光的基本限制,使得在不改变底层拓扑配置的情况下实现任意强度工程。实验上,我们实现了具有可编程统计相干性的非相干Hopf链环和三叶结相干奇点。我们进一步展示了一种受魔方旋转启发的鲁棒光学信息编码方案,其中统计相干性决定与魔方初始状态相关的远场强度图案,而拓扑结构控制作为加密密钥的受控旋转。我们的结果将非相干拓扑结构光从物理好奇心推进到可编程光子平台,为光学信息编码、统计光子学以及超越相干光学拓扑的相干工程功能开辟了新途径。

英文摘要

Topology provides a powerful language for describing global invariants in physical systems, yet optical topology has been explored predominantly with fully coherent light. Recent studies have shown that incoherent light can host topological structures mediated by coherence singularities; however, a general framework for their construction and control has been lacking. Here, we introduce an incoherent Milnor polynomial, which establishes a theoretical framework for real-space incoherent topological structured light, in which topology and statistical coherence emerge as independent and jointly addressable degrees of freedom. This framework overcomes a fundamental limitation of coherent topological structured light, enabling arbitrary intensity engineering without altering the underlying topological configuration. Experimentally, we realize incoherent Hopf-linked and trefoil-knotted coherence singularities with programmable statistical coherence. We further demonstrate a robust optical information-encoding scheme inspired by Rubik's-cube-like rotations, where statistical coherence determines far-field intensity patterns associated with the cube's initial states, and topological structures govern controlled rotations acting as encryption keys. Our results advance incoherent topological structured light from a physical curiosity to a programmable photonic platform, opening new avenues for optical information encoding, statistical photonics, and coherence-engineered functionalities beyond coherent optical topology.

2606.07990 2026-06-09 math.CO 新提交

On the distributions of the statistics (des, maj, inv) over several classes of permutations

关于几类排列上统计量(des, maj, inv)的分布

Guo-Niu Han, Kathy Q. Ji, Huan Xiong

AI总结 研究经典排列、第一类和第二类Andre排列以及Simsun排列上三元统计量(des, maj, inv)的联合分布,通过最小元素位置分解得到生成函数的显式递推关系。

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AI中文摘要

我们研究了经典排列、第一类和第二类Andre排列以及Simsun排列上三元统计量(des, maj, inv)的联合分布。通过根据最小元素的位置分解排列,我们得到了这些统计量生成函数的显式递推关系。在经典排列情形下,我们的递推关系给出了Gessel提出的三元统计量(des, maj, inv)的生成函数,该结果通常使用MacMahon技巧证明。

英文摘要

We investigate the joint distribution of the trivariate statistics (des, maj, inv) on classical permutations, Andre permutations of the first and second kinds, and Simsun permutations. By decomposing permutations according to the position of the smallest element, we obtain explicit recurrence relations for the generating functions of these statistics. In the classical permutation setting, our recurrence relation yields the generating function for the trivariate statistics (des, maj, inv) due to Gessel, which is typically proved using MacMahon's technique.

2606.07989 2026-06-09 astro-ph.SR astro-ph.IM 新提交

Sunrise III: Instrument, mission, data, and first results

Sunrise III:仪器、任务、数据及初步结果

Sami K. Solanki, H. N. Smitha, Andreas Lagg, Achim Gandorfer, Jose Carlos del Toro Iniesta, Yukio Katsukawa, Pietro Bernasconi, Thomas Berkefeld, Alex Feller, Tino L. Riethmüller, Alberto Álvarez-Herrero, Masahito Kubo, David Orozco Suárez, Bianca Grauf, Michael Carpenter, Alexander Bell, Valentín Martínez Pillet, Laurent Gizon, Francisco Javier Bailén, Julian Blanco Rodríguez, Juan Sebastián Castellanos Durán, Edvarda Harnes, Johannes Hoelken, Francisco A. Iglesias, Ryohtaroh T. Ishikawa, Yusuke Kawabata, Takuma Matsumoto, Takayoshi Oba, Kunal H. Singh, Azaymi L. Siu-Tapia, Hanna Strecker, Dusan Vukadinović, Michiel van Noort, Maria Balaguer Jiménez, Esteban Sanchis Kilders, Ignacio Torralbo, Christoph Kuckein, Hirohisa Hara, Toshifumi Shimizu, Reiner Volkmer, Tobias Preis, Nour E. Raouafi, Angelos Vourlidas, Johann Hirzberger, Werner Deutsch, Dietmar Germerott, Klaus Heerlein, Martin Kolleck, Daniel Álvarez García, Antonio C. López Jiménez, Luis R. Bellot Rubio, José Miguel Morales-Fernández, Antonio Jesús Moreno Mantas, Beatriz Aparicio del Moral, Antonio Sánchez Gómez, Eduardo Bailón Martínez, Pablo Santamarina Guerrero, David Hernández Expósito, Angel Tobaruela, José Luis Gasent Blesa, Erich Schulze, Harry Eaton, Geoffrey Palo, Daniel Ayoub, Yoshihiro Naito, Carlos Quintero Noda, Fumihiro Uraguchi, Toshihiro Tsuzuki, Javier Piqueras Carreño

AI总结 介绍平流层气球太阳观测站Sunrise III的仪器、飞行任务、数据采集及初步科学结果,涵盖1米望远镜、三个后焦点仪器和图像稳定系统,于2024年7月成功飞行6.5天,收集约200 TB数据。

Comments Introductory paper to the Focus Issue on Sunrise III in ApJL

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AI中文摘要

Sunrise III是一个平流层气球载太阳观测站,配备1米直径望远镜、三个后焦点仪器以及图像稳定系统,全部位于保护性吊舱内。它从太阳表面到中间色球层对低层太阳大气进行采样,分辨率接近太阳上50公里。Sunrise III于2024年7月成功飞行了6.5天,悬挂在从瑞典北部到加拿大西北部的零压平流层气球上,收集了约200 TB的数据。本期ApJL聚焦于此次飞行收集的数据的首批科学结果。本文介绍了这一焦点特刊,简要概述了仪器能力、飞行任务和收集的数据。还简要讨论了测量、数据缩减和解释方面的挑战。文章最后概述了从这些数据中获得的首批科学成果,如当前焦点特刊所示。

英文摘要

Sunrise III is a stratospheric balloon-borne solar observatory with a 1-m diameter telescope and three post-focus instruments, along with an image stabilisation system, all within a protective gondola. It samples the lower solar atmosphere, from the solar surface to the middle chromosphere, at a resolution approaching 50~km on the Sun. Sunrise III flew successfully for 6.5 days suspended from a zero-pressure stratospheric balloon from northern Sweden to north-western Canada in July 2024, gathering around 200 TB of data. The present issue of ApJL focuses on the first scientific results from the data collected during that flight. This paper introduces this Focus Issue, providing a very brief overview of the capabilities of the instrumentation, the flight and of the gathered data. Challenges for the measurements, data reduction and interpretation are also briefly touched upon. The paper ends with an overview of the first set of science results obtained from these data, as presented in the current Focus Issue.