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2605.21888 2026-05-22 cond-mat.mes-hall

Spin torque driven mode hybridization and band engineering in nanopatterned magnonic crystals

由自旋扭矩驱动的模式杂化与带工程在纳米图案化磁子晶体中

Nikhil Kumar

AI总结 该研究通过在Permalloy/重金属双组分磁子晶体中展示可调的模式耦合和带杂化,利用平面波方法和线性化的Landau Lifshitz方程,展示了自旋电流诱导的自旋扭矩如何产生磁波频率的周期性调制,从而实现动态控制磁波色散,并通过观察局部化与传播Damon Eshbach模式之间的避避交点,实现了可调的杂化间隙、带变形和增强的模式混合。

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AI中文摘要

自旋波传播和动态控制对于可重构的磁子和自旋电子器件至关重要。在这里,展示了一种由纳米图案化双组分磁子晶体中的可调模式耦合和带杂化。该磁子晶体由Permalloy/重金属双层构成,其上分布着二维的Co纳米点阵。利用平面波方法和带有场类扭矩项的线性化Landau Lifshitz方程,我们表明不均匀的电流诱导自旋扭矩会产生磁波频率的周期性调制,从而实现磁波色散的动态控制。观察到局部化和传播Damon Eshbach模式之间显著的避避交点,导致可调的杂化间隙、带变形和增强的模式混合。自旋扭矩诱导的调制使模式转换和可重构的杂化磁子态得以实现,展示了纳米尺度自旋波动力学的高效电调制。

英文摘要

Spin wave propagation and dynamic control are essential for reconfigurable magnonic and spintronic devices. Here, tunable mode coupling and band hybridisation are demonstrated in a nanopatterned bicomponent magnonic crystal consisting of a Permalloy/heavy metal bilayer patterned with a two dimensional array of Co nanodots. Using the plane wave method and the linearised Landau Lifshitz equation with a field like torque term, we show that inhomogeneous current induced spin torque produces periodic modulation of the magnonic frequency, enabling dynamic control of spin-wave dispersion. A pronounced avoided crossing between localised and propagating Damon Eshbach modes is observed, leading to tunable hybridisation gaps, band deformation, and enhanced mode mixing. The spin torque induced modulation enables controlled mode conversion and reconfigurable hybrid magnonic states, demonstrating efficient electrical tuning of nanoscale spin-wave dynamics.

2605.21887 2026-05-22 gr-qc physics.ed-ph

Quantitative Black Hole Imaging Laboratory with the Black Hole Vision App: I. Schwarzschild Spacetime

具有黑洞愿景应用的量化黑洞成像实验室:I.Schwarzschild时空

Lior M. Burko

AI总结 本文利用Black Hole Vision智能手机应用,通过定量分析模拟的黑洞成像,推动广义相对论教育的转变。针对Schwarzschild时空,研究设计了适合本科生的分层模块化结构,并为广义相对论或相对论天体物理的研究生课程提供了扩展版本。通过将移动设备转化为教育相对论成像工具,利用独立探测器三角测定模拟Schwarzschild质量,通过雅可比映射表征各向异性坐标变换,通过整合坐标长度进行全局数值一致性检验,通过测量模拟Lyapunov指数量化近束缚轨道的指数不稳定性,最后通过模拟时空中的子像素约束来限制对称性。通过整合这一统计框架,本文使学生能够利用已建立的计量学协议探索物理特征与仪器噪声之间的区别。

Comments 12 pages, 2 figures

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AI中文摘要

本文利用{\it Black Hole Vision}智能手机应用,通过定量分析模拟的黑洞成像,推动广义相对论教育的转变。针对Schwarzschild时空,研究设计了适合本科生的分层模块化结构,并为广义相对论或相对论天体物理的研究生课程提供了扩展版本。通过将移动设备转化为教育相对论成像工具,我们利用独立探测器三角测定模拟Schwarzschild质量,通过雅可比映射表征各向异性坐标变换。通过整合坐标长度进行全局数值一致性检验,同时通过测量模拟Lyapunov指数量化近束缚轨道的指数不稳定性。最后,通过在模拟时空中的子像素约束来限制对称性。通过整合这一统计框架,本文使学生能够利用已建立的计量学协议探索物理特征与仪器噪声之间的区别。

英文摘要

This paper utilizes the {\it Black Hole Vision} smartphone application to catalyze a pedagogical shift in General Relativity education through the quantitative analysis of simulated black hole imaging. Presented here for the Schwarzschild spacetime, the investigation is designed with a hierarchical modularity suitable for undergraduate students, with an expanded version intended for graduate courses in General Relativity or Relativistic Astrophysics. By transforming the mobile device into an educational relativistic imaging tool, we triangulate the simulated Schwarzschild mass through independent probes and characterize anisotropic coordinate transformations via a Jacobian map. Global numerical consistency is investigated through integrated coordinate length, while the exponential instability of nearly bound orbits is quantified through a measurement of the simulated Lyapunov exponent. Finally, symmetry is constrained through a sub-pixel constraint on eccentricity in the simulated spacetime. By integrating this statistical framework, the paper enables students to explore the distinction between physical signatures and instrumental noise using established metrological protocols.

2605.21886 2026-05-22 astro-ph.SR

Photospheric abundances of the rapidly-rotating A-type star Altair

快速旋转A型星Altair的色球丰度

Yoichi Takeda

AI总结 本研究通过合成光谱拟合技术分析了快速旋转的A型星Altair的色球丰度,发现其整体金属度可能略低于太阳,但没有显著的化学异常。

Comments 15 pages, 6 figures and 5 tables (with ancillary data), accepted for publication in Astrophysics and Space Science

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AI中文摘要

Altair是一颗已知具有显著扁球形的A型星,因其极快的自转速度(约300 km/s)而闻名。尽管已有大量关于该星的研究,但其化学丰度却鲜有研究,这可能是因为快速自转导致光谱线显著变宽且彼此重叠。受此情况启发,本研究采用光谱分析技术,通过合成光谱拟合法研究Altair的色球丰度,以确定是否存在化学异常。确定微湍流速度为2.9±0.9 km/s,要求金属度不出现区域依赖性。然后推导出17种元素(C、N、O、Mg、Al、Si、S、Ca、Sc、Ti、Cr、Mn、Fe、Ni、Zn、Sr、Ba)的丰度,尽可能考虑非局部热平衡效应。结果表明存在显著的区域间分散(数个十次方或更多),反映了对如此快速旋转星体可靠丰度确定的困难。然而,所有元素相对于太阳的相对平均丰度均落在-0.5 < [X/H] < +0.3范围内,且不依赖于原子序数。因此,我们得出结论:(1)Altair大气层中没有显著的化学丰度异常;(2)但其整体金属度可能略低于太阳(平均约为-0.2 dex)

英文摘要

Altair is an A-type star known to have an appreciably oblate shape owing to its very fast rotation (~300 km/s). Despite of numerous publications on this star, its chemical abundances have been scarcely investigated so far, presumably because of the practical difficulty that spectral lines are considerably broadened by rapid rotation and badly blended with each other. Motivated by this situation, a spectroscopic analysis was conducted to study the photospheric abundances of Altair by using the synthetic spectrum-fitting technique, in order to clarify whether or not any chemical peculiarities exist. The microturbulent velocity was determined to be 2.9 (+/-0.9) km/s by requiring that the metallicity does not show any systematic region-dependence. Then, the abundances of 17 elements (C, N, O, Mg, Al, Si, S, Ca, Sc, Ti, Cr, Mn, Fe, Ni, Zn, Sr, Ba) were derived, where the non-LTE effect was taken into consideration as much as possible. The results revealed considerable region-by-region dispersion (several tenths dex or even more), reflecting the difficulty of reliable abundance determination for such a very rapid rotator. Nevertheless, the differential mean abundances relative to the Sun turned out to fall within -0.5 < [X/H] < +0.3 for all elements without any dependence upon the atomic number. Accordingly, we may conclude that (1) no appreciable anomalies of chemical abundance patterns exist in the atmosphere of Altair, (2) but its global metallicity is likely to be slightly subsolar (~-0.2 dex on the average).

2605.21885 2026-05-22 math.OC cs.NA math.NA

Proximal Gradient-based Low Rank Tensor Decomposition for State Dependent Riccati Equation

基于proximal梯度的低秩张量分解用于状态依赖的Riccati方程

Jiahua Jiang, Carmeliza Navasca

AI总结 本文提出了一种基于proximal梯度的低秩张量分解方法,用于解决由偏微分方程产生的大离散维控制系统最优控制问题,通过稀疏优化和灵活混合方法获得低秩CP张量基元素,从而将最优控制问题转化为可高效求解的状态依赖Riccati方程。

Comments 6 pages, 4 figures, 1 table

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AI中文摘要

我们针对由偏微分方程产生的具有大离散维控制系统的最优控制问题进行研究。为了获得降阶模型,我们从canonical polyadic (CP)分解中寻找基元素。张量数据集来自大型模型的快照。我们的降阶控制系统方法是通过稀疏优化和灵活混合方法来获得低秩CP张量基元素。降阶最优控制问题导致降阶的状态依赖Riccati方程,这些方程可以高效求解。

英文摘要

We address the optimal control problems arising from partial differential equations with large discrete dimensional control systems. To obtain reduced order models, we find basis elements from the canonical polyadic (CP) decomposition. Tensor datasets are from snapshots of the large models. Our method to reduce the control system is to use dimensionality reduction approaches through sparse optimization and flexible hybrid methods is to obtain low rank CP tensor basis elements. The reduced optimal control problem leads to reduced state-dependent Riccati Equations which can be solved efficiently.

