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2411.06254 2026-06-03 cs.IR

EviRerank: Adaptive Evidence Construction for Long-Document LLM Reranking

EviRerank:面向长文档LLM重排序的自适应证据构建

Minghan Li, Eric Gaussier, Juntao Li, Guodong Zhou

AI总结 针对解码器-only LLM重排序长文档时推理成本高、相关信号被无关上下文稀释的问题,提出EviRerank框架,通过轻量选择器分块、自适应证据预算(AEB)和摘要增强(SA)构建紧凑证据上下文,再用LLM重排序,在多个基准上超越全文档重排序和强基线。

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AI中文摘要

仅解码器的大语言模型(LLM)在重排序长文档时面临挑战:推理成本高,且相关信号可能被无关上下文稀释。受诊断性注意力分析的启发(该分析表明附加的无关上下文会削弱以查询为中心的交互),我们提出了EviRerank,一种基于证据的、面向仅解码器LLM的长文档重排序框架。EviRerank首先使用轻量选择器(如BM25、双编码器或交叉编码器)对文档块进行评分。然后,通过自适应证据预算(AEB)动态分配证据块,并通过摘要增强(SA)添加紧凑的全局线索,在硬令牌上限下构建紧凑的重排序上下文。最后,使用仅解码器LLM对紧凑的证据上下文进行重排序。在TREC DL'19、DL'22、DL'23和MLDR-zh上,EviRerank在减少输入长度的同时,始终优于全文档LLM重排序和强块选择基线。RankZephyr-7B验证进一步证实了其可迁移至列表式重排序。在TREC DL'19上,EviRerank在使用紧凑证据上下文的情况下,nDCG@10达到0.744,MAP达到0.307,优于RankLLaMA。

英文摘要

Decoder-only LLM rerankers struggle with long documents: inference is costly and relevance signals can be diluted by irrelevant context. Motivated by a diagnostic attention analysis suggesting that appended irrelevant context can weaken query-focused interactions, we propose EviRerank, an evidence-based long-document reranking framework for decoder-only LLMs. EviRerank first scores document blocks with a lightweight selector, such as BM25, a bi-encoder, or a cross-encoder. It then constructs a compact reranking context under a hard token cap by dynamically budgeting evidence blocks with Adaptive Evidence Budgeting (AEB) and adding a compact global cue via Summary Augmentation (SA). Finally, the compact evidence context is reranked with a decoder-only LLM. Across TREC DL'19, DL'22, DL'23, and MLDR-zh, EviRerank consistently outperforms full-document LLM reranking and strong block-selection baselines while reducing input length. RankZephyr-7B validation further confirms transfer to listwise reranking. On TREC DL'19, EviRerank reaches up to 0.744 nDCG@10 and 0.307 MAP, improving over RankLLaMA while using a compact evidence context.

2601.02323 2026-06-03 math.GT

Crossing matrix and a polynomial invariant of braid systems up to Hurwitz equivalence

Crossing matrix and a polynomial invariant of braid systems up to Hurwitz equivalence

Ayaka Shimizu, Yoshiro Yaguchi

AI总结 研究辫子的交叉矩阵,引入一个在Hurwitz等价下不变的辫子系统多项式不变量,并应用于曲面辫子和曲面链接,定义了一个指示辫子系统之间是否需要欧拉融合或分裂的不变量。

Comments 20 pages, 7 figures

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AI中文摘要

我们研究辫子的交叉矩阵,并引入一个在Hurwitz等价下不变的辫子系统多项式不变量。作为对曲面辫子和曲面链接研究的应用,我们还定义了一个不变量,可用作指示辫子系统之间是否需要欧拉融合或分裂的指标。

英文摘要

We study the crossing matrix of a braid and introduce a polynomial invariant for braid systems that is invariant under Hurwitz equivalence. As an application to the study of surface braids and surface links, we also define an invariant that can be used as an indicator of the necessity of Euler fusion or fission between braid systems.

2601.01317 2026-06-03 cs.NE

Benchmarking Continuous Dynamic Multi-Objective Optimization: Survey and Generalized Test Suite

连续动态多目标优化基准测试:综述与广义测试套件

Chang Shao, Qi Zhao, Nana Pu, Shi Cheng, Jing Jiang, Yuhui Shi

AI总结 本文提出一个综合框架,通过广义帕累托最优集变化、变量贡献不平衡、动态旋转矩阵、时间扰动和广义时间链接机制,构建高真实性和挑战性的动态多目标优化基准测试,实验证明其优于传统基准。

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AI中文摘要

动态多目标优化领域引起了学术界和工业界的广泛兴趣,因为许多随时间演变的实际应用可以自然地表述为动态多目标优化问题。这种日益增长的需求因此需要先进的基准测试来严格评估优化算法在现实条件下的性能。本文介绍了一个全面且原则性的框架,用于构建高度真实且具有挑战性的动态多目标优化基准测试。所提出的框架包含几个新颖的组成部分,包括:允许帕累托最优集在超曲面上变化的广义公式;创建受控变量贡献不平衡以生成异质景观的机制;以及用于引起时变变量交互和非可分离性的动态旋转矩阵。此外,我们引入了一个时间扰动机制来模拟不规则的环境变化,并提出了一个广义时间链接机制,该系统地将历史解质量嵌入到未来问题中,从而捕捉关键的现实世界现象,如误差积累和时间欺骗。广泛的实验结果验证了所提出框架的有效性,展示了其在真实性、复杂性以及区分最先进算法性能方面优于传统基准测试。因此,这项工作为动态多目标优化基准测试建立了新标准,并为开发和评估能够应对现实动态系统复杂性的下一代算法提供了强大工具。

英文摘要

The field of Dynamic Multi-Objective Optimization (DMOO) has witnessed a surge of interest from both academia and industry, as numerous time-evolving real-world applications can be naturally formulated as Dynamic Multi-Objective Optimization Problems (DMOPs). This growing demand thus necessitates advanced benchmarks to rigorously evaluate optimization algorithms under realistic conditions. This paper introduces a comprehensive and principled framework for constructing highly realistic and challenging DMOO benchmarks. The proposed framework incorporates several novel components, including: a generalized formulation that allows the Pareto-optimal Set (PS) to change on hypersurfaces; a mechanism for creating controlled variable contribution imbalances to generate heterogeneous landscapes; and dynamic rotation matrices for inducing time-varying variable interactions and non-separability. Furthermore, we incorporate a temporal perturbation mechanism to simulate irregular environmental changes and propose a generalized time-linkage mechanism that systematically embeds historical solution quality into future problems, thereby capturing critical real-world phenomena such as error accumulation and time-deception. Extensive experimental results validate the effectiveness of the proposed framework, demonstrating its superiority over conventional benchmarks in terms of realism, complexity, and its capability for discriminating state-of-the-art algorithmic performance. Thus, this work establishes a new standard for dynamic multi-objective optimization benchmarking and provides a powerful tool for the development and evaluation of next-generation algorithms capable of addressing the complexities of real-world dynamic systems.

2601.01100 2026-06-03 cond-mat.supr-con cond-mat.mtrl-sci physics.comp-ph

Strain-triggered high-temperature superconducting transition in two-dimensional carbon allotrope

应变触发二维碳同素异形体中的高温超导转变

Tian Yan, Ru Zheng, Jin-Hua Sun, Fengjie Ma, Xun-Wang Yan, Miao Gao, Tian Cui, Zhong-Yi Lu

AI总结 通过第一性原理计算,发现对由三角形、六边形和八边形组成的二维碳同素异形体THO-石墨烯施加双轴拉伸应变可诱导超导转变,最高超导转变温度达45 K,为二维元素超导体设立了新纪录。

Comments 7 pages, 5 figures

Journal ref Front. Phys. 21, 125205 (2026)

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AI中文摘要

通过特定调制将非超导材料驱动到超导状态是超导领域的一个关键焦点。压力是一种强大的方法,可以使三维(3D)材料在非超导和超导状态之间切换。在二维(2D)情况下,应变工程起着与压力类似的作用。然而,纯应变诱导的二维系统超导性仍然极为罕见。使用第一性原理计算,我们证明了仅通过施加双轴拉伸应变,就可以在由三角形、六边形和八边形组成的二维碳同素异形体THO-石墨烯中诱导超导转变。自由状态的THO-石墨烯是非超导的。令人惊讶的是,应变THO-石墨烯中的电子-声子耦合被增强到足以配对电子并实现超导,最高超导转变温度达到45 K。这项工作不仅为仅通过应变控制二维系统中的金属-超导体转变提供了一个显著的例子,而且为二维元素超导体的超导转变温度设立了新纪录。

英文摘要

Driving non-superconducting materials into a superconducting state through specific modulation is a key focus in the field of superconductivity. Pressure is a powerful method that can switch a three-dimensional (3D) material between non-superconducting and superconducting states. In the two-dimensional (2D) case, strain engineering plays a similar role to pressure. However, purely strain-induced superconductivity in 2D systems remains exceedingly scarce. Using first-principles calculations, we demonstrate that a superconducting transition can be induced solely by applying biaxial tensile strain in a 2D carbon allotrope, THO-graphene, which is composed of triangles, hexagons, and octagons. Free-standing THO-graphene is non-superconducting. Surprisingly, the electron-phonon coupling in strained THO-graphene is enhanced strong enough to pair electrons and realize superconductivity, with the highest superconducting transition temperature reaching 45 K. This work not only provides a notable example of controlling metal-superconductor transition in 2D system just via strain, but also sets a new record of superconducting transition temperature for 2D elemental superconductors.

