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2601.18627 2026-06-03 astro-ph.CO physics.data-an

Constraining reionization morphology and source properties with 21cm galaxy cross-correlation surveys

利用21厘米与星系交叉相关巡天约束再电离形态和源性质

Yannic Pietschke, Anne Hutter, Caroline Heneka

AI总结 通过模拟推断框架EoRFlow,量化21厘米与星系交叉功率谱对中性氢分数、平均过密度、电离源逃逸分数和恒星形成效率的约束能力,发现交叉相关可打破自功率谱中的简并,但需要高光谱红移精度和深场巡天。

Comments 12 pages, 6 figures, accepted for publication in A&A

Journal ref A&A 710, A113 (2026)

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AI中文摘要

21厘米观测与星系巡天之间的交叉相关通过提供对前景污染的鲁棒性,同时将电离形态与星系联系起来,为再电离提供了强大的探针。我们量化了21厘米星系交叉功率谱在推断中性氢分数$x_\mathrm{HI}(z)$和平均过密度$\langle 1+δ_\mathrm{HI} \rangle(z)$方面的约束能力,并探讨了其对视场、红移精度$σ_z$和最小暗晕质量$M_\mathrm{h,min}$的依赖性。我们采用基于模拟的推断框架EoRFlow进行无似然参数估计。模拟观测包括100小时SKA-Low的热噪声(含前景规避)以及真实的星系巡天效应。对于一个基准巡天($\mathrm{FOV}=100\,\mathrm{deg}^2$,$σ_z=0.001$,$M_\mathrm{h,min}=10^{11}\mathrm{M}_\odot$),交叉功率谱产生的后验体积(PV)相对于先验约为10%,提供无偏约束。与仅使用21厘米自功率谱相比,交叉功率测量将PV降低20-30%。在采用前景规避时,光谱红移精度至关重要;测光红移使交叉相关失去信息。值得注意的是,交叉功率谱约束了电离源性质——逃逸分数$f_\mathrm{esc}$和恒星形成效率$f_*$,而这些在自功率谱中仍然是简并的(PV >60%)。严格的约束需要要么探测到暗弱星系($M_\mathrm{h,min} \sim 10^{10}\mathrm{M}_\odot$)的深度巡天(中等前景,PV~11%),要么采用保守的质量极限和乐观的前景去除(PV~19%)。21厘米星系交叉相关增强了超出自功率谱的形态约束,同时实现了以前无法获得的源性质约束。充分发挥其潜力需要精确的红移以及暗弱星系探测极限或改进的21厘米前景清洁。

英文摘要

Cross-correlations between 21cm observations and galaxy surveys provide a powerful probe of reionization by providing robustness against foreground contamination while linking ionization morphology to galaxies. We quantified the constraining power of 21cm galaxy cross-power spectra for inferring the neutral hydrogen fraction, $x_\mathrm{HI}(z),$ and mean overdensity, $\langle 1+δ_\mathrm{HI} \rangle(z)$, exploring dependence on the field of view; redshift precision, $σ_z$; and minimum halo mass, $M_\mathrm{h,min}$. We employed our simulation-based inference framework EoRFlow for likelihood-free parameter estimation. Mock observations include thermal noise for 100h of SKA-Low with foreground avoidance and realistic galaxy-survey effects. For a fiducial survey ($\mathrm{FOV}=100\,\mathrm{deg}^2$, $σ_z=0.001$, $M_\mathrm{h,min}=10^{11}\mathrm{M}_\odot$), cross-power spectra yield unbiased constraints with posterior volumes (PVs) of $\sim$10% relative to priors. Cross-power measurements reduce the PV by 20-30% versus 21cm auto-power alone. With foreground avoidance, spectroscopic redshift precision is essential; photometric redshifts render cross-correlations uninformative. Notably, cross-power spectra constrain ionizing source properties, the escape fraction $f_\mathrm{esc,}$ and the star formation efficiency $f_*$, which remain degenerate in auto-power (PV >60%). Tight constraints require either deep surveys detecting faint galaxies ($M_\mathrm{h,min} \sim 10^{10}\mathrm{M}_\odot$) with moderate foregrounds (PV~11%) or conservative mass limits with optimistic foreground removal (PV~19%). 21cm galaxy cross-correlations enhance morphology constraints beyond auto-power while enabling previously inaccessible source property constraints. Realizing full potential requires precise redshifts and either faint galaxy detection limits or improved 21cm foreground cleaning.

2512.07053 2026-06-03 eess.SP cs.SY eess.SY

Random Access for LEO Satellite Communication Systems via Deep Learning

基于深度学习的低轨卫星通信系统随机接入

Hyunwoo Lee, Ian P. Roberts, Jinkyo Jeong, Daesik Hong

AI总结 针对低轨卫星通信中长传播延迟、大多普勒频移和大量并发接入挑战,提出基于深度学习的随机接入框架,利用多天线相关特征和轻量级1D卷积神经网络进行早期前导碰撞分类,并设计机会传输方案以平衡接入概率和资源效率,仿真验证了其在成功概率、时延、信道利用率和计算复杂度方面的优势。

Comments 13 pages, 13 figures, 5 tables

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AI中文摘要

将基于竞争的随机接入过程集成到低轨卫星通信系统中带来了新的挑战,包括长传播延迟、大多普勒频移以及大量同时接入尝试。这些因素降低了传统随机接入方案的效率和响应能力,特别是在基于卫星的物联网和直接到设备服务等场景中。在本文中,我们提出了一种为低轨卫星通信系统设计的基于深度学习的随机接入框架。该框架包含一个早期前导碰撞分类器,利用多天线相关特征和轻量级1D卷积神经网络在最早阶段估计碰撞用户数量。基于此估计,我们引入了一种机会传输方案,平衡接入概率和资源效率,以提高成功率和降低时延。在符合3GPP标准的低轨卫星设置下的仿真结果证实,与现有方案相比,所提框架实现了更高的接入成功概率、更低的时延、更好的物理上行共享信道利用率以及更低的计算复杂度。

英文摘要

Integrating contention-based random access procedures into low Earth orbit (LEO) satellite communication (SatCom) systems poses new challenges, including long propagation delays, large Doppler shifts, and a large number of simultaneous access attempts. These factors degrade the efficiency and responsiveness of conventional random access schemes, particularly in scenarios such as satellite-based internet of things and direct-to-device services. In this paper, we propose a deep learning-based random access framework designed for LEO SatCom systems. The framework incorporates an early preamble collision classifier that uses multi-antenna correlation features and a lightweight 1D convolutional neural network to estimate the number of collided users at the earliest stage. Based on this estimate, we introduce an opportunistic transmission scheme that balances access probability and resource efficiency to improve success rates and reduce delay. Simulation results under 3GPP-compliant LEO settings confirm that the proposed framework achieves higher access success probability, lower delay, better physical uplink shared channel utilization, and reduced computational complexity compared to existing schemes.

2505.12990 2026-06-03 quant-ph

From Theory to Practice: Analyzing Variational Quantum Power Method for Quantum Optimization of QUBO Problems

从理论到实践:分析用于QUBO问题量子优化的变分量子幂方法

Ammar Daskin

AI总结 本文对变分量子幂方法(VQPM)进行了全面的理论和数值分析,包括收敛性、鲁棒性和量子锁定机制,并提出了将其应用于QUBO问题的策略,通过与QAOA的对比实验和噪声模拟验证了其有效性。

Comments 19 pages, 11 figures. v3: IBM qiskit-aer noisy simulation is added. v4: The comparison sec. to QAOA rewritten and extended by using L-BFGS-B in the simulations of QAOA and adding scaling comparisons. All simulation code is publicly available at https://github.com/adaskin/vqpm

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AI中文摘要

变分量子幂方法(VQPM)将经典幂迭代算法适配到量子设置中,已在量子硬件上的特征向量估计和优化方面展现出潜力。在这项工作中,我们通过研究VQPM的收敛性、鲁棒性和量子锁定机制,对其进行了全面的理论和数值分析。我们提出了利用这些锁定机制将VQPM应用于QUBO问题的详细策略,建立了其实际应用的系统性指南。此外,我们与量子近似优化算法(QAOA)进行了比较研究。我们的分析评估了经典优化行为,并使用局部汉明距离(组合解的比特差异)评估性能。扩展到$n=18$量子比特的仿真表明,VQPM的成功概率表现出显著的韧性。最后,我们使用IBM Qiskit Aer框架在真实量子噪声下评估了VQPM。我们的结果表明,VQPM是一种有效的组合问题量子优化算法,这项工作可作为此类应用的初步指南。

英文摘要

The variational quantum power method (VQPM), which adapts the classical power iteration algorithm for quantum settings, has shown promise for eigenvector estimation and optimization on quantum hardware. In this work, we provide a comprehensive theoretical and numerical analysis of VQPM by investigating its convergence, robustness, and qubit locking mechanisms. We present detailed strategies for applying VQPM to QUBO problems by leveraging these locking mechanisms, establishing systematic guidelines for their practical applications. Furthermore, we provide a comparative study against the Quantum Approximate Optimization Algorithm (QAOA). Our analysis evaluates classical optimization behaviors and evaluates performance using localized Hamming distance (bit difference of the combinatorial solution). Scaling simulations up to $n=18$ qubits demonstrate that the success probability in VQPM exhibits notable resilience. Finally, we evaluate VQPM under realistic quantum noise using the IBM Qiskit Aer framework. Our results indicate that VQPM serves as an effective quantum optimization algorithm for combinatorial problems, and this work can serve as an initial guideline for such applications.

