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2605.22130 2026-05-22 physics.bio-ph

Conditional Enhancement of Radical Pair Dynamics via Chiral State Preparation

通过手性态制备条件性增强自由基对动力学

Tristen Gwynn, Betony Adams, Francesco Petruccione

AI总结 该研究探讨了在自由基对机制(RPM)哈密顿量参数空间中,手性诱导自旋选择性(CISS)对磁敏感性的影响,发现其增强效应依赖于内部超精细和偶极相互作用轴的相对对齐,且在非共线性相互作用条件下尤为显著。

Comments 17 pages, 19 figures

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AI中文摘要

手性诱导自旋选择性(CISS)已被证明在特定哈密顿量条件下能增强自由基对机制(RPM)模型中的磁敏感性,但这些增强效应在更广泛参数空间中的持续性尚未被测试。我们将CISS效应作为自旋依赖的初始态和重组算符,系统地评估了RPM哈密顿量全面参数扫描下的自由基对自旋动力学。我们通过场反转下的对称和反对称分解来表征取向响应,提供了一种直接的定量CISS诱导对称破缺的特征。我们的分析表明,CISS不作为磁敏感性的通用放大器。所声称的增强效应依赖于内部超精细和偶极相互作用轴的相对对齐,特别是在非共线性内部相互作用条件下。扩展到双核模型证实这些增强效应对核自旋敏感。在单核模型中观察到的CISS诱导效应在引入第二个共线核时被显著抑制,除了在超精细轴旋转扫描中,非共线性张量错位驱动了稳健的反对称响应。这些发现表明,CISS增强磁受体的条件比之前所展示的更为严格,需要高度有序和刚性的分子几何结构来维持该效应。

英文摘要

Chiral-induced spin selectivity (CISS) has been shown to enhance magnetic sensitivity in radical pair mechanism (RPM) models under specific Hamiltonian conditions, yet whether these enhancements persist across a broader parameter space remains untested. We incorporate the CISS effect as a spin-dependent initial state and recombination operator and systematically evaluate the spin dynamics of a model radical pair across a comprehensive parameter sweep of the RPM Hamiltonian. We characterise the orientational response through symmetric and antisymmetric decomposition of the yield distribution under field reversal, providing a direct quantitative signature of CISS-induced symmetry breaking. Our analysis demonstrates that CISS does not function as a generic amplifier of magnetic sensitivity. Claimed enhancements are conditional on the relative alignment of the internal hyperfine and dipolar interaction axes, arising specifically under conditions of non-collinear internal interactions. Extension to a two-nucleus model confirms that these enhancements are sensitive to nuclear spin. CISS-induced effects observed in the single-nucleus model are substantially suppressed when a second collinear nucleus is introduced, with the exception of the hyperfine axis rotation sweep where non-collinear tensor misalignment drives a robust antisymmetric response. These findings indicate that the conditions for CISS-enhanced magnetoreception are more stringent than previously demonstrated, requiring highly ordered and rigid molecular geometries to sustain the effect.

2605.22129 2026-05-22 math.GT

On Isotopies and hyperbolicity of weaves

关于织物的同胚与双曲性

Ken'ichi Yoshida

AI总结 本文研究了织物的同胚性质和双曲性,通过图示确定织物的特征,并证明织物不存在本质的康伍尔球。

Comments 16 pages, 12 figures

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AI中文摘要

织物是一种由垂直和水平丝线组成的纺织品,通常具有周期性结构。在本文中,我们将织物视为厚ened torus中的链接,其图示由闭合测地线组成。主要结果是通过图示来表征织物的同胚和双曲性。此外,我们证明不存在织物的本质康伍尔球。我们使用织物补集的本质表面的正常位置来描述它们。

英文摘要

A weave is a type of textile that consists of vertical and horizontal threads, and typically it has a periodic structure. In this paper, we regard a weave as a link in the thickened torus with a diagram consisting of closed geodesics. As main results, we characterize isotopies and hyperbolicity of weaves to determine them from diagrams. Moreover, we show that there does not exist an essential Conway sphere for a weave. We use normal positions of essential surfaces of weave complements to describe them.

2605.22128 2026-05-22 cond-mat.supr-con cond-mat.str-el

Superconductivity in doped spin multimer systems

掺杂自旋多聚体系统的超导性

Ritsuki Hirabayashi, Masataka Kakoi, Ryota Ueda, Kazuhiko Kuroki, Tatsuya Kaneko

AI总结 研究探讨了在多自旋耦合系统中,即使在强结合能极限下,掺杂系统如何表现出超导性,并通过双Kondo晶格模型展示了这一现象,揭示了配对态在不同耦合强度下的稳定性及配对相关性的发展规律。

Comments 18 pages, 9 figures, 3 tables

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AI中文摘要

结合能,量化成对形成,是超导性出现的关键因素。在这里,我们展示即使多个自旋复杂耦合,掺杂系统可以映射到通用的硬核心玻色子模型,在强结合能极限下,表现出有希望的超导性迹象。我们通过双Kondo晶格模型分析和数值计算展示了这一概念。利用密度矩阵重整化群方法,我们表明即使在远离强耦合区域的参数下,配对态仍可通过交叉作用维持。此外,我们发现一旦结合能足够生成,配对相关性的发展与局部自旋相关性的细节无关。我们的发现为超导性研究提供了有用的指导方针。

英文摘要

Binding energy, which quantifies pair formation, is a key factor in the emergence of superconductivity. Here, we show that even when multiple spins are complexly coupled, hole-doped systems, which can be mapped onto the universal hardcore boson model in the strong-binding-energy limit, exhibit promising signatures of superconductivity. We analytically and numerically demonstrate this concept in the double Kondo lattice model. Using the density-matrix renormalization group method, we show that a pairing state is maintained via a crossover even for parameters away from the strong-coupling regime. Additionally, we find that once binding energies are sufficiently generated, pair correlations develop similarly regardless of the details of local spin correlations. Our findings suggest useful guidelines for research on superconductivity.

2605.22127 2026-05-22 math.GR math.RT

Twisted Frobenius-Schur Indicators and Character Degree Sums in Dihedral Groups

扭转的Frobenius-施图姆指示符与二面体群中的特征度数和

Venkata Subbaiah Yerrapati, Rahul Dixit, Ajay Kumar Shukla

AI总结 本文研究了有限群中特征度数和与扭转involution数量之间的关系,特别是在二面体群中证明了特征度数和大于等于所有自同构下的扭转involution数量。

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AI中文摘要

令G为有限群,T(G)表示其不可约复表示的度数之和。我们研究T(G)与自同构σ下的扭转involution数量m_σ=|{g∈G | σ(g)=g⁻¹}|之间的关系。尽管已知在某些情况下(例如实特征)T(G)=m_e对于恒等自同构e成立,但我们分析了非恒等自同构在群阶为p, 2p, p²的情况下的关系。我们证明对于二面体群D_n的族,对于所有σ∈Aut(D_n),不等式T(D_n)≥m_σ成立。我们利用数论性质对m_σ进行了完整分类。

英文摘要

Let $G$ be a finite group and $T(G)$ be the sum of the degrees of its irreducible complex representations. We investigate the relationship between $T(G)$ and the number of twisted involutions $m_σ= |\{g \in G \mid σ(g) = g^{-1}\}|$ for an automorphism $σ$. While it is known that $T(G) = m_e$ for the identity automorphism $e$ in certain cases (e.g., real characters), we analyze this relation for non-identity automorphisms of groups of order $p, 2p, p^2$. We prove that for the family of Dihedral groups $D_n$, the inequality $T(D_n) \geq m_σ$ holds for all $σ\in \mathrm{Aut}(D_n)$. We provide a complete classification of $m_σ$ using number-theoretic properties of the automorphism parameters.

2605.22125 2026-05-22 cond-mat.mtrl-sci

CNN-Based Classifier for Automated Identification of Magnetic States in Spin Dynamics Simulations

基于CNN的磁态自动识别分类器

Amal Aldarawsheh, Ahmed Alia, Stefan Blügel

AI总结 本文提出一种基于CNN的自动分类模型,用于识别和分类磁动力学模拟中的九种不同磁态,包括铁磁和反铁磁自旋纹理,如反铁磁Skyrmion和反铁磁条纹域。

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AI中文摘要

识别和分类不同的磁态对于理解磁性系统的复杂行为至关重要。传统方法依赖于手工特征或手动检查,往往在处理微妙或拓扑复杂的自旋纹理时表现不佳。在本研究中,我们提出了一种自动深度学习模型,该模型采用EfficientNetV1B0卷积神经网络来分类九种不同的磁态,包括铁磁(FM)和反铁磁(AFM)自旋纹理,如反铁磁Skyrmion和反铁磁条纹域。自旋配置通过原子自旋动力学模拟使用Spirit代码生成,然后通过VFRendering可视化生成RGB图像,作为分类模型的输入。

英文摘要

The identification and classification of different magnetic states are essential for understanding the complex behavior of magnetic systems. Traditional approaches that rely on handcrafted features or manual inspection often fall short, particularly when dealing with subtle or topologically complex spin textures. In this study, we present an automated deep learning model that employs an EfficientNetV1B0 Convolutional Neural Network to classify nine distinct magnetic states, including both ferromagnetic (FM) and antiferromagnetic (AFM) spin textures such as AFM skyrmions and AFM stripe domains. The spin configurations are generated through atomistic spin dynamics simulations using the Spirit code, then visualized with VFRendering to produce RGB images, which serve as inputs to the classification model.

