arXivDaily arXiv每日学术速递 周一至周五更新
重置
全部学科分类 2081
2605.06547 2026-05-11 cs.IT math.IT quant-ph

Affine Subcode Ensemble Decoding for Degeneracy-Aware Quantum Error Correction

Leo Wursthorn, Jonathan Mandelbaum, Sisi Miao, Hedongliang Liu, Holger Jäkel, Stergios Koutsioumpas, Laurent Schmalen

AI总结 本文研究了量子低密度奇偶校验码在退化问题影响下的纠错性能,提出了一种基于仿射子码集合的解码方法,通过向稳定子码的校验矩阵添加线性无关行,缩小退化解的搜索空间,从而提升解码收敛性。该方法将经典领域的仿射子码集合解码技术扩展到量子领域,并采用过完备矩阵处理每条解码路径,仿真结果表明在环形码和广义自行车码上,逻辑错误率显著降低。

Comments Submitted to IEEE Information Theory Workshop 2026

详情
英文摘要

Quantum low-density parity-check codes are promising candidates for low-overhead fault-tolerant quantum computing, but degeneracy is known to impair the convergence of belief-propagation (BP) decoding of these codes. In this work, we show that appending linearly independent rows to a check matrix of a stabilizer code can reduce the search space for a valid degenerate solution. Motivated by this, we extend the recently proposed affine subcode ensemble decoding technique from the classical to the quantum setting. Moreover, we employ overcomplete matrices for each decoding path. Monte-Carlo simulations on toric and generalized bicycle codes demonstrate improved convergence and reduced logical error rate.

2605.06515 2026-05-11 math.AT

An algebraic model for rational ultracommutative rings

William Balderrama, Jack Morgan Davies, Sil Linskens

AI总结 本文研究了有理超交换环谱的代数模型,提出了一种通过几何固定点构造的几何范数,并证明其与膨胀操作一起构成了从有限群范畴到对称单子范畴的函子。该函子在有理对象的子范畴上诱导出等价,从而为有理全局谱和规范 $G$-交换环谱提供了代数模型。研究的核心在于对几何固定点的自然变换进行精细化,使其与限制和范数操作兼容,并在有理对象上实现等价。

Comments v2: fixed references, 18 pages, comments welcome

详情
英文摘要

Given a global equivariant ultracommutative ring spectrum $E$ and inclusion $H\hookrightarrow G$ of finite groups, one may apply geometric fixed points to the norm $N_H^G E_H \to E_G$ to obtain what we call a \emph{geometric norm} $Φ^H E \to Φ^G E$. We prove that, together with inflations, these assemble into a functor $Φ\colon\mathrm{UCom}_{\mathrm{fin}} \to \mathrm{Fun}(\mathrm{Span}(\mathcal{G},\mathcal{E},\mathcal{O}),\mathrm{CAlg})$, where $\mathrm{Span}(\mathcal{G},\mathcal{E},\mathcal{O})$ is the span category of finite connected groupoids with full backwards maps and faithful forwards maps, and that $Φ$ restricts to an equivalence between full subcategories of rational objects. Central to our construction is a refinement of geometric fixed points to a natural transformation $Φ\colon \mathrm{Sp}_\bullet\to\mathrm{Fun}(\mathrm{Orb}_\bullet^\simeq,\mathrm{Sp})$ which is compatible with restrictions and norms, and which restricts to an equivalence on full subcategories of rational objects. We explain how this may also be used to recover theorems of Barrero--Barthel--Pol--Strickland--Williamson and Wimmer on algebraic models for rational global spectra and normed $G$-commutative ring spectra respectively.

2605.06493 2026-05-11 math.OC

Confidentiality of Linear Control Systems with Quadratic Output Under Sensor Attacks [Extended Version]

Zeyad M. Manaa, Nathan van de Wouw, Michelle S. Chong

AI总结 本文研究了具有二次输出的线性控制系统在传感器攻击下的状态估计问题,特别是在系统在平衡点处局部不可观测的情况下。研究发现,尽管系统本身存在可观测性缺陷,但攻击者通过在测量通道中注入适当信号,可以诱导出可观测性。论文分析了注入信号能否成功诱导可观测性的条件,并在成功情况下设计了一种观测器,使状态估计以局部指数速率收敛到真实状态。仿真结果验证了理论分析的有效性。

Comments This paper has been accepted at the IFAC World Congress 2026

详情
英文摘要

We study the state estimation problem for linear control systems with quadratic outputs which are locally unobservable at the equilibrium. We show that, despite this inherent lack of observability, an adversary with sensor read and write capability can induce observability by injecting an appropriate signal into the measurement channel. Taking the role of an adversary, we characterize when an injected signal can or cannot induce observability and, in the successful case, construct an observer that achieves local exponential convergence of state estimates to the true states of the system. A simulation study demonstrates our results.