2601.16053 2026-06-03 math.AP math.OA

Fujita exponents on quantum Euclidean spaces

量子欧几里得空间上的Fujita指数

Edward McDonald, Michael Ruzhansky, Serikbol Shaimardan, Kanat Tulenov

AI总结 研究量子欧几里得空间上具有正初始数据的幂次非线性热方程的适定性,识别出区分小初始数据有限时间爆破与全局存在的临界指数,并建立一般半有限von Neumann代数中的基本不等式。

Comments 34 pages, corrected version. Comments welcome!

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AI中文摘要

我们研究量子欧几里得空间上具有正初始数据的幂次非线性热方程的适定性。通过识别区分小初始数据有限时间爆破与全局存在的临界指数,证明了经典Fujita定理的非交换类比。此外,我们在一般半有限von Neumann代数中建立了一个基本不等式,该不等式具有独立意义,并在非交换背景下研究非线性方程解的全局存在性和局部适定性中起着关键作用。

英文摘要

We study the well-posedness of a non-linear heat equation with power nonlinearity with positive initial data on quantum Euclidean spaces. We prove a noncommutative analogue of the classical Fujita theorem by identifying the critical exponent separating finite-time blow-up from global existence for small initial data. Moreover, we establish a fundamental inequality in general semifinite von Neumann algebras that is of independent interest and plays a crucial role in the study of global existence and local well-posedness of solutions of nonlinear equations in noncommutative setting.

2601.14886 2026-06-03 physics.plasm-ph

Piecewise omnigenous magnetohydrodynamic equilibria as fusion reactor candidates

分段全向磁流体动力学平衡作为聚变反应堆候选

V. Fernández-Pacheco, J. L. Velasco, E. Sánchez, R. Gaur, J. M. García-Regaña, J. A. Alonso, I. Calvo, D. Carralero

AI总结 本文提出一种满足理想磁流体动力学平衡方程的分段全向仿星器磁场配置,实现了前所未有的分段全向性,从而在降低径向输运、自举电流和快离子损失的同时保持磁流体动力学稳定性,满足可行聚变反应堆候选的物理标准。

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AI中文摘要

在分段全向磁场中,带电粒子在无碰撞和湍流的情况下保持完美约束。这一概念扩展了传统全向性的概念,而传统全向性是大多数现有磁聚变反应堆设计(包括托卡马克)所依据的理论原理。虽然分段全向性拓宽了潜在可行的仿星器反应堆候选范围,但它是通过放宽磁场强度连续性的要求来实现的,这似乎会给磁流体动力学平衡的设计带来重大挑战。在这项工作中,提出了一种满足理想磁流体动力学平衡方程的仿星器磁场配置,并实现了前所未有的分段全向性水平。因此,它表现出有利的输运特性,包括减少的体径向输运(新经典和湍流输运)、自举电流和快离子损失。此外,该配置在一系列β值下显示出稳健的磁流体动力学稳定性,并具有与岛偏滤器兼容的旋转变换剖面。总的来说,这些特征满足了可行反应堆候选所需的标准物理标准,而直到现在,人们认为只有某些类型的全向仿星器才能达到这些标准。

英文摘要

In piecewise omnigenous magnetic fields, charged particles remain perfectly confined in the abscence of collisions and turbulence. This concept extends the traditional notion of omnigenity, the theoretical principle upon which most of existing magnetic fusion reactor designs, including tokamaks, are based. While piecewise omnigenity broadens the range of potentially viable stellarator reactor candidates, it is achieved by relaxing the requirement of continuity in the magnetic field strength, which could appear to pose significant challenges for the design of magnetohydrodynamic equilibria. In this work, a stellarator magnetic configuration is presented that satisfies the ideal magnetohydrodynamic equilibrium equation and that achieves unprecedented levels of piecewise omnigenity. As a result, it exhibits favorable transport characteristics, including reduced bulk radial (neoclassical and turbulent transport), bootstrap current and fast ion losses. In addition, the configuration displays robust MHD stability across a range of \b{eta} values and possesses a rotational transform profile compatible with an island divertor. Collectively, these features satisfy the standard set of physics criteria required for a viable reactor candidate which, until now, were believed to be attainable only by certain types of omnigenous stellarators.

2601.14520 2026-06-03 cond-mat.soft

Diffusive buckling fronts in lattice-based metamaterials

基于格点的超材料中的扩散屈曲前沿

Jochem G. Meijer, Faadil H. Shaik, Victoria V. McDermott, Heinrich M. Jaeger

AI总结 本文通过实验和理论模型,研究了高耗散三维格点超材料中由压缩触发的屈曲失稳如何以扩散前沿形式传播,并建立了基于反应-扩散方程的可预测框架。

Comments 22 pages, 10 figures

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AI中文摘要

力学超材料可以设计成表现出独特的力学性能,包括可调的反常行为和多重稳定性,这些特性源于组成构建块的几何形状和配置。特别是基于格点的超材料,提供了轻量化的平台,其中局部不稳定性可以决定全局响应,应用于能量路由和振动隔离。在欠阻尼结构中,扰动已被发现以非线性波的形式传播,例如过渡波或孤子。在这里,我们研究了过阻尼、高耗散格点超材料的相反极限。聚焦于三维结构,我们揭示了由压缩触发的屈曲不稳定性如何以前沿形式传播,从而塑造宏观行为。我们在3D打印简单立方格点的实验中展示了如何通过格点几何控制全局和局部屈曲模式。通过将粘弹性耗散纳入三维连续介质模型,我们表明应变驱动的屈曲前沿服从耦合的反应-扩散方程。由局部几何、材料属性和应变决定的扩散和反应系数,选择了传播方向并能够引导前沿。这为基于格点的超材料中级联力学不稳定性的控制建立了一个可预测且经过实验验证的框架。

英文摘要

Mechanical metamaterials can be designed to exhibit unique mechanical properties, including tunable auxetic behavior as well as multi-stability, which arise from the geometry and configuration of the constituent building blocks. Lattice-based metamaterials, in particular, provide lightweight platforms where local instabilities can dictate the global response, with applications in energy routing and vibration isolation. In underdamped structures, perturbations have been found to propagate as nonlinear waves, e.g., transition waves or solitons. Here we investigate the opposite limit of overdamped, highly dissipative lattice metamaterials. Focusing on three-dimensional structures, we uncover how buckling instabilities, triggered by compression, propagate as fronts that shape the macroscopic behavior. We demonstrate in experiments on 3D-printed simple cubic lattices how global and local buckling modes can be controlled via the lattice geometry. By incorporating viscoelastic dissipation into a 3D-continuum model, we show that strain-driven buckling fronts obey coupled reaction-diffusion equations. The diffusion and reaction coefficients, determined by local geometry, material properties, and strain, select the propagation direction and enable steering of the fronts. This establishes a predictive and experimentally validated framework for the control of cascading mechanical instabilities in lattice-based metamaterials.

2601.07432 2026-06-03 physics.soc-ph

Extending the Biswas--Chatterjee--Sen model with nonconformists and inflexibles

扩展Biswas--Chatterjee--Sen模型以包含非从众者和顽固者

Amit Pradhan, Parongama Sen, Krzysztof Malarz

AI总结 通过引入非从众者和顽固者扩展Biswas-Chatterjee-Sen模型,使用蒙特卡洛模拟和平均场计算研究他们对系统平均观点的影响,发现非从众者比例的有序相区间,以及顽固者对无序相的抑制效应。

Comments 13 pages, 10 figures

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AI中文摘要

最初,Biswas--Chatterjee--Sen模型被证明在足够多的负相互作用下表现出有序/无序相变。本文通过引入反从众者和顽固者来扩展该模型。反从众者是那些自我定义与群体对立,并可能故意拒绝大多数人所接受观点的人,而顽固者是那些完全不改变自己观点的人。考虑了离散和连续观点。通过直接蒙特卡洛模拟和平均场计算,我们检查了反从众者和顽固者比例对系统中平均观点的影响。通过平均场计算,我们确定了系统有序相可用的反从众者比例范围。平均场计算的结果与蒙特卡洛模拟的结果完全吻合。我们考虑了顽固者坚持:(i)极端观点;(ii)特定观点;(iii)独立于其初始观点选择。对于坚持特定和极端观点的顽固者,他们起到了有效偏置的作用,抑制了系统中的无序相。以不同方式(离散/连续观点和退火/淬火无序)引入反从众者(顽固者)的定性结果大致相同。然而,对于由顽固者扩展的模型,我们可以观察到与退火无序相比,淬火无序下平均序参数系统性地向更高值偏移。另一方面,对于用连续观点空间建模的反从众者,我们可以观察到与离散观点空间相比,平均序参数系统性地向更高值偏移。

英文摘要

Originally, the Biswas--Chatterjee--Sen model was shown to exhibit an order/disorder phase transition for a sufficiently large number of negative interactions among actors. In this paper, the model is extended by the existence of anticonformists and inflexibles. Anticonformists are actors who define themselves in opposition to the group and may intentionally reject what most people accept, while inflexibles are those who do not change their opinions at all. Both discrete and continuous opinions are considered. With direct Monte Carlo simulations and mean-field calculations, we check the influence of fractions of anticonformists and inflexibles on the mean opinion in the system. With the mean-field calculations, we identify ranges of fractions of anticonformists where an ordered phase of the system is available. The results of the mean-field calculations perfectly match the results of the Monte Carlo simulations. We consider inflexibles adhered: (i) to extreme opinions; (ii) to specific opinions, and (iii) chosen independently of their initial opinion. For inflexibles adhered to specific and extreme opinions, they play a role of an effective bias suppressing the disordered phase in the system. The qualitative results of introducing anticonformists (inflexibles) in various ways (discrete/continuous opinions and annealed/quenched disorder) are roughly the same. However, for the model extended by inflexibles, we can observe a systematic shift of the mean order parameter to its higher values for quenched disorder compared with annealed disorder. On the other hand, for anticonformists modeled with a continuous space of opinions, we can observe a systematic shift of the mean order parameter to its higher values compared with the discrete space of opinions.