2605.22118 2026-05-22 math.AG

On defective spans of singular vector tuples beyond the boundary format

关于超越边界格式的奇异向量元组缺陷张量空间

Ettore Teixeira Turatti, Emanuele Ventura

AI总结 本文研究了超越边界格式的张量空间,并分析一般临界空间是否与奇异向量元组的普遍张量空间一致。对于所有在任意因子数中超出边界格式一个的张量空间,将该张量空间在临界空间中的余维数与同调映射核的维数联系起来。此外,我们展示了一个无限阶数为三的张量的缺陷行为:一般奇异向量元组的张量空间达到最大可能余维数而非预期的最小值。最后,我们推测了该制度下临界空间行为的分类,并将其与Koszul上同调联系起来。

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AI中文摘要

在本文中,我们研究了超越边界格式的张量空间,并分析一般临界空间是否与一般奇异向量元组的张量空间一致。对于所有在任意因子数中超出边界格式一个的张量空间,我们将该张量空间在临界空间中的余维数与同调映射核的维数联系起来。此外,我们展示了一个无限阶数为三的张量的缺陷行为:一般奇异向量元组的张量空间达到最大可能余维数而非预期的最小值。最后,我们推测了该制度下临界空间行为的分类,并将其与Koszul上同调联系起来。

英文摘要

In this paper, we study tensor spaces beyond the boundary format and analyze whether the general critical space coincides with the general span of singular vector tuples. For all tensor spaces exceeding the boundary format by one in an arbitrary number of factors, we relate the codimension of this span within the critical space to the dimension of the kernel of a map in cohomology. Furthermore, we exhibit an infinite family of order-three tensors with a defective behavior: the general span of singular vector tuples achieves the maximum possible codimension rather than the expected minimum. Finally, we conjecture a classification of the behavior of critical spaces in this regime and draw a connection to Koszul cohomology.

2605.22117 2026-05-22 eess.SP

Beyond Spherical Wavefront: Near-Field Channel Estimation Under Wavefront Anisotropy

超越球面波前:考虑波前各向异性下的近场信道估计

Heling Zhang, Xiujun Zhang, Xiaofeng Zhong, Shidong Zhou

AI总结 本文针对存在近场曲面反射面时波前各向异性问题,提出了一种参数化模型和基于物理参数恢复的信道估计算法,验证了该算法在各向异性波前场景中的有效性。

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AI中文摘要

极大规模孔径阵列(ELAAs)和毫米波(mmWave)技术是实现未来无线通信系统高数据速率的关键。为了实现精确波束成形,这些系统需要准确的信道估计,其中必须考虑近场波前曲率效应。现有的信道估计方法依赖于球面波前信道(SWC)模型,该模型适用于具有点源、散射体和反射面的近场传播。然而,当存在近场曲面反射面时,反射波的波前变为各向异性而非球面,导致SWC模型不再准确。为了解决这个问题,本文提出了一种参数化模型用于各向异性波前信道(AWC)。基于该模型,我们提出了一种基于物理参数恢复的AWC信道估计算法。仿真结果表明,AWC在角度-距离域中不再保持稀疏性。此外,结果还展示了不同传播场景的物理特性如何影响波前各向异性程度,并验证了所提出算法在AWC场景中的有效性。

英文摘要

Extremely large aperture arrays (ELAAs) and millimeter-wave (mmWave) technologies are essential for achieving high data rates in future wireless communication systems. To perform precise beamforming, these systems require accurate channel estimation, in which the near-field wavefront curvature effect must be taken into account. Existing channel estimation methods rely on the spherical wavefront channel (SWC) model, which is suitable for near-field propagation with point sources, scatterers, and reflection planes. However, when a near-field curved reflecting surface exists, the wavefront of the reflected wave becomes anisotropic rather than spherical, causing the SWC model to become inaccurate. To address this problem, in this paper, we formulate a parameterized model for the anisotropic wavefront channel (AWC). Using this model, we propose a channel estimation algorithm based on physical parameter recovery for the AWC. Simulation results reveal that the AWC no longer retains sparsity in the angle-distance domain. Furthermore, the results demonstrate how different physical characteristics of the propagation scenario affect the degree of wavefront anisotropy, and confirm the effectiveness of our proposed algorithm in AWC scenarios.

2605.22116 2026-05-22 math.CO

Diagonal Ramsey numbers for wheels

轮图的对角Ramsey数

Maoxuan Li, Masaki Kashima, Yaping Mao

AI总结 本文研究了轮图的对角Ramsey数,改进了之前的结果,给出了更精确的上下界,并提供了关于k着色Ramsey数的递归界。

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AI中文摘要

Ramsey数R(G₁,G₂)是使得任何红蓝着色的完全图K_N的边中,包含一个红色G₁的副本或蓝色G₂的副本的最小整数N。2022年,第三作者等人给出了轮图W_n的Ramsey数R(W_n,W_n)的上下界。在本文中,我们改进了这些界,证明对于偶数n≥8,有3n-2≤R(W_n,W_n)≤6n-6;对于奇数n≥7,有2n≤R(W_n,W_n)≤(9n-7)/2。此外,我们还给出了轮图W_n的k着色Ramsey数的递归界。

英文摘要

The Ramsey number $\mathrm{R}(G_1,G_2)$ is the smallest integer $N$ such that any red-blue coloring of the edges of the complete graph $K_N$ contains either a red copy of $G_1$ or a blue copy of $G_2$. In 2022, the third author and others gave lower and upper bounds of the Ramsey number $\mathrm{R}(W_n,W_n)$, where $W_n$ is the wheel graph with $n$ vertices. In this paper, we improve their bounds by showing that $3n-2\leq \mathrm{R}(W_n,W_n)\leq 6n-6$ for even $n\geq 8$ and $2n\leq \mathrm{R}(W_n,W_n)\leq \frac{9n-7}{2}$ for odd $n\geq 7$. Furthermore, we give recursive bounds for the $k$-colored Ramsey number for $W_n$.

2605.22115 2026-05-22 math.NA cs.NA

Physics-Informed Neural Networks with Attention Feature Expansion for Monge-Ampère Equations

具有注意力特征扩展的物理信息神经网络用于Monge-Ampère方程

Anxiao Yu, Bangmin Wu, Zhengbang Zha, Xinlong Feng, Dongwoo Sheen

AI总结 本文提出了一种结合注意力特征扩展的物理信息神经网络(PINN-AFE),用于求解Monge-Ampère方程,通过多头注意力增强特征池实现自适应非线性特征表示,并采用输入凸神经网络保证解的严格凸性,同时结合动态加权损失函数和混合优化加速训练收敛,验证了该框架的准确性和计算效率,并将其扩展到图像处理任务中。

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AI中文摘要

Monge-Ampère方程是一个根本性的全非线性椭圆型偏微分方程,广泛应用于多个学科领域。本文提出了一种新的物理信息神经网络,结合注意力特征扩展(PINN-AFE),用于其数值求解。构建了多头注意力增强的特征池,以实现自适应的非线性特征表示,并采用输入凸神经网络来施加解的严格凸性,具有严格的理论保证。同时,制定了一种结合动态加权损失函数和混合优化的损失函数,以加速训练收敛。全面的数值实验验证了所开发框架的准确性和计算效率。PINN-AFE范式进一步扩展到图像处理任务中,在图像增强和医学图像配准场景中实现了高质量且物理一致的结果。

英文摘要

The Monge-Ampère equation is a fundamental fully nonlinear elliptic partial differential equation that finds extensive applications across multiple disciplines. This study proposes a novel physics-informed neural network integrated with attention feature expansion (PINN-AFE) for its numerical solution. A multi-head attention enhanced feature pool is constructed to enable adaptive nonlinear feature representation, and input convex neural networks are adopted to impose strict convexity of solutions with rigorous theoretical guarantees. Meanwhile, a dynamically weighted loss function combined with hybrid optimization is formulated to accelerate training convergence. Comprehensive numerical experiments validate the accuracy and computational efficiency of the developed framework. The PINN-AFE paradigm is further extended to image processing tasks, delivering high-quality and physically consistent results in both image enhancement and medical image registration scenarios.