2605.21884 2026-05-22 stat.ME

Trend and seasonality estimation for point-process time series

点过程时间序列的趋势和季节性估计

Daniel Gervini, Simon A. Kopischke

AI总结 本文提出了一种用于点过程时间序列趋势和季节性估计的简单M估计器,通过模拟研究其有限样本性能,并以芝加哥Divvy自行车共享系统中的自行车需求模式为例进行实数据应用。

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AI中文摘要

本文介绍了用于时间序列点过程的趋势和季节性估计器。我们假设点过程遵循具有对数高斯强度函数的时序或空间双随机泊松模型。所提出的估计器是计算简单的M估计器。其渐近分布被推导出来,通过模拟研究其有限样本性能。作为实际数据应用的例子,我们研究了芝加哥Divvy自行车共享系统中的自行车需求模式。

英文摘要

This article introduces estimators of trend and seasonality for time series of point processes. We assume the point processes follow a temporal or spatial doubly-stochastic Poisson model with log-Gaussian intensity functions. The proposed estimators are computationally simple M-estimators. Their asymptotic distribution is derived, and their finite-sample performance is studied by simulation. As an example of real-data application, we study the patterns of bike demand in the Divvy bike-sharing system of the city of Chicago.

2605.21881 2026-05-22 math.AP

When Do Riemann Solutions Consist of Rarefactions, Jumps, and Constants?

当Riemann解由稀疏波、跃变和常数组成时是什么情况?

Bradley J. Plohr, Stephen Schecter, Dan Marchesin

AI总结 本文研究了在仅假设解为可测且本质有界的条件下,Riemann解是否由稀疏波、跃变和常数组成,并引入了一种基于局部本质图像的单侧累积集来区分连续和不连续特征。

Comments 29 pages, 1 figure

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AI中文摘要

对于严格双曲守恒律组的Riemann问题的传统解预期由稀疏波、跃变和常数状态组成。本文研究了在仅假设解为可测且本质有界的条件下,Riemann解是否具有这种结构。为了区分$ L^\infty$解中的连续和不连续特征,我们引入了基于局部本质图像的单侧累积集。假设在有限区间内解在本质图像(ess-im)意义上是连续的,我们证明如果解是共振的(特征速度等于$x/t$),则它是一个稀疏波;否则,它是一个常数。尽管ess-im跃变可能不是跃变,但我们证明所有ess-im累积状态位于同一个Hugoniot曲线上,并具有相同的速度。如果存在ess-im跃变的极限点,则可能出现异常,但若ess-im跃变集是有限的,则$ L^\infty$ Riemann解具有有界变差,并由有限多个稀疏波、跃变和常数状态组成。

英文摘要

A solution of a Riemann problem for a strictly hyperbolic system of conservation laws is traditionally expected to consist of rarefaction waves, jump discontinuities, and constant states. In this paper, we investigate whether a Riemann solution has this structure when the solution is only assumed to be measurable and essentially bounded. To discriminate continuous and discontinuous features in an $L^\infty$ solution, we introduce one-sided accumulation sets based on local essential images. Supposing that throughout a bounded open interval a solution is continuous in the essential image (ess-im) sense, we prove that it is a rarefaction wave if it is resonant (the characteristic speed equals $x/t$), and otherwise it is constant. Although an ess-im discontinuity might not be a jump discontinuity, we show that all ess-im accumulation states lie on a common Hugoniot locus and have the same speed. Anomalies are possible if there are limit points of ess-im discontinuities, but if the set of ess-im discontinuities is finite, then an $L^\infty$ Riemann solution has bounded variation and is composed of finitely many rarefaction waves, jump discontinuities, and constant states.

2605.21880 2026-05-22 quant-ph

Device-Independent Quantum Secret Sharing Protocol Enhanced by Advantage Distillation

设备无关量子秘密分发协议通过优势蒸馏增强

Yong-Hui Yang, Jian-Hong Shi, Hong-Wei Li, Hai-Long Zhang, Yun-Teng Yang, Yu-Bing Zhu, Yan-Yang Zhou

AI总结 本文提出了一种通过优势蒸馏技术改进的设备无关量子秘密分发协议,提高了协议的噪声容忍度和安全性,扩展了最大安全通信距离。

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AI中文摘要

设备无关量子秘密分发(DI-QSS)通过消除对设备的信任来提供高安全性,但其实际性能受限于信道损耗和噪声。本工作将优势蒸馏技术从双用户量子密钥分发(QKD)扩展到三用户DI-QSS,重新设计了相应的数据交互和验证程序。该技术系统应用于基本协议和三种改进策略:噪声预处理、后选择及其组合。这种方法提高了噪声容忍度,降低了所需的全局检测效率阈值,并显著扩展了最大安全通信距离。数值模拟显示,对于光纤上的基本协议,最大安全距离从0.16公里增加到1.85公里,噪声容忍度从10.17%提高到28.49%。结果表明,将优势蒸馏技术扩展到三用户设置有效增强了协议的鲁棒性和实用性,提高了其对现实噪声的适应性,推动了更可靠的量子秘密分发系统的发展。

英文摘要

Device-independent quantum secret sharing (DI-QSS) provides high security by eliminating the need to trust devices, yet its practical performance is limited by channel loss and noise. This work extends advantage distillation from two-party quantum key distribution (QKD) to three-party DI-QSS, redesigning the corresponding data interaction and verification procedures. The technique is systematically applied to the basic protocol and three active improvement strategies: noise preprocessing, post-selection, and their combination. This approach enhances noise tolerance, reduces the required global detection efficiency threshold, and significantly extends the maximum secure communication distance. Numerical simulations demonstrate that for the basic protocol over fiber, the maximum secure distance increases from 0.16 km to 1.85 km, and the noise tolerance improves from 10.17% to 28.49%. The results show that generalizing advantage distillation to the three-party setting effectively strengthens the protocol's robustness and practicality, enhancing its adaptability to realistic noise and advancing the development of more reliable quantum secret sharing systems.

2605.21879 2026-05-22 astro-ph.GA

An AGN in the Antennae galaxies ?

猎犬星系中存在活动星系核吗?

Shinya Komugi, Toshiki Saito, Tomonari Michiyama, Yoshiyuki Inoue, Kouichiro Nakanishi, Kazuki Tokuda, Fumiya Maeda, Yuzuki Nagashima

AI总结 本文通过ALMA观测研究猎犬星系在100GHz波段的时间变异性,发现其中一源S4具有13天的特征时间尺度,表明其发射源小于0.01秒差距,可能为Compton厚的活动星系核。

Comments Accepted for publication in ApJ

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AI中文摘要

时间变异性是探测小尺度能量现象的强大工具,如活动星系核(AGN)。我们利用ALMA在100GHz波段2.5个月的观测数据,研究猎犬星系的时间变异性,这对典型的早期合并星系对而言,此前在光学、近红外和X射线波段没有AGN的迹象。猎犬星系中大多数100GHz探测结果在空间上扩展并与恒星形成区域相关,但南侧星系NGC 4039中的两个源是紧凑的。其中一个紧凑源S3在东北方向偏离NGC 4039的恒星峰值,10秒差距分辨率下勉强分辨。另一个源S4与NGC 4039的恒星峰值共位,即使在4秒差距的分辨率下仍然未分辨。我们通过这两个源的功率谱分析其时间变异性。我们发现S4具有13±3天的特征时间尺度,表明导致100GHz发射的现象小于0.01秒差距。通过将观测到的两个源的流量与各种候选起源进行比较,我们表明虽然S3可以被年轻的高质量恒星团或AGN解释,但S4更可能是一个可能为Compton厚的AGN。

英文摘要

Time variability is a strong probe of energetic phenomena which occur at small spatial scales, like Active Galactic Nuclei (AGN). We use ALMA observations at 100 GHz executed over a period of 2.5 months to look for time variability in the Antennae galaxies, a prototypical early stage merger galaxy pair, for which there are no previous signatures of an AGN in the optical, infrared or X-ray. Most 100 GHz detections in the Antennae are spatially extended and associated with star forming regions, but two sources in the southern galaxy NGC 4039 are compact. One of these compact sources, S3, is offset by 1 arcsecond in the northeast direction from the stellar peak of NGC 4039, and marginally resolved at 10 parsec resolution. The other source, S4, is co-spatial with the stellar peak of NGC 4039 and unresolved even at a resolution of 4 parsec. We examine the time variability of these two sources using their power spectrum. We find that S4 varies with a characteristic timescale of 13+/-3 days, indicating that the phenomena responsible for the 100 GHz emission is smaller than 0.01 parsecs. By comparing the observed flux of the two sources with various candidate origins, we show that while S3 can be explained either by a young massive stellar cluster or an AGN, S4 is likely to be an AGN that is possibly Compton-thick.