2511.16257 2026-06-03 math.CV math.AG

Subtlety of oscillation indices of oscillatory integrals of real analytic functions

实解析函数振荡积分的振荡指数的微妙性

In-Kyun Kim, Morihiko Saito

AI总结 研究局部实解析函数振荡积分的振荡指数与实对数规范阈值的关系,给出等式成立或失败的充分条件,并指出在牛顿非退化齐次情形下存在与文献标准公式不符的结论。

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AI中文摘要

对于局部定义的实解析函数 $f$,我们研究振荡积分的振荡指数与实对数规范阈值之间的关系。前者总是负的,其绝对值大于或等于后者。它们通常相等,但存在某些例外情况,且等号成立的条件并不十分清楚。在本文中,我们给出了一些等号成立或失败的充分条件。在牛顿非退化齐次情形下,我们证明:如果变量个数 $n$ 为偶数且小于 $f$ 的次数 $d$(或 $f^{-1}(0)=\{0\}$),则严格不等式成立;如果 $n$ 为奇数且 $f^{-1}(0)=\{0\}$(特别地,$d$ 为偶数),则等号成立。第一个断言似乎与文献中的某些标准公式不相容,尽管在本文中不易发现错误,但必定存在某些错误。

英文摘要

For a locally defined real analytic function $f$, we study the relation between the oscillation index of oscillatory integrals and the real log canonical threshold. The former is always negative, and its absolute value is greater than or equal to the latter. They coincide very often, but there are certain exceptional cases, and it is not very clear when the equality holds. In this note we give some sufficient conditions for the coincidence to hold or to fail. In the Newton-nondegenerate convenient homogeneous case, we show that the strict inequality holds if the number of variables $n$ is even and smaller than the degree $d$ of $f$ (or $f^{-1}(0)=\{0\}$), and the equality holds if $n$ is odd and $f^{-1}(0)=\{0\}$ (in particular, $d$ is even). The first assertion does not seem to be compatible with some standard formula in the literature, and there must be some error somewhere, although it does not seem easy to detect it inside this paper.

2601.12441 2026-06-03 cs.CY econ.GN q-fin.EC

The Dynamic and Endogenous Behavior of Re-Offense Risk: An Agent-Based Simulation Study of Treatment Allocation in Incarceration Diversion Programs

再犯风险的动态与内生行为:基于智能体的监禁分流项目治疗分配模拟研究

Chuwen Zhang, Pengyi Shi, Amy Ward

AI总结 通过基于智能体的模拟,研究再犯风险作为人-系统交互的动态过程,评估不同治疗分配策略在监禁分流项目中的有效性。

Comments Upon further review, we believe the manuscript requires substantial rethinking before its results can be presented in a fair and responsible manner in a sensitive field such as criminal justice. Given the potential implications of the work, we have decided that withdrawing the current version is the most appropriate course of action

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AI中文摘要

监禁分流治疗项目旨在改善社会融合并减少再犯,但有限的能力迫使政策制定者做出优先级决策,这些决策通常依赖于风险评估工具。尽管这些工具具有预测性,但它们通常将风险视为静态的个人属性,忽视了风险如何随时间演变以及治疗决策如何通过社会互动塑造结果。在本文中,我们开发了一个新框架,将再犯风险建模为人-系统交互,将个体行为与系统层面的动态和内生社区反馈联系起来。使用基于美国缓刑数据校准的智能体模拟,我们评估了不同能力约束和监禁环境下的治疗分配政策。我们的结果表明,没有单一的优先级政策占主导地位。相反,政策有效性取决于时间窗口和系统参数:当长期轨迹重要时,优先考虑低风险个体表现更好;而在短期内或当监禁导致更短的监控期时,优先考虑高风险个体更有效。这些发现强调了需要将基于风险的决策系统评估为具有长期责任的社会技术系统,而不是孤立的预测工具。

英文摘要

Incarceration-diversion treatment programs aim to improve societal reintegration and reduce recidivism, but limited capacity forces policymakers to make prioritization decisions that often rely on risk assessment tools. While predictive, these tools typically treat risk as a static, individual attribute, which overlooks how risk evolves over time and how treatment decisions shape outcomes through social interactions. In this paper, we develop a new framework that models reoffending risk as a human-system interaction, linking individual behavior with system-level dynamics and endogenous community feedback. Using an agent-based simulation calibrated to U.S. probation data, we evaluate treatment allocation policies under different capacity constraints and incarceration settings. Our results show that no single prioritization policy dominates. Instead, policy effectiveness depends on temporal windows and system parameters: prioritizing low-risk individuals performs better when long-term trajectories matter, while prioritizing high-risk individuals becomes more effective in the short term or when incarceration leads to shorter monitoring periods. These findings highlight the need to evaluate risk-based decision systems as sociotechnical systems with long-term accountability, rather than as isolated predictive tools.

2601.11223 2026-06-03 astro-ph.CO astro-ph.HE

KiDS-Legacy: WIMP dark matter constraints from the cross-correlation of weak lensing and Fermi-LAT gamma rays

KiDS-Legacy: 弱引力透镜与Fermi-LAT伽马射线互相关对WIMP暗物质的约束

Shiyang Zhang, Hendrik Hildebrandt, Ziang Yan, Tilman Tröster, Athithya Aravinthan, Marika Asgari, Deaglan J. Bartlett, Maciej Bilicki, Dominik Elsässer, Catherine Heymans, Benjamin Joachimi, Lauro Moscardini, Dennis Neumann, Anya Paopiamsap, Robert Reischke, Benjamin Stölzner

AI总结 通过分析KiDS-Legacy弱透镜剪切与Fermi-LAT未分辨伽马射线背景的互相关,未探测到显著信号,从而给出WIMP暗物质衰变率和湮灭截面的95%上限,并预测未来Euclid巡天可将约束提升约2倍。

Comments 18 pages, 13 figures, submitted to A&A

Journal ref A&A 710, A80 (2026)

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AI中文摘要

暗物质主导了宇宙的物质含量,其性质可以通过大尺度结构探针(如未分辨伽马射线背景(UGRB)与弱引力透镜的互相关)来约束。我们分析了15年的Fermi-LAT数据,构建了十个能段(0.5-1000 GeV)的UGRB强度图,并将其与KiDS-Legacy剪切在六个层析分箱中进行互相关。测量使用伪$C_\ell$方法估计角功率谱。未发现显著的互相关信号。基于这一未探测结果,我们给出了弱相互作用大质量粒子(WIMP)衰变率$\Gamma_{\rm dec}$和速度平均湮灭截面$\langle\sigma_{\rm ann} v\rangle$作为质量函数的95%上限。我们将结果与其他宇宙学示踪剂和本地探针的约束进行比较,发现它们具有互补性,特别是在低质量($\rm GeV/TeV$)区域。此外,使用类似Euclid的透镜巡天与Fermi-LAT互相关,我们预测约束可收紧约2倍,凸显了未来数据在加强暗物质湮灭和衰变约束方面的潜力。

英文摘要

Dark matter dominates the matter content of the Universe, and its properties can be constrained through large-scale structure probes such as the cross-correlation between the unresolved gamma-ray background (UGRB) and weak gravitational lensing. We analysed 15 years of Fermi-LAT data, constructing UGRB intensity maps in ten energy bins (0.5-1000 GeV), and cross-correlated them with KiDS-Legacy shear in six tomographic bins. The measurements were performed using angular power spectra estimated with the pseudo-$C_\ell$ method. No significant cross-correlation is found. Based on this non-detection, we present 95% upper bounds on the weakly interacting massive particle (WIMP) decay rate $Γ_{\rm dec}$ and velocity-averaged annihilation cross-section $\langleσ_{\rm ann} v\rangle$ as functions of mass. We compare our results with bounds from other cosmological tracers and from local probes, and found them to be complementary, particularly at low masses ($\rm GeV/TeV$). In addition, using a Euclid-like lensing survey cross-correlated with Fermi-LAT, we forecast $\sim$2 times tighter limits, highlighting the potential of forthcoming data to strengthen constraints on dark matter annihilation and decay.