2605.22113 2026-05-22 cs.CR

QT-PUF: Quantum Tunneling Leakage Based PUF for Implantable IoMT Devices

QT-PUF:基于量子隧穿泄漏的植入式IoMT设备物理不可克隆函数

Yueqi Ma, Vivek Mohan, Chip-Hong Chang, Emmanuel M. Drakakis

AI总结 本文提出了一种基于量子隧穿泄漏的物理不可克隆函数(PUF),用于植入式IoMT设备,通过利用标准CMOS器件过程中引起的量子机械门泄漏,实现低功耗、高安全性的设备身份验证。

Comments The paper has been accepted for presentation at the 2026 IEEE International Symposium on Circuits and Systems in Shanghai

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AI中文摘要

互联网医疗物联网(IoMT)标志着医疗保健向去中心化方向发展,通过连接的可穿戴和植入式设备实现持续监测和个性化护理。然而,确保这些设备自身的信任和完整性仍是一个重大挑战,因为物理入侵或伪造可能直接危及患者安全、隐私和数据完整性。本文提出了QT-PUF,一种基于门隧穿泄漏的物理不可克隆函数(PUF),利用标准CMOS器件中过程引起的量子机械门泄漏。提出了一种差分读出电路,其伪电阻I到V前端用于将皮安级泄漏变化转换为数字响应。与现有的基于内存、环振荡器或仲裁器的PUF不同,这些PUF在超低功耗IoMT设备中不太合适(由于额外的电路、功耗过高或稳定性差)。QT-PUF不需要外部激励或稳定,仅在静态偏置下运行。基于模拟测量的65nm CMOS工艺显示,其熵为0.9999998,FHD为0.5001,平均功率(能量)消耗为96.04nW/bit(19.21fJ/bit)在1.2V和35°C条件下。它在0.9-1.3V和0-100°C范围内可靠运行,平均误码率低于0.000163,在1.0-1.3V和10-70°C的运行条件下。

英文摘要

The Internet of Medical Things (IoMT) marks a shift toward decentralized healthcare, enabling continuous monitoring and personalized care through connected wearable and implantable devices. However, ensuring the trust and integrity of these devices themselves remains a major challenge, as physical compromise or counterfeiting can directly endanger patient safety, privacy, and data integrity. This work presents QT-PUF, a gate-tunneling-leakage-based physical unclonable function (PUF) that leverages quantum-mechanical gate leakage resulting from process-induced variations in standard CMOS devices. A differential readout circuit with a pseudo-resistor I-to-V frontend is proposed to convert the picoampere-level leakage variations into digital responses. Unlike existing PUFs such as those based on memory, ring oscillators, or arbiters, which are less suitable for ultralow-power IoMT devices (due to additional circuitry, power overhead, or poor stability), QT-PUF requires no external excitation or stabilization and operates under static bias. Simulation-based measurements for a $\mathbf{65}$~nm CMOS process demonstrate an entropy of $\mathbf{0.9999998}$, an FHD of $\mathbf{0.5001}$, and an average power (energy) consumption of $\mathbf{96.04}$~nW/bit ($\mathbf{19.21}$~fJ/bit, respectively) at $\mathbf{1.2\,V}$ and $\mathbf{35\,^{\circ}C}$ for the proposed PUF. It operates reliably across $\mathbf{0.9}\text{--}\mathbf{1.3}$~V and $\mathbf{0}\text{--}\mathbf{100\,^{\circ}C}$ with an average BER below $\mathbf{0.000163}$ across $\mathbf{1.0}\text{--}\mathbf{1.3}$~V and $\mathbf{10}\text{--}\mathbf{70\,^{\circ}C}$ within the operating conditions of typical implantable devices.

2605.22110 2026-05-22 stat.ME

Two-stage Ensemble Clustering of Functional Data Using Random Projections

基于随机投影的函数数据双阶段集成聚类

Sourav Chakrabarty, Anirvan Chakraborty, Shyamal K. De

AI总结 本文提出了一种基于高斯过程生成随机投影的函数数据聚类方法,通过两阶段聚类策略,利用均绝对距离度量进行高维数据聚类,并通过数据驱动的投影方向进一步优化聚类结果,验证了该方法在多种函数数据场景中的高准确性。

Comments 32 pages, 6 figures, 7 tables

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AI中文摘要

我们提出了一种计算上简单的框架,用于基于高斯过程生成的随机投影对函数数据进行聚类。在该方法中,每条曲线首先被投影到大量的独立高斯过程实现上。所得的高维表示通过均绝对距离度量(MADD)进行聚类,这是一种适合高维设置的不相似性度量。对这种不相似性的总体分析提供了随机投影如何捕捉功能群体之间分布差异的见解。我们引入了第二阶段的聚类,以进一步利用数据驱动的投影方向。因此,在第一阶段,使用一组预指定的投影家族获得初始聚类。在第二阶段,通过基于估计协方差算子构建的高斯随机投影对这一划分进行细化。最后,使用归一化成本函数在候选解中选择最佳聚类。所提出的聚类算法广泛适用于各种函数数据场景,包括不规则和部分观测数据。通过广泛的模拟和实际数据应用,我们证明所提出的方法在多种函数数据设置中实现了高准确性,并在许多最先进的方法中表现更优。

英文摘要

We propose a computationally simple framework for clustering functional data based on Gaussian-process-generated random projections. In this approach, each curve is first projected onto a large collection of independent Gaussian process realizations. The resulting high-dimensional representations are clustered using the Mean Absolute Difference of Distances (MADD), a dissimilarity measure well suited for high-dimensional settings. A population-level analysis of this dissimilarity provides insight into how random projections help capture distributional differences between functional populations. We introduce a second stage of clustering to additionally leverage on data-driven projection directions. Thus, in Stage I, an initial clustering is obtained using a set of prespecified projection families. In Stage II, this partition is refined by constructing Gaussian random projections based on an estimated covariance operator that uses the first stage of cluster labels. Finally, a normalized cost function is used to select the optimal clustering among candidate solutions. The proposed clustering algorithm is broadly applicable to diverse functional data regimes including irregular and partially observed data. Through extensive simulations and real-data applications, we show that the proposed method achieves a high degree of accuracy and outperforms many of the state-of-the-art methods across a wide range of functional data settings.

2605.22108 2026-05-22 hep-ph

MAcNLOPS for ZZ Pair Production at the LHC

MAcNLOPS 用于 LHC 中 ZZ 对产生

Yuxiao Che, Rikkert Frederix

AI总结 该研究提出在 MadGraph5_aMC@NLO + Pythia8 环境中实现 MAcNLOPS 匹配方案,用于 pp → ZZ 产生,通过移除负 H 事件并补偿 S 事件的第一 shower 发射来提高效率,验证了该方法在辐射敏感和包容双玻子可观测量上的准确性,展示了 MAcNLOPS 在减少负权重方面的优势。

Comments 10 pages

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AI中文摘要

我们提出了在 MadGraph5_aMC@NLO + Pythia8 环境中实现 MAcNLOPS 匹配方案用于 pp → ZZ 产生。从标准的 MC@NLO 事件样本出发,移除负 H 事件并通过对 S 事件的第一 shower 发射应用 veto 进行补偿。该实现通过与 MC@NLO 在辐射敏感和包容双玻子可观测量上的验证,发现其在非常低 pT 区域内的一致性达到相当小的幂抑制贡献。该方法能够有效移除所有负 H 权重,同时几乎不增加计算成本,而负 S 权重保持不变,表明 MAcNLOPS 是一种有前途的 MC@NLO 替代方法,具有更小的负权重比例。

英文摘要

We present an implementation of the MAcNLOPS matching prescription for $pp \to ZZ$ production in a MadGraph5_aMC@NLO + Pythia8 setup. Starting from a standard MC@NLO event sample, negative H events are removed and compensated by a veto applied to the first shower emission of the S events. The implementation is validated against MC@NLO for radiation-sensitive and inclusive diboson observables. Agreement is found up to a rather small power-suppressed contribution affecting the very low-pT region. The method removes all negative H weights with negligible additional computational cost, while negative S weights are left unchanged, showing that MAcNLOPS is a promising alternative to MC@NLO with a reduced fraction of negative weights.