2605.06253 2026-05-11 math.CO

On Ramsey goodness of $K_{2,n}$ versus cycles

Abisek Dewan, Sayan Gupta, Rajiv Mishra

AI总结 本文研究了图 $K_{2,n}$ 与环 $C_m$ 之间的 Ramsey 良好性问题。作者证明了在特定条件下,$R(K_{2,n}, C_m) = m+1$,从而确认了 $C_m$ 在该范围内的 $K_{2,n}$-良好性,并改进了 Pokrovskiy 和 Sudakov 的相关结果。此外,作者还构造了一个反例,表明当 $n \geq m+2$ 且 $m$ 为偶数时,$K_{2,n}$ 并不是 $C_m$-良好的。

Comments 16 pages, 3 figures

详情
英文摘要

A graph $G$ is called $H$-good if $R(G,H)=(|G|-1)(χ(H)-1)+σ(H)$, where $σ(H)$ denotes the size of the smallest color class in a $χ(H)$-coloring of $H$. In Ramsey theory, it is an interesting problem to study whether a graph $G$ is $H$-good or not. In this article, we study the Ramsey goodness of the pair $(K_{2,n},C_m)$, which naturally lies between the classical star-cycle and book-cycle problems. We prove that \begin{equation*} R(K_{2,n},C_{\{m,m+1\}})=m+1. \end{equation*} for all $m\ge 2n+1$, and consequently establish that \begin{equation*} R(K_{2,n},C_{m})=m+1. \end{equation*} for all $m\ge 3n+4$. This proves that $C_m$ is $K_{2,n}$-good in this range and improves a particular case of a result on the Ramsey goodness by Pokrovskiy and Sudakov. Further, we provide a construction of a graph that disproves the $C_{m}$-goodness of $K_{2,n}$ for all even $m$ satisfying $n\geq m+2$.

2605.06045 2026-05-11 eess.SY cs.SY

Kirigami-Structured Electronic Capsule for Long-Term Continuous Gastric Monitoring

Hen-Wei Huang, Claas Ehmke, Dawei Wang, Blake Smith, Ziyao Zhou, Rong Tan, David Werder, Crystan McLymore, Niels Neidlein, Emanuele Falli, Ali Imani, James McRae, Yeseul Jeon, So-Yoon Yang, Wesley S. Culberson, James Byrne, Giovanni Traverso

AI总结 该研究提出了一种基于 kirigami 结构的可吞咽电子胶囊,用于实现胃部的长期连续监测。通过结合仿生电控释放机制与 kirigami 电子架构,该胶囊能够在胃内稳定驻留数周,并具备按需拆解功能,解决了传统可吞咽设备在运行时间、机械适应性和无线通信可靠性方面的不足。研究还展示了该系统在胃部辐射监测中的应用,为无创体内监测提供了新的解决方案。

Comments This submission is withdrawn because the author/contributor information in the current version was submitted before explicit confirmation had been obtained from all relevant team members. We are withdrawing the article to avoid an inaccurate or unverified authorship/contribution record

详情
英文摘要

Ingestible electronic systems enable non-invasive, in situ sensing within the gastrointestinal (GI) tract, yet clinical translation has been limited by uncontrolled transit, short operational lifetimes, and unreliable wireless communication that prevent continuous monitoring. Here, we present a gastric-resident ingestible robotic platform that achieves week-long operation through integration of a bioinspired, electrically triggered release mechanism with a kirigami-enabled electronic architecture. A kirigami-patterned flexible printed circuit board spans the capsule body and deployable superelastic arms, enabling high-density integration of sensing, power management, and wireless modules within a constrained volume while tolerating large mechanical deformation during gastric residence. Stable retention and on-demand disassembly are achieved using thermally responsive polycaprolactone joints that transition from rigid to compliant states under electrical activation, avoiding dependence on variable chemical triggers. Reliable telemetry in the highly attenuating gastric environment is maintained using a dual-band Bluetooth Low Energy and sub-gigahertz module with RSSI- and throughput-aware adaptive transmission, balancing link robustness and energy consumption. We demonstrate long-term, continuous monitoring of gastric radiation exposure, enabling early detection of dose accumulation and providing a promising in vivo alternative to wearable or handheld dosimeters. Swine studies confirm stable gastric residence, sustained real-time telemetry, and safe gastrointestinal passage following triggered disassembly. This work establishes kirigami-enabled integration as a scalable strategy for long-term gastric-resident robotic systems.

2605.05976 2026-05-11 eess.SY cs.SY

Community-to-Vehicle: Integrating Electric Vehicles into Energy Communities -- A Swiss Case Study

Na Li, Dong Liu, Stavros Orfanoudakis, Özge Okur, N. K. Panda, Pedro P. Vergara, Binod Koirala

AI总结 本文探讨了如何通过“社区到车辆”(C2V)机制将电动汽车充电整合进本地能源社区,以提高本地可再生能源的利用效率。研究基于瑞士的本地电力社区框架,设计了从完全分离到协调充电的过渡场景,评估了对电动汽车用户和社区的影响。结果表明,C2V机制显著提升了本地光伏的利用率,降低了充电成本,并为社区创造了额外收入,展示了其作为可行的制度设计在现有法规下推动社区与电动汽车协同发展的潜力。

详情
英文摘要

The institutional separation between local energy communities and public electric vehicle (EV) charging limits the efficient use of locally generated renewable energy. This paper introduces the concept of community-to-vehicle (C2V) as an institutional design mechanism to bridge this gap by enabling EV charging within the community boundary, where locally generated photovoltaic (PV) surplus is preferentially allocated and offered to external users at a community charging price. Building on the recently introduced local electricity community framework in Switzerland, we design scenarios that capture the transition from full separation to coordinated EV charging and evaluate their impacts on EV users and the community. The results show that C2V significantly improves local PV utilization and enhances economic performance, reducing EV charging costs relative to commercial alternatives while generating additional revenue streams for the community. These findings highlight the potential of C2V as a practical, implementable mechanism for integrating EV charging into local energy communities, providing a clear pathway for adopting coordinated community-EV interaction within existing regulatory frameworks.