2512.06016 2026-06-03 hep-ph

Diquark size effects in the quark-diquark approximation for baryons

重子夸克-双夸克近似中的双夸克尺寸效应

Clara Tourbez, Cyrille Chevalier, Claude Semay

AI总结 通过比较夸克-双夸克模型与三体模型,评估了重子夸克-双夸克近似的精度,并提出了改进该近似精度的新方法,发现双夸克不必紧凑即可获得良好的重子质量。

Comments Some clarifications have been added

Journal ref Eur. Phys. J. A 62 (2026) 101

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AI中文摘要

重子可以在几个理论框架内描述。其中,组分方法被广泛使用。在此背景下,我们旨在评估重子的一种特定模型——夸克-双夸克近似的精度。该近似将三体系统分解为两个连续的两体系统:一对夸克(双夸克)以及由双夸克和第三个夸克组成的第二个系统。这种近似被广泛使用,但其精度很少被评估。本工作的目标是通过将夸克-双夸克模型与三体模型进行比较来进行评估,两者使用相同的半相对论相互作用。在两种方法中计算并分析了重子质量和一些特征距离。此外,将提出一种建立夸克-双夸克势的原始程序,旨在提高该近似的精度。结果表明,为了获得良好的重子质量,双夸克不一定必须是紧凑的。

英文摘要

Baryons can be described within several theoretical frameworks. Among them, the constituent approach is widely used. In this context, we aim to evaluate the accuracy of a particular model of baryons: the quark-diquark approximation. It consists in separating the three-body system into two subsequent two-body ones: a pair of two quarks, the diquark, and a second system consisting of the diquark and the third quark. This approximation is widely used, but its accuracy is rarely evaluated. The goal of this work is to perform this evaluation by comparing the quark-diquark model with a three-body model, both using the same semi-relativistic interaction. The baryon masses and some characteristic distances are computed and analysed within both approaches. Additionally, an original procedure to establish the quark-diquark potential will be presented with the aim to increase the precision of this approximation. It is shown that a diquark must not necessarily be compact to obtain good baryon masses.

2509.15847 2026-06-03 cs.DC cs.CR

Angelfish: Leader, DAG, or Anywhere in Between

Angelfish: 领导者、DAG 或介于两者之间

Qianyu Yu, Giuliano Losa, Nibesh Shrestha, Xuechao Wang

AI总结 提出 Angelfish 混合共识协议,通过动态调整部分节点使用尽力广播替代可靠广播,在基于领导者和基于 DAG 的共识之间平滑过渡,兼顾低延迟和高吞吐量。

Comments Full version of CCS paper

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AI中文摘要

为了最大化性能,许多现代区块链系统依赖于最终同步的拜占庭容错(BFT)共识协议。该领域出现了两种协议设计:一种使用领导者驱动数据传播和共识以最小化延迟,另一种使用独立的异步数据传播层以最大化吞吐量。最近的协议如 Partially-Synchronous Bullshark 和 Sailfish 通过使用 DAG 实现并行数据传播和领导者控制 DAG 形成,结合了两种方法的元素。这改善了延迟,同时达到了最先进的吞吐量。然而,基于领导者的协议在中等负载下(实践中常见)的延迟仍然更好。我们提出 Angelfish,一种混合协议,能够在此设计空间中平滑适应,从基于领导者到类似 Sailfish 的基于 DAG 的共识。Angelfish 让动态调整的部分节点使用尽力广播发出轻量级投票,而不是可靠广播更昂贵的 DAG 顶点。这减少了通信,帮助落后节点追赶,并在实践中相比先前的基于 DAG 的协议降低了延迟。我们的实证评估表明,Angelfish 达到了最先进的峰值吞吐量,同时在中等吞吐量下显著降低延迟,实现了两全其美。

英文摘要

To maximize performance, many modern blockchain systems rely on eventually-synchronous, Byzantine fault-tolerant (BFT) consensus protocols. Two protocol designs have emerged in this space: protocols that minimize latency using a leader that drives both data dissemination and consensus, and protocols that maximize throughput using a separate, asynchronous data dissemination layer. Recent protocols such as Partially-Synchronous Bullshark and Sailfish combine elements of both approaches by using a DAG to enable parallel data dissemination and a leader that paces DAG formation. This improves latency while achieving state-of-the-art throughput. Yet the latency of leader-based protocols is still better under moderate loads, which are common in practice. We present Angelfish, a hybrid protocol that adapts smoothly across this design space, from leader-based to Sailfish-like DAG-based consensus. Angelfish lets a dynamically adjusted subset of parties use best-effort broadcast to issue lightweight votes instead of reliably broadcasting costlier DAG vertices. This reduces communication, helps lagging nodes catch up, and lowers latency in practice compared to prior DAG-based protocols. Our empirical evaluation shows that Angelfish attains state-of-the-art peak throughput while significantly lowering latency under moderate throughput, delivering the best of both worlds.

2601.10853 2026-06-03 cond-mat.other

Hopfions in screw chiral magnets

螺旋手性磁体中的霍普夫子

Sandra C Shaju, Maria Azhar, Karin Everschor-Sitte

AI总结 本文提出对称变换磁模型,在铁磁背景下稳定霍普夫子等三维拓扑自旋纹理,并揭示其非传统戈德斯通模等独特物理性质。

Comments 11 pages

Journal ref APL Mater. 14, 051111 (2026)

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AI中文摘要

三维拓扑自旋纹理因其丰富的几何结构和潜在的功能磁现象而日益受到关注。在这项工作中,我们提出了对称变换磁模型的概念,作为在任意磁背景中生成和稳定复杂三维纹理的新途径。利用这一框架,我们预测了一个螺旋手性磁体模型,该模型在铁磁背景下稳定了磁霍普夫子和其他三维磁纹理。我们表明,由此产生的孤子展现出独特的物理性质,包括非传统的戈德斯通模。我们的结果确立了连续对称变换作为发现具有独特动力学特征的新型磁孤子的一般策略。

英文摘要

Three-dimensional topological spin textures have attracted growing interest due to their rich geometry and potential for functional magnetic phenomena. In this work, we propose the concept of symmetry-transforming magnetic models as a novel route to generate and stabilize complex three-dimensional textures in an arbitrary magnetic background. Using this framework, we predict a screw chiral magnet model that stabilizes magnetic Hopfions and other three-dimensional magnetic textures within a ferromagnetic background. We show that the resulting solitons display distinctive physical properties, including unconventional Goldstone modes. Our results establish continuous symmetry transformations as a general strategy for uncovering new classes of magnetic solitons with unique dynamical signatures.

2601.10754 2026-06-03 cs.CR cs.CY cs.HC

Chatting with Confidants or Corporations? Privacy Management with AI Companions

与知己还是公司聊天?AI伴侣的隐私管理

Hsuen-Chi Chiu, Jeremy Foote

AI总结 基于沟通隐私管理理论和水平-垂直隐私框架,通过访谈Replika和Character.AI用户,发现用户融合人际习惯与机构意识,采用分层策略管理隐私,但拟人化设计导致边界模糊和隐私动荡。

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AI中文摘要

设计为情感伴侣的AI聊天机器人模糊了人际亲密与机构软件之间的界限,创造了复杂、多维的隐私环境。借鉴沟通隐私管理理论和Masur的水平(用户-AI)与垂直(用户-平台)隐私框架,我们对Replika和Character.AI等伴侣AI平台的十五名用户进行了深度访谈。我们的发现表明,用户将人际习惯与机构意识融合:虽然聊天机器人的非评判性、随时可用特性培养了情感安全感并鼓励自我披露,但用户仍然意识到机构风险,并通过分层策略和选择性分享积极管理隐私。尽管如此,许多人对平台层面的数据控制感到不确定或无力。拟人化设计进一步模糊了隐私边界,有时导致无意的过度分享和隐私动荡。这些结果通过强调人类-AI伴侣中情感与机构隐私管理的独特相互作用,扩展了隐私理论。

英文摘要

AI chatbots designed as emotional companions blur the boundaries between interpersonal intimacy and institutional software, creating a complex, multi-dimensional privacy environment. Drawing on Communication Privacy Management theory and Masur's horizontal (user-AI) and vertical (user-platform) privacy framework, we conducted in-depth interviews with fifteen users of companion AI platforms such as Replika and Character.AI. Our findings reveal that users blend interpersonal habits with institutional awareness: while the non-judgmental, always-available nature of chatbots fosters emotional safety and encourages self-disclosure, users remain mindful of institutional risks and actively manage privacy through layered strategies and selective sharing. Despite this, many feel uncertain or powerless regarding platform-level data control. Anthropomorphic design further blurs privacy boundaries, sometimes leading to unintentional oversharing and privacy turbulence. These results extend privacy theory by highlighting the unique interplay of emotional and institutional privacy management in human-AI companionship.