2605.22107 2026-05-22 physics.flu-dyn

Full Turbulence Simulation of Channel Flow at $Re_τ \approx 1000$

湍流通道流在Re_τ≈1000时的全湍流模拟

Yoshinobu Yamamoto, Yoshiyuki Tsuji

AI总结 本文通过解析所有空间方向的Kolmogorov波数,对Re_τ≈1000的湍流通道流进行了全湍流模拟,揭示了中间层的物理意义宽度,并提供了高保真度的参考数据集,同时验证了在充分解析Kolmogorov长度尺度时,二阶中心差分方案在壁正方向上无不利数值影响,提出了两种分辨率标准以指导高雷诺数DNS模拟。

Comments 32 pages, 23 figures,

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AI中文摘要

通过解析所有空间方向的Kolmogorov波数,对湍流通道流在摩擦雷诺数(Re_tau)约为1000时进行了全湍流模拟(FTS)。在该雷诺数下,中间层达到具有物理意义的宽度,并在当前计算中完全解析,提供了捕捉其湍流和耗散特性的高保真度参考数据集。FTS的壁正网格间距还确认了,当Kolmogorov长度尺度被充分解析时,二阶中心差分方案在壁正方向上不引入不利的数值影响。在壁平行方向上,基于当前FTS确定了两种分辨率标准:一种是近似DNS分辨率,解析超过99%的湍流动能和耗散率(Delta x+约19,Delta y+约8,其中Delta x+和Delta y+表示壁单位下的流体方向和 spanwise 方向的分辨率);另一种是全耗散解析标准(Delta x+约7.5,Delta y+约5.0)。通过谱方法实现的近似分辨率能够以1%的精度再现基本湍流统计特性,仅需FTS中使用的网格点的八分之一,展示了其实际效率。相比之下,即使最高分辨率的二阶中心差分情况(Delta x+约5.0,Delta y+约4.5)也未能达到近似谱分辨率的精度。这些发现为高雷诺数DNS提供了重要的分辨率指南,特别是对于Re_tau=O(10^4)的模拟。

英文摘要

A Full Turbulence Simulation (FTS) of turbulent channel flow at friction Reynolds number (Re_tau) approx 1000 was performed by resolving the Kolmogorov wavenumber in all spatial directions. At this Reynolds number, the intermediate layer attains a physically meaningful width and is fully resolved in the present computation, providing the reference dataset that captures its turbulence and dissipation characteristics with high fidelity. The wall-normal grid spacing of the FTS also confirms that, when the Kolmogorov length scale is sufficiently resolved, the second-order central-difference scheme introduces no adverse numerical effects in the wall-normal direction. In the wall-parallel directions, two resolution criteria were identified based on the present FTS: a first-approximation DNS resolution that resolves more than 99 percent of the turbulent kinetic energy and dissipation rate (Delta x+ approx 19, Delta y+ approx 8, where Delta x+ and Delta y+ denote the streamwise and spanwise spatial resolutions in wall units) and a full dissipation-resolution criterion (Delta x+ approx 7.5, Delta y+ approx 5.0). The first-approximation resolution by means of a spectral method reproduces the essential turbulence statistics within 1 percent accuracy while requiring only one-eighth of the grid points used in the FTS, demonstrating its practical efficiency. In contrast, even the highest-resolution second-order central-difference case (Delta x+ approx 5.0, Delta y+ approx 4.5) fails to match the accuracy of the first-approximation spectral resolution. These findings provide important resolution guidelines for high-Reynolds-number DNS, particularly for simulations at Re_tau = O(10^4).

2605.22105 2026-05-22 physics.plasm-ph

On the Shafranov shift in stellarators

关于星形箍缩器中Shafranov位移的研究

Per Helander, Nikita Nikulsin

AI总结 本文提出了一种衡量Shafranov位移的平均方法,并讨论了其在不同优化星形箍缩器配置中的性质,显示在具有大量磁场周期的准螺旋和准等动力学星形箍缩器中,该位移特别小,因此对等离子体压力变化具有较强的鲁棒性。

Comments 15 pages, 7 figures. Submitted to Journal of Plasma Physics

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AI中文摘要

正如Shafranov首次所展示的,磁流体动力学平衡的托卡马克等离子体在压力增加时倾向于在主半径方向扩展。本文引入了一种衡量由此产生的Shafranov位移的平均量,并讨论了其在各种优化的星形箍缩器配置中的性质。结果显示,在具有大量磁场周期的准螺旋和准等动力学星形箍缩器中,该位移特别小,因此这些配置对等离子体压力的变化具有较强的鲁棒性。

英文摘要

As first shown by Shafranov, toroidal plasmas in magnetohydrodynamic equilibrium tend to expand in major radius when the pressure is increased. Here, an average measure of the resulting Shafranov shift is introduced, and its properties are discussed for various classes of optimised stellarator configurations. It is shown to be particularly small in quasi-helical and quasi-isodynamic stellarators with a large number of field periods, which are thus particularly robust to variations in the plasma pressure.

2605.22103 2026-05-22 cond-mat.stat-mech cond-mat.dis-nn

Berezinskii-Kosterlitz-Thouless-type Transition in Site Percolation on the Diamond Hierarchical Lattice

钻石分形晶格上位点渗流的Berezinskii-Kosterlitz-Thouless型相变

Takehisa Hasegawa, Kazuki Wataya, Tomoaki Nogawa

AI总结 研究了钻石分形晶格上的位点渗流,发现该晶格上的位点渗流在临界点附近表现出指数奇异性的相关长度,证明了有限维网络中可以出现临界相,而无需指数体积增长。

Comments 15 pages, 7 figures

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AI中文摘要

我们利用精确的生成函数分析研究了钻石分形晶格上的位点渗流,这是一种有限维的分形网络。与键渗流不同,该晶格上的位点渗流不经历从非渗流相到渗流相的相变。相反,系统在p < p_c时处于非渗流相,在p > p_c时处于临界相。在临界相中,最大团的尺寸保持亚扩展性,其规模为N^{ψ(p)},其中分形指数ψ(p)随p连续变化。通过分析临界点附近重整化群递归关系,我们证明相关长度表现出Berezinskii-Kosterlitz-Thouless型本质奇异性,ξ(p) ~ exp(const / sqrt(p_c - p)),当p → p_c^-时,这进一步通过有限尺寸标度分析得到验证,显示出出色的数列折叠。这些结果表明,即使在有限维网络中,临界相也可以出现,而指数体积增长并非必要。我们认为,钻石分形晶格上的临界相源于位点稀释在重整化下仍保持相关性。

英文摘要

We study site percolation on the diamond hierarchical lattice, a finite-dimensional fractal network, using an exact generating-function analysis. In contrast to bond percolation, site percolation on this lattice does not undergo a transition from a nonpercolating phase to a percolating phase. Instead, the system exhibits a nonpercolating phase for $p<p_{\rm c}$ and a critical phase for $p>p_{\rm c}$. In the critical phase, the size of the largest cluster remains subextensive, scaling as $N^{ψ(p)}$, where the fractal exponent $ψ(p)$ varies continuously with $p$. By analyzing the renormalization-group recursion relation in the vicinity of $p_{\rm c}$, we show that the correlation length exhibits a Berezinskii-Kosterlitz-Thouless-type essential singularity, $ξ(p)\sim \exp \left({\rm const}/\sqrt{p_{\rm c}-p}\right)$ for $p \to p_{\rm c}^-$, which is further confirmed by finite-size scaling analyses showing excellent data collapse. These results demonstrate that critical phases in percolation can emerge even on finite-dimensional networks and that exponential volume growth is not necessary for such phases to appear. We argue that the critical phase on the diamond hierarchical lattice stems from site dilution remaining relevant under renormalization.

2605.22094 2026-05-22 physics.comp-ph cond-mat.mtrl-sci

A path-finding algorithm for computing minimal-weight-matching centrosymmetry parameter

计算最小权匹配中心对称参数的一种路径寻找算法

Vasily V. Pisarev

AI总结 本文提出了一种基于路径寻找和A*算法的替代方法,用于计算最小权匹配中心对称参数,以改进现有分子动力学分析软件中该参数计算方法的不足。

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AI中文摘要

在2020年,Peter Larsen指出现有分子动力学和分析软件中计算中心对称参数的方法存在缺陷。他提出了一种直观且数学上严谨的公式,将中心对称参数表示为完全连接原子邻居图上的最小权匹配(MWM)的函数。他建议使用Edmonds的blossom算法来计算此类匹配。在本文中,我们研究了一种替代方法,使用路径寻找方法和A*算法来计算MWM CSP。

英文摘要

In 2020, Peter Larsen reported flaws in the methods for centrosymmetry parameter computation in the existing molecular dynamics and analysis packages. He proposed an intuitive an mathematically rigorous formulation for centrosymmetry parameter in terms of minimal-weight matching (MWM) on a fully-connected graph of atomic neighbors. He proposed using Edmonds' blossom algorithm for computing such a matching. In this paper, we investigate an alternative algorithm for MWM CSP computation using path finding approach and A* algorithm.