2411.15691 2026-06-03 stat.ME math.ST stat.TH

Semi-supervised inference using unlabeled summary statistics

使用无标签汇总统计的半监督推断

Facheng Yu, Zhen Qi, Yuqian Zhang

AI总结 提出在仅有无标签汇总统计(如样本均值和协方差)的受限半监督设置下,利用无标签汇总统计提高均值估计效率并校正选择偏差的方法,并扩展到平均处理效应估计。

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AI中文摘要

半监督推断假设可以访问一个标记数据集以及一个结果变量缺失的大型无标签数据集,它被广泛用于提高统计效率和支持跨人群的泛化能力。然而,在许多现代应用中,由于隐私限制、数据共享限制或存储约束,个体水平的无标签数据可能无法直接访问,而无标签人群的汇总统计量(如样本均值和协方差)通常是可用的。在这项工作中,我们研究了这种受限的半监督设置,其中除了具有个体观测的标记数据外,来自无标签人群的辅助信息仅通过汇总统计量可用。我们提出了在协变量独立和协变量依赖标记下用于均值估计的新半监督推断方法,并表明无标签汇总统计仍然可以提高效率并帮助校正选择偏差。所提出的方法适用于高维情况,并且对模型误设具有鲁棒性。在稀疏性条件下获得有效的推断,这些条件与假设可以访问个体水平无标签样本的半监督方法所需的条件相当。我们的方法依赖于一种专门的交叉拟合程序,其中样本分割仅应用于标记数据,这消除了对个体化无标签协变量的需求。我们进一步将该框架扩展到平均处理效应估计,从而在这种受限的半监督设置中实现因果结论的泛化性和可迁移性。

英文摘要

Semi-supervised inference assumes access to a labeled dataset together with a large unlabeled dataset in which the outcome variable is missing, and it is widely used to improve statistical efficiency and support generalizability across populations. In many modern applications, however, individual-level unlabeled data may not be directly accessible due to privacy restrictions, data-sharing limits, or storage constraints, while summary statistics such as sample means and covariances from the unlabeled population are often available. In this work, we study this constrained semi-supervised setting where, in addition to labeled data with individualized observations, auxiliary information from the unlabeled population is available only through summary statistics. We propose new semi-supervised inference methods for mean estimation under both covariate-independent and covariate-dependent labeling and show that unlabeled summaries can still improve efficiency and help correct selection bias. The proposed methods apply in high dimensions and are robust to model misspecification. Valid inference is obtained under sparsity conditions comparable to those required by semi-supervised methods that assume access to individual-level unlabeled samples. Our approach relies on a specialized cross-fitting procedure, where sample splitting is applied only to the labeled data, which removes the need for individualized unlabeled covariates. We further extend this framework to average treatment effect estimation, enabling generalizability and transportability of causal conclusions in this constrained semi-supervised setting.

2601.00704 2026-06-03 gr-qc astro-ph.CO hep-th

Exceptional Lines and Excitation of (Nearly) Double-Pole Quasinormal Modes: A Semi-Analytic Study in the Nariai Black Hole

异常线与(近)双极点准正则模式的激发:Nariai黑洞的半解析研究

Nao Nakamoto, Naritaka Oshita

AI总结 本文通过半解析方法研究Nariai极限下Kerr-de Sitter和Myers-Perry黑洞中质量标量场的准正则模式,发现异常线并分析其激发因子,探讨了双极点准正则模式的瞬态线性增长及其对早期环down稳定性的影响。

Comments 16 pages, 14 figures. Matches published version in PRD; minor citation corrections

Journal ref Phys. Rev. D 113, 104032 (2026)

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AI中文摘要

我们展示了Kerr-de Sitter和Myers-Perry黑洞中质量标量场的准正则模式(QNMs)表现出异常线(EL),这是参数空间中异常点(EPs)的连续集合,在该线上两个QNM频率及其相关解重合。我们发现异常线出现在由标量质量和黑洞自旋参数张成的参数空间中,也在Nariai极限下出现,即$r_{\rm c} - r_{\rm h} \to 0$,其中$r_{\rm c}$和$r_{\rm h}$分别表示宇宙视界和黑洞视界的半径。我们解析研究了异常线附近QNMs的振幅或激发因子。这种解析处理之所以可能,是因为在Nariai极限下,扰动方程简化为具有Pöschl-Teller(PT)势的波动方程。我们讨论了异常线上及附近QNMs的相消激发和环down的稳定性。QNMs的瞬态线性增长——异常点或异常线附近的一种特征激发模式——以及这种线性增长主导早期环down的条件,也被解析研究。我们的条件适用于涉及(近)双极点QNMs激发的一大类系统。

英文摘要

We show that quasinormal modes (QNMs) of a massive scalar field in Kerr-de Sitter and Myers-Perry black holes exhibit an exceptional line (EL), which is a continuous set of exceptional points (EPs) in parameter space, at which two QNM frequencies and their associated solutions coincide. We find that the EL appears in the parameter space spanned by the scalar mass and the black hole spin parameter, and also in the Nariai limit, i.e., $r_{\rm c} - r_{\rm h} \to 0$, where $r_{\rm c}$ and $r_{\rm h}$ denote the radii of the cosmological and black hole horizons, respectively. We analytically study the amplitudes or excitation factors of QNMs near the EL. Such an analytic treatment becomes possible since, in the Nariai limit, the perturbation equation reduces to a wave equation with the Pöschl-Teller (PT) potential. We discuss the destructive excitation of QNMs and the stability of the ringdown near and at the EL. The transient linear growth of QNMs -- a characteristic excitation pattern near an EP or EL -- together with the conditions under which this linear growth dominates the early ringdown, is also studied analytically. Our conditions apply to a broad class of systems that involve the excitation of (nearly) double-pole QNMs.

2512.24423 2026-06-03 quant-ph

A Quantum-Inspired Algorithm for Graph Isomorphism

一种受量子启发的图同构算法

Innes L. Maxwell, Stefan N. van den Hoven, Jelmer J. Renema

AI总结 本文提出一种基于高斯玻色采样的经典算法,通过分析量子采样系统的统计特性来检验图同构的必要条件,从而判断图对是否非同构。

Comments 12 pages

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AI中文摘要

我们当前所处的嘈杂中等规模量子(NISQ)技术时代以非通用性、易受错误和噪声影响以及寻找有用应用为特征。尽管在这个时代,实际量子优势的演示仍然难以实现,但它为开发和评估系统及其解决问题的能力提供了空间。在这项工作中,我们批判性地评估了一种针对图同构问题的量子算法,该算法在光子量子设备上实现。受该量子算法性质的启发,我们为编码在高斯玻色采样器中的图同构问题制定了一个必要条件,并提出了一个经典算法来测试该条件。我们的经典算法利用量子采样系统中可高效计算的统计特性,来证明一对图不满足我们的必要条件,因此不能同构。我们在Bràdler等人基于采样器的量子算法、经典颜色细化算法以及最先进的拟多项式Babai算法的背景下分析了我们的算法。

英文摘要

The Noisy Intermediate-Scale Quantum (NISQ) era of technology in which we currently find ourselves is defined by non-universality, susceptibility to errors and noise, and a search for useful applications. While demonstrations of practical quantum advantage remain elusive in this era, it provides space to develop and analyze the advantages and limitations of systems and their ability to solve problems. In this work, we critically assess a proposed quantum algorithm for the graph isomorphism problem, implemented on a photonic quantum device. Inspired by the nature of this quantum algorithm, we formulate a necessary condition for the isomorphism of graphs encoded in Gaussian boson samplers and a classical algorithm to test for it. Our classical algorithm makes use of efficiently computable statistical properties of a quantum sampling system to show a pair of graphs fail to meet our necessary condition and thus cannot be isomorphic. We analyze our algorithm in the context of the inspiring, sampler-based quantum algorithm of Bràdler et. al., the classical color refinement algorithm, and the state-of-the-art quasi-polynomial Babai algorithm.