2512.10465 2026-06-03 quant-ph

Optimal Distributed Similarity Estimation of Quantum Channels

量子信道的最优分布式相似性估计

Congcong Zheng, Kun Wang, Xutao Yu, Ping Xu, Zaichen Zhang

AI总结 针对两个未知量子信道的比较问题,提出分布式相似性估计任务,并证明其最优查询复杂度为Θ(max{√d/ε, 1/ε²}),通过随机测量算法实现匹配上界。

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AI中文摘要

随着量子处理器部署在不同的硬件平台和远程云实验室中,一个基本的物理问题是:在不依赖可信经典描述的情况下,两个黑盒设备是否实现相同的量子过程。我们将此比较任务的核心原语表述为\emph{量子信道的分布式相似性估计}(DSEC):在本地访问两个未知信道的情况下,估计其Choi状态的归一化内积。我们证明DSEC的最优查询复杂度为$Θ(\max\{\sqrt{d}/\varepsilon,1/\varepsilon^2\})$,其中$d$是信道维度,$\varepsilon$是加性误差。这一匹配的查询复杂度是非平凡的:信道学习允许输入选择和交错已知操作,这使得信道学习严格比状态学习更难。我们首先证明了具有该缩放的信息论下界,即使在\emph{最强设置}下也成立,允许自适应策略、多轮经典通信以及任意辅助的相干访问。然后,我们在\emph{最弱设置}下给出了匹配的上界,即非自适应且无辅助的非相干访问,通过一个达到该界的随机测量算法实现。最后,我们展示了我们的算法相比经典阴影基线实现了二次改进。我们的结果为量子设备基准测试和分布式量子学习提供了理论上最优且实用的算法。

英文摘要

As quantum processors are deployed across different hardware platforms and remote cloud laboratories, a basic physical question is whether two black-box devices realize the same quantum process, without relying on a trusted classical description. We formulate the core primitive for this comparison task as \emph{distributed similarity estimation of quantum channels} (DSEC): given local access to two unknown channels, estimate the normalized inner product of their Choi states. We prove that the optimal query complexity of DSEC is $Θ(\max\{\sqrt{d}/\varepsilon,1/\varepsilon^2\})$, where $d$ is the channel dimension and $\varepsilon$ is the additive error. This matching query complexity is nontrivial: channel learning permits input choices and interleaving known operations, which makes channel learning strictly harder than state learning. We first prove an information-theoretic lower bound with this scaling, which holds even in the \emph{strongest setting}, allowing adaptive strategies, multiple rounds of classical communication, and coherent access with arbitrary ancillas. We then give a matching upper bound in the \emph{weakest setting}, namely non-adaptive and ancilla-free incoherent access, via a randomized measurement algorithm achieving this bound. Finally, we show that our algorithm achieves a quadratic improvement over classical shadow baselines. Our results provide theoretically optimal and practical algorithms for quantum device benchmarking and distributed quantum learning.

2601.09542 2026-06-03 hep-ph hep-th

Modulus stabilization of modular flavor models in Jordan frame supergravity

Jordan 标架超引力中模组味模型的模稳定化

Fei Wang, Ying Kai Zhang

AI总结 本文在 Jordan 标架超引力中,通过非最小标量-曲率耦合形式 $Φ(τ,\barτ)R$,结合模不变性、尺度因子正定性和 Kähler 度规正定性,约束标架函数及 Kähler 势,并研究从 Jordan 标架到 Einstein 标架变换后标量势的形状,发现其与普通单模稳定化机制不同,势能在 $i\infty$ 不动点处可能静止导致逃逸型真空,但可通过典型模 VEV 在大 $\Imτ$ 下稳定,最后数值讨论了简化场景下的模稳定化。

Comments Minor changes, discussions added; 31 pages, 3 figures

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AI中文摘要

我们提出在 Jordan 标架超引力中讨论模组味模型和单模场的稳定化,其中非最小标量-曲率耦合形式为 $Φ(τ,\barτ)R$。模不变性、尺度因子的正定性以及 Kähler 度规的正定性严格约束了标架函数的形式,进而通过关系 $Φ(τ,\barτ)=-3\exp[-K(τ,\barτ)/3]$ 约束了 Kähler 势。我们讨论了从 Jordan 标架到 Einstein 标架进行尺度变换后标量势的一些一般性质。我们发现,Einstein 标架中得到的标量势的形状与普通单模稳定化机制有很大不同。标量势在 $i\infty$ 不动点处可能是静止的,导致逃逸型真空。这种逃逸型真空可以在具有大 $\Imτ$ 的典型模 VEV 处得到适当稳定。我们还数值讨论了一些简化场景下的模稳定化。

英文摘要

We propose to discuss the modular flavor model and the stabilization of single modulus field in the Jordan frame supergravity with non-minimal scalar-curvature coupling of the form $Φ(τ,\barτ)R$. Modular invariance, positivity of the scale factor and positive definiteness of the Kahler metric constrain stringently the form of the frame function, consequently the Kahler potential by the relation $Φ(τ,\barτ)=-3\exp[-K(τ,\barτ)/3]$. We discuss some general properties of scalar potentials after the scale transformation from the Jordan frame to the Einstein frame. We find that the shape of the resulting scalar potential in the Einstein frame is quite different from that of ordinary single modulus stabilization mechanism. The scalar potential could be stationary at the $i\infty$ fixed point, leading to a runaway type vacuum. Such a runaway-type vacuum can be properly stabilized at typical modulus VEV with large $\Imτ$. We also discuss numerically the modulus stabilization for some simplified scenarios.

2601.08675 2026-06-03 astro-ph.CO gr-qc hep-th

One-Loop Tensor Power Spectrum from a Non-Canonical Spectator Field during Inflation

非正则旁观者场在暴胀期间的单圈张量功率谱

Zhe Li, Chen Yuan, Qing-Guo Huang

AI总结 利用in-in形式计算了非正则旁观者场暴胀场景下张量功率谱的单圈修正,发现局域高斯耦合导致有效张标比$r_{\mathrm{eff}}$的$\mathcal{O}(1)$修正,而快速振荡耦合可将其提高数个数量级。

Comments 12 pages, 5 figures, accepted by JCAP

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AI中文摘要

我们使用in-in形式计算了具有{非正则旁观者场}的暴胀场景中原始张量功率谱的全单圈修正。我们推导了标量源单圈张量谱和有效张标比$r_{\mathrm{eff}}$的半解析结果。我们考虑了两个代表性的耦合函数:局域高斯凹陷(模型G),它导致适度的圈修正;以及快速振荡耦合(模型O),它可以产生更大的圈贡献。对于模型G,我们发现$r_{\mathrm{eff}}$有$\mathcal{O}(1)$的修正,而模型O可以显著增强$r_{\mathrm{eff}}$数个数量级(相对于树图级值)。我们进一步计算了原始引力波的能量密度。假设在此场景中产生的质量为$10^{-12}M_{\odot}$的原初黑洞构成了所有暗物质,我们发现结果比Taiji/TianQin/LISA的灵敏度低数个数量级。

英文摘要

We compute the full one-loop corrections to the primordial tensor power spectrum in an inflationary scenario with a {non-canonical spectator field}, using the in-in formalism. We derive semi-analytic results for the scalar-sourced one-loop tensor spectrum and the effective tensor-to-scalar ratio, $r_{\mathrm{eff}}$. We consider two representative coupling functions: a localized Gaussian dip (Model G), which leads to moderate loop corrections, and a rapidly oscillatory coupling (Model O), which can yield much larger loop contributions. For Model G, we find a $\mathcal{O}(1)$ correction to $r_{\mathrm{eff}}$ while Model O can significantly enhance $r_{\mathrm{eff}}$ by several orders of magnitude (relative to the tree-level value). We further calculate the energy density of primordial gravitational waves. Assuming that primordial black holes with mass $10^{-12}M_{\odot}$ generated in this scenario, constitute all of the dark matter, we find that the results are several orders of magnitude lower than the sensitivities of Taiji/TianQin/LISA.

2601.08650 2026-06-03 math.AP math.PR

Subdiffusive fractional limit of a jump-renewal equation

跳跃更新方程的子扩散分数阶极限

Hugues Berry, Pierre Gabriel, Thomas Lepoutre, Nathan Quiblier

AI总结 本文考虑年龄结构跳跃模型,证明在适当重标度下,该方程在长时间大尺度极限下收敛到时间分数阶子扩散方程。

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AI中文摘要

在本文中,我们考虑一个年龄结构跳跃模型,该模型作为跳跃间等待时间具有无限均值的连续时间随机游走的描述出现。我们证明,在适当重标度下,该方程在长时间大尺度极限下收敛到时间分数阶子扩散方程。

英文摘要

In this paper, we consider an age-structured jump model that arises as a description of continuous time random walks with infinite mean waiting time between jumps. We prove that under a suitable rescaling, this equation converges in the long time large scale limit to a time fractional subdiffusion equation.