2605.05484 2026-05-11 math.DS math.NT

Multifractal analysis of power means for the Schneider map on $p\mathbb{Z}_p$

Matias Alvarado, Nicolás Arévalo-Hurtado

AI总结 本文研究了施耐德连续分数映射在 $p\mathbb{Z}_p$ 上的幂平均系数的渐进行为,利用热力学形式主义的工具,计算了相应水平集的豪斯多夫维数,并得到了相关的多重分形谱的显式公式。由于几何势函数的局部常数性质,使得该问题能够以对数函数的形式进行精确描述,这与经典的实数情形形成鲜明对比。

Comments Comments are welcome

详情
英文摘要

We study the asymptotic power means of the coefficients associated with the Schneider continued fraction map on $p\mathbb{Z}_p$. Using tools from thermodynamic formalism, we compute the Hausdorff dimension of the corresponding level sets and obtain explicit formulas for the associated multifractal spectra. The locally constant nature of the geometric potential enables a precise description in terms of polylogarithm functions, in sharp contrast with the classical real setting.

2605.05210 2026-05-11 cs.IR

DisastRAG: A Multi-Source Disaster Information Integration and Access System Based on Retrieval-Augmented Large Language Models

Bo Li, Zhitong Chen, Kai Yin, Junwei Ma, Yiming Xiao, Ali Mostafavi

AI总结 DisastRAG 是一个基于检索增强大语言模型的多源灾难信息集成与访问系统,旨在解决现有系统在处理异构、时效性强和依赖上下文的灾难信息时的不足。该系统采用多路径架构,整合了结构化数据检索、非结构化文档检索和外部网络信息访问,提升了信息获取的全面性与灵活性。实验表明,检索增强显著提升了模型在多项选择和开放性问题上的表现,且不同模型对检索结果的敏感度存在差异,验证了系统在实际灾难管理场景中的有效性与扩展性。

详情
英文摘要

Effective disaster management requires rapid access to information distributed across structured operational records, unstructured institutional documents, and dynamic external sources. However, most existing disaster information systems and retrieval-augmented generation frameworks remain organized around a single access pathway, limiting their ability to support heterogeneous, time-sensitive, and context-dependent information needs. This study presents DisastRAG, a disaster-aware information integration and access system that combines large language models with retrieval-augmented access to structured, unstructured, and contextual disaster information. The framework is built around a multi-path architecture that supports document retrieval over a curated hazard corpus, structured access over relational disaster records, and external web fallback for out-of-corpus requests, while also incorporating query understanding, strategy routing, response generation, and contextual memory within a unified system. We evaluated the document retrieval performance using four open-source large language models across multiple retrieval configurations on multiple-choice and open-ended disaster information tasks. Retrieval augmentation consistently improves performance over no-retrieval baselines, yielding multiple-choice gains of 12-23 percentage points and open-ended keypoint coverage gains of up to 10.5 percentage points. Results show that larger candidate pools are most helpful for weaker models, while stronger models are more sensitive to retrieval noise. Hybrid retrieval performs best for open-ended coverage, whereas vector retrieval and shallower reranking more often favor closed-form factual selection. Case studies further show that structured access and web fallback extend the framework beyond document-only RAG.

2605.05194 2026-05-11 cond-mat.stat-mech

Singular Behavior of Observables at Hopf Bifurcations

Benedikt Remlein, Massimiliano Esposito

AI总结 该论文研究了在霍普夫分岔点附近时间平均可观测量的奇异行为。尽管系统在分岔点处不存在奇异的稳态,但作者发现时间平均可观测量在振荡出现时会表现出奇异性。其根源在于几何相平均过程消除了振荡幅值的奇次幂,而幅值平方则随分岔距离平滑变化,从而导致可观测量的非解析行为。研究揭示了霍普夫分岔作为非解析可观测量行为的普遍机制,并在多种振荡系统中验证了这一现象。

Comments improved presentation

详情
英文摘要

Hopf bifurcations are a universal route to self-sustained oscillations in driven systems. Despite the absence of any singular stationary state, we show that time-averaged observables generically exhibit singularities at the onset of oscillations. The origin of this behavior is geometric: phase averaging over the emergent periodic attractor eliminates odd powers of the oscillation amplitude, while the squared amplitude varies smoothly with the distance from the bifurcation. Consequently, the excess of any smooth time-averaged observable admits an integer-power expansion; observables remain finite but display discontinuities in finite-order derivatives. This yields an Ehrenfest-like hierarchy of Hopf singularities, in which the first nonanalytic derivative is determined by the lowest-order coupling between the observable and the limit-cycle waveform that survives phase averaging. Generic observables therefore exhibit kink singularities, while symmetry or geometric cancellations can suppress lower-order couplings and shift nonanalyticity to higher derivatives. We demonstrate this mechanism in chemical, electronic, and climate oscillators. Our results identify supercritical Hopf bifurcations as a universal mechanism for nonanalytic observable behavior, where singular features arise without any underlying singular stationary state. They thus provide a generic setting for singular behavior without divergence.