2512.22914 2026-06-03 eess.SY cs.SY

Distributed Fusion Estimation with Protecting Exogenous Inputs

具有外部输入保护的分布式融合估计

Liping Guo, Jimin Wang, Yanlong Zhao, Ji-Feng Zhang

AI总结 针对分布式融合估计中外部输入隐私泄露问题,提出噪声注入策略,通过松弛非凸优化实现(ε,δ)-差分隐私,并基于协方差交集开发分布式融合估计算法,引入反馈机制提升精度。

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AI中文摘要

在分布式融合估计的背景下,直接将局部估计传输到融合中心可能导致外部输入的隐私泄露。因此,在实现分布式融合估计的同时保护外部输入免受完全窃听至关重要。为了解决这个问题,提出了一种噪声注入策略,通过向传输到融合中心的局部估计中注入相互独立的噪声。为了确定注入噪声的协方差矩阵,构建了一个约束最小化问题,在确保(ε,δ)-差分隐私的同时最小化局部估计的均方误差之和。由于最小化问题的非凸性,提出了一种松弛方法,该方法在不牺牲差分隐私水平的情况下有效解决了最小化问题。然后,基于协方差交集方法开发了一种差分隐私分布式融合估计算法。进一步,通过引入反馈机制,在相同的(ε,δ)-差分隐私前提下提高了融合估计精度。最后,通过一个示例说明了所提算法的有效性,以及差分隐私水平与融合估计精度之间的权衡。

英文摘要

In the context of distributed fusion estimation, directly transmitting local estimates to the fusion center may cause a privacy leakage concerning exogenous inputs. Thus, it is crucial to protect exogenous inputs against full eavesdropping while achieving distributed fusion estimation. To address this issue, a noise injection strategy is provided by injecting mutually independent noises into the local estimates transmitted to the fusion center. To determine the covariance matrices of the injected noises, a constrained minimization problem is constructed by minimizing the sum of mean square errors of the local estimates while ensuring (ε, δ)-differential privacy. Suffering from the non-convexity of the minimization problem, an approach of relaxation is proposed, which efficiently solves the minimization problem without sacrificing differential privacy level. Then, a differentially private distributed fusion estimation algorithm based on the covariance intersection approach is developed. Further, by introducing a feedback mechanism, the fusion estimation accuracy is enhanced on the premise of the same (ε, δ)-differential privacy. Finally, an illustrative example is provided to demonstrate the effectiveness of the proposed algorithms, and the trade-off between differential privacy level and fusion estimation accuracy.

2512.22703 2026-06-03 cond-mat.mes-hall

Minimal d-Band Model for the Optical Susceptibility of Non-Centrosymmetric Monolayer Transition Metal Dichalcogenides

非中心对称单层过渡金属二硫族化物光学响应的最小d带模型

Angiolo Huamán

AI总结 利用Bloch带中主要d轨道成分,通过仅包含三个能带的最小模型,精确计算了非中心对称单层过渡金属二硫族化物的线性和二次光学响应,并复现了第一性原理计算结果。

Comments nine pages, four figures

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AI中文摘要

二维材料的光学响应通常使用平面波基组和完整Bloch波函数从头计算,而未分离最重要的轨道贡献。在缺乏反演对称性的单层过渡金属二硫族化物家族中,我们利用半导体能隙附近Bloch带主要包含d轨道成分的特点,将线性和二次光学响应的计算简化为仅包含三个能带的最小模型。由于Bloch波函数决定了对外场的微观响应,这种简单方法能够很好地复现第一性原理计算在能隙以上约2 eV范围内的结果。这可能是以数值廉价的方式仅用少数能带包含多体效应的起点。

英文摘要

The optical response of two-dimensional materials has been customarily calculated {\it ab initio} using plane waves basis and the full Bloch wavefunction, without separating the most important orbital contributions. In the family of monolayer transition metal dichalcogenides lacking inversion symmetry, we take advantage of the mostly $d-$orbital content of the Bloch bands around the semiconductor gap to reduce the calculation of their linear and quadratic optical susceptibilities to a very minimal model that includes only three energy bands. As the Bloch wavefunction determines the microscopic response to external fields, this simple approach reproduces well first principles calculations up to roughly 2 eV above the band gap. This could be the starting point for the inclusion of many-body effects with only a few energy bands in a numerically inexpensive way.

2512.21962 2026-06-03 quant-ph

Linear Program Witness for Network Nonlocality in Arbitrary Networks

任意网络中网络非局域性的线性规划见证

Salome Hayes-Shuptar, Daniel Bhatti, Ana Belen Sainz, David Elkouss

AI总结 针对网络非局域性认证的非凸问题,提出一种由五类线性约束构建的线性规划见证方法,并在环网络族中验证其有效性。

Comments 14 pages, 5 figures

Journal ref IEEE Journal on Selected Areas in Communications 44, 4585 - 4598 (2026)

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AI中文摘要

网络非局域性将贝尔非局域性扩展到具有多个独立源和参与者的场景。在量子信息处理任务中认证它需要合适的见证。然而,与局域关联相反,网络局域关联的集合是非凸的。这种非凸性使得认证网络非局域性成为一项高度非平凡的任务。现有方法涉及利用网络特定属性,或基于膨胀的方法,其约束随局域变量数量组合增长。在这项工作中,我们引入了一种由五类线性约束构建的网络非局域性线性规划见证。这些类别与网络无关,尽管约束的具体形式必须针对特定网络结构进行定制。我们使用该过程为环网络族构建网络非局域性见证,并仅依赖观测概率和可调实验参数,为一个具体实例认证网络非局域性。我们的工作推进了跨不同量子网络架构认证网络非局域性的高效见证的搜索。

英文摘要

Network nonlocality extends Bell nonlocality to settings with multiple independent sources and parties. Certifying it in quantum information processing tasks requires suitable witnesses. However, in contrast to local correlations, the set of network-local correlations is non-convex. This non-convexity makes certifying network nonlocality a highly non-trivial task. Existing approaches involve leveraging network-specific properties, or inflation-based methods whose constraints grow combinatorially in the number of local variables. In this work, we introduce a linear programming witness for network nonlocality built from five classes of linear constraints. These classes are network-agnostic, although the explicit forms of the constraints must be tailored to a specific network's structure. We use the procedure to construct network nonlocality witnesses for a family of ring networks and certify network nonlocality for a concrete example, relying only on observed probabilities and a tunable experimental parameter. Our work advances the search for efficient witnesses to certify network nonlocality across diverse quantum network architectures.

2512.21612 2026-06-03 cond-mat.mes-hall

Fractional High-Chern Insulator in Twisted Rhombohedral Graphene

扭曲菱方石墨烯中的分数量子反常霍尔绝缘体

Zexu Li, Wenxuan Wang, Fajie Wang, Zaizhe Zhang, Qiu Yang, Kenji Watanabe, Takashi Taniguchi, X. C. Xie, Jie Wang, Kaihui Liu, Zhida Song, Xiaobo Lu

AI总结 本文在伯纳尔双层石墨烯与菱方四层石墨烯构成的莫尔超晶格中,发现了C=1至C=7的量子反常霍尔绝缘体,并在v=2/3处观察到C=7/3的分数阶反常霍尔绝缘体,超越了传统Jain序列和高陈数理论。

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AI中文摘要

分数阶陈绝缘体的实现为在无磁场条件下探索分数电荷激发和任意子统计开辟了可能性。一个核心问题是基于晶格的系统能否产生与传统分数量子霍尔系统截然不同的全新状态。在这项工作中,我们研究了一种由伯纳尔双层石墨烯和菱方四层石墨烯组成的新型莫尔平带系统。我们在v=1和v=3附近发现了前所未有的丰富量子反常霍尔绝缘体,其陈数从C=1到C=7。值得注意的是,我们在v=2/3附近观察到一个奇异的分数阶陈绝缘体,其陈数为C=7/3,这超出了所有已知的由Jain序列或当前高陈数理论描述的分数阶陈绝缘体。我们的工作扩展了对超越朗道能级基础的分数电荷激发的理解,并为探索任意子提供了一个新的莫尔平台。

英文摘要

The realization of fractional Chern insulators opens up the possibility of exploring fractionally charged excitations and anyonic statistics in the absence of a magnetic field. A central question is whether lattice-based systems can give rise to radically new states, distinct from those observed in traditional fractional quantum Hall systems. In this work, we investigate a new type of moiré flat band system composed of Bernal bilayer graphene and rhombohedral tetralayer graphene. We discover an unprecedented richness of quantum anomalous Hall insulators with Chern numbers from C = 1 to C = 7 at v = 1 and around v = 3. Remarkably, we observe an exotic fractional Chern insulator with C = 7/3 around v = 2/3 which is beyond all known fractional Chern insulators described by either the Jain sequence or current high Chern theory. Our work expands the understanding of fractionally charged excitations beyond the Landau level basis and offers a new moire platform for exploring anyons.