2510.12028 2026-06-03 econ.TH cs.GT

Perceived Fairness in Networks

网络中的感知公平

Arthur Charpentier

AI总结 研究个体通过社交网络局部感知公平的模型,发现即使决策规则满足全局公平标准,同质性或分类混合仍可能导致感知歧视持续或加剧。

Journal ref Net Sci 14 (2026) e11

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AI中文摘要

算法公平的通常定义关注人口层面的统计量,如人口均等或机会均等。然而,在许多社会或经济背景下,公平并非全局感知,而是通过个体的同伴网络和比较局部感知。我们提出了一个感知公平网络的理论模型,其中每个个体的歧视感取决于互动的局部拓扑。我们证明,即使决策规则满足标准的公平准则,在同质性或分类混合存在的情况下,感知歧视仍可能持续甚至加剧。我们提出了公平感知概念的形式化,将网络结构、局部观察和社会感知联系起来。分析和模拟结果突出了网络拓扑如何影响客观公平与感知公平之间的分歧,对算法治理以及金融和协作保险中的应用具有启示意义。

英文摘要

The usual definitions of algorithmic fairness focus on population-level statistics, such as demographic parity or equal opportunity. However, in many social or economic contexts, fairness is not perceived globally, but locally, through an individual's peer network and comparisons. We propose a theoretical model of perceived fairness networks, in which each individual's sense of discrimination depends on the local topology of interactions. We show that even if a decision rule satisfies standard criteria of fairness, perceived discrimination can persist or even increase in the presence of homophily or assortative mixing. We propose a formalism for the concept of fairness perception, linking network structure, local observation, and social perception. Analytical and simulation results highlight how network topology affects the divergence between objective fairness and perceived fairness, with implications for algorithmic governance and applications in finance and collaborative insurance.

2601.05846 2026-06-03 cond-mat.quant-gas physics.atom-ph

Vorticity-Crystalline Order Coupling in Supersolids: Excitations and Re-entrant Phases

超固体中的涡度-晶序耦合:激发与重入相

Malte Schubert, Koushik Mukherjee, Philipp Stürmer, Stephanie Reimann

AI总结 通过理论计算,研究旋转频率而非相互作用对玻色-爱因斯坦凝聚体中超流-超固体转变的调控,发现量子涡度将无隙戈德斯通模提升为有限能量旋子,导致重入超固体相,揭示拓扑缺陷与晶序的基本耦合。

Comments 9 pages, 5 figures

Journal ref Phys. Rev. Lett. 136, 183401 (2026)

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AI中文摘要

旋转是超冷气体中打破时间反演对称性的自然工具,但其对超固体集体激发的影响尚未被充分探索。我们从理论上表明,调节旋转频率而非粒子间相互作用可以触发玻色-爱因斯坦凝聚体(dBECs)中的超流-超固体转变。通过计算存在涡旋和持续流时的激发谱,我们揭示了一种涡旋驱动的去软化机制,其中量子涡度将无隙戈德斯通模提升为有限能量的旋子,从而恢复超流性。这种效应导致随旋转频率变化的重入超固体相,揭示了拓扑缺陷与晶序之间的基本耦合。

英文摘要

Rotation is a natural tool in ultracold gases to break time-reversal symmetry, yet its impact on the collective excitations of supersolids remains largely unexplored. We show theoretically that tuning the rotation frequency, rather than the interparticle interactions, can trigger the superfluid-to-supersolid transition in Bose-Einstein condensates (dBECs). Computing excitation spectra in the presence of vortices and persistent currents, we uncover a vortex-driven de-softening mechanism whereby quantized vorticity elevates the gapless Goldstone mode to a finite-energy roton, restoring superfluidity. This effect results in re-entrant supersolid phases as a function of rotation frequency, revealing a fundamental coupling between topological defects and crystalline order.

2507.03587 2026-06-03 quant-ph

Analog Circuit-QED Simulator of Quantum Spin Dynamics Through the Extended Bose-Hubbard Model

通过扩展Bose-Hubbard模型的模拟量子自旋动力学的模拟电路QED

Ivan V. Dudinets, Jaehee Kim, Tomás Ramos, Aleksey K. Fedorov, Vladimir I. Man'ko, Joonsuk Huh

AI总结 提出并验证了一种利用电路量子电动力学平台模拟海森堡自旋模型的框架,通过扩展Bose-Hubbard模型实现,数值模拟证实微波光子动力学准确再现自旋动力学。

Comments 6 figures, 19 pages

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AI中文摘要

我们提出并验证了一个利用电路量子电动力学(circuit-QED)平台模拟海森堡自旋模型的框架。为此,我们发展了一族连续的SU(2)代数变形玻色子表示,其中包括Holstein-Primakoff和Dyson-Maleev变换作为特例。对于自旋-1/2系统,我们引入了一种方法来规避该表示固有的非厄米性,表明整个族都产生扩展Bose-Hubbard(EBH)哈密顿量。为了实现该EBH模型的实验,我们设计了一个基于工程化约瑟夫森结阵列的可扩展circuit-QED架构。数值模拟证实,该模拟器中的微波光子动力学准确地再现了原始自旋动力学。我们的工作为在高度可控的玻色子环境中研究复杂量子自旋动力学提供了一种实验上可行的方法。

英文摘要

We propose and validate a framework for analog simulation of the Heisenberg spin model using a circuit quantum electrodynamics (circuit-QED) platform. To this end, we develop a continuous family of deformed boson representations of the SU(2) algebra, which includes the Holstein-Primakoff and Dyson-Maleev transformations as special cases. For spin-1/2 systems, we introduce a procedure to circumvent the inherent non-Hermiticity of the representation, showing that this entire family yields the extended Bose-Hubbard (EBH) Hamiltonian. For the experimental realization of this EBH model, we design a scalable circuit-QED architecture based on an engineered Josephson junction array. Numerical simulations confirm that the microwave photon dynamics in this simulator accurately reproduces the original spin dynamics. Our work establishes an experimentally accessible method for investigating complex quantum spin dynamics in a highly controllable bosonic setting.

2601.05965 2026-06-03 econ.TH cs.GT math.CO

Game connectivity and adaptive dynamics in many-action games

多动作博弈中的博弈连通性与自适应动力学

Tom Johnston, Michael Savery, Alex Scott, Bassel Tarbush

AI总结 研究多动作博弈中连通性的典型结构,发现当动作数k很大时,连通博弈的比例趋于1-ζ_n,其中ζ_n>0为显式常数,且对于n≥3,ζ_n很小并随n迅速趋于0。

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AI中文摘要

我们根据博弈的连通性性质研究其典型结构。如果一个博弈存在纯纳什均衡,并且从每个非纯纳什均衡的动作组合到每个纯纳什均衡都存在一条最优反应路径,则该博弈是“连通的”;如果一个博弈没有无差异情况,则它是“一般的”。在之前的工作中,我们证明了在所有存在纯纳什均衡的$n$玩家$k$动作一般博弈中,当$n$相对于$k$足够大时,连通博弈的比例趋于$1$。这里,我们考虑$k$很大的情况,其行为不同:我们证明当$k$很大时,连通比例趋于$1-ζ_n$,其中$ζ_n>0$是一个显式常数。因此,恒定比例的多动作博弈是\emph{不}连通的。然而,对于$n\geq3$,$ζ_n$很小且随$n$迅速趋于$0$,因此随着$n$增加,除了极小一部分外,几乎所有多玩家多动作博弈都是连通的。由于连通性有利于均衡收敛,我们找到一个简单的自适应动力学,它保证在几乎所有存在纯纳什均衡的一般博弈中收敛到纯纳什均衡。我们依靠新的概率和组合论证来处理$k$很大的情况。

英文摘要

We study the typical structure of games in terms of their connectivity properties. A game is `connected' if it has a pure Nash equilibrium and there is a best-response path from every action profile which is not a pure Nash equilibrium to every pure Nash equilibrium; a game is generic if it has no indifferences. In previous work we showed that, among all $n$-player $k$-action generic games that admit a pure Nash equilibrium, the fraction that are connected tends to $1$ as $n$ gets sufficiently large relative to $k$. Here, we consider the large-$k$ regime, which behaves differently: we show that the connected fraction tends to $1-ζ_n$ as $k$ gets large, where $ζ_n>0$ is an explicit constant. Thus, a constant fraction of many-action games are \emph{not} connected. However, for $n\geq3$, $ζ_n$ is small and tends to $0$ rapidly with $n$, so as $n$ increases all but a vanishingly small fraction of many-player-many-action games are connected. Since connectedness is conducive to equilibrium convergence, we find a simple adaptive dynamic that is guaranteed to converge to a pure Nash equilibrium in all but a vanishingly small fraction of generic games that have one. We rely on new probabilistic and combinatorial arguments to tackle the large-$k$ regime.

2601.05962 2026-06-03 cond-mat.mes-hall cond-mat.mtrl-sci

Evolution of the Berry curvature dipole in uniaxially strained bilayer graphene

单轴应变双层石墨烯中贝里曲率偶极子的演化

Karel Cuypers, Robin Smeyers, Bert Jorissen, Lucian Covaci

AI总结 通过紧束缚模型研究单轴应变下双层石墨烯中贝里曲率偶极子的演化,发现其对参数化选择高度敏感,且面外压缩通过展宽狄拉克锥增强响应。

Journal ref SciPost Phys. Core 9, 031 (2026)

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AI中文摘要

虽然在原始双层石墨烯中,贝里曲率偶极子(BCD)——非线性反常霍尔效应的必要因素——为零,但单轴应变可以产生有限的BCD。我们通过基于Slater-Koster参数化的紧束缚(TB)方法研究这一点,以捕捉连续模型常常忽略的晶格变形效应。我们证明,BCD随应变和掺杂的演化对参数化选择高度敏感,特别是当包含更长程的层间倾斜跳跃时。此外,面外压缩通过展宽狄拉克锥增强了响应。这些发现为低能连续模型提供了基准,并强调了准确预测双层石墨烯中应变工程霍尔效应需要现实的紧束缚模型。

英文摘要

While in pristine bilayer graphene the Berry curvature dipole (BCD), a necessary ingredient for the nonlinear anomalous Hall effect, is zero, uniaxial strain can give rise to finite BCD. We investigate this by using a tight-binding (TB) approach build on the Slater-Koster parameterization to capture lattice deformation effects often missed by continuum models. We demonstrate that the BCD's evolution with strain and doping is highly sensitive to the choice in parameterization, particularly when including the longer range interlayer skew hoppings. Additionally, out-of-plane compression enhances the response by broadening the Dirac cones. These findings benchmark low-energy continuum models and highlight the necessity of realistic tight-binding models for accurately predicting strain-engineered Hall effects in bilayer graphene.