2605.05099 2026-05-11 stat.AP cs.MS

Randompack: Cross-Platform Reproducible Random Number Generation and Distribution Sampling

Kristján Jónasson

AI总结 本文介绍了一个名为 Randompack 的 C 语言随机数生成库,支持多种现代随机数生成算法和多种连续分布采样方法,并实现了跨平台的可重复性,即在不同编程语言、硬件和编译器下使用相同种子可获得一致结果。该库结构清晰,将随机数引擎与分布层分离,便于灵活组合使用,同时在性能上优于其他同类库,且提供了全面的并行模拟支持和多种语言接口。

Comments 19 pages

详情
英文摘要

A C library for random number generation, Randompack, is presented. The library implements several modern random number generators (engines), including xoshiro256, PCG64, Philox, ranlux++, and sfc64; 14 continuous distributions including uniform, normal, exponential, gamma, beta, and multivariate normal; raw bit streams, bounded integers, permutations, and sampling without replacement. The engine and the distribution layers are separated so any engine can be used with any distribution. Benchmarks show that Randompack is faster overall than competing libraries, with speedup factors ranging from about 1 to 15 depending on engine, distribution, interface, and platform. A distinguishing feature is reproducibility: with the same seeds Randompack gives compatible results across programming languages, computers, CPU architectures, and compilers. The library includes comprehensive support for parallel simulation. It is accompanied by a comprehensive test suite, benchmarking programs, and example programs. Interfaces to Fortran, Python, Julia, and R have been implemented; their benchmark results are included, although their design and implementation are otherwise outside the scope of the article. Unlike other available C libraries with comparable scope, Randompack is permissively licensed under the MIT license, and it is open source and publicly available through GitHub and conda-forge.

2605.04746 2026-05-11 math.OC

Distributed Energy System Design including Unbalanced AC Power Flow for Large LV Networks with ADMM

Robert Steven, Oleksiy V. Klymenko, Michael Short

AI总结 本文研究了在低压配电网中包含大量分布式能源资源(DERs)时,如何进行分布式能源系统(DES)的选址、定容与调度,以满足电力和热负荷需求。为解决非凸混合整数非线性规划(MINLP)模型在大规模网络中求解效率低的问题,作者提出了一种分步求解策略,并结合混合整数线性规划(MILP)、非线性规划(NLP)及互补性改革方法,最终采用ADMM分布式优化方法加速求解。实验结果表明,该方法在欧洲低压测试馈线数据集上实现了最高13倍的加速效果,且优化间隙保持在0.61%以内。

Comments 54 pages, 26 figures

详情
英文摘要

With the addition of large numbers of distributed energy resources (DERs) to distribution networks comes the increasing risk that their operation may violate the safety constraints of these networks. The problem considered in this paper is that of combined siting, sizing and dispatch of these DERs, also known as distributed energy system (DES) design, to help meet electrical and heat loads within the network. Here, the operation of these DERs is modelled, along with the unbalanced three-phase alternating current (AC) power flow in the network. When this network power flow is considered, this admits a non-convex mixed-integer nonlinear program (MINLP) model formulation which scales poorly with network size in terms of solve time. To address this, the problem is decomposed into a series of algorithmic steps, starting with a mixed-integer linear program (MILP) formulation that does not consider network constraints, then fixing binary variables, adding power flow constraints and solving as a nonlinear program (NLP) and finally removing operational binary variables and replacing them with a complementarity reformulation. As the main contributors to the overall solve time, the NLP and Complementarity steps are solved using a hybrid spatial/temporal decomposition strategy and the alternating direction method of multipliers (ADMM) distributed optimisation method. Results are presented for networks based on the European low voltage test feeder with up to 55 loads and 120 timepoints, with the ADMM approach showing speed-ups of up to 13x when considering parallel computation of the subproblems, for a maximum observed optimality gap of 0.61%.

2605.04674 2026-05-11 physics.ins-det nucl-ex

Machine learning inference of fission yields from gamma spectroscopy for very low-yield nuclear test verification

Julien de Troullioud de Lanversin, Jiehui Li, Christopher Fichtlscherer, Dongdong She, Moritz Kütt

AI总结 该研究针对全面禁止核试验条约(CTBT)中零产量标准下的非常低产量核试验验证难题,提出了一种基于机器学习的伽马谱分析方法,用于推断核试验的裂变产量。研究通过高保真三维蒙特卡洛粒子输运模拟生成了6600万种场景下的伽马谱数据,并从中提取特征训练模型,实现了对试验是否超过设定产量阈值的二分类判断以及对实际产量的回归估计。实验表明,该方法在政策相关产量范围内具有高精度,为建立可靠的零产量标准验证协议提供了技术支撑。

详情
英文摘要

Very low-yield nuclear tests pose a major verification challenge for the zero-yield standard of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The zero-yield standard prohibits any explosive experiment that produces a self-sustaining fission chain reaction while allowing subcritical experiments. Previous research shows that on-site gamma spectroscopy of post-test debris provides useful insight into the criticality level, although it remains heavily dependent on knowledge of certain experimental settings. Here, we adopt a new approach whereby machine learning models are trained on simulated gamma spectroscopy data to infer the fission yield of a nuclear very low-yield test. Using high-fidelity 3D Monte Carlo particle transport simulations, we generated gamma spectra measured outside containment vessels after very low-yield tests for 66 million representative scenarios. From these spectra, we extracted 82 fission-product-to-plutonium-239 peak ratios, then trained ML models for two tasks: (1) binary classification of whether a test exceeded a chosen yield threshold, and (2) regression to estimate the actual yield. We find that XGBoost performs best on the classification task across the most policy-relevant yield range. The classifier achieves high accuracy even for yields near the chosen threshold (e.g., >95% for yields +-100 g around a threshold at 1 kg TNT), and the regressor presents a mean absolute relative error of 12.4% for measurements taken a month to a year after the test. These results demonstrate that using machine learning to infer the yield of a past very low-yield nuclear test from gamma spectroscopy data is feasible and accurate. This approach can support efforts to establish a robust verification protocol for the zero-yield standard and could pave the way for a future yield threshold-based verification regime that is both technically feasible and politically viable.