2512.20727 2026-06-03 cond-mat.dis-nn cond-mat.mtrl-sci

Statistical mechanics for organic mixed conductors: phase transitions in a lattice gas

有机混合导体的统计力学:晶格气体中的相变

Lukas M. Bongartz

AI总结 采用统计力学方法,将有机混合导体描述为晶格气体,在巨正则系综中分析其一级相变,捕捉低密度和高密度载流子相的形成,并解释器件操作中的历史依赖性。

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AI中文摘要

有机混合导体(OMCs)是一类在生物电子学、物理计算和热电学中具有应用前景的材料。OMCs 具有跨越多个长度和时间尺度的动力学特性,涉及电子、离子和质量传输之间的复杂耦合。这些特性使其与传统半导体显著不同,并阻碍了用传统半导体理论进行描述。在这项工作中,我们使用统计力学方法研究 OMCs 的载流子调制。我们从热力学角度讨论 OMCs,并与已建立的半导体材料进行对比,突出其集体载流子动力学的关键差异。这促使我们将 OMCs 描述为晶格气体,并在巨正则系综中进行分析。该模型表现出类似于经典气-液转变的一级相变,由温度和化学势控制。因此,它捕捉了不同的低密度和高密度载流子相的形成,与最近报道的实验观察一致。它还说明了相边界附近的亚稳态如何导致器件操作中的历史依赖性特征,这是 OMC 晶体管中同样被广泛报道的效应。这项工作旨在简单地将 OMCs 通过统计力学的视角进行研究,提供比传统半导体模型更自然的描述,这些传统模型是为性质根本不同的材料开发的。

英文摘要

Organic mixed conductors (OMCs) represent a promising class of materials for applications in bioelectronics, physical computing, and thermoelectrics. Rather unparalleled, OMCs feature dynamics spanning multiple length and time scales, involving an intricate coupling between electronic, ionic, and mass transport. These characteristics set them notably apart from traditional semiconductors and hinder the description by conventional semiconductor theory. In this work, we approach the charge carrier modulation of OMCs using statistical mechanics. We discuss OMCs from a thermodynamic perspective and contrast them with established semiconductor materials, highlighting key differences in their collective charge carrier dynamics. This motivates our description of OMCs as a lattice gas, which we analyze within the grand canonical ensemble. The model exhibits a first-order phase transition analogous to a classical vapor$\unicode{x2013}$liquid transition, governed by temperature and chemical potential. In doing so, it captures the formation of distinct low- and high-density carrier phases, consistent with recently reported experimental observations. It also illustrates how metastability near the phase boundary can give rise to history-dependent characteristics in device operation, a similarly well-reported effect in OMC transistors. This work is intended as a simple motivation for studying OMCs through the lens of statistical mechanics, offering a more natural description than traditional semiconductor models developed for materials of fundamentally distinct character.

2512.20108 2026-06-03 cs.IT eess.SP math.IT

Generative Spectrum Cartography: Unified Reconstruction and Active Sensing via Diffusion Models

生成式频谱地图:基于扩散模型的统一重建与主动感知

Yuntong Gu, Xiangming meng, Zhiyuan Lin, Sheng Wu, Linling Kuang

AI总结 提出基于扩散模型的后验推断框架GSC,统一解决稀疏、噪声、低比特量化测量下的频谱地图重建与主动感知问题,实现无梯度后验采样与不确定性驱动的测量点选择。

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AI中文摘要

高保真频谱地图对于频谱监测和无线态势感知至关重要,尤其是在基于卫星的广域感知场景中,测量数据稀疏、有噪声且通常为低比特量化。在这种设置下,出现两个耦合的挑战:从严重不完整的测量中准确重建,以及在有限感知预算下高效分配额外的感知资源。现有方法通常分别处理这些问题,并且对于重建,它们通常依赖于在稀疏和量化测量下表达力不足的先验。本文提出生成式频谱地图(GSC),一种基于扩散的后验推断框架,用于具有不确定性感知主动感知的频谱地图。具体地,频谱图恢复被建模为在学习的扩散模型先验下的贝叶斯逆问题,并针对线性和量化测量模型推导出闭式后验均值更新。通过将这些更新嵌入反向扩散过程,GSC实现了无梯度且测量一致的后验采样,无需依赖计算成本高的似然梯度引导。所得后验样本进一步用于估计空间不确定性,并指导主动感知中额外测量位置的多样性感知选择。在模拟电磁地图和高保真模拟卫星监测场景上的实验表明,在稀疏、噪声和低比特量化测量下,GSC相比代表性基线方法实现了更高的PSNR、更低的LPIPS和更高效的感知。

英文摘要

High-fidelity spectrum cartography is important for spectrum monitoring and wireless situational awareness, especially in satellite-based wide-area sensing scenarios where measurements are sparse, noisy, and often low-bit quantized. In such settings, two coupled challenges arise: accurate reconstruction from severely incomplete measurements and efficient allocation of additional sensing resources under a limited sensing budget. Existing methods usually address these problems separately, and, for reconstruction, they often rely on priors that are insufficiently expressive under sparse and quantized measurements. This paper proposes Generative Spectrum Cartography (GSC), a diffusion-based posterior inference framework for spectrum cartography with uncertainty-aware active sensing. Specifically, spectrum map recovery is formulated as a Bayesian inverse problem under a learned diffusion model prior, and closed-form posterior mean updates are derived for both linear and quantized measurement models. By embedding these updates into the reverse diffusion process, GSC enables gradient-free and measurement-consistent posterior sampling without relying on computationally costly likelihood-gradient guidance. The resulting posterior samples are further used to estimate spatial uncertainty and to guide diversity-aware selection of additional measurement locations for active sensing. Experiments on simulated electromagnetic maps and a high-fidelity simulated satellite monitoring scenario show that GSC achieves higher PSNR, lower LPIPS, and more efficient sensing than representative baseline methods under sparse, noisy, and low-bit quantized measurements.

2506.01152 2026-06-03 astro-ph.GA astro-ph.CO

New insights on low-mass dark matter subhalo tidal tracks via numerical simulations

通过数值模拟对低质量暗物质子晕潮汐轨迹的新见解

Alejandra Aguirre-Santaella, Miguel A. Sánchez-Conde, Go Ogiya

AI总结 通过高精度数值模拟研究低质量暗物质子晕在潮汐剥离下的结构参数演化,发现子晕浓度持续上升且速度浓度在近日点比远日点高约两个数量级,揭示了潮汐效应在重塑子晕中的主导作用。

Comments 17 pages, 19 figures, 4 tables. Matches MNRAS published version

Journal ref Mon Not R Astron Soc (2025)

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AI中文摘要

许多研究断言,没有重子对应物且具有内尖点的暗物质(DM)子晕无论受到多大的潮汐力总能存活。在这项工作中,我们进行了一系列专门设计的数值模拟,以分析低质量DM子晕因潮汐剥离导致的$V_\mathrm{max}$、$r_\mathrm{max}$和浓度的演化。我们采用了之前工作arXiv:2207.08652中引入的改进版DASH代码来研究子晕的存活。我们追踪了一个单个DM子晕绕银河系(MW)大小晕的潮汐演化,该晕用重子盘和核球建模,复制了MW的实际质量分布。我们考虑了MW自身随时间演化的引力势的影响。我们以前所未有的精度模拟子晕,改变了它们的初始浓度、轨道参数和内斜率(考虑了NFW和即时尖点)。与之前的文献不同,我们不仅研究了子晕在轨道远心点的结构参数演化(潮汐轨迹),还研究了在近心点的演化,发现前者既有相似之处也有差异——在即时尖点的情况下尤为明显。总体而言,$r_\mathrm{max}$比$V_\mathrm{max}$收缩得更多,导致子晕浓度随时间持续上升。目前的速度浓度比初始下落时高出约两个数量级,近心点潮汐轨迹的速度浓度相对远心点更大。这些发现凸显了潮汐效应在重塑低质量DM子晕中的主导作用,为未来通过模拟和观测进行研究提供了宝贵的见解,例如正确解释卫星星系种群数据、通过引力透镜或恒星流分析寻找子晕,以及间接DM搜索。

英文摘要

Many studies assert that dark matter (DM) subhaloes without a baryonic counterpart and with an inner cusp always survive no matter the strength of the tidal force they undergo. In this work, we perform a suite of numerical simulations specifically designed to analyse the evolution of $V_\mathrm{max}$, $r_\mathrm{max}$ and concentration of low-mass DM subhaloes due to tidal stripping. We employ the improved version of the DASH code, introduced in our previous work arXiv:2207.08652 to investigate subhalo survival. We follow the tidal evolution of a single DM subhalo orbiting a Milky Way (MW)-size halo modeled with a baryonic disc and a bulge replicating the actual mass distribution of the MW. We consider the effect of the time-evolving gravitational potential of the MW itself. We simulate subhaloes with unprecedented accuracy, varying their initial concentration, orbital parameters, and inner slope (both NFW and prompt cusps are considered). Unlike the previous literature, we examine the evolution of subhalo structural parameters -- tidal tracks -- not only at orbit apocentres but also at pericentres, finding in the former case both similarities and differences -- particularly pronounced in the case of prompt cusps. Overall, $r_\mathrm{max}$ shrinks more than $V_\mathrm{max}$, leading to a continuous rise of subhalo concentration with time. The velocity concentration at present is found to be around two orders of magnitude higher than the one at infall, being comparatively larger for pericentre tidal tracks versus apocentres. These findings highlight the dominant role of tidal effects in reshaping low-mass DM subhaloes, providing valuable insights for future research via simulations and observations, such as correctly interpreting data from galaxy satellite populations, subhalo searches with gravitational lensing or stellar stream analyses, and indirect DM searches.

2504.19907 2026-06-03 math.AG math.AC

A short note on Du Bois singularities

关于Du Bois奇点的一个简短注记

Pat Lank

AI总结 研究Du Bois奇点在基变换和纤维积下的行为,证明了在特征零的可嵌入簇中Du Bois奇点从任何域扩张下降,以及具有有理奇点的簇与具有Du Bois奇点的簇的乘积仍具有Du Bois奇点。

Comments It came to my attention that most of this is subsumed by arXiv:0705.4481

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AI中文摘要

我们研究了Du~Bois奇点在基变换和纤维积下的行为。对于特征零的可嵌入簇,我们证明了Du~Bois奇点从任何域扩张下降。我们还证明了具有有理奇点的簇与具有Du~Bois奇点的簇的乘积仍具有Du~Bois奇点,并讨论了曲线乘积的情况。

英文摘要

We study the behavior of Du~Bois singularities under base change and fiber products. For embeddable varieties in characteristic zero, we show that Du~Bois singularities descend from any field extension. We also prove that the product of a variety with rational singularities and a variety with Du~Bois singularities again has Du~Bois singularities, and we discuss the case of products of curves.