2605.21878 2026-05-22 eess.SP

Automated Detection of Urological Events in Bladder Pressure Signals with a Two-Stage Machine Learning Framework Validated on External Datasets

基于双阶段机器学习框架的膀胱压力信号中泌尿事件自动化检测:在外部数据集上的验证

Hassaan A. Bukhari, Vikram Abbaraju, Jay Patel, Becky Clarkson, Shachi Tyagi, Margot S. Damaser, Steve J. A. Majerus

AI总结 本文提出了一种双阶段机器学习框架,用于从单通道膀胱压力信号中自动检测泌尿事件,通过在外部数据集上验证其有效性,实现了对尿失禁、膀胱过度活动和排尿收缩等事件的准确分类。

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AI中文摘要

Objective: 传统尿动力学检查(UDS)提供了关键的诊断信息,但需要侵入性的双导管插入和手动标记临床重要事件。无线、无导管的膀胱功能测试正在成为家庭使用的工具,但仅提供膀胱压力(Pves)。我们开发了一个机器学习框架,该框架在UDS数据上进行训练和外部验证,用于从单通道(Pves)记录中自动分类泌尿事件。Methods: 我们分析了118个标注的UDS轨迹,将其分割为0.8秒的Pves间隔。使用离散小波变换,我们提取了每个片段的55个统计特征。连续片段(233,338个片段;三个类别)共享相同的类别,即腹腔(ABD)、膀胱过度活动(DO)或排尿收缩(VOID),被分组为事件,并应用中位数特征聚合以推导事件级表示。使用一个不平衡数据集,我们训练了一个双阶段多层感知机(MLP):阶段1区分VOID与非VOID,阶段2将非VOID分类为ABD和DO。模型在两个独立数据集上进行训练,并在第三个独立数据集上进行外部验证。此外,还进行了额外的跨数据集训练-验证排列,以评估其泛化能力。性能通过准确率、F1-宏、灵敏度、特异度和曲线下面积(AUC)进行评估。Results: 阶段1(VOID vs. 非VOID)实现了84%的准确率(平衡准确率76%),F1-宏0.74,AUC 0.85,而阶段2(ABD vs. DO)达到了90%的准确率(平衡准确率80%),F1-宏0.80,AUC 0.87。排列特征重要性表明大多数特征贡献显著。Conclusion: 我们的机器学习方法能够从Pves中准确自动检测泌尿事件,展示了单通道监测和未来家庭应用的可行性。

英文摘要

Objective: Conventional urodynamics (UDS) provide critical diagnostic information, but requires invasive dual catheterization and manual labeling of clinically important events. Wireless, catheter-free bladder function tests are becoming available for home use, but only provide vesical pressure (Pves). We developed a machine learning framework that was trained and externally validated on UDS data for automated urological event classification from single-channel (Pves) recordings. Methods: We analyzed 118 annotated UDS traces segmented into 0.8-second Pves intervals. Using the discrete wavelet transform, we extracted 55 statistical features per segment. Consecutive segments (233,338 segments; three classes) sharing the same class, abdominal (ABD), detrusor overactivity (DO), or voiding contraction (VOID), were grouped into events, and median feature aggregation was applied to derive event-level representations. Using an imbalanced dataset, we trained a two-stage multilayer perceptron (MLP): Stage 1 distinguished VOID vs non-VOID, and Stage 2 classified non-VOID into ABD and DO. The model was trained on two independent datasets and externally validated on a third independent dataset. Additional cross-dataset training-validation permutations were performed to assess generalizability. Performance was evaluated using accuracy, F1-macro, sensitivity, specificity, and area under the curve (AUC). Results: Stage 1 (VOID vs. non-VOID) achieved 84% accuracy (balanced accuracy 76%), F1-macro 0.74, and AUC 0.85, while Stage 2 (ABD vs. DO) reached 90% accuracy (balanced accuracy 80%), F1-macro 0.80, and AUC 0.87. Permutation feature importance indicated that most features contributed meaningfully. Conclusion: Our machine learning approach enables accurate automated detection of urological events from Pves, demonstrating feasibility for single-channel monitoring and future ambulatory applications.

2605.21877 2026-05-22 math.CO

A single $3$-graph with infinite stability number

一个具有无限稳定性数的单个3图

Heng Li, Xizhi Liu

AI总结 该研究构造了一个显式的3图,其稳定性数为无限,扩展了 Hou-Li-Liu-Mubayi-Zhang 等人关于有限禁止家族的无限稳定性现象,并进一步发展了 Balogh-Clemen-Luo 在单禁止设置中的3图方向,其中指数级数的精确极值构造共存于稳定性中。

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AI中文摘要

一个禁止家族的稳定性数衡量需要多少种不同的结构来近似所有避免它的近极值构造。无限稳定性数意味着没有有限的结构列表足够。我们构造了一个简单的显式3图,其稳定性数为无限。这扩展了 Hou-Li-Liu-Mubayi-Zhang 等人关于有限禁止家族的无限稳定性现象到单禁止设置,并进一步发展了 Balogh-Clemen-Luo 在单禁止设置中的3图方向,其中指数级数的精确极值构造共存于稳定性中。

英文摘要

The stability number of a forbidden family measures how many different structures are needed to approximate all near-extremal constructions avoiding it. An infinite stability number means that no finite list of structures suffices. We construct a simple explicit $3$-graph whose stability number is infinite. This extends the infinite-stability phenomenon for finite forbidden families, established by Hou--Li--Liu--Mubayi--Zhang, to the single-forbidden setting, and further develops the single-$3$-graph direction of Balogh--Clemen--Luo, in which exponentially many exact extremal constructions coexist with stability.

2605.21876 2026-05-22 math.NT

The reverse Goldbach problem and a refined Zsiflaw--Legeis theorem

反Goldbach问题与改进的Zsiflaw-Legeis定理

Michael Harm, Daniel R. Johnston

AI总结 本文研究反素数的加法理论,证明了大奇数可以表示为素数与两个反素数之和,以及大奇数可以表示为两个素数与一个反素数之和,并证明几乎所有的偶数可以表示为一个素数与一个反素数之和,同时所有大整数可以表示为一个反素数与一个平方自由数之和。

Comments 34 pages

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AI中文摘要

我们证明了关于反素数$\overleftarrow{p}$的加法理论的新结果;即,固定基$ b\geq 2 $下,将素数$p$反向写作得到的反素数。特别地,我们研究了Goldbach猜想的一个变种,探讨整数作为素数与反素数之和的表示。我们证明了:(1) 每个大的奇整数都可以表示为一个素数和两个反素数之和($N=p_1+\overleftarrow{p_2}+\overleftarrow{p_3}$);(2) 每个大的奇整数都可以表示为两个素数和一个反素数之和($N=p_1+p_2+\overleftarrow{p_3}$);(3) 几乎所有的偶整数都可以表示为一个素数和一个反素数之和($N=p_1+\overleftarrow{p_2}$);(4) 所有大的整数都可以表示为一个反素数和一个平方自由数之和($N=\overleftarrow{p}+η$,$μ^2(η)=1$)。为了获得这些结果以及相关的渐进行为,我们应用了Hardy-Littlewood圆方法以及一个改进的“Zsiflaw-Legeis”定理,该定理研究了反素数在算术级数中的分布。值得注意的是,我们的Zsiflaw-Legeis定理变体不需要固定数位长度,这不同于之前的版本。

英文摘要

We prove new results on the additive theory of reversed primes $\overleftarrow{p}$; that is, primes $p$ which are written backwards in a fixed base $b\geq 2$. In particular, we study a variant of Goldbach's conjecture, looking at representations of integers as the sum of primes and reversed primes. We show that: (1) Every large odd integer is the sum of a prime and two reversed primes ($N=p_1+\overleftarrow{p_2}+\overleftarrow{p_3}$). (2) Every large odd integer is the sum of two primes and a reversed prime ($N=p_1+p_2+\overleftarrow{p_3}$). (3) Almost all even integers are the sum of a prime and a reversed prime ($N=p_1+\overleftarrow{p_2}$). (4) All large integers are the sum of a reversed prime and a square-free number ($N=\overleftarrow{p}+η$, $μ^2(η)=1$). To obtain our results, along with associated asymptotics, we apply the Hardy--Littlewood circle method and a novel refinement of the ``Zsiflaw--Legeis" theorem on the distribution of reversed primes in arithmetic progressions. Notably, our variant of the Zsiflaw--Legeis theorem does not require one to fix the digit length unlike previous versions.

2605.21875 2026-05-22 physics.ao-ph

Water vapor buoyancy and the African easterly jet

水汽浮力与非洲东风急流

Heng Quan, Da Yang, William Boos, Tiffany Shaw, Huazhi Ge, Yaoxuan Zeng, Carly KleinStern

AI总结 本文研究了水汽浮力对非洲东风急流的影响,发现水汽梯度显著抵消了温度梯度对密度平衡的影响,导致急流强度减少30%,并指出全球变暖下这一效应增强,强调了水汽分布对大尺度环流的重要性。

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AI中文摘要

非洲东风急流(AEJ)是热带大气中显著的环流特征,它输送矿物尘埃并生成东风波,这些波是飓风的种子。传统观点认为AEJ处于热风平衡中,与北非的正经向温度梯度平衡。本文利用再分析数据表明,负经向水汽梯度显著抵消了温度梯度对密度平衡的影响,诊断性地解释了AEJ强度减少30%。利用CMIP6数据进一步表明,水汽浮力对AEJ的影响在全球变暖下增强,突显了水汽分布对大尺度环流的关键作用。对CMIP6模型中AEJ的分析证实,一些模型未将水汽浮力纳入其控制方程中,这引发了关于这些模型对该地区气候变化预测相关性的问题。

英文摘要

The African easterly jet (AEJ) is a prominent circulation feature in the tropical atmosphere. It transports mineral dust and generates easterly waves that serve as seeds for hurricanes. Conventional wisdom holds that the AEJ is in thermal wind balance with the positive meridional temperature gradient over North Africa. Here, using reanalysis data, we show that the negative meridional moisture gradient substantially counteracts the effect of the temperature gradient on density in that balance, diagnostically accounting for a 30\% reduction of the AEJ magnitude. Using CMIP6 data, we further show that this effect of vapor buoyancy on the AEJ strengthens under global warming, highlighting the critical role of the spatial distribution of moisture on large-scale circulation. Analysis of the AEJ in CMIP6 models confirms that some models do not include vapor buoyancy in their governing equations, raising questions about the relevance of their projections of climate change in that region.

2605.21873 2026-05-22 math.OA math.LO

Ultrapowers of spectral subspaces

谱子空间的超幂

Hiroshi Ando, Isaac Goldbring

AI总结 本文研究了在III_1因子W*概率空间中,谱子空间的超幂是否为另一个谱子空间的真子集,并探讨了该结果的模型论意义。

Comments 10 pages; first draft; comments welcome!