2605.03828 2026-05-11 math.LO

A Topological Rainbow Ramsey Theorem

Hannes Jakob, Jing Zhang

AI总结 本文研究了拓扑彩虹 Ramsey 理论中的一个一致性问题,证明了在适当大基数存在的前提下,对于任意的可数到一染色 $c: [ω_2]^2\to ω_2$,都存在一个闭子集 $A\subseteq ω_2$,其序型为 $ω_1$,使得 $c$ 限制在 $[A]^2$ 上是单射的。该结果同时强化了 Abraham、Cummings 和 Smyth 以及 Garti 和 Zhang 的两个定理,并回答了 Garti 和 Zhang 提出的一个问题。文中还引入了一些新的组合原理,包括可数初等子模型塔、回归函数相关的博弈以及强 Chang 猜想的变体,这些是证明中的关键工具。

Comments 33 Pages, comments are welcome!

详情
英文摘要

We show that it is consistent relative to the existence of suitable large cardinals that for any countable-to-one coloring $c: [ω_2]^2\to ω_2$, there exists a closed subset $A\subseteq ω_2$ of order type $ω_1$ such that $c\restriction [A]^2$ is injective. This theorem simultaneously strengthens two theorems, one by Abraham, Cummings and Smyth and another one by Garti and Zhang, as well as answers a question raised by Garti and Zhang. New combinatorial principles involving towers of countable elementary submodels, games concerning regressive functions and variants of strong Chang's conjecture, which are key elements of the proof, are investigated.

2605.03811 2026-05-11 eess.SY cs.SY

A Directivity-Dependent Rician K-Factor Model for Indoor Industrial Channels

Dimitrios C. Tzarouchis

AI总结 本文提出了一种基于物理原理的闭合形式模型,用于描述室内工业环境中天线方向性与均方根时延扩展、平均过冲时延之间的关系。研究从瑞利K因子出发,揭示了K因子与总发射加接收天线增益之间的依赖关系,并通过一个表征散射各向异性的因子进行关联。该模型适用于任意散射功率时延分布,并通过75 GHz频段下的射线追踪仿真验证了其有效性,为宽带毫米波工业通信链路的天线设计提供了理论依据和实用规则。

Comments unresolved results issue/ re-framing required

详情
英文摘要

We derive a physics-based, closed-form model linking antenna directivity to the root-mean-square (RMS) delay spread and mean excess delay in large reverberant indoor environments. Starting from the Rician K-factor-the ratio of line-of-sight (LOS) to scattered power we show that K scales with the total transmit-plus-receive (Tx+Rx) antenna gain through a single reverberance factor that quantifies scatter anisotropy. For an arbitrary scatter power delay profile (PDP), we derive a general identity connecting sigma, tau, and K; the exponential scatter model is the physically motivated special case. Ray-tracing simulations over 100 random link placements in a 57300 m3 industrial hall at 75 GHz validate the model. Compact design rules map target delay-spread values to the minimum required antenna gain, enabling wideband mmWave industrial links.

2605.03651 2026-05-11 math.DG

Minimal Submanifolds of The Complex and Quaternionic Projective and Hyperbolic Spaces $\cn P^{2n-1}$, $\hn P^{n-1}$, $\cn H^{2n-1}$, $\hn H^{n-1}$ via Harmonic Morphisms

Sigmundur Gudmundsson

AI总结 本文研究了复射影空间和复双曲空间中非全纯的、完备的、极小子流形的构造,并进一步给出了四元数射影空间和四元数双曲空间中完备极小子流形的构造,所有构造的子流形均为码维为二的嵌入。研究主要利用了从这些空间出发的复值调和映射作为核心工具,为极小子流形的构造提供了新的方法和视角。

详情
英文摘要

In this work we construct non-holomorphic, complete and minimal submanifolds of the odd-dimensional complex projective spaces $\cn P^{2n-1}$ and their dual complex hyperbolic spaces $\cn H^{2n-1}$. We then provide complete minimal submanifolds of the quaternionic projective spaces $\hn P^{n-1}$ and their dual quaternionic hyperbolic spaces $\hn H^{n-1}$. All the constructed minimal submanifolds are of codimension two. Our main tools are complex-valued harmonic morphisms from the above mentioned ambient spaces.

2605.03206 2026-05-11 math.PR

The maximum-entropy median-martingale

Rikhav Shah, Vilas Winstein

AI总结 本文研究了在单位区间上满足中位数鞅性质的最大熵随机游走,即其下一状态的中位数等于当前状态。该游走的平稳分布为反正弦分布,并给出了与布朗运动两类经典反正弦定律的联系的证明。文章进一步推广了鞅的概念,探讨了更广义的随机游走类并进行了相应的刻画。

详情
英文摘要

This short note explores the maximum-entropy walk on the unit interval that is a median-martingale. That is, the median of its next state is equal to its current state. The stationary distribution of this walk is the arcsine distribution, and we provide a proof that elucidates the connection to two classical arcsine laws for Brownian motion. The notion of a martingale is further generalized, and a larger class of walks is considered and similarly characterized.