2512.14508 2026-06-03 cond-mat.mes-hall cond-mat.mtrl-sci physics.comp-ph

Electrically tunable spin qubits in strain-engineered graphene p-n junctions

应变工程石墨烯p-n结中的电可调自旋量子比特

Myung-Chul Jung, Nojoon Myoung

AI总结 本文通过Rashba自旋轨道耦合和塞曼场,在应变诱导的石墨烯p-n结中实现自旋量子比特操作,并利用紧束缚量子输运模拟和四带模型揭示了自旋守恒和自旋翻转的避让交叉现象。

Comments 37 pages, 12 figures

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AI中文摘要

应变工程能够在原始石墨烯中实现量子限制,同时不降低其本征迁移率和自旋相干性。在这里,我们通过Rashba自旋轨道耦合(RSOC)和塞曼场引入自旋自由度,扩展了先前提出的应变诱导电荷量子比特架构,实现了单层石墨烯(SLG)中的自旋量子比特操作。在石墨烯p-n结中,应变诱导的纳米气泡产生赝磁场,形成具有栅极可调能级杂化的双量子点。紧束缚量子输运模拟和四带模型揭示了两种不同的避让交叉:零失谐时的自旋守恒能隙和有限失谐时的自旋翻转能隙,后者随SOC强度增加而增大,而前者减小。时域模拟证实了与这两种操作区域对应的依赖于失谐的拉比振荡。这些结果表明,应变诱导的限制结合可调SOC为原始石墨烯中的相干自旋操纵提供了一种可行的机制,使应变SLG成为可扩展自旋基量子技术的有前景平台。

英文摘要

Strain engineering enables quantum confinement in pristine graphene without degrading its intrinsic mobility and spin coherence. Here, we extend previously proposed strain-induced charge-qubit architectures by incorporating spin degrees of freedom through Rashba spin-orbit coupling (RSOC) and Zeeman fields, enabling spin-qubit operation in single-layer graphene (SLG). In a graphene p-n junction, a strain-induced nanobubble generates a pseudo-magnetic field that forms double quantum dots with gate-tunable level hybridization. Tight-binding quantum transport simulations and a four-band model reveal two distinct avoided crossings: spin-conserving gaps at zero detuning and spin-flip gaps at finite detuning, the latter increasing with SOC strength while the former decreases. Time-domain simulations confirm detuning-dependent Rabi oscillations corresponding to these two operational regimes. These results demonstrate that strain-induced confinement combined with tunable SOC provides a viable mechanism for coherent spin manipulation in pristine graphene, positioning strained SLG as a promising platform for scalable spin-based quantum technologies.

2512.14209 2026-06-03 gr-qc cond-mat.quant-gas quant-ph

Analogue gravity with Bose-Einstein condensates

玻色-爱因斯坦凝聚体中的类比引力

Adrià Delhom, Luca Giacomelli

AI总结 本文以玻色-爱因斯坦凝聚体为平台,通过理论描述和数值方法,系统介绍了类比黑洞、超辐射和霍金辐射等类比引力现象。

Comments Lecture notes based on the course given by Luca Giacomelli at "Analogue Gravity in 2023, Benasque". 71 pages, 13 figures, 10 solved problems (with 3 attached Julia notebooks)

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AI中文摘要

类比引力探索凝聚态系统中的集体激发如何再现弯曲时空中的场行为。一个重要的例子是运动流体中可能出现的声学黑洞。在这些讲义中,我们聚焦于原子玻色-爱因斯坦凝聚体(BECs),这些量子流体因其精确的理论描述、显著的实验控制以及允许声音量子性质显现的超低温度,为类比引力研究提供了有趣的平台。我们给出类比黑洞和BECs及其基本激发的理论描述的教学性介绍,这些激发表现为弯曲时空中的量子场。然后,我们应用这些工具来概述当前对黑洞超辐射和类比霍金辐射的理解,包括显式例子和数值方法。

英文摘要

Analogue gravity explores how collective excitations in condensed matter systems can reproduce the behavior of fields in curved spacetimes. An important example is the acoustic black holes that can occur for sound in a moving fluid. In these lecture notes, we focus on atomic Bose-Einstein condensates (BECs), quantum fluids that provide an interesting platform for analogue gravity studies thanks to their accurate theoretical description, remarkable experimental control, and ultralow temperatures that allow the quantum nature of sound to emerge. We give a pedagogical introduction to analogue black holes and the theoretical description of BECs and their elementary excitations, which behave as quantum fields in curved spacetimes. We then apply these tools to survey the current understanding of black-hole superradiance and analogue Hawking radiation, including explicit examples and numerical methods.

2506.17524 2026-06-03 math.NA cs.NA math.DS

Coordinate-wise splitting algorithms for ODE simulation via Koopman-Lie product formulas

基于Koopman-Lie乘积公式的ODE模拟坐标分裂算法

Arun Banjara, Ibrahem AlJabea, Theodore Papamarkou, Frank Neubrander

AI总结 提出一种结合经典Koopman-Lie乘积公式与坐标冻结子流的常微分方程数值模拟框架,通过坐标分解将向量场转化为一维子问题求解,并在Lotka-Volterra、Van der Pol和Lorenz系统上验证了算法性能。

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AI中文摘要

我们提出了一种计算框架,通过将经典Koopman-Lie乘积公式与坐标冻结子流相结合,模拟有限维常微分方程。该设置是模型已知的,因为假设向量场可用,且不尝试数据驱动的Koopman算子逼近。在标准假设下,与流相关的Koopman-Lie生成元允许坐标分解为部分生成元。这种分解导致基本更新,其中除一个状态变量外所有变量都被冻结,所得冻结标量子问题通过闭式解或一维求解进行评估。然后,Lie-Trotter、Strang和高阶指数组合被转化为二维和三维系统的状态更新算法,半群和乘积公式理论作为构造的背景依据。我们还记录了实现中使用的递归构造产生的指数项计数。这些计数作为实现成本呈现。在Lotka-Volterra、Van der Pol和Lorenz系统上的数值实验将坐标分裂算法与高精度RK45参考解进行比较,使用均方根误差和工作精度曲线。结果说明了分裂阶数、时间步数、指数因子数量和运行时间之间的实际权衡。

英文摘要

We present a computational framework for simulating finite-dimensional ordinary differential equations by combining classical Koopman-Lie product formulas with coordinate-wise frozen subflows. The setting is model-known, since the vector field is assumed to be available, and no data-driven approximation of the Koopman operator is attempted. Under standard assumptions, the Koopman-Lie generator associated with the flow admits a coordinate decomposition into partial generators. This decomposition leads to elementary updates in which all but one state variable are frozen, and the resulting frozen scalar subproblems are evaluated either in closed form or by one-dimensional solves. Lie-Trotter, Strang, and higher-order exponential compositions are then converted into state-update algorithms for two- and three-dimensional systems, with the semigroup and product-formula theory used as background justification for the constructions. We also record the exponential-term counts produced by the recursive constructions used in the implementation. These counts are presented as implementation costs. Numerical experiments on the Lotka-Volterra, Van der Pol, and Lorenz systems compare the coordinate-wise splitting algorithms with high-accuracy RK45 reference solutions using root-mean-square errors and work-precision curves. The results illustrate the practical trade-off between splitting order, number of time steps, number of exponential factors, and runtime.

2512.12312 2026-06-03 physics.ed-ph physics.app-ph physics.class-ph

Exploring Fourier methods with beer bottles

用啤酒瓶探索傅里叶方法

David Kordahl, Emma Foster

AI总结 本文通过啤酒瓶的声学共振实验,展示了如何将啤酒瓶建模为一维受驱阻尼振荡器,并利用傅里叶方法快速采集数据拟合模型参数,适用于本科实验教学。

Comments 7 pages, 6 figures, Forthcoming from American Journal of Physics

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AI中文摘要

任何曾对着啤酒瓶口吹气的人都知道,啤酒瓶具有明确的基频。本文展示了如何将啤酒瓶的声学共振建模为一维受驱阻尼振荡器,并提供了足够的细节以便在本科实验中使用。虽然可以通过顺序纯音测量提取瓶子的频域格林函数,但使用傅里叶方法时,只需几秒钟即可收集足够的数据来拟合模型参数。

英文摘要

As anyone who has blown across the mouth of a beer bottle knows, beer bottles have a well-defined fundamental frequency. This paper shows how a beer bottle's acoustical resonance can be modeled as a one-dimensional driven-damped oscillator and includes enough detail to be useful in undergraduate laboratory experiments. While the frequency-domain Green's function of the bottle can be extracted through sequential pure-tone measurements, sufficient data to fit the model's parameters can be collected in just a few seconds when Fourier methods are used.