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AI中文摘要

我们证明,在任何W*概率空间(M,φ)中,其中M是III_1因子,对于任何非平凡的、真闭的F⊆R和任何N上的非主超滤子U,谱子空间M(σ^φ,F)的超幂M(σ^φ,F)^U是谱子空间M^U(σ^{φ^U},F)的真子集。我们讨论了这一结果的模型论意义。

英文摘要

We prove, for any W$^*$-probability space $(M,φ)$ where $M$ is a type $\mathrm{III}_1$ factor, any nontrivial, proper closed $F\subseteq \mathbb{R}$, and any nonprincipal ultrafilter $\mathcal{U}$ on $\mathbb{N}$, that the ultrapower $M(σ^φ,F)^{\mathcal{U}}$ of the spectral subspace $M(σ^φ,F)$ is a proper subset of the spectral subspace $M^{\mathcal{U}}(σ^{φ^{\mathcal{U}}},F)$. We discuss the model-theoretic implications of this result.

2605.21872 2026-05-22 physics.flu-dyn

On the wake region of high-Reynolds-number turbulent boundary layers subject to adverse pressure gradients

关于高雷诺数湍流边界层受逆压梯影响的涡旋区域

Mitchell Lozier, Ahmad Zarei, Ivan Marusic, Rahul Deshpande

AI总结 研究高雷诺数湍流边界层在中等逆压梯作用下涡旋区域的结构特征,通过多点测量分析湍流运动的能量分布和相干性,揭示逆压梯对涡旋区域能量变化的影响。

Comments 6 pages, 5 figures, accepted for 14th International Symposium on Turbulence and Shear Flow Phenomena (TSFP14)

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AI中文摘要

通过互补的多点测量,实验研究了中等逆压梯对高雷诺数湍流边界层(TBL)结构的影响。与许多先前研究不同,本研究聚焦于涡旋区域,旨在表征由局部逆压梯条件激发的湍流运动。同时使用两点热线测量流速来估计线性相干谱(LCS),量化涡旋区域参考点与TBL其余部分的壁法向相干性。基于LCS的频谱能量和方差分解显示,与涡旋区域参考点相干的运动占逆压梯引起的较大时间尺度能量增加的显著部分,但并非全部增强能量。剩余的增加与相对较小尺度的不相关运动有关。随后使用高空间分辨率快照PIV测量研究了这一更广泛的高能运动,这些运动与涡旋区域的 spanwise 环流有关。在0.2 < z/δ < 0.4范围内评估了spanwise环量统计,该范围观察到最大的逆压梯引起的频谱能量变化。在逆压梯作用下,该区域的spanwise环量的均值和方差显著增加,而旋涡强度分布证实了该区域spanwise环流数量和强度的相对增加。最后,使用不同的旋涡强度阈值识别了动态显著的顺时针旋转spanwise环流。较高的阈值产生了条件平均速度场,最佳捕捉了关键涡旋区域的动力学,推动其用于基于环流的条件平均分析。

英文摘要

The effect of a moderate adverse pressure gradient (APG) on the structure of a high-Reynolds-number turbulent boundary layer (TBL) was investigated experimentally using complementary multi-point measurements. Unlike many previous studies, the present work focuses on the wake region and aims to characterise the turbulent motions that are energised by local APG conditions. Simultaneous two-point hot-wire measurements of the streamwise velocity were used to estimate the linear coherence spectrum (LCS), quantifying the wall-normal coherence between a wake-region reference point and the rest of the TBL. LCS-based decomposition of the spectral energy and variance showed that motions coherent with the wake reference account for a significant part of the APG-induced increase at large time scales, but not all of the enhanced energy. The remaining increase is associated with relatively smaller-scale motions that are not correlated with the selected wake location. High-spatial-resolution snapshot PIV measurements were then used to examine this broader range of energetic motions, which are associated with spanwise vortices in the wake region. Spanwise vorticity statistics were evaluated over 0.2 < z/δ < 0.4, where the largest APG-induced change in spectral energy was observed. Under APG, both the mean and variance of spanwise vorticity increased significantly in this region, while swirling-strength distributions confirmed a relative increase in both the population and magnitude of spanwise vortices. Finally, dynamically significant clockwise rotating spanwise vortices were identified using different swirling-strength thresholds. Higher thresholds produced conditionally averaged velocity fields that best captured the key wake-region dynamics, motivating their use for vortex-based conditional averaging in future analyses.

2605.21870 2026-05-22 hep-ph

Deep Neural Networks for Heavy Lepton-Flavor-Violating Higgs Searches at the LHC

在LHC上利用深度神经网络进行重Higgs玻色子电轻子味违反衰变搜索

Akmal Ferdiyan, Reinard Primulando, Fiki Taufik Akbar, Bobby Eka Gunara

AI总结 本文研究了在III型双Higgs双态模型中重Higgs玻色子H→μτ的电轻子味违反衰变,并通过在13 TeV能量下使用35.9 fb⁻¹的数据重新分析CMS搜索,利用快速探测器模拟在200-450 GeV质量范围内进行。通过开发一个训练于最终态动能变量的深度神经网络分类器,结合质量依赖性的阈值优化,将信号截面的预期95%置信度上限减少了42-46%(0喷注通道)和36-40%(1喷注通道),相对于标准共线质量(M_col)基线。同时应用SHAP可解释性分析,识别出可见质量m_vis作为主要的区分特征,反映了τ衰变中中微子动量分数的特征。结果显示,补充M_col分析的简化质量依赖性预选,m_vis < f·m_H(f=0.7(0喷注)和f=0.8(1喷注)),在不需多变量基础设施的情况下,能够持续提高灵敏度。此外,一个训练以预测m_H/M_col比值的DNN回归模型纠正了共线近似中固有的系统预测偏差,保持信号至400 GeV时的绝对质量预测误差低于1 GeV,并在m_H=450 GeV时将质量分辨率提高12%(0喷注)和21%(1喷注)。这些结果展示了在LHC上显著增强电轻子味违反Higgs搜索灵敏度的明确路径。

Comments 22 pages, 11 figures

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AI中文摘要

我们研究了在III型双Higgs双态模型中重Higgs玻色子H→μτ的电轻子味违反衰变,在13 TeV能量下使用35.9 fb⁻¹的数据重新分析CMS搜索,利用快速探测器模拟在200-450 GeV质量范围内。我们开发了一个训练于最终态动能变量的深度神经网络(DNN)分类器,结合质量依赖性的阈值优化,将信号截面的预期95%置信度上限减少了42-46%在0喷注通道和36-40%在1喷注通道,相对于标准共线质量(M_col)基线。我们应用SHAP可解释性分析,识别出可见质量m_vis作为主要的区分特征,反映了τ衰变中中微子动量分数的特征。我们显示,补充M_col分析的简化质量依赖性预选,m_vis < f·m_H(f=0.7(0喷注)和f=0.8(1喷注)),在不需多变量基础设施的情况下,能够持续提高灵敏度。此外,一个训练以预测m_H/M_col比值的DNN回归模型纠正了共线近似中固有的系统预测偏差,保持信号至400 GeV时的绝对质量预测误差低于1 GeV,并在m_H=450 GeV时将质量分辨率提高12%(0喷注)和21%(1喷注)。这些结果展示了在LHC上显著增强电轻子味违反Higgs搜索灵敏度的明确路径。

英文摘要

We study lepton-flavor-violating (LFV) decays of a heavy Higgs boson, $H \to μτ$, in the Type-III two-Higgs-doublet model by recasting the CMS search at $\sqrt{s} = 13$ TeV with 35.9 fb$^{-1}$ using fast detector simulation in the mass range 200-450 GeV. We develop a deep neural network (DNN) classifier trained on final-state kinematic variables that, with mass-dependent threshold optimization, reduces the expected 95% CL upper limits on the signal cross section by 42-46% in the 0-jet channel and 36-40% in the 1-jet channel relative to the standard collinear mass ($M_\mathrm{col}$) baseline. We apply SHAP interpretability analysis to identify the visible mass $m_\mathrm{vis}$ as one of the dominant discriminating feature, reflecting the characteristic neutrino momentum fraction of the $τ$ decay. We show that supplementing the $M_\mathrm{col}$ analysis with a simplified mass-dependent pre-selection, $m_\mathrm{vis} < f \cdot m_H$ with $f = 0.7$ (0-jet) and $f = 0.8$ (1-jet), consistently improves the sensitivity over the $M_\mathrm{col}$-only baseline without requiring multivariate infrastructure. In addition, a DNN regression model trained to predict the ratio $m_H/M_\mathrm{col}$ corrects the systematic prediction bias inherent in the collinear approximation, maintaining an absolute mass prediction error below 1 GeV for signals up to 400 GeV and improving the mass resolution by 12% (0-jet) and 21% (1-jet) at $m_H = 450$ GeV. These results demonstrate a clear path toward significantly enhanced sensitivity in LFV Higgs searches at the LHC.