2605.03169 2026-05-11 q-bio.NC

NeuralSet: A High-Performing Python Package for Neuro-AI

Jean-Rémi King, Corentin Bel, Linnea Evanson, Julien Gadonneix, Sophia Houhamdi, Jarod Lévy, Josephine Raugel, Andrea Santos Revilla, Mingfang Zhang, Julie Bonnaire, Charlotte Caucheteux, Alexandre Défossez, Théo Desbordes, Pablo Diego-Simón, Shubh Khanna, Juliette Millet, Pierre Orhan, Saarang Panchavati, Antoine Ratouchniak, Alexis Thual, Teon L. Brooks, Katelyn Begany, Yohann Benchetrit, Marlène Careil, Hubert Banville, Stéphane d'Ascoli, Simon Dahan, Jérémy Rapin

AI总结 本文介绍了NeuralSet,一个高效的Python工具包,旨在解决神经科学与现代人工智能融合中的软件生态碎片化问题。该框架统一处理多种神经记录数据(如fMRI、EEG和 spikes)及复杂实验刺激(如文本、音频和视频),通过解耦元数据与高效的数据提取,实现了与预训练深度学习模型的无缝集成。NeuralSet 提供了一个统一的PyTorch接口,支持从本地开发到高性能集群的无缝扩展,为下一代神经-人工智能研究提供了可扩展的基础设施。

详情
英文摘要

Artificial intelligence (AI) is increasingly central to understanding how the brain processes information. However, the integration of neuroscience and modern AI is bottlenecked by a fragmented software ecosystem. Current tools are siloed by recording modality and optimized for small-scale, in-memory workflows, limiting the use of massive, naturalistic datasets. Here, we introduce NeuralSet, a Python framework that efficiently unifies the processing of diverse neural recordings (including fMRI, M/EEG, and spikes) and complex experimental stimuli (such as text, audio, and video). By decoupling experimental metadata from lazy, memory-efficient data extraction, NeuralSet harmonizes standard neuroscientific preprocessing pipelines with pretrained deep learning embeddings. This approach provides a single PyTorch-ready interface that scales seamlessly from local prototyping to high-performance cluster execution. By eliminating manual data wrangling and ensuring full computational provenance, NeuralSet establishes a scalable, unified infrastructure for the next generation of neuro-AI research.

2605.02518 2026-05-11 math.NT

Expansion in $\text{SL}_2(\mathbb Z/q\mathbb Z)$ and Zaremba's conjecture

Xin Zhang

AI总结 本文建立了模 $q$ 整数矩阵群 $\text{SL}_2(\mathbb Z/q\mathbb Z)$ 的展开理论,并将其应用于近期由 Shkredov 提出的框架中,从而验证了 Zaremba 猜想。研究通过分析该群的结构与展开性质,为数论中的重要问题提供了新的证明方法。

Comments Typos in v1 corrected

详情
英文摘要

We establish an expansion theory for $\text{SL}_2(\mathbb Z/q\mathbb Z)$. Incorporating this into a framework recently developed by Shkredov, we confirm Zaremba's conjecture.

2605.02397 2026-05-11 cond-mat.quant-gas cond-mat.mes-hall physics.optics

Dynamical universality in a driven quantum fluid of light

Ivan Gnusov, Paolo Comaron, Antonio Gianfrate, Dimitrios Trypogeorgos, Marzena Szymanska, Paolo Cazzato, Milena De Giorgi, Daniele Sanvitto, Dario Ballarini

AI总结 该研究探讨了在驱动的量子光流体中动态普适性的表现,通过研究半导体微腔中激子-极化子构成的系统,揭示了临界行为下的普适标度关系。研究测量了凝聚阈值以下无序相中关联长度和弛豫时间的增长关系,发现其满足 $τ \propto ξ^z$ 的普适规律,其中动态指数 $z \approx 2$,表明非守恒序参量的扩散动力学。该成果将临界动力学的物理拓展到了非平衡光学系统,连接了量子凝聚体与激光系统。

详情
英文摘要

Universal scaling near phase transitions is one of the central ideas of physics, linking the growth of spatial correlations to the slowing down of dynamics. So far, direct experimental access to this critical behavior has remained largely confined to equilibrium many-body systems, and especially to static critical behavior. Here we probe how universality emerges in a driven quantum fluid of light formed by exciton--polaritons in a semiconductor microcavity. By probing the fluctuation-dominated disordered phase below the condensation threshold, we directly measure both the static growth of the correlation length $ξ$ and the dynamical slowing down of the relaxation time $τ$. We find that these quantities obey the universal relation $τ\propto ξ^{z}$ with dynamical exponent $z \approx 2$, revealing diffusive dynamics of a non-conserved order parameter. Our results extend the physics of critical dynamics from equilibrium matter to driven optical systems, bridging quantum condensates and lasers.

2605.02204 2026-05-11 eess.SP

When Eavesdroppers Reason: Agentic Eavesdropping Attacks on Semantic Communication

Shunpu Tang, Qianqian Yang, Zhiguo Shi, Jiming Chen, Xuemin Shen

AI总结 语义通信(SemCom)作为下一代网络的有前景范式,其端到端的联合源信道编码架构也带来了严重的隐私泄露风险。为评估此类风险,本文提出了一种基于大语言模型的智能窃听攻击方法,通过三个功能代理构建闭环工作流,无需窃听信道状态信息即可高效恢复私有信息,并进一步优化重建结果,显著提升了窃听成功率,揭示了语义通信系统亟待解决的隐私安全隐患。