2605.22091 2026-05-22 cs.HC

Narrative Sharpens Gender Gaps: Surveying Film Characters with LLM Agents

叙述强化性别差距:用LLM代理调查电影角色

Vivienne Bihe Chi, Reyhan Jamalova, Lyle Ungar, Sharath Chandra Guntuku

AI总结 本文提出一种框架,通过LLM代理调查电影角色,揭示叙述如何强化性别差异,而非同质化,挑战了传统培养理论的假设。

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AI中文摘要

主流电影是AI系统学习的最丰富的文化内容之一。然而,我们缺乏测量其编码性别价值观的工具。我们提出一个概念验证框架,将虚构电影角色转化为可调查的LLM代理。使用160部美国电影(1990-2019年),我们从剧本对话和场景描述中构建了734个角色代理,通过专家式反思浓缩其人格,并模拟世界价值观调查的性别态度响应。代理在没有显式人口统计提示的情况下再现系统性的性别差异,表明态度源于行为而非身份标签。与历史调查数据相比,代理夸大了性别差距,并显示出比真实人口更大的年代间波动性。叙述强化而非同质化性别对比,复杂了培养理论主流机制背后的稳定输入假设。此类语料库训练的AI系统可能在任何模型级放大之前继承这种风格化。

英文摘要

Mainstream film is one of the richest sources of cultural content that AI systems learn from. Yet we have few tools for measuring the gender values it encodes. We present a proof-of-concept framework that turns fictional film characters into surveyable LLM agents. Using 160 U.S. films (1990--2019), we build 734 character agents from script dialogue and scene descriptions, condense their personas via expert-style reflections, and simulate World Values Survey gender-attitude responses. Agents reproduce systematic gender differences without explicit demographic prompting, suggesting attitudes emerge from behavior rather than identity labels. Benchmarked against historical survey data, agents exaggerate gender gaps and show greater decade-to-decade volatility than real populations. Narrative sharpens rather than homogenizes gender contrasts, complicating the consistent-input assumption underlying cultivation theory's mainstreaming mechanism. AI systems trained on such corpora may inherit this stylization before any model-level amplification occurs.

2605.21438 2026-05-22 math.PR math-ph math.MP

A random walk approach to high-dimensional critical phenomena

通过随机游走方法研究高维临界现象

Hugo Duminil-Copin, Aman Markar, Romain Panis, Gordon Slade

AI总结 本文通过随机游走技术,证明了在高维空间中,满足特定假设的函数在近临界行为下的均场特性,适用于自避游走、渗透、自旋(Ising、XY、|φ|^4)和晶格树等模型。

Comments 85 pages, 7 figures. Corrected a typo in the abstract

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AI中文摘要

我们为一系列定义在$\mathbb Z^d$(${d>2}$)上的函数提供了一个“黑箱”证明,证明了这些函数在亚临界或临界状态下具有衰减形式$|x|^{-d+2+\varepsilon}\exp[-c|x|/ξ]$,对于任何$\varepsilon>0$。该黑箱方法适用于多个模型,其中常见的方法可以用来验证假设。应用包括自避游走、渗透、自旋(Ising、XY、$|φ|^4$)和晶格树等模型,这些模型均在其上临界维度以上。证明基于随机游走技术,提供了一个新的、统一的、概率性的且相对简单的均场近临界行为证明。

英文摘要

We present a "black box" proof of mean-field near-critical behaviour for a family of functions on $\mathbb Z^d$ (${d>2}$) satisfying a short list of assumptions. The functions represent two-point functions of a lattice statistical mechanical model in the subcritical or critical regimes, and are proved to have decay of the form $|x|^{-d+2+\varepsilon}\exp[-c|x|/ξ]$, for any $\varepsilon>0$. The black box applies to several models for which commonplace methods can be used to verify the assumptions. Applications include models of self-avoiding walk, percolation, spins (Ising, XY, $|φ|^4$), and lattice trees, all above their upper critical dimensions. The proof is based on random walk techniques, and provides a new, unified, probabilistic, and relatively simple proof of mean-field near-critical behaviour.

2605.21397 2026-05-22 cs.SE

Validating Navmesh using Geometry: Voxel-Based Analysis with Prioritized Exploration

通过几何验证导航网格:基于体素的分析与优先探索

Ramesh Raghavan, Ojas Sharma, Sebastien Larrue, Alan Isaac Kunder, Aakash Sai, Rishi Mathur

AI总结 本文提出了一种通过独立的几何驱动分析来验证导航网格正确性的框架,通过基于体素的表示直接从环境几何重建可行走空间,并利用约束感知的遍历和连通性评估进行验证,采用优先搜索问题解决体素空间中的不一致区域,通过比较体素表示和导航网格的可达性来检测导航问题。

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AI中文摘要

导航网格(Navmesh)的不一致会直接影响游戏环境中非玩家角色(NPC)所使用的导航系统,从而影响玩家体验。虽然导航网格是通过世界几何使用已建立的算法生成的,但开发过程中环境会不断变化,地形被调整,资产被移动或替换,导致导航网格与实际环境之间出现不匹配。现有的自动化方法尝试通过探索代理和强化学习技术来检测导航问题。然而,由于这些方法依赖于导航数据本身或间接评估导航行为,它们并没有明确验证导航表示是否反映了由底层几何定义的可行走空间。本文提出了一种通过独立的几何驱动分析来验证导航网格正确性的框架。该方法通过基于体素的表示直接从环境几何重建可行走空间,随后进行约束感知的遍历和连通性评估。验证被形式化为体素空间上的优先搜索问题,其中强化学习指导采样向更可能表现出不一致性的区域。在每个采样位置,从体素表示中推导出的可达性与通过引擎级查询从导航网格中获得的可达性进行比较。在多个大型开放世界游戏环境中的实验表明,该方法能够一致地降低探索努力,同时保持相似的缺陷检测覆盖率。该框架在游戏引擎中离线运行,并可以集成到自动化质量保证流程中。由于该方法依赖于几何,因此可以跨游戏引擎进行适应,只需最小的修改,使其适合生产部署。

英文摘要

Navigation mesh (Navmesh) inconsistencies affect the player experience by directly impacting the navigation systems used by non-playable characters (NPCs) in game environments. While navmeshes are generated from world geometry using well-established algorithms, environments change throughout development as terrain is adjusted and assets are moved or replaced, resulting in mismatches between the navmesh and the actual environment. Existing automated approaches attempt to detect navigation issues using exploration agents and reinforcement learning techniques. However, since these methods rely on the navigation data itself or evaluate navigation behavior indirectly, they do not explicitly verify whether the navigation representation reflects the walkable space defined by underlying geometry. This paper presents a framework for validating navigation meshes through an independent, geometry-driven analysis of navmesh correctness. The approach reconstructs walkable space directly from environment geometry using a voxel-based representation, followed by constraint-aware traversal and connectivity evaluation. Validation is formulated as a prioritized search problem over the voxel space, where reinforcement learning guides sampling toward regions more likely to exhibit inconsistencies. At each sampled location, reachability derived from the voxel representation is compared against reachability obtained from the navmesh via engine-level queries. Experiments across multiple large-scale open-world game environments show that the approach consistently lowers exploration effort while maintaining similar defect detection coverage. The framework runs offline within the game engine and can be integrated into automated quality assurance pipelines. Since the method relies on geometry, it can be adapted across game engines with minimal changes, making it suitable for production deployment.

2605.21378 2026-05-22 cs.CR cs.CY

Auditing Apple's DifferentialPrivacy.framework: Implementation Bugs, Misconfigurations, and Practical Risks

对Apple的差分隐私框架进行审计:实现错误、配置错误和实际风险

Rishav Chourasia, Ergute Bao, Uzair Javaid, Xiaokui Xiao

AI总结 本文对Apple的差分隐私框架进行了客户端审计,发现多个实现错误和配置错误,导致多个机制未能满足其宣称的隐私保证,影响了大量数据收集。

Comments 19 pages, 9 figures, 1 table. Accepted at the 47th IEEE Symposium on Security and Privacy (IEEE S&P 2026); Distinguished Paper Award

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Journal ref
Proceedings of the 47th IEEE Symposium on Security and Privacy (IEEE S&P), 2026
AI中文摘要

自2016年以来,Apple声称用于改进用户体验的设备分析数据受到差分隐私(DP)保护。Apple的差分隐私框架被部署在其操作系统中,处理敏感信号,如Safari域名、键盘事件、照片属性和健康报告。由于Apple未开源其隐私算法,这些隐私声明难以独立验证。我们对Apple的DP框架在macOS Sonoma 14.2和Sequoia 15.6上进行了客户端审计。我们逆向工程已发货的二进制文件,恢复Objective-C接口,构建运行时Harnesses来执行Apple部署的机制,并测试其输出是否符合所宣传的隐私保证。我们的审计涵盖了几乎所有活跃部署的机制,包括Count Median Sketch、Hadamard-CMS、随机响应机制和Prio风格的安全聚合。我们发现多个实现错误和配置错误。每一个依赖于浮点噪声的审计机制都未能满足其宣称的DP或零知识证明保证,因为存在已知的浮点漏洞的不安全采样器。我们还发现安全聚合配置中禁用了本地DP,使任何访问这些日志的方都能获取预聚合记录。总体而言,我们发现9个审计机制中有5个存在DP违规,影响了macOS Sonoma中87%的数据收集和Sequoia中68%的数据收集。我们还识别出公开泄露的iPhone日志,可以解码以恢复私人信息,包括Safari域名和键盘表情符号信号。

英文摘要

Since 2016, Apple has claimed that device analytics collected to improve user experience are protected by differential privacy (DP). Apple's DifferentialPrivacy framework is deployed across its operating systems and handles sensitive signals such as Safari domains, keyboard events, photo attributes, and health-related reports. Because Apple has not open-sourced its privatization algorithms, these privacy claims have been difficult to verify independently. We present a client-side audit of Apple's DP framework on macOS Sonoma 14.2 and Sequoia 15.6. We reverse engineer the shipped binaries, recover Objective-C interfaces, build runtime harnesses that execute Apple's deployed mechanisms, and test whether their outputs match the advertised privacy guarantees. Our audit covers nearly all active deployed mechanisms, including Count Median Sketch, Hadamard-CMS, randomized-response mechanisms, and Prio-style secure aggregation. We find multiple implementation bugs and misconfigurations. Every audited mechanism that relies on floating-point noise fails to meet its advertised DP or zero-knowledge proof guarantee, due to insecure samplers with known floating-point vulnerabilities. We also find secure-aggregation configurations with local DP disabled, exposing pre-aggregation records to any party with access to those logs. Overall, we find DP violations in 5 of 9 audited mechanisms, affecting 87% of data collection in macOS Sonoma and 68% in Sequoia. We also identify public leaked iPhone logs that can be decoded to recover private information, including Safari domains and keyboard emoji signals.