2605.21867 2026-05-22 quant-ph

Zero-level $CCZ$ Distillation

零级 $CCZ$ 状态提纯

Tomohiro Itogawa, Yutaka Hirano, Yutaro Akahoshi, Keisuke Fujii

AI总结 本文提出了一种零级提纯协议,利用二维正方形晶格中的近邻相互作用,仅用物理量子比特高效生成高保真度的逻辑 $CCZ$ 魔法状态,从而减少空间和时间开销,提升容错量子计算的可行性。

Comments 12 pages and 13 figures

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AI中文摘要

魔法状态提纯是容错量子计算的关键组成部分,因为它通过门传送实现了非克利夫顿门如 $T$ 门和 $CCZ$ 门的实现。然而,传统提纯协议需要大量逻辑量子比特并引入显著的空间和时间开销,成为可扩展容错量子计算的瓶颈。在本文中,我们提出了一种零级提纯协议,利用二维正方形晶格中的近邻相互作用,仅用物理量子比特高效生成高保真度的逻辑 $CCZ$ 魔法状态。我们的方法利用 $[[ 8,3,2 ]]$ 代码的横向 $T/T^\dagger$ 操作来容错地编码状态 $\overline{CCZ}|+++ angle$,随后通过晶格手术将其传送至三个表面码逻辑量子比特。为了使不同距离的代码之间能够进行传送,我们引入了自适应初始化传送(AIT),这是一种针对表面码的定制初始化程序。数值模拟显示,逻辑错误率与物理错误率 $p$ 的关系为 $p_L \simeq 300 imes p^2$。例如,与传统七 $T$ 门方法相比,在 $p = 10^{-3}$ 和 $p = 10^{-4}$ 时,该方法将逻辑错误率降低了约一个和两个数量级。提纯电路仅需要 22 个物理量子比特、3 个逻辑量子比特和电路深度为 24,将空间时间开销降低了约 5-10 倍。这一结果突显了 $CCZ$ 状态提纯在早期容错量子计算中的实用性,并为超越传统 $T$ 状态生成的资源高效物理级魔法状态提纯提供了新方向。

英文摘要

Magic state distillation is a key component of fault-tolerant quantum computation, as it enables the implementation of non-Clifford gates such as the $T$ gate and the $CCZ$ gate via gate teleportation. However, conventional distillation protocols require a large number of logical qubits and introduce substantial spatial and temporal overhead, posing a significant bottleneck for scalable fault-tolerant quantum computation. In this work, we propose a zero-level distillation protocol that efficiently generates a high-fidelity logical $CCZ$ magic state using only physical qubits on a two-dimensional square lattice with nearest-neighbor interactions. Our method leverages the transversal $T/T^\dagger$ operation of the $[[ 8,3,2 ]]$ code to fault-tolerantly encode the state $\overline{CCZ}|+++\rangle$, which is subsequently teleported to three surface-code logical qubits via lattice surgery. To enable teleportation between codes with different distances, we introduce adaptively initialized teleportation (AIT), a tailored initialization procedure for the surface code. Numerical simulations demonstrate that the logical error rate scales as $p_L \simeq 300 \times p^2$ with respect to the physical error rate $p$. For example, the proposed method improves the logical error rate by approximately one and two orders of magnitude at $p = 10^{-3}$ and $p = 10^{-4}$, respectively, compared to conventional seven-$T$-gate approaches. The distillation circuit requires only 22 physical qubits, 3 logical qubits, and a circuit depth of 24, reducing the space-time overhead by a factor of approximately 5-10 compared to previous methods. This result highlights the practicality of $CCZ$-state distillation in early fault-tolerant quantum computation and offers a new direction toward resource-efficient physical-level magic state distillation beyond conventional $T$-state generation.

2605.21866 2026-05-22 math.CO cs.DM math.NT

Graphs from quadratic forms and vector spaces over finite fields

由二次型和有限域上的向量空间产生的图

Jean Godard, Lucas Reis

AI总结 本文研究了由二次型和有限域上的向量空间生成的图的性质,确定了哪些二次型使得图在任何子空间下都是无向的,并分析了这些图的连通性和 clique 数。

Comments 12 pages; comments are welcome!

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AI中文摘要

设 q 为奇素数幂,n≥2,且 V 是 F_q^n 的真子空间。给定一个非零二次型 Q(X,Y)∈F_q^n[X,Y],我们考虑由条件 Q(X,Y)∈V 自然产生的图 Γ(Q,V)。我们确定了所有二次型 Q,使得对于每个 V,Γ(Q,V) 无向。除了之前由第二作者研究的 Q(x,y)=XY 情况外,这基本上导致了形式 X²±Y² 和族 Q_b(X,Y):=X²+bXY+Y², b≠0。然后我们研究了相应图的连通性和 clique 数。我们的结果揭示了这些情况之间的明显对比。图 Γ(X²±Y²,V) 结构良好,不连通,其 clique 数可以达到 #V。另一方面,族 Q_b 看起来会产生不那么结构化的图:当 #V≥q^{3n/4} 时,图是连通的(实际上直径为 2),并且在许多情况下,其 clique 数是 o(#V)。我们的证明主要基于特征和,同时需要一些代数和组合思想。本文最后以一些开放问题和评论结束,包括对 q 为偶数情况的简要讨论。

英文摘要

Let $q$ be an odd prime power, let $n\ge 2$, and let $V\subsetneq \mathbb F_{q^n}$ be a proper $\mathbb F_q$-vector subspace. Given a nonzero quadratic form $Q(X,Y)\in \mathbb F_{q^n}[X,Y]$, we consider the graph $Γ(Q,V)$ that naturally arises from the condition $Q(X,Y)\in V$. We determine all quadratic forms $Q$ for which $Γ(Q,V)$ is undirected for every $V$. Besides the case $Q(x,y)=XY$, studied earlier by the second author, this essentially leads to the forms $X^2\pm Y^2$ and the family $Q_b(X, Y):=X^2+bXY+Y^2, b\ne 0$. We then study connectedness and clique number for the corresponding graphs. Our results reveal a clear contrast between these cases. The graphs $Γ(X^2\pm Y^2, V)$ are well structured, disconnected and their clique number can be as large as $\# V$. On the other hand, the family $Q_b$ seems to yield less structured graphs: the graphs are connected (in fact, of diameter $2$) if $\# V\ge q^{3n/4}$ and, in many cases, their clique number is $o(\# V)$. Our proofs are mainly based on character sums, while requiring a few algebraic and combinatorial ideas. We end the paper with some open problems and remarks, including a short discussion of the complementary case where $q$ is even.

2605.21865 2026-05-22 cs.CR cs.MM eess.IV

PEMark: Watermarking API Responses Based on Proxy Gateways and Position Encoding

PEMark: 基于代理网关和位置编码的API响应水印技术

Yifei Zhou, Xianjun Gu, Xinyu Dai, Ming Liu, Lansheng Han

AI总结 本文提出了一种基于代理网关和位置编码的API响应水印方法,通过重新排列JSON/XML键值对的顺序来实现无损水印嵌入,无需修改数据值,从而保持业务操作的连续性,同时确保API数据的可追溯性。

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AI中文摘要

API响应数据泄露问题已引起广泛关注。由于API通常未被充分监管,因此容易被滥用。一种常见解决方案是在API响应中嵌入水印以实现可追溯性。然而,现有水印方法通常需要修改数据库内容或API响应数据,这会迫使更改业务系统代码,甚至可能干扰正常业务操作,因为数据值被更改。在本文中,我们提出了一种原始的可插拔水印方案,基于水印代理网关和PEMark(基于位置编码的水印)。我们方法的关键创新点是利用JSON/XML键值对顺序中的内在排列冗余性——一个被忽视的维度,虽然不携带语义信息,但提供了丰富的编码能力。首先,我们将服务器响应转发到水印代理网关,这种设计不需要对现有业务系统进行任何修改。然后,我们通过位置编码在每个API响应中嵌入水印,重新排列键而不会改变任何数据值。据我们所知,这是首次通过代理网关使用位置编码实现无损API响应水印的技术。我们的方法不修改任何数据值,因此在水印嵌入后,正常业务操作可以无缝继续。实验结果表明,我们的框架在保持业务可用性的同时,确保了返回的API数据可追溯。与当前主流方案相比,我们的方法对篡改和插入攻击具有鲁棒性(100%相似性),并且能够抵御一定程度的删除攻击。

英文摘要

Data leakage from API responses has drawn wide attention. APIs are often not fully regulated, making them easy to abuse. One common solution is to embed watermarks into API responses for traceability. However, existing watermarking methods often require modifying database content or API response data. This forces changes to business system code, and may even disrupt normal business operations because data values are altered. In this paper, we propose an original pluggable watermarking scheme based on a watermark proxy gateway and PEMark (Position Encoding-based Watermarking). The key novelty of our approach is exploiting the inherent permutation redundancy in the ordering of JSON/XML key-value pairs -- an overlooked dimension that carries no semantic information yet provides abundant encoding capacity. First, we forward server responses to the watermark proxy gateway, a design that requires zero modification to existing business systems. Then, we embed a watermark into each API response using position encoding, which reorders keys without altering any data values. To the best of our knowledge, this is the first work to achieve distortion-free API response watermarking via position encoding over a proxy gateway. Our method does not modify any data values, so normal business operations continue seamlessly after watermark embedding. Experimental results show that our framework maintains business usability while ensuring that returned API data is traceable. Compared with current mainstream schemes, our method is robust against tampering and insertion attacks (100\% similarity), and can withstand certain levels of deletion attacks.

2605.21864 2026-05-22 physics.ao-ph

A Simulation Methodology Testbed for Typhoon Sensitivity Analysis: Framework Development and Perturbation-Response Experiments with the Pangu Weather Model

一种用于台风敏感性分析的模拟方法测试平台:框架开发与Pangu天气模型的扰动-响应实验

Yuehua Peng, Yuchen Zhang, Qin Huang, Chengzhi Ye, Jingsong Yang

AI总结 本文提出了一种基于Pangu天气模型和PID闭环技术的台风敏感性分析测试平台,通过单输入单输出系统进行可控扰动-响应实验,揭示了扰动范围、PID参数调节行为和不同扰动模式下的能量尺度响应特性,为后续多输入多输出架构和非线性PID或模型预测控制等高级分析策略提供了基础。

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AI中文摘要

理解台风对环境场局部扰动的响应对于评估预测极限和探索路径或强度干预的潜力至关重要。本研究通过整合高精度AI预报系统Pangu天气模型与比例-积分-微分(PID)闭环技术,开发了一个专用的模拟方法测试平台用于台风敏感性分析。该测试平台由模块化功能块组成,包括气象预测模块、人工扰动输入接口、台风定量建模模块和PID闭环测试模块,通过跨平台的MATLAB/ONNX技术框架实现。构建了单输入单输出(SISO)测试系统,将速度和热扰动设为核心输入,台风路径和强度作为关键输出目标,以进行受控扰动-响应实验。实验揭示了可行的扰动-响应范围、PID模块的参数调节行为以及不同扰动模式下的能量尺度响应特征,并量化了测试系统的输入-输出耦合关系。通过在操作AI天气预报模型上构建该测试平台,本研究提供了一个超越通常仅在低阶动力学模型上验证的理想化敏感性研究的框架。该测试平台为研究台风对人工环境扰动的敏感性提供了可扩展的平台,并为后续向多输入多输出架构和高级分析策略如非线性PID或模型预测控制等扩展奠定了基础。