详情
英文摘要

Semantic communication (SemCom) has emerged as a promising paradigm for next-generation networks. However, its typical end-to-end joint source--channel coding (JSCC) architecture also raises serious privacy concerns. To guide future secure SemCom design, it is important to understand how serious such leakage can be. Nevertheless, existing eavesdropping attacks mainly rely on fixed-configuration solvers and often require instantaneous wiretap channel state information (CSI) to achieve effective privacy inference. This may lead future secure SemCom designs to overlook potentially severe risks. To address this, we propose a large language model (LLM)-orchestrated agentic eavesdropper. Specifically, the proposed eavesdropper forms a closed-loop workflow with three functional agents. The optimization agent adaptively performs joint semantic-and-channel inversion to recover private information from the intercepted signal without requiring wiretap CSI. The perception agent evaluates the effectiveness of the optimization agent and assesses whether the recovered private semantics are reasonable, providing feedback to the optimization agent. The refinement agent further analyzes the recovered content and uses a generative prior to refine promising candidates into more realistic and complete private reconstructions while preserving consistency with the intercepted signal. Simulation results over a MIMO Rayleigh fading channel show that the proposed eavesdropper achieves more than $75\%$ eavesdropping success rate at $\mathrm{SNR}\geq 5$~dB even without wiretap CSI, highlighting a severe privacy threat that future secure SemCom systems must address.

2605.02186 2026-05-11 math.FA

Subnormal block Toeplitz operators

Mankunikuzhiyil Abhinand, Raul E. Curto, In Sung Hwang, Woo Young Lee, Thankarajan Prasad

AI总结 本文研究了块 Toeplitz 算子 $T_Φ$ 的次正规性,其中 $Φ$ 是单位圆上的 $n\times n$ 矩阵值函数,具有特定的 Blaschke–Potapov 乘积形式。作者探讨了在 $T_Φ$ 次正规的条件下,该算子是否为正规或解析,并针对不同类型的符号给出了相应的结论。此外,还给出了当 $Φ^*$ 不为有界型时,肯定结论成立的充分条件。

详情
Journal ref
JOURNAL D ANALYSE MATHEMATIQUE (2025)
英文摘要

In this paper we consider the subnormality of block Toeplitz operators $T_Φ$, where $Φ$ is an $n\times n$ matrix-valued function on the unit circle $\mathbb T$ of the form $$ Φ=QΦ^* \quad \hbox{($Q$ is a finite Blaschke--Potapov product).} $$ This is related to a matrix-valued version of Halmos's Problem 5 and Nakazi-Takahashi Theorem. We ask whether $T_Φ$ is either normal or analytic if $T_Φ$ is subnormal, where $Φ$ is of the above form. We give answers to this problem for different cases of the symbol. Moreover, we provide a sufficient condition for the answer to be affirmative when $Φ^*$ is not of bounded type.

2605.02140 2026-05-11 cond-mat.supr-con cond-mat.mes-hall

Spin-polarized Josephson current induced by inhomogeneous altermagnetic interlayers

Wenjun Zhao, Yuri Fukaya, Pablo Burset, Jorge Cayao, Yukio Tanaka, Bo Lu

AI总结 本文研究了利用非均匀反铁磁绝缘层实现无外加磁场的约瑟夫森结中自旋极化超导电流的机制。通过调控反铁磁层内奈尔矢量的取向角,研究发现约瑟夫森电流相位关系和临界电流对矢量错位角高度敏感,特定角度下可显著增强临界电流并抑制0-π转变。同时,非共线排列的奈尔矢量促使产生净自旋极化电流,揭示了自旋三重配对关联的特征,为实现无耗散自旋电子器件提供了可调的平台。

Comments 9 pages, 4 figures

详情
英文摘要

The pursuit of dissipationless spin supercurrents is a central theme in superconducting spintronics. We propose a field-free Josephson junction using an inhomogeneous altermagnetic interlayer with in-plane Néel vectors. We show that the current-phase relation and the critical Josephson current are highly sensitive to the misorientation angle between the altermagnetic layers' Néel vectors. Specifically, at a $π$ misorientation with equal layer thicknesses the spatial oscillations of the superconducting pair amplitude, governed by the center-of-mass momentum, undergo mutual cancellation. This compensation suppresses individual layer pair-breaking, significantly enhancing the critical current and eliminating $0$-$π$ transitions. Furthermore, the non-collinear alignment of the Néel vectors facilitates the emergence of a net spin-polarized Josephson current. This spin current serves as a distinct signature of spin-triplet pair correlations, generated by the spin-dependent momentum shifts inherent to the altermagnetic exchange field. Our results establish a highly tunable, field-free platform for the realization of dissipationless spintronic devices.

2605.01316 2026-05-11 cond-mat.supr-con

Impurity-Scattering Assisted Umklapp Scattering as the Origin of Low-Temperature Resistivity in the Normal-State of Cuprate Superconductors

Xingyu Ma, Minghuan Zeng, Huaiming Guo, Shiping Feng

AI总结 该研究探讨了铜氧化物高温超导体正常态中低温电阻率随温度的变化行为,发现其在欠掺杂赝能隙相中呈现二次温度依赖(T²),而在过掺杂奇异金属相中则呈现线性温度依赖(T)。研究从微观电子结构出发,揭示了杂质散射与Umklapp散射协同作用是导致这一现象的关键机制,其中杂质散射限制了分布函数的改变区域,而由杂质辅助的Umklapp散射则主导了电阻率的行为,并解释了电阻率温度尺度与赝能隙转变温度之间的关联。