2605.21236 2026-05-22 astro-ph.SR

The Beauty of k2: Probing Stellar Interiors Using Apsidal Motion. I. The Benchmark Massive Binary HD 152248

k2之美:利用轨道进动探测恒星内部。I. 标准质量大双星HD 152248

Sophie Rosu, Luca Sciarini, Sylvia Ekström, Patrick Eggenberger, Joris Josiek, Raphael Hirschi, Cyril Georgy

AI总结 通过研究HD 152248双星的轨道进动,作者利用恒星内部结构常数k2来约束大质量恒星的内部密度分层和对流边界混合,揭示了k2偏差问题及内部混合机制的复杂性。

Comments Accepted for publication in Astronomy & Astrophysics Change from previous version: list of authors updated

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AI中文摘要

在过去的几十年里,多个独立研究显示,为了再现大质量恒星的各种观测特性,需要大量的对流边界混合(CBM)和对流核心尺寸。然而,比20个太阳质量更重的恒星缺乏CBM的定量处方以及内部混合机制的明确约束。我们利用双星HD152248中观测到的轨道进动——与恒星内部结构常数k2相关——来约束大质量恒星的内部密度分层和CBM。我们构建了GENEC恒星模型,假设两种不同的角动量传输:纯流体动力学(hydro)和磁扩散(magnetic)。我们将单星和双星模型进行比较,以评估潮汐锁定对恒星演化的冲击。我们研究了CBM(超流)、金属丰度、初始氦丰度和质量、质量损失率以及混合长度参数对恒星参数演化的冲击。我们指出模型中的k2值系统性地大于观测值,即所谓的k2偏差。模型预测恒星核心与外部层之间的密度对比过低。无论是流体动力学还是磁扩散模型,都需要1.2的较大超流来再现恒星参数,包括k2。其他参数几乎无影响。鉴于潮汐对同步系统的效率,伪同步假设对本系统是合理的。它设定了恒星自转轴偏转角的上限约为50度。即使有如此意外大的角度,k2偏差仍未得到解决。即使质量损失率被低估了一倍,对恒星参数的演变也没有影响,包括k2。这表明轨道进动是探测恒星内部的强大、稳健的方法。

英文摘要

Over the last decades, several independent studies have shown the need for large convective boundary mixing (CBM) and convective core sizes in massive stars to reproduce a variety of their observed properties. Yet, stars more massive than 20Msun lack a quantitative prescription for CBM as well as an unequivocal constraint on the internal mixing mechanisms acting in them. We use the apsidal motion observed in the twin binary HD152248 - linked to the internal stellar structure constants k2 of the stars - to constrain massive stars' internal density stratification and CBM. We build GENEC stellar models assuming two different angular momentum transports: purely hydrodynamic (hydro) and magneto-diffusive (magnetic). We confront single- and binary-star models to assess the impact of tidal locking on the star's evolution. We investigate the impact of CBM (overshooting), metallicity, initial helium abundance and mass, mass-loss rate, and mixing length parameter on the evolution of stellar parameters. We highlight that k2 from the models are systematically larger than observed ones, the so-called k2-discrepancy. Models predict stars with too low a density contrast between their core and external layers. Both hydro and magnetic models require large step-overshoot of 1.2 to reproduce stellar parameters, including k2. Other parameters have almost no impact. Given the efficiency of tides to synchronise systems, the assumption of pseudo-synchronisation is sound for this system. It sets an upper limit on the misalignment angle of stellar rotation axes of ~50°. Even with such unexpected large angles, the k2-discrepancy is not solved. Even if the mass-loss rate was underestimated by a factor two, it would have no impact on stellar parameters evolution, including k2. It demonstrates that the apsidal motion is a powerful, robust means to probe stellar interiors.

2605.21169 2026-05-22 math.OC

Decentralized Inexact Cubic Newton Method with Consensus Procedure

去中心化近似三次牛顿法与共识过程

Artem Agafonov, Anton Novitskii, Alexander Rogozin, Yury Sokolov, Dmitry Kamzolov, Alexander Dyakonov, Martin Takáč, Alexander Gasnikov

AI总结 本文研究了去中心化的二次优化问题,提出了一种适用于凸优化的去中心化三次牛顿方法,并开发了能够准确跟踪共识和局部迭代不一致性的理论。该方法在L1梯度光滑性和L2Hessian Lipschitz连续性假设下,与精确三次牛顿方法具有相同的迭代复杂度,并通过额外的多项式对数通信轮次开销达到所需的共识精度。此外,还提出了适用于强凸目标的加速去中心化三次牛顿方法,其迭代复杂度与精确加速三次牛顿方法一致。最后,尽管通用方法需要交换完整的d×dHessian矩阵,但通过仅传输向量的方式实现了在高维情况下更实用的实现。

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AI中文摘要

分布式优化广泛应用于大规模和隐私保护机器学习中,其中每个代理存储局部目标并仅与其邻居在连接网络中通信。我们研究了去中心化的二次优化,并专注于通过邻居间通信近似平均局部迭代、梯度和Hessian的共识过程。我们提出了一种适用于凸优化的去中心化三次牛顿方法,假设梯度的L1光滑性和Hessian的L2Lipschitz连续性,并开发了能够准确跟踪由共识和局部迭代不一致引起的不准确性的理论。在这些假设下,该方法与精确三次牛顿方法具有相同的迭代复杂度,并仅需额外的多项式对数通信轮次开销以达到所需的共识精度。我们进一步提出了适用于强凸目标的加速去中心化三次牛顿方法,并证明其迭代复杂度与精确加速三次牛顿方法一致,同样仅需额外的多项式对数通信轮次开销。最后,尽管通用方法需要交换完整的d×dHessian矩阵,但通过仅传输向量的方式实现了在高维情况下更实用的实现。

英文摘要

Distributed optimization is widely used in large-scale and privacy-preserving machine learning, where each agent stores a local objective and communicates only with its neighbors in a connected network. We study decentralized second-order optimization and focus on consensus procedures that approximately average local iterates, gradients, and Hessians through neighbor-to-neighbor communications. We propose a general Decentralized Cubic Newton method for convex optimization under $L_1$-smoothness of gradients and $L_2$-Lipschitz continuity of Hessians, and develop a theory that accurately tracks the inaccuracies caused by consensus and by disagreement between local iterates. Under these assumptions, the method matches the iteration complexity of the exact Cubic Newton method and requires only additional polylogarithmic communication-round overhead to reach the necessary consensus accuracy. We further propose an Accelerated Decentralized Cubic Newton method for strongly convex objectives and show that it matches the iteration complexity of the exact Accelerated Cubic Newton method, again with only additional polylogarithmic communication-round overhead. Finally, although the general method requires exchanging full $d \times d$ Hessian matrices, we show how it can be implemented for generalized linear models by transmitting only vectors, making the approach substantially more practical in high dimensions.