2408.04210 2026-06-03 eess.SP

Least-Squares Adaptive Filter-Based Cohen's Class Time-Frequency Distribution for Signal Denoising

基于最小二乘自适应滤波的Cohen类时频分布用于信号去噪

Manjun Cui, Zhichao Zhang, Yangfan He

AI总结 提出一种在Wigner-Ville分布域中集成Wiener滤波原理和时频滤波机制的最小二乘自适应滤波方法,设计出核函数可自动调整以实现最小均方误差去噪的Cohen类时频分布,在典型雷达信号和心电数据上优于现有方法。

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AI中文摘要

受自适应核Cohen类时频分布(CCTFD)用于交叉项抑制的启发,本文旨在探索用于去噪的新型自适应核函数,特别关注实际应用中的非平稳信号处理。我们将Wiener滤波原理与CCTFD的时频滤波机制相结合,在Wigner-Ville分布(WVD)域中设计最小二乘自适应滤波方法,从而产生基于最小二乘自适应滤波的CCTFD,其核函数可随输入信号自动调整,以实现WVD域中的最小均方误差去噪。对典型模拟雷达信号和真实心电数据的数值实验全面表明,所提出的自适应CCTFD在噪声抑制方面优于几种最先进的方法。

英文摘要

Inspired by the use of adaptive kernel-based Cohen's class time-frequency distributions (CCTFDs) for cross-term suppression, this paper aims to explore novel adaptive kernel functions for denoising, with a particular focus on non-stationary signal processing in practical applications}. We integrate Wiener filter principle and the time-frequency filtering mechanism of CCTFD to design the least-squares adaptive filter method in the Wigner-Ville distribution (WVD) domain, giving birth to the least-squares adaptive filter-based CCTFD whose kernel function can be adjusted with the input signal automatically to achieve the minimum mean-square error denoising in the WVD domain. {Numerical experiments on typical simulated radar signals and real-world electrocardiogram data comprehensively demonstrate that the proposed adaptive CCTFD outperforms several state-of-the-art methods in noise suppression.

2512.11969 2026-06-03 astro-ph.HE

Detection of Partial Coherence due to Multipath Propagation for FRB 20220413B with CHIME/FRB

利用CHIME/FRB探测FRB 20220413B因多径传播引起的部分相干性

Zarif Kader, Evan Davies-Velie, Matt Dobbs, Afrokk Khan, Calvin Leung, Robert Main, Kiyoshi W. Masui, Kenzie Nimmo, Ue-Li Pen, Mawson Sammons

AI总结 通过分析FRB 20220413B的时滞相关性和频谱特征,发现其观测特征与等离子体透镜模型部分一致,但缺乏相位相干性,表明存在共同散射屏而非相干等离子体透镜。

Comments 20 pages, 12 figures

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AI中文摘要

快速射电暴(FRB)是一种持续时间约毫秒的瞬变现象,传播于河外距离,本质上是一个点源。通过非均匀等离子体分布的无线电波传播可起到透镜作用,产生发射电场的多个像。透镜可产生点源的像,其中像之间的电场相位在射电望远镜观测时保持相干。FRB 20220413B显示出复杂的脉冲结构,具有时间分离的成分,这些成分可能是由于等离子体透镜效应产生的主成分的像副本。我们进行了多项分析以确定FRB 20220413B是否与等离子体透镜FRB的预期一致。我们分析并拟合了爆发的形态到等离子体透镜模型,发现频谱-时间轮廓一致,但观测流量不一致。利用CHIME望远镜的复值通道化电压数据,我们进行了时滞相关性分析,并报告了FRB 20220413B电场中存在的相关特征。我们发现仅在绝对功率中存在多余的相关特征,而在相位中不存在。我们对爆发所有子成分的频谱进行了频率滞后相关性分析,发现所有成分的闪烁带宽一致。我们发现闪烁带宽与银河系散射的预期一致。我们将其解释为所有爆发成分通过位于银河系中的同一闪烁屏传播,这将产生观测到的多余方差特征,即使爆发成分之间缺乏相位相干性。我们发现,虽然爆发形态可以用等离子体透镜建模,但时滞相关性中存在的相干特征与共同散射屏的预期一致,而与相干等离子体透镜不一致。

英文摘要

Fast radio bursts (FRBs) are a $\sim$ millisecond-long transient phenomenon that propagate across extragalactic distances and are effectively a point source. Radio wave propagation through inhomogeneous distributions of plasma can act as a lens, generating multiple images of the emitted electric field. A lens can produce images of a point source where the phase of the electric field between images remains coherent when observed by a radio telescope. FRB 20220413B shows a complicated pulse structure with time separated components that may be image copies of the main components due to plasma lensing. We perform several analyses to determine if FRB 20220413B is consistent with expectations of a plasma lensed FRB. We analyze and fit the morphology of the burst to a plasma lens model and find consistency in the spectro-temporal profile but not the observed flux. Using the complex-valued channelized voltage data from the CHIME telescope, we perform a time-lag correlation analysis and report correlation signatures present in the electric field of FRB 20220413B. We find that there exists an excess correlation signature only in absolute power and not in phase. We perform a frequency-lag correlation analysis on the spectra of all subcomponents of the burst and find a consistent scintillation bandwidth across all components. We find the scintillation bandwidth is consistent with expectations of scattering due to the Milky Way. We interpret this as all burst components propagating through the same scintillation screen located in the Milky Way, which would generate the excess variance signature observed, even in the absence of phase coherence between burst components. We find that while the burst morphology can be modeled by a plasma lens, the coherent signature present in the time-lag correlation is consistent with the expectations of a common scattering screen, but not coherent plasma lensing.

2312.08106 2026-06-03 math.FA math.MG

A remark on characterizing inner product spaces via strong three-point homogeneity

关于通过强三点齐次性刻画内积空间的一个注记

Sujit Sakharam Damase, Apoorva Khare

AI总结 本文证明赋范线性空间等距同构于内积空间当且仅当它对任意(或每个)n≥3是强n点齐次度量空间,而n=2的情形对应Banach-Mazur问题。

Comments Significantly expanded, including adding details in the proof of Theorem 4; the statement of Theorem 10; and all of Section 3. Final version, 9 pages, to appear in the Canadian Mathematical Bulletin

Journal ref Can. Math. Bull. 69 (2026) 677-687

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AI中文摘要

我们证明,一个赋范线性空间等距同构于内积空间当且仅当它对任意(或每个)$n \geqslant 3$是强$n$点齐次度量空间。$n=2$的情形对应Banach-Mazur问题。

英文摘要

We show that a normed linear space is isometrically isomorphic to an inner product space if and only if it is a strongly $n$-point homogeneous metric space for any (or every) $n \geqslant 3$. The counterpart for $n=2$ is the Banach-Mazur problem.

2512.11775 2026-06-03 cs.DC cs.CR cs.NI

Hypergraph based Multi-Party Payment Channel

基于超图的多方支付通道

Ayush Nainwal, Atharva Kamble, Nitin Awathare

AI总结 提出基于超图的COALESCE协议,通过集体资助的超边实现无领导者、高并发支付,消除路由依赖和流动性碎片化,在150节点测试中达到约94%的成功率。

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AI中文摘要

公有链本质上提供低吞吐量和高延迟,这促使了诸如支付通道网络(PCN)等链下可扩展性解决方案。然而,现有的PCN存在流动性碎片化(锁定在一个通道中的资金无法在其他地方重用)和通道耗尽问题,这两者都限制了路由效率并降低了交易成功率。多方通道(MPC)结构缓解了这些问题,但它们通常依赖于领导者或协调者,造成单点故障,并且为通道间支付提供的灵活性有限。 我们引入了基于超图的多方支付通道(COALESCE),这是一种新的链下结构,用集体资助的超边替代了双边通道。这些超边通过可验证的、提议者排序的DAG更新,实现了完全并发、无领导者的超内和超间支付,比之前的设计提供了显著更大的灵活性和并发性。因此,我们的设计消除了路由依赖,避免了方向性流动性锁定,并且不需要诸如监视塔之类的中央监控服务。 我们在150节点超内实现中,在高负载(较大支付金额)下实现了约94%的交易成功率,而在15000节点网络上进行的完整超边评估中,成功率维持在85%到95%之间,没有HTLC过期或路由失败,突显了COALESCE的鲁棒性。

英文摘要

Public blockchains inherently offer low throughput and high latency, motivating off-chain scalability solutions such as Payment Channel Networks (PCNs). However, existing PCNs suffer from liquidity fragmentation-funds locked in one channel cannot be reused elsewhere-and channel depletion, both of which limit routing efficiency and reduce transaction success rates. Multi-party channel (MPC) constructions mitigate these issues, but they typically rely on leaders or coordinators, creating single points of failure and providing only limited flexibility for inter-channel payments. We introduce Hypergraph-based Multi-Party Payment Channels (COALESCE), a new off-chain construction that replaces bilateral channels with collectively funded hyperedges. These hyperedges enable fully concurrent, leaderless intra- and inter-hyperedge payments through verifiable, proposer-ordered DAG updates, offering significantly greater flexibility and concurrency than prior designs. Hence our, design eliminates routing dependencies, avoids directional liquidity lock-up, and does not require central monitoring services such as watchtowers. Our implementation on a 150-node intra-hyperedge achieves a transaction success rate of approximately 94% under heavy load (larger payment sizes), while full hyperedge evaluation over a 15,000-node network sustains success rates in the range of 85% to 95%, without HTLC expiry or routing failures, highlighting the robustness of COALESCE.