英文摘要

Understanding how typhoons respond to localized perturbations in their environmental fields is fundamental to assessing the limits of predictability and exploring the potential for track or intensity intervention. This study develops a dedicated simulation methodology testbed for typhoon sensitivity analysis by integrating the Pangu weather model, a high-precision AI forecasting system, with Proportional-Integral-Derivative (PID) closed-loop techniques. The testbed is constructed with modular functional blocks including a meteorological prediction module, an artificial perturbation input interface, a typhoon quantitative modeling module, and a PID closed-loop test module, implemented via a cross-platform MATLAB/ONNX technical framework. A Single-Input Single-Output (SISO) test system was built, with velocity and thermal perturbations set as the core inputs and typhoon track and intensity as the key output targets, to perform controlled perturbation-response experiments. The experiments reveal the feasible perturbation-response range, the parameter tuning behavior of the PID module, and the energy-scale response characteristics under different perturbation modes, and quantify the input-output coupling relationships of the test system. By constructing this testbed on an operational AI weather forecasting model, this study provides a framework that goes beyond idealized sensitivity studies typically validated only on low-order dynamical models. The testbed offers an expandable platform for investigating typhoon sensitivity to artificial environmental perturbations and provides a foundation for subsequent expansion toward multi-input multi-output architectures and advanced analysis strategies such as nonlinear PID or model predictive control.

2605.21860 2026-05-22 math.ST cs.DS cs.IT math.IT stat.ML stat.TH

Robust Statistical Estimators with Bounded Empirical Sensitivity

具有有界经验敏感度的稳健统计估计量

Valentio Iverson, Gautam Kamath, Argyris Mouzakis, Adam Smith

AI总结 本文提出了一种衡量统计估计量鲁棒性的新指标,即经验敏感度。研究了高斯均值估计等典型问题中该量的界限,并证明了对于达到最优ℓ₂误差的估计量,经验敏感度下界为Ω(η+√(ηd/n)),并通过最近的鲁棒经验均值估计结果证明该下界在对数因子范围内是紧的。

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AI中文摘要

我们引入了一个新的鲁棒性度量标准,称为经验敏感度。一个估计量$\hat θ$具有有界经验敏感度,如果对于数据集$X = (X_1, \dots, X_n) \sim \mathcal{D}^{\otimes n}$,在高概率下,任何通过修改至多$ηn$个点得到的数据集$Y$,都有$\hat θ(Y)$接近$\hat θ(X)$。我们研究了该量在高斯均值估计等典型问题中的界限。我们证明了新的下界,显示对于任何达到最优ℓ₂误差下界$O\left(\sqrt{d/n} ight)$的估计量$\hat μ$,经验敏感度至少为$Ω\left(η+ \sqrt{ηd/n} ight)$。这两个项源于此类估计量的均值和方差的障碍(通过Efron-Stein论证)。我们通过最近的鲁棒经验均值估计结果证明该下界在对数因子范围内是紧的。

英文摘要

We introduce a new measure of robustness for statistical estimators, which we call \emph{empirical sensitivity}. An estimator $\hat θ$ has bounded empirical sensitivity if, with high probability over a dataset $X = (X_1, \dots, X_n) \sim \mathcal{D}^{\otimes n}$, for any dataset $Y$ obtained by modifying at most $ηn$ points in $X$, we have that $\hat θ(Y)$ is close to $\hat θ(X)$. We study bounds on this quantity for the prototypical problem of Gaussian mean estimation. We prove new lower bounds, showing that for any estimator $\hat μ$ which achieves an optimal $\ell_2$-error bound of $O\left(\sqrt{d/n}\right)$, the empirical sensitivity is at least $Ω\left(η+ \sqrt{ηd/n}\right)$. The two terms arise due to obstructions on the mean and variance (via an Efron-Stein argument) of such an estimator. We show that this bound is tight up to logarithmic factors, by employing recent results for robust empirical mean estimation.

2605.21857 2026-05-22 cs.CR

SPIDER: Two Server Functionality for the Cost of Zero

SPIDER: 仅需零成本的双服务器功能

Ofir Dvir, Kali Hale, Javin Zipkin, Divyakant Agrawal, Dahlia Malkhi

AI总结 本文提出了一种新的私有信息检索(PIR)方案SPIDER,该方案在保持现有最佳方案通信复杂度的同时,提高了常数因子的效率,并且在设计上更为简洁。SPIDER无需服务器合作即可运行,实现了无需专用API、辅助服务器状态或协议特定交互的隐私保护。

Comments 10 pages, 3 figures, submitted to ACM CCS 2026

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AI中文摘要

我们介绍了一种名为baseSPIDER和SPIDER的私有信息检索(PIR)方案,这些方案体现了两项技术进步。baseSPIDER协议使用单个服务器和一个具有状态的客户端,该客户端进行预处理并存储提示以供未来查询使用。在此设置中,baseSPIDER引入了一种新的方法,其通信复杂度与现有最佳方案的渐近最优性相匹配,同时提高了常数因子——对于具有大量条目的数据库来说,这一优势尤为显著。此外,baseSPIDER相较于先前的协议在设计上更为简洁。SPIDER在默认数据库接口上运行,不需要服务器在任何阶段的配合。据我们所知,SPIDER是首个采用这种设计的单服务器PIR构造,实现了隐私保护,而无需专用API、辅助服务器状态或协议特定交互,仅限于常规索引访问。SPIDER是通过将baseSPIDER简单地转换到默认服务器设置中构建的,消除了部署障碍,使能够立即应用于现有系统。这种转换可以更广泛地应用于三种最近的PIR解决方案,将它们适应到默认服务器范式中,并产生具有独立兴趣的解决方案。SPIDER与所得到的修改解决方案相比,展现出更简单的设计,但带来了更高的客户端计算工作量。

英文摘要

We introduce baseSPIDER and SPIDER, private information retrieval (PIR) schemes that embody two technical advancements. The baseSPIDER protocol operates with a single server and a stateful client that performs pre-processing and stores hints for future queries. In this setting, baseSPIDER introduces a new approach that matches the asymptotically optimal communication complexity of state-of-the-art schemes while improving constant factors--an advantage that is particularly significant for databases with large entries. In addition, baseSPIDER offers a conceptually simpler design relative to prior protocols. SPIDER operates over a default database interface and requires no cooperation from the server at any stage. To our knowledge, SPIDER is the first single-server PIR construction of this design, achieving privacy without specialized APIs, auxiliary server state, or protocol-specific interaction beyond conventional indexed access. SPIDER is built via a simple transformation of baseSPIDER to the default server setting, eliminating deployment barriers and enabling immediate applicability to existing systems. This transformation can be applied more broadly to three recent PIR solutions, adapting them for use in the default-server paradigm and yielding solutions of independent interest. SPIDER compares to the resulting modified solutions by exhibiting a simpler design while incurring higher client computational work.

2605.21855 2026-05-22 cond-mat.soft

Defect Kinematics in 2D Nematics: Contributions from Surface Topology, Intrinsic and Extrinsic Geometry, Solitons, Defect Orientations, and Elastic Anisotropy

二维向列相中缺陷动力学:来自表面拓扑、内在几何、孤子、缺陷取向和弹性各向异性的贡献

Joseph Pollard, Richard G. Morris

AI总结 本文通过几何场论研究了向列介质中载电拓扑缺陷的粒子状动力学,揭示了表面拓扑、内在几何、拓扑孤子、缺陷取向和弹性各向异性对缺陷动力学的影响。

Comments 27 pages, 6 figures

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AI中文摘要

我们通过几何场论研究了向列介质中载电拓扑缺陷的粒子状动力学。这与通常相比较的电磁理论不同,因为其缺乏规范不变性。在两种方法中,基本缺陷相互作用由一个传播子控制,其取决于表面的全局拓扑和/或内在几何。然而,在向列材料中,自由能的最小化对那些在规范不变理论中本应无关的约束敏感。通过霍奇理论将这些作为‘谐振’激发来捕捉,统一了已知影响向列相中缺陷动力学的两个因素:相对缺陷取向和拓扑孤子。此外,由于规范非不变性,向列材料也允许能量形式的扰动。那些在相应的欧拉-拉格朗日方程中引入非线性的扰动,导致缺陷相互作用超越成对相互作用,尽管底层U(1)对称性本质上是阿贝尔的。我们展示了这种诱导的多体效应在非零外在曲率和/或弹性各向异性情况下的表现。

英文摘要

We characterise the particlelike kinematics of charge-carrying topological defects in nematic media via a geometric field theory. This differs from the theory of electromagnetism, with which it is often compared, due to the absence of gauge-invariance. In both approaches, basic defect interactions are governed by a propagator, which depends upon the global topology and/or intrinsic geometry of the surface. For nematic materials, however, the minimisation of the free energy is sensitive to constraints that a gauge invariant theory would otherwise be indifferent to. Hodge theory is used to capture these as `harmonic' excitations, unifying two factors known to additionally affect the kinematics of defects in nematics: relative defect orientations and topological solitons. Perturbations to the form of the energy are also permitted in nematic materials due to gauge \emph{non}invariance. Those that introduce non-linearities in the corresponding Euler--Lagrange equations are shown to result in defect interactions that go beyond pairwise despite the otherwise abelian nature of the underlying U(1) symmetry. We show how this type of induced many-body effect manifests in the cases of non-zero extrinsic curvature and/or elastic anisotropy.