2601.04892 2026-06-03 gr-qc

Dynamical system approach to the spectral (in)stability of black holes under localised potential perturbations

局域势扰动下黑洞谱(不)稳定性的动力系统方法

T. Torres, S. R. Dolan

AI总结 本文利用动力系统方法研究局域δ函数势扰动对球对称黑洞共振谱的影响,发现谱随扰动参数平滑变形,但弱扰动下存在非线性不稳定性。

Comments 21 pages, 9 figures

Journal ref Phys. Rev. D 113, 104075 - Published 29 May, 2026

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AI中文摘要

本文旨在提高对黑洞附近致密天体或吸积盘等扰动引起的共振谱的理解。已知在径向势中添加弱扰动会强烈破坏黑洞时空的准正则模和Regge极点谱。本文研究(弱或强)局域δ函数扰动对球对称系统共振谱的影响,以解决线性和非线性谱稳定性的基本问题。我们考察了两种情况:具有Pöschl-Teller势的Nariai时空和Schwarzschild时空。结果表明,在两种情况下,随着扰动位置和强度的变化,谱以平滑连续的方式变形。随着扰动强度增加,共振在复平面上沿轨迹迁移,最终趋向于由硬壁情形确定的吸引点。然而,对于弱扰动,未扰动共振附近的轨迹通常受到一组排斥点的强烈影响,这些排斥点对于远离系统的扰动非常接近未扰动共振;因此出现了非线性不稳定性(即线性化近似的失效)。从动力系统角度,吸引和排斥谱点集随着扰动位置的变化而沿自身轨迹运动,这些轨迹被追踪和理解。

英文摘要

The aim of this work is to improve understanding of the resonant spectra of black holes under perturbations arising from e.g. compact objects or accretion disks in their vicinity. It is known that adding a weak perturbation to the radial potential can strongly disrupt the spectrum of quasinormal modes and Regge poles of a black hole spacetime. Here we examine the effect of (weak or strong) localised delta-function perturbations on the resonant spectra of spherically-symmetric systems, to address fundamental questions around linear and non-linear spectral stability. We examine two cases: the Nariai spacetime with a Poschl-Teller potential and the Schwarzschild spacetime. We show that, in either case, the spectrum deforms in a smooth and continuous manner as the position and strength of the perturbation is varied. As the strength of the perturbation is increased, resonances migrate along trajectories in the complex plane which ultimately tend towards attracting points determined by a hard-wall scenario. However, for weak perturbations the trajectory near the unperturbed resonance is typically strongly influenced by a set of repelling points which, for perturbations far from the system, lie very close to the unperturbed resonances; hence there arises a non-linear instability (i.e. the failure of a linearised approximation). Taking a dynamical systems perspective, the sets of attracting and repelling spectral points follow their own trajectories as the position of the perturbation is varied, and these are tracked and understood.

2601.04872 2026-06-03 math.AC

On algebraically maximal valued fields that are not defectless

关于非无缺陷的代数极大值域

Franz-Viktor Kuhlmann

AI总结 本文利用F. Delon的示例和作者之前论文中的技巧,构造了特征为p和0的代数极大值域,这些值域具有缺陷为p的p^2次可分扩张,且秩为2,并探讨了秩为1的类似例子是否存在。

Comments To appear in the Proceedings of the ddg40 conference (Banyuls-sur-mer, 2025), to be published in the "Séminaires et Congrès" of the Société mathématique de France

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AI中文摘要

F. Delon最初给出的一个例子表明,存在一个特征为$p>0$的代数极大离散值域,它允许次数为$p^2$的纯不可分扩张,且缺陷为$p$。这些扩张不是由单个元素生成的。利用作者早期论文中引入的一个技巧,我们构造了特征为$p$以及特征为$0$的代数极大值域,它们允许次数为$p^2$且缺陷为$p$的可分扩张。这些值域的秩为2,而是否存在秩为1的此类例子仍是一个未解决的问题。

英文摘要

An example originally given by F.~Delon shows the existence of an algebraically maximal discretely valued field of characteristic $p>0$ which admits purely inseparable extensions of degree $p^2$ with defect $p$. These extensions are not generated by a single element. Using a trick introduced in an earlier paper of the author, we construct algebraically maximal valued fields, of characteristic $p$ as well as of characteristic $0$, which admit separable extensions of degree $p^2$ with defect $p$. They are of rank 2 and it is an open question whether such examples having rank 1 exist.

2508.16784 2026-06-03 quant-ph

Improving Quantum Recurrent Neural Networks with Amplitude Encoding

改进基于振幅编码的量子循环神经网络

Jack Morgan, Hamed Mohammadbagherpoor, Eric Ghysels

AI总结 本文通过引入近似振幅编码方法EnQode、预处理技术和新型电路架构,改进了基于振幅编码的量子循环神经网络,在保持模型等效性的同时显著降低电路深度,并在两个真实数据集上提升了泛化性能。

Comments 10 pages, 10 Figures

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AI中文摘要

量子机器学习有望推动时间序列预测的发展。受经典RNN启发,量子循环神经网络(QRNN)将时间数据编码为量子态,并周期性地输入量子电路。先前的QRNN工作主要使用角度编码,而振幅编码等替代策略由于计算复杂度高而未被充分探索。本文利用最近提出的近似振幅编码方法EnQode,评估并改进了基于振幅的QRNN。我们提出了一种简单的预处理技术,将振幅编码输入与其归一化前的幅度相结合,从而在两个真实数据集上改善了泛化能力。此外,我们引入了一种新的QRNN电路架构,该架构在数学上等价于原始模型,但实现了电路深度的显著降低。这些贡献共同展示了在模型性能和量子资源效率方面对QRNN设计的实际改进。

英文摘要

Quantum machine learning holds promise for advancing time series forecasting. The Quantum Recurrent Neural Network (QRNN), inspired by classical RNNs, encodes temporal data into quantum states that are periodically input into a quantum circuit. While prior QRNN work has predominantly used angle encoding, alternative encoding strategies like amplitude encoding remain underexplored due to their high computational complexity. In this paper, we evaluate and improve amplitude-based QRNNs using EnQode, a recently introduced method for approximate amplitude encoding. We propose a simple pre-processing technique that augments amplitude encoded inputs with their pre-normalized magnitudes, leading to improved generalization on two real world data sets. Additionally, we introduce a novel circuit architecture for the QRNN that is mathematically equivalent to the original model but achieves a substantial reduction in circuit depth. Together, these contributions demonstrate practical improvements to QRNN design in both model performance and quantum resource efficiency.

2601.04175 2026-06-03 cs.CY

Legal Alignment for Safe and Ethical AI

安全与伦理人工智能的法律对齐

Noam Kolt, Nicholas Caputo, Jack Boeglin, Cullen O'Keefe, Rishi Bommasani, Stephen Casper, Mariano-Florentino Cuéllar, Noah Feldman, Iason Gabriel, Gillian K. Hadfield, Lewis Hammond, Peter Henderson, Atoosa Kasirzadeh, Seth Lazar, Anka Reuel, Kevin L. Wei, Jonathan Zittrain

AI总结 本文通过调查法律对齐的新兴领域,提出三种核心研究路径(合规、解释方法、概念蓝图),以利用法律规则、原则和方法解决AI对齐问题,确保AI系统安全且合乎伦理地运行。

Comments Published in TMLR

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AI中文摘要

人工智能的对齐包括规范性问题(指定AI系统应如何行动)和技术问题(确保AI系统符合这些规范)。迄今为止,AI对齐通常忽视了一个重要的知识和实践来源:法律。在本文中,我们调查了旨在填补这一空白的新兴法律对齐领域,并系统化了研究如何利用法律规则、原则和方法来解决对齐问题,并指导设计安全且合乎伦理的AI系统。我们的调查提供了法律对齐的三个核心研究路径的分类,并探讨了每个路径如何在实践中操作化:(1)设计AI系统以遵守通过合法机构和流程制定的法律规则内容;(2)借鉴法律解释的方法来指导AI系统推理和决策;(3)利用法律概念作为结构蓝图,以应对AI系统中的可靠性、信任和合作挑战。这些研究路径提出了新的概念、实证和制度问题,包括检查特定AI系统应遵循的具体法律,创建评估以评估其在现实世界中的法律合规性,以及开发治理框架以支持法律对齐在实践中的实施。解决这些问题需要法律、计算机科学和其他学科的专业知识,为这些社区提供合作设计更好AI的机会。

英文摘要

Alignment of artificial intelligence (AI) encompasses the normative problem of specifying how AI systems should act and the technical problem of ensuring AI systems comply with those specifications. To date, AI alignment has generally overlooked an important source of knowledge and practice for grappling with these problems: law. In this paper, we survey the emerging field of legal alignment that aims to fill this gap and systematize research that studies how legal rules, principles, and methods can be leveraged to address problems of alignment and inform the design of AI systems that operate safely and ethically. Our survey provides a taxonomy of the three core research pathways of legal alignment and explores how each can be operationalized in practice: (1) designing AI systems to comply with the content of legal rules developed through legitimate institutions and processes, (2) adapting methods from legal interpretation to guide how AI systems reason and make decisions, and (3) harnessing legal concepts as a structural blueprint for confronting challenges of reliability, trust, and cooperation in AI systems. These research pathways present new conceptual, empirical, and institutional questions, which include examining the specific set of laws that particular AI systems should follow, creating evaluations to assess their legal compliance in real-world settings, and developing governance frameworks to support the implementation of legal alignment in practice. Tackling these questions requires expertise across law, computer science, and other disciplines, offering these communities the opportunity to collaborate in designing AI for the better.