2512.11190 2026-06-03 cond-mat.str-el

Multiloop functional renormalization group from single bosons

单玻色子多圈泛函重整化群

Kilian Fraboulet, Aiman Al-Eryani, Sarah Heinzelmann, Anna Kauch, Sabine Andergassen

AI总结 本文提出多圈单玻色子交换泛函重整化群方法,应用于弱耦合二维Hubbard模型,通过忽略多玻色子交换贡献的流,在圈收敛时精确重现parquet近似结果。

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AI中文摘要

泛函重整化群(fRG)是处理关联电子系统(特别是描述竞争不稳定性)的成熟工具。近年来,方法学进展导致了fRG的多圈扩展,该系统性地包含了超越传统单圈截断的圈修正,并提供了二维晶格系统的定量准确描述。同时,双粒子顶点的单玻色子交换(SBE)分解已被证明在计算和解释方面都具有优势,为更经济的近似方案铺平了道路。我们在此将其组合称为多圈SBE fRG,应用于弱耦合二维Hubbard模型。在详细阐述了物理通道中的底层形式后,我们分析了频率和动量依赖的顶点函数的结果。我们发现,SBE近似(即忽略多玻色子交换贡献的流)在圈收敛时精确重现了parquet近似。所提出的算法改进为处理更具挑战性的参数区域和更现实的模型开辟了道路。

英文摘要

The functional renormalization group (fRG) is an established tool in the treatment of correlated electron systems, notably for the description of competing instabilities. In recent years, methodological advancements led to the multiloop extension of the fRG, which systematically includes loop corrections beyond the conventional one-loop truncation and yields a quantitatively accurate description of two-dimensional lattice systems. At the same time, the single-boson exchange (SBE) decomposition of the two-particle vertex has been shown to offer both computational and interpretative advantages paving the way to more affordable approximation schemes. We here apply their combination coined as multiloop SBE fRG to the two-dimensional Hubbard model at weak coupling. After providing a detailed account of the underlying formalism in physical channels, we analyze the results for the frequency- and momentum-dependent vertex functions. We find that the SBE approximation, i.e., neglecting the flow of the multi-boson exchange contributions, accurately reproduces the parquet approximation at loop convergence. The presented algorithmic improvement opens the route for the treatment of more challenging parameter regimes and more realistic models.

2406.12561 2026-06-03 math.NT

A positive density of elliptic curves are diophantine stable in certain Galois extensions

椭圆曲线在特定伽罗瓦扩张中具有正密度的丢番图稳定性

Anwesh Ray, Pratiksha Shingavekar

AI总结 本文证明,对于循环p-扩张L/Q(p=3或5),存在正密度的椭圆曲线E(按高度排序)在L中具有丢番图稳定性。

Comments Version 2: 23 pages, accepted for publication in Forum Mathematicum

Journal ref Forum Math. Vol. 38 (2026), no. 5, pp.1453-1468

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AI中文摘要

设 $p \in \{3, 5\}$ 并考虑循环 $p$-扩张 $L/\mathbb{Q}$。我们证明,存在一个有效的正密度的椭圆曲线 $E$(定义在 $\mathbb{Q}$ 上,按高度排序)在 $L$ 中具有丢番图稳定性。

英文摘要

Let $p \in \{3, 5\}$ and consider a cyclic $p$-extension $L/\mathbb{Q}$. We show that there exists an effective positive density of elliptic curves $ E $ defined over $ \mathbb{Q} $, ordered by height, that are diophantine stable in $ L $.

2512.09658 2026-06-03 quant-ph

Entanglement with a mode observable via a tunable interaction with a qubit

通过可调谐与量子比特的相互作用实现与模式可观测量的纠缠

Małgorzata Strzałka, Radim Filip, Katarzyna Roszak

AI总结 研究通过仅测量量子比特来检测“自旋-玻色”纠缠的方案,利用可调谐耦合克服固定相互作用中的对称性限制,并以超导transmon量子比特与微波腔相互作用为例,提出实验可行的哈密顿参数并验证有限温度下信号仍显著。

Comments 8 pages, 3 figures

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AI中文摘要

我们研究了通过仅测量量子比特来检测“自旋-玻色”纠缠的可能性。由于耦合和环境初始状态的内在对称性,这种纠缠无法通过先前提出的涉及固定系统-环境相互作用的方案检测到。我们利用了在某些量子比特实现中可用的量子比特-环境耦合的可调谐性。作为例子,我们研究了与微波腔相互作用的超导transmon量子比特,这是此类系统之一,并且在量子信息处理中至关重要。我们为检测方案的制备和测量阶段提出了合适的哈密顿参数,以实现实验测试,并验证了在有限温度下报告的信号仍然不可忽略地大。

英文摘要

We study the possibility of detection of ``spin-boson'' entanglement by qubit only measurements. Such entanglement is impossible to detect by previously proposed schemes that involve a fixed system-environment interaction, because of inherent symmetries within the coupling and the initial state of the environment. We take advantage of the possibility of tuning of qubit-environment coupling, that is available in some qubit realizations. As an example we study a superconducting transmon qubit interacting with a microwave cavity, which is one of such systems and is, furthermore, essential in the context of quantum information processing. We propose suitable Hamiltonian parameters for the preparation and measurement phases of the detection scheme that allow for an experimental test, and verify that the reported signal is nonnegligibly large still at finite temperatures.

2512.08928 2026-06-03 astro-ph.HE

Resolving the (Debate About) Nozzle Shocks in Tidal Disruption Events

解决潮汐瓦解事件中喷管激波的(争论)

Zachary L. Andalman, Eliot Quataert, Eric R. Coughlin, C. J. Nixon

AI总结 通过结合3D SPH模拟、半解析仿射模型和1D有限体积模拟,研究潮汐瓦解事件中喷管激波对碎片流演化和圆化过程的影响,发现氢重组和分子氢形成使流增宽约5倍,增强喷管耗散,但不足以直接圆化,而是增加二次轨道自交可能性。

Comments 19 pages main body, 23 pages total, 17 figures. Accepted by OJA on June 1st, 2026. Resubmitted for 2nd review on May 8th, 2026. Originally submitted to OJA on Dec 10th, 2025. Comments welcome. The code to generate our EOS tables is available at https://zandalman.com/publications/Andalman+2026a/

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AI中文摘要

当一颗恒星进入超大质量黑洞的洛希极限内时,会被黑洞的潮汐场撕裂,产生潮汐瓦解事件(TDE)。由此产生的耀斑由束缚星体碎片的圆化和吸积驱动,这些碎片最初以细长的碎片流形式在偏心轨道上返回黑洞。返回的流体元素沿倾斜轨道运动,在近心点附近汇聚,导致极端垂直压缩至尺度$10^{-4}~R_\odot$,并形成喷管激波。喷管激波处的耗散可能通过改变碎片流的性质影响圆化过程,但其作用一直是争论的焦点。我们结合三维光滑粒子流体动力学模拟、半解析仿射模型和一维有限体积流体动力学模拟,发展了一个碎片流演化的理想化模型。由于我们的模型计算成本低,可以明确解析喷管激波,使用真实的状态方程,并在多个不同时刻追踪碎片流演化。在峰值回落附近,氢重组和分子氢形成使流增宽约5倍,增强了喷管处的耗散。然而,耗散仍不足以通过面内压力梯度直接圆化碎片。相反,更厚的流显著增加了碎片流在第二次轨道上自交的可能性,尽管存在相对论性节点进动。自交处的流性质对喷管耗散和碎片弹道轨迹汇聚的焦点时间敏感。我们的结果阐明了喷管激波在TDE圆化过程中的作用,为更真实的圆化和辐射模型提供了基础。

英文摘要

When a star passes within the Roche limit of a supermassive black hole (SMBH), it is pulled apart by the BH's tidal field in a tidal disruption event (TDE). The resulting flare is powered by the circularization and accretion of bound stellar debris, which initially returns to the BH on eccentric orbits in a thin debris stream. The returning fluid elements follow inclined orbits that converge near pericenter, resulting in extreme vertical compression to scales $10^{-4}~R_\odot$ and the formation of a nozzle shock. Dissipation at the nozzle shock may affect circularization by altering the properties of the debris stream, but its role is the subject of ongoing debate. We develop an idealized model for the debris stream evolution combining 3D smoothed-particle hydrodynamics simulations, the semi-analytic affine model, and 1D finite-volume hydrodynamic simulations. Because our model is computationally cheap, we can unambiguously resolve the nozzle shock, use a realistic equation of state, and follow the debris stream evolution at many different times. Near peak fallback, Hydrogen recombination and molecular Hydrogen formation broaden the stream by a factor $\sim 5$, enhancing dissipation at the nozzle. However, the dissipation is still insufficient to directly circularize the debris by in-plane pressure gradients. Instead, the thicker stream substantially increases the likelihood that the stream self-intersects on the second orbit, despite relativistic nodal precession. The stream properties at self-intersection are sensitive to dissipation at the nozzle and the timing of focal points where the ballistic trajectories of the debris converge. Our results clarify the nozzle shock's role in circularization in TDEs, providing a foundation for more realistic circularization and emission models.