2605.21853 2026-05-22 cs.IT math.IT

An Information-theoretic Analysis of Edge-reinforced Random Walks

边缘增强随机游走的信息论分析

Qinghua, Ding, Venkat Anantharam

AI总结 本文研究了有限图上边缘增强随机游走的信息论特性,包括熵率、KL散度及其收敛性,以解决随机游走轨迹的统计区分问题。

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AI中文摘要

增强随机游走是在图上进行的随机游走,其边的转移概率与边的权重成正比,但边的权重会根据过去的遍历次数而变化。在边缘增强随机游走(ERRW)中,每当一条边被遍历(无论是哪个方向)时,其权重会增加1。在有限图上,ERRW可以表示为在随机环境中进行的随机游走。环境的分布由所谓的"魔公式"给出,该分布依赖于初始边权重。这种表示方法为研究ERRW的统计性质提供了自然途径。本文重点研究了有限图上ERRW的各种信息论量,受从观测轨迹中统计区分不同ERRW模型问题的启发。特别是,我们研究了ERRW的熵率。我们还研究了两个ERRW环境分布之间的KL散度,以及相应的有限轨迹分布之间的KL散度。利用底层随机环境的结构特性,我们推导了熵率的退化表示,得到了环境级KL散度的闭式公式,并对轨迹级KL散度向环境级KL散度收敛的收敛性进行了定量界分析。这些信息论量受ERRW轨迹的两点假设检验问题的启发,特别是与相关的Stein指数有关。我们还预计它们将在其他ERRW的检验问题研究中发挥根本性作用,包括身份检验和接近性检验。

英文摘要

Reinforced random walks are random walks on graphs whose transition probabilities along edges from a vertex are proportional to the weights of those edges, but where the weight of an edge evolves in a way that depends on the past traversals across it. In an edge-reinforced random walk (ERRW), the weight of an edge increases by $1$ whenever that edge is traversed, in either direction. On a finite graph, an ERRW admits a remarkable representation as a random walk in a random environment. The law of the environment is given by the so-called {\em magic formula}, with this law depending on the initial edge weights. This representation provides a natural route for studying statistical properties of ERRWs. This work focuses on various information-theoretic quantities associated with ERRWs on finite graphs, motivated in part by the problem of statistically distinguishing between different ERRW models from observed trajectories. In particular, we study the entropy rate of an ERRW. We also study the Kullback--Leibler divergence (KL divergence) between two ERRW environment laws, and the KL divergence between the corresponding finite-trajectory distributions. Leveraging structural properties of the underlying random environment, we derive an annealed representation of the entropy rate, a closed-form formula for the environment-level KL divergence, and quantitative bounds on the convergence of trajectory-level KL divergence toward environment-level KL divergence. These information-theoretic quantities are motivated by the two-point hypothesis testing problem for ERRW trajectories, and in particular by the associated Stein exponent. We also expect them to play a fundamental role in the study of other testing problems for ERRWs, including identity testing and closeness testing.

2605.21848 2026-05-22 stat.ME

Block-Independent Likelihood Ratio Testing for High-Dimensional Mean Vectors with Applications to Matrix-Variate Data

基于块独立的似然比检验用于高维均值向量的检验及其在矩阵变量数据中的应用

Minsub Shin, Kwangok Seo, Sang Han Lee, Johan Lim

AI总结 本文提出了一种新的检验方法BILT,用于检验两个高维均值向量的相等性,解决了传统方法在高维情况下失效的问题,并在矩阵变量数据中进行了应用验证。

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AI中文摘要

检验两个高维均值向量的相等性是多元分析中的基本问题。尽管经典的Hotelling's T²检验在低维情况下是最优的,但当维度p与样本量n相当或超过时,其表现不佳。已提出了一些扩展方法,包括对角似然比检验(DLRT),但这些方法在变量间存在相关性时会显著损失检验效能。本文提出了一种新的检验方法,即块独立似然比检验(BILT),通过放松变量间独立性假设为块独立性假设来推广DLRT。我们建立了BILT统计量在'增加p与小n'情况下渐近正态性的理论结果。进一步分析了BILT在局部替代假设下的渐近检验效能。大量模拟研究显示,BILT在广泛协方差结构下保持了类型I错误控制,并显著优于DLRT。对阿尔茨海默病神经影像计划(ADNI)数据集的应用进一步展示了BILT在检验两个矩阵变量总体均值差异中的应用。

英文摘要

Testing the equality of two high-dimensional mean vectors is a fundamental problem in multivariate analysis. While the classical Hotelling's $T^2$ test is optimal in low-dimensional settings, it fails when the dimension $p$ is comparable to or exceeds the sample size $n$. Several extensions, including the Diagonal Likelihood Ratio Test (DLRT), have been proposed under the working independence assumption among variables. However, such an assumption can lead to a substantial loss of power when correlations are present. In this paper, we propose a new test, the Block Independent Likelihood Ratio Test (BILT), which generalizes DLRT by relaxing the working independence assumption to a block independence assumption. We establish its asymptotic normality of the null distribution of the BILT statistic for 'increasing $p$ with small $n$' under mild regularity conditions. We further analyze the asymptotic power of BILT under a local alternatives. Extensive simulation studies show that BILT maintains Type I error control and achieves substantially higher power than DLRT across a wide range of covariance structures. An application to the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset further demonstrates the application of BILT to testing mean differences between two matrix-variate populations.

2605.21847 2026-05-22 cs.AR cs.DC

CompPow: A Case for Component-level GPU Power Management

CompPow: 对GPU组件级电源管理的论证

Shaizeen Aga, Mohamed Assem Ibrahim

AI总结 本文针对现代GPU内部的电源消耗问题,提出CompPow组件级电源管理方法,通过改进电源管理提升能效和性能。

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AI中文摘要

随着机器学习驱动的智能在各个领域的需求不断增长,GPU的普及已成为常态。同时,GPU以高能耗著称,并常主导典型机器学习数据中心的电力分配。尽管数据中心级的电源优化方法在收集GPU方面具有前景,但本文采取了不同的方法——即更深入地研究GPU内部的能耗。具体而言,由于现代GPU由集成组件组成,本文提出一种称为CompPow的组件感知方法,以改进现代GPU的电源管理。我们展示了对于各种机器学习操作和执行模式,CompPow有潜力提供更高的能效(10%)甚至改进的性能(5%)。最后,我们提出了关于如何通过组件感知的软硬件协同设计从现代GPU中提取额外的能效的建议。

英文摘要

The ever increasing demand for ML-driven intelligence in a wide spectrum of domains has led to ubiquity of GPUs. At the same time, GPUs are notorious for their power consumption needs and often dominate power allocation in a typical ML datacenter. While datacenter-level power optimizations which focus on collection of GPUs are promising, in this work, we take a different tack -- namely, we take a closer look at power consumption inside a GPU. Specifically, as modern GPUs are comprised of integrated components, we make a case for component-awareness, termed CompPow in this work, for improved power management in modern GPUs. We demonstrate for a variety of ML operations and execution patterns, CompPow has the potential to deliver higher energy efficiency (10%) and even improved performance (5%). We conclude with recommendations on how component-aware software-hardware co-design can extract additional energy efficiency from modern GPUs.

2605.21844 2026-05-22 nlin.AO cond-mat.stat-mech physics.soc-ph

A Utility-Driven Bounded-Confidence Model for Opinion Dynamics

基于效用的有界信心意见动力学模型

Alex Siebenmorgen, Juan G. Restrepo

AI总结 本文提出一种基于效用的有界信心模型,研究意见动态中的社会影响,通过效用景观和学习率确定有效势能,并展示多模态效用函数下的意见状态切换和集群合并。

Comments 5 pages with 4 figures plus Supplementary Material

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AI中文摘要

我们介绍了一种基于效用的有界信心意见动力学模型,在此模型中,与更高效用相关联的意见施加更强的社会影响。在所有代理属于单一意见簇的 regime 中,我们推导出平均意见的随机微分方程,并证明其稳态分布类似于吉布斯分布,其中有效势能由效用景观决定,逆温度由学习率和代理数量控制。对于多模态效用函数,动态表现出 metastability 和自发切换竞争意见状态。简化的随机描述也捕捉了多个意见簇的演变和合并,与基于代理的模拟结果一致。

英文摘要

We introduce a utility-driven bounded-confidence model of opinion dynamics in which opinions associated with higher utility exert stronger social influence. In the regime where all agents belong to a single opinion cluster, we derive a stochastic differential equation for the mean opinion and show that its stationary distribution is Gibbs-like, with an effective potential determined by the utility landscape and an inverse temperature controlled by the learning rate and the number of agents. For multimodal utility functions, the dynamics exhibit metastability and spontaneous switching between competing opinion states. The reduced stochastic description also captures the evolution and merging of multiple opinion clusters, in agreement with agent-based simulations.