2601.03893 2026-06-03 eess.SY cs.SY

Smooth Sampling-Based Model Predictive Control Using Deterministic Samples

基于确定性采样的平滑采样模型预测控制

Markus Walker, Marcel Reith-Braun, Tai Hoang, Gerhard Neumann, Uwe D. Hanebeck

AI总结 针对采样模型预测控制因随机采样导致控制输入不平滑的问题,提出结合确定性采样与交叉熵方法的dsMPPI算法,实现更平滑的轨迹。

Comments To be published in the Proceedings of the 23rd IFAC World Congress (IFAC 2026)

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AI中文摘要

基于采样的模型预测控制(MPC)对非线性系统有效,但由于随机采样,通常会产生不平滑的控制输入。为了解决这个问题,我们扩展了模型预测路径积分(MPPI)框架,采用确定性采样和来自交叉熵方法(CEM)--MPC的改进,如迭代优化,提出了确定性采样MPPI(dsMPPI)。这种组合利用了MPPI的指数加权以及确定性样本的效率。实验表明,与最先进的方法相比,dsMPPI实现了更平滑的轨迹。

英文摘要

Sampling-based model predictive control (MPC) is effective for nonlinear systems but often produces non-smooth control inputs due to random sampling. To address this issue, we extend the model predictive path integral (MPPI) framework with deterministic sampling and improvements from cross-entropy method (CEM)--MPC, such as iterative optimization, proposing deterministic sampling MPPI (dsMPPI). This combination leverages the exponential weighting of MPPI alongside the efficiency of deterministic samples. Experiments demonstrate that dsMPPI achieves smoother trajectories compared to state-of-the-art methods.

2601.02876 2026-06-03 math.AP math.FA

The W-Operator: A Volterra Fractional Time Operator with Sharp Bernstein Threshold and Regularized Memory

W-算子:具有尖锐Bernstein阈值和正则化记忆的Volterra分数阶时间算子

Mohamed Wakrim

AI总结 提出一种具有Volterra结构的新分数阶时间算子W-算子,通过符号分析明确其Bernstein函数类隶属的精确阈值,并建立抽象Cauchy问题的适定性与W-预解族理论。

Comments 30 pages, 3 figures. Submitted to Fractional Calculus and Applied Analysis (FCAA)

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AI中文摘要

我们引入一种新的具有Volterra结构的两参数分数阶时间算子,记为${}^{W}D_{t}^{α,β}$,通过Laplace符号定义为\[ Φ_{α,β}(s) = \frac{s^α}{\bigl(1+(1-α)s^{α-1}\bigr)^β}, \qquad 0<α<1, \ β\ge0. \] 该算子保留了Caputo型高频行为,同时通过$β$允许对低频区域进行受控修改。我们发展了显式的符号/Volterra理论:Prabhakar型核、左逆Volterra积分以及分数阶微积分基本定理。一个核心贡献是对符号的Bernstein结构的精确澄清。我们表明,对于任何$β>0$,自然分解$Φ_{α,β}(s)=s^αh_α(s)^β$不符合经典的Bernstein乘积机制。然而,通过对$Φ'_{α,β}$的直接完全单调性论证,我们证明了精确的Bernstein阈值\[ Φ_{α,β}\in\mathcal{BF} \quad\Longleftrightarrow\quad 0\leβ\le1. \] 其中$\mathcal{BF}$表示Bernstein函数类。对于$β>1$,由于低频渐近凸性障碍,Bernstein性质失效。这表明自然范围$0\leβ\le1$的Bernstein性质是真实的,但并非由标准乘积机制产生。然后,我们通过预解估计和Laplace反演建立了具有扇形生成元的抽象W-分数阶Cauchy问题的适定性,得到了具有时间正则性和光滑性质的W-预解族。作为说明,我们将该理论应用于W-分数阶扩散模型,并讨论了$β$对谱模式弛豫的影响。

英文摘要

We introduce a new two-parameter fractional time operator with Volterra structure, denoted by ${}^{W}D_{t}^{α,β}$, defined through the Laplace symbol \[ Φ_{α,β}(s) = \frac{s^α}{\bigl(1+(1-α)s^{α-1}\bigr)^β}, \qquad 0<α<1, \ β\ge0. \] The operator preserves the Caputo-type high-frequency behavior while allowing a controlled modification of the low-frequency regime via $β$. We develop an explicit symbolic/Volterra theory: Prabhakar-type kernels, a left-inverse Volterra integral, and a fractional fundamental theorem of calculus. A central contribution is a sharp clarification of the Bernstein structure of the symbol. We show that the natural factorization $Φ_{α,β}(s)=s^αh_α(s)^β$ does not fit the classical Bernstein product mechanism for any $β>0$. Nevertheless, by a direct complete-monotonicity argument on $Φ'_{α,β}$, we prove the exact Bernstein threshold \[ Φ_{α,β}\in\mathcal{BF} \quad\Longleftrightarrow\quad 0\leβ\le1. \] where $\mathcal{BF}$ denotes the class of Bernstein functions \noindent For $β>1$, the Bernstein property fails by a low-frequency asymptotic convexity obstruction. This shows that the Bernstein nature of the natural range $0\leβ\le1$ is genuine but is not produced by the standard product mechanism. We then establish well-posedness of abstract W-fractional Cauchy problems with sectorial generators by resolvent estimates and Laplace inversion, yielding a W-resolvent family with temporal regularity and smoothing properties. As an illustration, we apply the theory to a W-fractional diffusion model and discuss the effect of $β$ on the relaxation of spectral modes.

2504.05129 2026-06-03 cond-mat.mes-hall cond-mat.str-el cond-mat.supr-con

Stripe Order in the Metallic and Superconducting Phases of Rhombohedral Hexalayer Graphene

菱面体六层石墨烯金属相和超导相中的条纹序

Peiyu Qin, Hai-Tian Wu, Ron Q. Nguyen, Erin Morissette, Naiyuan J. Zhang, K. Watanabe, T. Taniguchi, J. I. A. Li

AI总结 本文在菱面体六层石墨烯中观测到电荷条纹序与超导电性和磁性共存,发现超导态继承强各向异性并表现出磁滞转变,揭示了旋转对称性破缺在非常规超导中的作用。

Comments 28 pages with method section and SI, 4 figures in main text

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AI中文摘要

在强关联电子系统中,库仑相互作用经常导致自发打破旋转对称性的涌现电子序。理解这种对称性破缺如何与其他集体现象(如非常规超导电性)交织,以及它如何塑造实验可观测量(特别是输运响应),仍然是现代凝聚态物理的核心挑战。在这里,我们报告了电荷条纹序的实验特征,其输运各向异性可与量子霍尔条纹相媲美,并与菱面体六层石墨烯中的超导电性和磁性共存。引人注目的是,低温超导态不仅继承了强各向异性,而且由于底层条纹序的可调性,表现出广泛的磁滞转变。总之,这些发现揭示了超导电性与电荷条纹之间先前未被认识的共存,为旋转对称性破缺在菱面体石墨烯中塑造非常规超导电性的作用提供了新的见解。

英文摘要

In strongly correlated electronic systems, Coulomb interactions frequently give rise to emergent electronic orders that spontaneously break rotational symmetry. Understanding how such symmetry breaking intertwines with other collective phenomena-such as unconventional superconductivity-and how it shapes experimental observables, particularly transport responses, remains a central challenge in modern condensed-matter physics. Here we report experimental signatures of charge stripe order, with a transport anisotropy rivaling that of quantum Hall stripe phases, coexisting with superconductivity and magnetism in rhombohedral hexalayer graphene. Strikingly, the low-temperature superconducting state not only inherits strong anisotropy but also exhibits a wide range of hysteretic transitions arising from the tunability of the underlying stripe order. Together, these findings reveal a previously unrecognized coexistence between superconductivity and charge stripe, shedding new light on the role of rotational symmetry breaking in shaping unconventional superconductivity in rhombohedral graphene.