2605.20857 2026-05-22 quant-ph

Decoy State based Time Synchronization

基于诱骗态的时间同步

Lukas Tiefenthaler, Hannah Thiel, Davide Rusca, Antia Lamas Linares

AI总结 本文研究了利用已存在于诱骗态BB84协议中的信号进行时间同步的可能性,无需修改协议,仅通过不同平均光子数的信号和诱骗态实现时间同步,简化了QKD系统的实现。

Comments to be published

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Journal ref
Optics Express 2026
AI中文摘要

时间同步是量子密钥分发(QKD)协议中的关键要求,确保通过正确分配原始密钥的位进行准确的密钥生成,并通过精确记录光子统计实现窃听检测。最先进的实验通常使用额外的通道通过经典信号来同步发射端和接收端的时钟。在本文中,我们研究了通过用于密钥生成的信号进行时间同步的可行性,这些信号已经存在于诱骗态BB84协议中。无需对协议进行任何修改,我们利用信号和诱骗态的不同平均光子数进行时间同步,而无需专用的能够进行时钟同步的物理通道。所提出的方法仅依赖于用于密钥生成的发送和接收光子,而不需要对QKD协议进行任何更改。实验中的唯一变化是在软件层面,因此实现起来非常简单。我们在特定光纤基QKD实验的模拟中展示了时间同步方法。与其他诱骗态BB84协议一样,它基于弱相干脉冲。在该模拟中,我们研究了参数空间以找到我们提出的方法的限制和最佳选择。除了非协议修改的时间同步方法外,我们还讨论了一种通过引入一个具有非常高平均光子数的额外诱骗态来显著提高在高损耗信道中性能的方法。通过消除对专用时钟同步通道的需求,这两种方法可能减少QKD系统的复杂性和成本,并提高其敏捷性。

英文摘要

Time synchronization is a crucial requirement in quantum key distribution (QKD)8 protocols, ensuring accurate key generation via the correct assignment of bits of raw key and9 enabling eavesdropping detection via the precise recording of photon statistics. State-of-the-art10 experiments typically use an extra channel to synchronize the clocks of the transmitter and receiver11 via classical signals. In this work, we study the possibility of performing clock synchronization12 via the signals used for the key generation, which are already present in decoy-state-based BB8413 protocols.14 Without altering the protocol in any way, we use the different mean photon numbers of the15 signal and decoy states for time synchronization without a dedicated physical channel capable of16 clock synchronization. The proposed method relies only on the photons sent and received for17 key generation and does not require any change to the QKD protocol. The only change in the18 experiment is on the software level, thus making it very simple to implement.19 We demonstrate clock synchronization method in a simulation of a specific fiber-based QKD20 experiment. Like other decoy-state-based BB84 protocols, it is based on weak coherent pulses.21 In this simulation, we investigate the parameter space to find limits and optimal choices of our22 proposed method.23 In addition to the non-protocol-altering clock synchronization method, we also discuss an24 approach that significantly improves performance in lossy channels by introducing an additional25 decoy state with a very high mean photon number.26 By eliminating the need for an extra channel capable of clock synchronization, both methods27 proposed potentially reduce the complexity and cost of QKD systems and improve their agility

2605.20754 2026-05-22 math.AG

Optimal bend-and-break for foliations

叶面的最优弯折-破裂

Jihao Liu, Zeming Sun, Jiedong Jiang

AI总结 本文研究了叶面的最优弯折-破裂常数,证明了对于正常投影概形上的秩为r的叶面,弯折-破裂不等式中最优常数为r+1,结合了Bogomolov-McQuillan方法和Jovinelly-Lehmann-Riedl发展出的弯折-破裂方法,并大量使用了生成式人工智能,特别是Rethlas系统。

Comments 20 pages. AI-generated, human verified

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AI中文摘要

我们证明,对于每一个秩为r的叶面F在正常投影概形上的最优常数在切有理曲线的弯折-破裂不等式中为r+1。证明结合了Bogomolov-McQuillan方法和Jovinelly-Lehmann-Riedl发展出的弯折-破裂方法。本文主要结果的证明很大程度上使用了生成式人工智能,特别是Rethlas系统。

英文摘要

We show that for every foliation $\mathcal{F}$ of rank $r$ on a normal projective variety, the optimal constant in the bend-and-break inequality for tangent rational curves is $r+1$. The proof combines the method of Bogomolov--McQuillan and the bend-and-shatter method developed by Jovinelly--Lehmann--Riedl. The proof of the main result of this paper substantially uses generative AI, particularly the Rethlas system.

2605.20517 2026-05-22 cond-mat.mes-hall cond-mat.mtrl-sci

Coexisting Ballistic and Diffusive Heat Transport in Micrometer-Long Molecular Junctions

在微米级分子结中共存的球形热传输和扩散热传输

P. M. Martinez, O. Mateos-Lopez, J. C. Cuevas, J. G. Vilhena

AI总结 研究揭示了在微米级分子结中,热传导既存在球形传输也存在扩散传输的现象,通过原子级模拟发现热传导不收敛,且在长程尺度下呈现L^(1/3)的发散行为,揭示了低频声子的非热化机制。

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AI中文摘要

玻尔兹曼输运理论,作为预测热导率的标准框架,假设每个振动模式最终都会散射,获得有限寿命,从而产生收敛且与长度无关的热导率:傅里叶定律。在这里,我们证明这一假设在真实分子系统中不成立。通过原子级模拟了长度跨度达五个数量级(0.5纳米到4微米)的金-烷烃-金单分子结,发现热导率从未收敛。在室温下,传输在一百纳米内为球形传输,比现有单分子测量扩展近两个数量级。在此窗口之后,导电性以L^(1/3)发散,这是Kardar-Parisi-Zhang普遍性类为动量守恒系统预测的尺度。对热流的频率分解揭示了发散背后的机制。低频声学模式从未热化:受动量守恒保护,它们在每一个链长中仍保持球形传输,仍然在L=2微米时携带总热流的50%。所有其他模式随着长度增加集体热化,作为离散振动状态合并到散射活跃的声子带中。因此,发散的导电性源于这两种共存传输区域之间的边界:随着L的增长,散射的起始点逐渐向低频移动,抑制球形通道的速度,维持L^(1/3)的发散,使每个长度都留下有限的贡献。这种永久球形传输和良好行为扩散传输的共存,预期在抽象的一维晶格模型中出现,但在真实微米级结的结构和化学复杂性中得以存活。

英文摘要

Boltzmann transport theory, the standard framework for predicting thermal conductivity, assumes that every vibrational mode eventually scatters, acquiring a finite lifetime that yields a convergent, length-independent thermal conductivity: Fourier's law. Here we show that this assumption fails in a real molecular system. Through atomistic simulations of Au-alkane-Au single-molecule junctions spanning five orders of magnitude in length (0.5 nm to 4 $μ$m), we find that thermal conductivity never converges. Transport is ballistic for up to one hundred nanometers at room temperature, extending nearly two orders of magnitude beyond existing single-molecule measurements. Past this window, conductivity diverges as $L^{1/3}$, the scaling predicted by the Kardar-Parisi-Zhang universality class for momentum-conserving systems. Frequency-resolved decomposition of the heat current reveals the mechanism behind the divergence. Low-frequency acoustic modes never thermalize: protected by momentum conservation, they remain ballistic at every chain length, still carrying 50% of the total heat current at $L = 2 μ$m. All other modes thermalize collectively as discrete vibrational states merge into scattering-active phonon bands with increasing length. Hence, the diverging conductivity emerges from the boundary between these coexisting transport regimes: as $L$ grows, the onset of scattering shifts progressively toward lower frequencies, suppressing the ballistic channel at a rate that sustains the $L^{1/3}$ divergence, leaving a finite contribution at every length. This coexistence of permanent ballistic and well-behaved diffusive transport, anticipated in abstract one-dimensional lattice models, survives the structural and chemical complexity of real micrometer-sized junctions.

2605.20305 2026-05-22 physics.pop-ph astro-ph.IM

The Era of Extremely Large Optical Telescopes: The ELT

超大光学望远镜时代:ELT

Priya Hasan

AI总结 本文探讨了超大光学望远镜(ELT)的出现及其对天文观测的深远影响,重点介绍了ELT的关键技术突破及其在光谱分析、系外行星大气研究和早期宇宙探索中的科学贡献。

Comments Submitted to Resonance

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AI中文摘要

超大光学望远镜(ELT)的出现标志着地面光学或红外天文台的主要镜面超过20米,预示着天文观测的一个变革性时代。本文探讨了这一新时代的开端,并介绍了三个即将建成的光学红外望远镜:巨人魔杖望远镜(GMT)、三十米望远镜(TMT)和欧洲极大望远镜(ELT)。本文将重点介绍ELT,后续文章将涵盖GMT和TMT。我们描述了其建设的关键技术突破,特别是分段镜设计、先进的自适应光学(AO)和激光引导星系统。这些创新将使光收集面积和空间分辨率提升一个数量级,提供比空间望远镜更清晰的宽视场图像。ELT的科学影响深远而多样。我们讨论了其起源和建设里程碑,并探讨了其在直接成像和表征类地系外行星大气、寻找生物标记物以及追踪最早恒星、星系和超大质量黑洞形成中的潜力。本文结论认为,ELT并非仅仅是小幅改进,而是基础性仪器,将重新定义天体物理学的前沿,回答科学最持久的问题,并不可避免地带来超出当前预测的发现。

英文摘要

The advent of Extremely Large Telescopes ELTs, ground-based optical or infrared observatories with primary mirrors exceeding 20 m heralds a transformative epoch in observational astronomy. This article examines the dawn of this new era and the three upcoming facilities in the optical infrared band the Giant Magellan Telescope GMT, the Thirty Meter Telescope TMT, and the European Extremely Large Telescope ELT. This article will focus on the ELT, while a sequel will cover GMT and TMT. We describe the key technological breakthroughs enabling its construction, most notably the segmented mirror design, advanced adaptive optics AO, and laser guide star systems. These innovations will deliver more than an order of magnitude leap in light-gathering area and spatial resolution, providing image sharpness exceeding that of spacebased telescopes for widefield observations. The scientific impact of the ELT is profound and multifaceted. We discuss its inception and construction milestones and explore its potential to directly image and characterize the atmospheres of Earth like exoplanets, searching for biosignatures, and trace the formation of the first stars, galaxies, and supermassive black holes. This paper concludes that ELTs are not mere incremental improvements but foundational instruments that will redefine the frontiers of astrophysics, address some of science's most enduring questions, and inevitably lead to discoveries beyond current prediction.