2512.08913 2026-06-03 physics.chem-ph

Effect of the Gradient of the Spin-Polarization in Density Functional Approximations

密度泛函近似中自旋极化梯度的影响

Rohan Maniar, John P. Perdew

AI总结 通过引入梯度展开中缺失的∇ζ相关项,修正SCAN泛函,在不影响sp体系精度的前提下改善过渡金属原子和分子的描述。

Comments 7 pages, 4 tables, 1 figure

Journal ref Phys. Rev. A 113, 042210 (2026)

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AI中文摘要

非经验密度泛函近似的构建通常以精确约束的满足为指导。一个重要的约束是恢复缓慢变化电子密度的梯度展开。在先前的半局域密度泛函近似构建中,关联梯度展开中的∇ζ依赖项被忽略,其中ζ是相对自旋极化。我们提出一种方案,可以在不显著影响其他约束和规范的情况下,将这些项重新引入已构建的泛函中。我们将此方案应用于强约束与适当规范(SCAN)泛函,构建了∇ζ修正版本的SCAN。结果表明,所得泛函在过渡金属原子和分子上有所改进,同时未显著影响SCAN对sp体系的准确描述。对于铬二聚体Cr₂的结合能曲线,SCAN的欠结合在大键长下得到完全修正,在小键长下有所减小。

英文摘要

The construction of non-empirical density functional approximations is typically guided by the satisfaction of exact constraints. An important constraint is the recovery of the gradient expansion for slowly varying electron densities. In prior constructions of semilocal density functional approximations, the $\nabla ζ$-dependent terms in the gradient expansion of the correlation have been dropped, where $ζ$ is the relative spin polarization. We propose a scheme by which such terms can be reintroduced into already constructed functionals without significantly affecting other constraints and norms. We implement this scheme on the Strongly Constrained and Appropriately Normed (SCAN) functional to construct a $\nabla ζ$-corrected version of SCAN. The resulting functional is shown to provide improvements in transition-metal atoms and molecules without significantly affecting SCAN's accurate description of $sp$-systems. For the binding energy curve of the chromium dimer Cr$_2$, the SCAN underbinding is fully corected at large bond lengths and reduced at short bond lengths.

2512.07066 2026-06-03 astro-ph.HE

Trends in gravitational wave emission in axisymmetric simulations of rotating core-collapse supernovae

旋转核心坍缩超新星轴对称模拟中引力波发射的趋势

Bailey Sykes, Bernhard Müller

AI总结 通过一系列不同初始旋转速率的轴对称磁流体动力学模拟,研究了旋转对核心坍缩超新星引力波信号振幅和频率的影响,发现快速旋转导致高频(高达3 kHz)引力波,且频率和振幅随旋转加快而降低,未观察到共振放大。

Comments 24 pages, 18 figures. Accepted by PRD

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AI中文摘要

强旋转对核心坍缩超新星(CCSNe)反弹后引力波(GW)信号振幅和频率的定量影响尚未完全理解。为了研究频率和振幅的趋势,以及可能的壮观现象如共振放大,我们对一个17 $M_\odot$ 前身星进行了一系列轴对称长时标磁流体动力学CCSN模拟,初始旋转速率从0.29 rad/s到3.48 rad/s精细间隔。我们发现这些旋转模型产生的引力波频率高达3 kHz,高于文献中典型的非旋转模型。高频源于快速旋转的原中子星的小极半径和低纬度角动量梯度的稳定化。引力波频率和振幅随旋转加快而降低。与两个无磁场的补充模拟不同,磁流体动力学模型的特征是在主导的高频发射带之上缺少p模。我们没有发现任何旋转速率下的共振模放大迹象,尽管时空和空间频率分析揭示了原中子星和增益区域之间一些有趣的四极运动耦合。需要发展广义的多维扰动技术来研究快速旋转大质量恒星坍缩中的模结构和模相互作用。

英文摘要

The quantitative impact of strong rotation on the amplitudes and frequencies of the post-bounce gravitational wave (GW) signal from core-collapse supernovae (CCSNe) is still not fully understood. To study trends in frequencies and amplitudes, and possibly spectacular phenomena like resonant amplification, we perform a series of axisymmetric long-duration magnetohydrodynamic CCSN simulations of a 17 $M_\odot$ progenitor using a finely spaced grid in initial rotation rate from 0.29 rad/s to 3.48 rad/s. We find that these rotating models produce GWs at frequencies of up to 3 kHz, higher than in typical non-rotating models in the literature. The high frequencies arise due to small polar radii of rapidly rotating proto-neutron stars and stabilization by angular momentum gradients at lower latitude. GW frequencies and amplitudes tend to decrease with faster rotation. Different from two complementary simulations without magnetic fields, the magnetohydrodynamic models are characterized by an absence of p-modes above the dominant high-frequency emission band. We find no indication of resonant mode amplification for any rotation rate, although a temporo-spatial and space-frequency analysis reveals some interesting couplings of quadrupolar motions across the proto-neutron star and the gain region. Generalized, multi-dimensional perturbative techniques need to be developed to study the mode structure and mode interaction in the collapse of rapidly rotating massive stars.

2301.02631 2026-06-03 gr-qc

Tsallis holographic inflation in $f(R,T)$ gravity: CMB constraints, reheating, and swampland implications

Tsallis全息暴胀在$f(R,T)$引力中的CMB约束、再加热与沼泽地含义

S. Taghavi, T. Golanbari, Kh. Saaidi

AI总结 本研究在$f(R,T)$引力框架下,利用Tsallis全息暗能量密度作为暴胀势,通过CMB数据、沼泽地准则、再加热物理和原初引力波限制,构建了自洽的全息暴胀模型。

Comments 22 pages, 14 figures, 2 tables

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AI中文摘要

理解早期宇宙暴胀如何从修正引力中的广义全息能量密度中产生,推动了本分析。我们在$f(R,T)$引力中发展了一个自洽的暴胀场景,其中Tsallis全息暗能量密度有效充当暴胀势。使用Granda-Oliveros红外截断,我们推导了相应的慢滚关系,并识别了参数空间$(α,β,δ,λ)$中与ACT DR6(P-ACT-LB)约束一致的一个广阔区域。通过利用THDE密度对哈勃率的依赖,我们重建了暴胀势$V(ϕ)$,并表明场偏移$Δϕ$和归一化势梯度$|V'|/(V M_{p})$主要由物质-几何耦合$λ$控制。我们证明$λ\gtrsim \mathcal{O}(10^{2})$将场偏移抑制在普朗克尺度以下,并确保$|V'|/(V M_{p}) \ge 1$,从而同时满足距离猜想和精细化的德西特沼泽地界限。我们还分析了再加热阶段。除了原初核合成要求$T_{ m BBN} \approx 4~\mathrm{MeV}$(这设定了再加热温度的下限),观测界限$ΔN_{ m eff} \le 0.17$从原初引力波施加了额外约束。在刚性再加热阶段($ω_{ m re} > 1/3$),高频PGW谱显著增强,产生一个可能落入即将到来的探测器灵敏度范围内的独特信号。总体而言,这项工作提供了$f(R,T)$引力中全息暴胀的一个观测一致实现,受到CMB数据、沼泽地准则、再加热物理和PGW限制的共同约束。

英文摘要

Understanding how early-universe inflation may emerge from generalized holographic energy densities within modified gravity motivates the present analysis. We develop a self-consistent inflationary scenario in which the Tsallis holographic dark energy (THDE) density effectively acts as the inflaton potential in $f(R,T)$ gravity. Using the Granda-Oliveros infrared cutoff, we derive the corresponding slow-roll relations and identify a broad region of the parameter space $(α,β,δ,λ)$ that remains consistent with ACT DR6 (P-ACT-LB) constraints. By exploiting the dependence of the THDE density on the Hubble rate, we reconstruct the inflaton potential $V(ϕ)$ and show that both the field excursion $Δϕ$ and the normalized potential gradient $|V'|/(V M_{p})$ are predominantly controlled by the matter-geometry coupling $λ$. We demonstrate that $λ\gtrsim \mathcal{O}(10^{2})$ suppresses the field excursion below the Planck scale and ensures $|V'|/(V M_{p}) \ge 1$, thereby satisfying both the distance conjecture and the refined de Sitter swampland bound. We also analyze the reheating stage. In addition to the primordial nucleosynthesis requirement $T_{\rm BBN} \approx 4~\mathrm{MeV}$, which sets a lower limit on the reheating temperature, the observational bound $ΔN_{\rm eff} \le 0.17$ imposes an additional constraint from primordial gravitational waves (PGWs). During stiff reheating phases with $ω_{\rm re} > 1/3$, the high-frequency PGW spectrum is significantly enhanced, producing a distinct signature that may fall within the sensitivity of upcoming detectors. Overall, this work provides an observationally consistent realization of holographic inflation in $f(R,T)$ gravity, jointly constrained by CMB data, swampland criteria, reheating physics, and PGW limits.