2605.21841 2026-05-22 cond-mat.str-el cond-mat.mtrl-sci

Effect of Pb Substitution at the Mo site on the Magnetic Properties of the Polar Magnet Fe$_2$Mo$_3$O$_8$

Mo位Pb取代对极性磁体Fe$_2$Mo$_3$O$_8$磁性性质的影响

Takumi Shirasaki, Taichi Ishikawa, Shungo Nakayama, Hideki Kuwahara

AI总结 研究通过在Mo位引入非磁性Pb和Zr离子,破坏Mo的自旋单重态,从而在Mo层中产生活性自旋,展现出类似铁磁性的行为,即使在室温下也保持稳定,表明通过化学取代控制非磁性簇态是设计室温磁电材料的有效方法。

Comments 5 pages, 5 figures, accepted by IEEE Transactions on Magnetics

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AI中文摘要

三元过渡金属氧化物Fe$_2$Mo$_3$O$_8$是一种极性磁体,其特征是具有层状结构的磁性Fe蜂窝晶格和非磁性Mo科克洛夫特晶格。尽管先前研究主要集中在Fe位的化学取代以调节磁性性质,但Mo位由于Mo$^{4+}$离子的强自旋单重三元结构而被忽视。在本研究中,我们研究了将非磁性Pb$^{4+}$和Zr$^{4+}$离子取代到Mo位以有意破坏Mo三元结构的影响。我们的结果表明,破坏Mo自旋单重态会在Mo层中产生活性自旋,导致出现类似铁磁性的行为,即使在室温下也保持稳定。定量分析考虑到主要相的重量分数,表明在破坏三元结构后,每个活性Mo离子的有效自旋状态为S = 1/2。这些发现表明,通过化学取代控制极性宿主中的非磁性簇态是设计室温磁电材料的一种有前景的方法。

英文摘要

The ternary transition-metal oxide Fe$_2$Mo$_3$O$_8$ is a polar magnet characterized by a layered structure of magnetic Fe honeycomb lattices and non-magnetic Mo kagome lattices. Whereas previous studies have primarily focused on the chemical substitution at the Fe sites to modulate the magnetic properties, the Mo sites have remained largely unexplored due to the strong spin-singlet trimerization of Mo$^{4+}$ ions. In this study, we investigated the effect of substituting non-magnetic Pb$^{4+}$ and Zr$^{4+}$ ions into the Mo sites to intentionally disrupt the Mo trimers. Our results reveal that the disruption of the Mo spin-singlet state induces active spins within the Mo layer, resulting in the emergence of a ferromagnetic-like behavior that persists even at room temperature. Quantitative analysis that takes into account the weight fraction of the main phase suggests an effective spin $S = 1/2$ state per active Mo ion upon trimer disruption. These findings demonstrate that controlling non-magnetic cluster states within a polar host via chemical substitution is a promising approach for designing room-temperature magnetoelectric materials.

2605.21840 2026-05-22 astro-ph.GA

Powerful Radio Sources in the Southern Sky. IV. Observations of the G4Jy-3CRE Catalog with the Australian Square Kilometre Array Pathfinder

南天强大无线电源。IV. 使用澳大利亚平方公里阵列路径探测器对G4Jy-3CRE目录的观测

Siegfried A. Gawenda, Juan P. Madrid, Francesco Massaro, Sara V. White, C. C. Cheung, Chiara Mazzucchelli, Abigail García-Pérez, I. Andruchow, Vahram Chavushyan, Ralph Kraft, Victoria Reynaldi, Ana Jimenez-Gallardo, Alessandro Capetti, Barbara Balmaverde, William R. Forman, H. A. Peña-Herazo, Nicole Nesvadba, Sergio A. Cellone, Romana Grossová, Alessandro Paggi, Eleonara Sani, C. Leto

AI总结 本文通过ASKAP的连续波成像技术对G4Jy-3CRE目录中的源进行观测,确定了66%的源具有喷流形态,并识别出六个光学对应体,扩展了红移至z=1.35的FRI/FRII星系分类。

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AI中文摘要

最近的一篇2023年论文由Massaro等人发表,介绍了G4Jy-3CRE,这是一个新的南半球最亮无线电源目录,作为第三剑桥修订版(3CR)的南半球等价物。G4Jy-3CRE目录基于GLEAM-4Jy调查的相同标准选择了264个源。在本文中,我们使用澳大利亚平方公里阵列路径探测器(ASKAP)的连续波成像技术对G4Jy-3CRE目录进行了新的观测。我们使用了三个最近的数据发布版本,覆盖南纬+30°以南的天空:RACS-low1、RACS-mid和RACS-high。这些数据发布版本覆盖了从600到1800 MHz的频率范围。RACS调查在相同频率下比存档调查具有更高的空间分辨率和灵敏度,使我们能够对173个源(样本的66%)进行分类,这些源的形态表明存在喷流,其中37个源在存档无线电地图上未显示喷流活动。我们能够有效地将FRI/FRII星系分类到红移z=1.35。此外,我们识别出六个光学对应体,这些对应体要么之前未被识别,要么存在歧义。

英文摘要

A recent 2023 paper by Massaro et al. introduced the G4Jy-3CRE, a new catalog of the brightest radio sources in the southern hemisphere that serve as a southern equivalent to the Third Cambridge Catalog Revised (3CR). The G4Jy-3CRE catalog selected 264 sources from the GLEAM-4Jy survey based on the same criteria used to select the sources in the 3CR. In this paper, we present new Australian Square Kilometre Array Pathfinder (ASKAP) continuuum imaging of the G4Jy-3CRE catalog. We use the three most recent data releases from the Rapid ASKAP Continuum Survey (RACS), covering the sky south of +30°decl.: RACS-low1, RACS-mid, and RACS-high. Together, these data releases cover a range of frequencies from 600 to 1800 MHz. The RACS surveys have improved spatial resolution and sensitivity over archival surveys at the same frequency, enabling us to classify 173 sources (66% of the sample) with morphologies indicative of the presence of jets, 37 of which did not show jet activity on archival radio maps. We were able to effectively classify FRI/FRII galaxies up to a redshift of z = 1.35. Moreover, we identified six optical counterparts for sources that were either previously unidentified or ambiguous.

2605.21839 2026-05-22 physics.optics

Phase-edge imaging using q-plate shifts for faster and simpler microscopy

利用q-plate位移的相边成像用于更快更简单的显微镜

Jigme Zangpo, Hirokazu Kobayashi, Ryo Yasuhara

AI总结 本文提出了一种简化方法,利用4f系统和偏轴q-plate来分离相物体边缘与幅度物体边缘,通过仅需两个q-plate位移(沿±x方向)结合45度和135度线性偏振器,将测量次数减半,从而提高成像速度。理论推导表明,所得强度对应于相位梯度的平方,消除了幅度物体的贡献。实验显示,对两种相位-幅度物体样本的幅度边缘减少可达97.6%,相关系数分别达到0.78和0.75。在重叠区域,相边部分恢复,完全恢复需进一步处理如逆滤波。该研究适用于需要快速和简单相边分离的生物成像应用。

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AI中文摘要

我们提出了一种简化方法,利用4f系统和偏轴q-plate来分离相物体边缘与幅度物体边缘。与之前需要四个偏轴位移不同,我们仅需两个位移(沿±x方向)结合45度和135度的线性偏振器。测量次数减半,可能将获取速度加倍。我们推导了理论基础,表明所得强度对应于相位梯度的平方,幅度物体的贡献被消除。对两种相位-幅度物体样本的实验显示,幅度边缘减少可达97.6%,相关系数分别达到0.78(样本1)和0.75(样本2)。在重叠区域,相边部分恢复;完全恢复需要进一步处理,如逆滤波。该研究适用于需要快速和简单相边分离的生物成像应用。

英文摘要

We present a simplified method for isolating the edges of a phase object from the edges of an amplitude object using a 4f system with an off-axis q-plate. Instead of the four off-axis shifts of the q-plate required in previous work, we need only two shifts (along +/- x) combined with linear polarizers at 45 degrees and 135 degrees. The number of measurements is reduced by half, potentially doubling the acquisition speed. We derive the theoretical basis, showing that the resulting intensity corresponds to the phase gradient squared, with amplitude-object contributions eliminated. Experiments on two phase-amplitude object samples demonstrate amplitude-edge reduction up to 97.6% and correlation coefficients up to 0.78 (sample 1) and 0.75 (sample 2). In overlapping regions, the phase edge is partially recovered; full recovery would require additional processing such as inverse filtering. This research is useful for biological imaging applications where fast and simple phase-edge isolation is desired.

2605.21838 2026-05-22 hep-th gr-qc

New mechanism for fermion localization in $f(T,T_G)$-brane

$f(T,T_G)$膜中费米子局域化的新机制

Allan R. P. Moreira, Fernando M. Belchior, Guo-Hua Sun, Shi-Hai Dong

AI总结 本文研究了在修改的Teleparallel引力框架下,$f(T,T_G)$函数描述的五维膜世界场景中费米子场的局域化问题,通过非最小耦合Dirac旋量与 torsional 不变量,推导出有效的Schrödinger-like方程,揭示了Teleparallel Gauss-Bonnet项对有效势能和局域化性质的显著影响,并利用信息论量度量化局域化机制。

Comments 18 pages and 6 figures

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AI中文摘要

我们研究了在修改的Teleparallel引力框架下,由一般$f(T,T_G)$函数描述的五维膜世界场景中费米子场的局域化问题。考虑Dirac旋量与torsional不变量之间的非最小耦合,我们推导出支配Kaluza-Klein模的有效的Schrödinger-like方程。我们展示了Teleparallel Gauss-Bonnet项对有效势能的贡献显著改变了有效势能和局域化性质。零模分析表明,只有单个chiral分量可以局域化在膜上,其局域化程度取决于所选模型。在有质量的领域,谱是连续的,但由于势能的内部结构,共振态由于出现。此外,我们利用信息论量度,如Shannon熵和相对概率,来量化局域化机制。我们的结果表明,torsional修改诱导了信息的非平凡重新分布,表现出更强的局域化。这些发现突显了高阶torsional项在塑造膜世界场景中费米子局域化和共振结构中的作用。

英文摘要

We investigate the localization of fermionic fields in a five-dimensional braneworld scenario within the framework of modified teleparallel gravity described by a general $f(T,T_G)$ function. Considering a non-minimal coupling between a Dirac spinor and the torsional invariants, we derive the effective Schrödinger-like equations governing the Kaluza-Klein modes. We showed that the contribution of the teleparallel Gauss-Bonnet term significantly modifies the effective potentials and, consequently, the localization properties. The zero-mode analysis reveals that only one chiral component can be localized on the brane, with the degree of confinement depending on the chosen model. In the massive sector, the spectrum is continuous, but resonant states arise due to the internal structure of the potentials. Additionally, we employ information-theoretic measures, such as Shannon entropy and relative probability, to quantify the localization mechanism. Our results show that the torsional modifications induce a nontrivial redistribution of information, exhibiting stronger localization. These findings highlight the role of higher-order torsional terms in shaping fermionic localization and resonance structures in braneworld scenarios.