2605.19874 2026-05-22 physics.chem-ph

FNO-CCSDTQ(5)$_Λ$ as an economical alternative for connected quintuple excitations contributions in coupled cluster thermochemistry

FNO-CCSDTQ(5)Λ作为连接五重激发贡献在耦合簇热化学中的经济替代方案

Gregory H. Jones, Aditya Barman, Margarita Shepelenko, Jan M. L. Martin

AI总结 本文提出了一种经济的替代方法,利用FNO-CCSDTQ(5)Λ来计算耦合簇理论中连接五重激发贡献,在热化学计算中具有重要性,尽管计算成本高,但通过冻结自然轨道展开可实现快速收敛。

Comments to be submitted, 7 pages in AIP two-column format [minor updates]

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AI中文摘要

耦合簇理论中连接五重激发的贡献可以达到0.5 kcal/mol范围,这对于精确的热化学计算来说是重要的,然而,计算时间随N增长的比例为N^12,这阻碍了常规评估。我们展示,对于五重激发的微分贡献,冻结自然轨道(FNO)展开相对于NO截断的收敛性足够快,使得截断为0.0025或0.001的FNO-CCSDTQ(5)Λ成为可行的替代方案。从{0.005, 0.0025}进行简单外推到零截断,作为低成本选项出人意料地有效。有趣的是,FNO收敛性对于第二行化合物比第一行化合物更慢。

英文摘要

Contributions from connected quintuple excitations in coupled cluster theory can reach the 0.5 kcal/mol range, important enough to matter in accurate computational thermochemistry, yet the very steep $\propto N^{12}$ CPU time scaling impedes routine evaluation. We show that for the differential contribution of quintuples, convergence of a frozen natural orbital (FNO) expansion with respect to the NO cutoff is rapid enough to make FNO-CCSDTQ(5)$_Λ$ with cutoffs of 0.0025 or 0.001 viable alternatives. A naive extrapolation to zero cutoff from \{0.005,0.0025\} works surprisingly well as a low-cost option. Interestingly, FNO convergence is definitely slower for second-row than for first-row compounds.

2605.19863 2026-05-22 math.KT math.AT math.OA

$E$-theory of $X$-$C^{*}$-algebras and functor formalisms

$E$-theory of $X$-$C^{*}$-algebras and functor formalisms

Ulrich Bunke

AI总结 本文研究了局部紧 Hausdorff 空间上的 $E$-理论作为六 functor 形式化,并证明其等价于 $E$-valued sheaves 的六 functor 形式化,同时展示了可表示为有限开子 locale 联合的 locale 的 $E$-理论范畴等价于 $E$-valued cosheaves 的范畴。

Comments 96p, small correction: (missing $A$-bilinearity condition in Prop. 5.4 added)

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AI中文摘要

We show that $E$-theory for locally compact Hausdorff spaces constitutes a six-functor formalism which is equivalent to the six-functor formalism of $\mathrm{E}$-valued sheaves. We furthermore show that the $E$-theory category for locales that can be written as unions of finite open sublocales is equivalent to the category of $\mathrm{E}$-valued cosheaves.

英文摘要

We show that $E$-theory for locally compact Hausdorff spaces constitutes a six-functor formalism which is equivalent to the six-functor formalism of $\mathrm{E}$-valued sheaves. We furthermore show that the $E$-theory category for locales that can be written as unions of finite open sublocales is equivalent to the category of $\mathrm{E}$-valued cosheaves.

2605.19552 2026-05-22 hep-th math.AG

Large Order Enumerative Geometry, Black Holes and Black Rings

大阶数枚举几何、黑洞和黑洞环

Sergei Alexandrov, Albrecht Klemm, Boris Pioline

AI总结 通过利用高亏格Gopakumar-Vafa不变量的新数据,研究了一类单参数超几何Calabi-Yau三重线的5D指数、稳定对(PT)不变量和一阶Donaldson-Thomas(DT)不变量在大电荷下的增长情况。发现5D指数在角动量临界值以下与旋转5D BMPV黑洞的Bekenstein-Hawking-Wald熵一致,包括四导数相互作用的次领修正;当角动量超过临界值时,5D指数由最小可能偶极子电荷的黑洞环主导。稳定对不变量在负角动量下表现出黑洞/环相变,但在正角动量下却出现两个其他相变:首先进入平台,然后进入多项式增长。DT不变量在负角动量下与PT不变量相似,随后过渡到由D0膜主导的相,其熵为m的2/3次方。此外,确定了固定亏格、大度数下的GV不变量行为,扩展了其到大亏格的有效公式,并指出PT/MSW关系的不合理有效性,验证了Mariño的猜想。

Comments 63 pages, 26 figures, 69 plots in total

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AI中文摘要

利用目前可用的高亏格Gopakumar-Vafa不变量数据,我们研究了一类单参数超几何Calabi-Yau三重线的5D指数、稳定对(PT)不变量和一阶Donaldson-Thomas(DT)不变量在大电荷下的增长情况。对于5D指数Ω_{5D}(d,m),在角动量m低于临界值时,发现其与旋转5D BMPV黑洞的Bekenstein-Hawking-Wald熵完美一致,包括来自四导数相互作用的次领修正。当m超过临界值时,5D指数由具有最小可能偶极子电荷的黑洞环主导。稳定对不变量PT(d,m)由5D指数确定,其在负m(现在解释为D0膜电荷)下表现出黑洞/环相变,但意外地在正m下出现两个其他相变:首先进入平台,然后进入多项式增长~m^{2d-1}。在每个相中,我们推导出不变量的近似表达式。最后,一阶DT不变量DT(d,m)在负m下与PT(d,m)相似,然后过渡到由D0膜主导的相,其熵为m^{2/3}的顺序。此外,我们确定了固定亏格、大度数下的GV不变量行为(包括整体g依赖的常数),将其扩展到适用于大g的近似公式,指出PT/MSW关系的不合理有效性,并研究了固定度数下的拓扑自由能增长,验证了Mariño的猜想。

英文摘要

Exploiting newly available data on Gopakumar-Vafa invariants at high genus for one-parameter hypergeometric Calabi-Yau threefolds, we study numerically the growth of the 5D indices, stable pair (PT) invariants and rank one Donaldson-Thomas (DT) invariants at large charges. For the 5D index $Ω_{5D}(d,m)$, below a critical value of the angular momentum $m$, we find perfect agreement with the Bekenstein-Hawking-Wald entropy of rotating 5D BMPV black holes, including the subleading correction from 4-derivative interactions. When $m$ exceeds the critical value, the 5D index is instead dominated by black rings with the smallest possible dipole charge. The stable pair invariant $PT(d,m)$, which is determined by 5D indices, has a similar black ring/hole transition at negative $m$ (now interpreted as the D0-brane charge) but surprisingly exhibits two other phase transitions at positive $m$: first, to a plateau and then to a polynomial growth $\sim m^{2d-1}$. In each phase, we derive an approximate expression for the invariant. Finally, the rank one DT invariant $DT(d,m)$ is similar to $PT(d,m)$ at negative $m$, and then transitions to a phase dominated by D0-branes, with entropy of order $m^{2/3}$. Along the way, we determine the fixed genus, large degree behavior of GV invariants (including the overall $g$-dependent constant), extend it to an approximate formula valid also for large $g$, point out the unreasonable effectiveness of a simple PT/MSW relation, and study the growth of topological free energies at fixed degree, confirming a conjecture of Mariño.

2605.19449 2026-05-22 math.CO cs.DM

On the number of finite additive 2-bases

关于有限加性2-基的数量

Stefan Weltge, Konrad Zyhalko

AI总结 本文通过简单的概率方法直接证明了有限加性2-基的数量呈指数增长,而非使用复分析技术。

Comments 4 pages; minor fix in the proof of Theorem 1.1

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AI中文摘要

已知有限加性2-基的数量呈指数增长。虽然这一事实由Marzuola和Miller(2010)通过嵌入数值集研究中的复分析技术所建立,但我们提供了一个直接且简短的证明,使用了基本的概率论方法。

英文摘要

The number of finite additive 2-bases is known to grow exponentially. While this fact has been established by Marzuola and Miller (2010) using complex analytic techniques embedded in the study of numerical sets, we provide a direct, short proof using elementary probabilistic arguments.