Comments 15 pages, 5 figures, to be published

详情
Journal ref
Condens. Matter 11, 17 (2026)
英文摘要

The transport experiments reveal that the low-temperature resistivity in the normal-state of cuprate superconductors is quadratic in temperature (T-quadratic) in the underdoped pseudogap phase, while it is linear in temperature (T-linear) in the overdoped strange-metal phase, however, the full understanding of these different behaviours is still a challenging issue. Here starting from the microscopic electronic structure of cuprate superconductors, the low-temperature resistivity in the normal-state is investigated from the underdoped pseudogap phase to the overdoped strange-metal phase. It is shown that the mechanism requires both the impurity scattering and the umklapp scattering: the impurity scattering is needed to restrict the modification of the distribution function to at around the antinodal region,while the impurity-scattering assisted umklapp scattering from a spin excitation is at the heart of the behaviour in the low-temperature resistivity, where the doping dependence of the temperature scale exists, and presents a similar behavior of the antinodal spin pseudogap crossover temperature. In the low-temperature region above the temperature scale in the overdoped strange-metal phase, the resistivity is T-linear, however, in the low-temperature region below the temperature scale in the underdoped pseudogap phase, the opening of the spin pseudogap lowers the spin excitation density of states at around the antinodal region, which reduces the strength of the electron umklapp scattering from a spin excitation associated with the antinode, and thus leads to a T-quadratic behaviour of the resistivity.

2604.27473 2026-05-11 nucl-th hep-ph nucl-ex

Quarkonium $p_{\rm T}$ spectra in heavy--ion collisions at LHC energies within a hydrodynamic core--corona framework

Biswarup Paul

AI总结 本文在相对论流体力学框架下,系统研究了LHC能量下Pb-Pb碰撞中重子对(如J/ψ、ψ(2S)和Υ(nS))的横向动量谱,采用具有纵向 boost-invariant 扩张和类哈勃横向流的圆柱对称模型,并结合核心-晕框架考虑热和非热贡献。研究结果成功描述了ALICE和CMS实验在宽p_T范围内的测量数据,揭示了粲偶素和底偶素的产生机制,表明该方法能统一解释LHC重离子碰撞中的重子对生成现象。

Comments 7 pages and 5 figures

详情
英文摘要

We present a systematic study of the transverse momentum ($p_{\rm T}$) spectra of charmonium (J/$ψ$, $ψ(2S)$) and bottomonium ($Υ(nS)$) states in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV within an analytical relativistic hydrodynamics framework. The medium evolution is described assuming cylindrical symmetry with boost-invariant longitudinal expansion and Hubble-like transverse flow. Quarkonium spectra are evaluated using the Cooper-Frye formalism on a constant-temperature freeze-out hypersurface, supplemented by a core--corona approach to include both thermal and non-thermal contributions. The model describes the measurements from ALICE and CMS over a broad $p_{\rm T}$ range. For charmonium, both the spectra and the $ψ(2S)$/J/$ψ$ ratio are well reproduced, while deviations at high $p_{\rm T}$ for J/$ψ$ indicate additional hard production mechanisms. In the bottomonium sector, the $Υ(nS)$ spectra and their yield ratios are successfully described, consistent with the expected sequential suppression pattern. These results demonstrate that an analytical hydrodynamic approach combined with a core-corona framework provides a unified and transparent description of quarkonium production in heavy--ion collisions at LHC energies.

2604.26603 2026-05-11 math.CO math.AC

On main eigenvalues of zero-divisor graphs of reduced rings

Sakshi Jain, Y. M. Borse, R. Barabde

AI总结 本文研究了零因子图的主特征值问题,旨在构造具有恰好 $s \ge 2$ 个主特征值的无限简单连通图族。通过利用约化环的零因子图结构及其等距划分的谱性质,作者证明这类图构成满足条件的无限图族,并进一步指出某些诱导的二分图也具有相同数量的主特征值,为谱图论提供了新的例子和分析工具。

Comments 14 pages, 1 figure

详情
英文摘要

The problem of characterizing graphs with a prescribed number of main eigenvalues is a long-standing problem in spectral graph theory. Although some constructions are known, only a few produce infinite families of simple connected graphs with exactly $s \ge 2$ main eigenvalues. Zero-divisor graphs form a well-structured class of algebraic graphs whose spectra can be described explicitly using equitable partitions, making them a convenient setting to study main eigenvalues. In this paper, we prove that the zero-divisor graphs of reduced rings provide an infinite family of simple connected graphs with exactly $s$ main eigenvalues, and that certain induced bipartite subgraphs also have exactly $s$ main eigenvalues for any positive integer $s$.

2604.25826 2026-05-11 econ.GN q-fin.EC stat.AP

General-Purpose Technology and Speculative Bubble Detection

Haiqiang Chen, Li Chen, Difang Huang, Yuexin Li, Zhengjun Zhang

AI总结 本文研究了通用技术采用对资产价格泡沫检测的影响,指出传统泡沫检验方法在考虑技术冲击时存在严重的规模扭曲。作者通过在Campbell-Shiller现值模型中引入驼峰形技术冲击,证明技术采用期间基本价格会出现局部爆炸性增长,从而影响检验的极限分布。为此,提出将价格分解为基本价值与投机成分的方法,实证分析表明该方法能有效区分2020-2025年AI热潮中的投机行为,并确认了1999年12月至2000年3月的互联网泡沫高峰期。

详情
英文摘要

We show that the leading bubble test suffers severe size distortion when fundamentals incorporate general-purpose technology adoption. Embedding a hump-shaped technology shock in the Campbell-Shiller present-value model, we prove that the fundamental price becomes locally explosive during adoption, contaminating the test's limit distribution with a non-centrality parameter proportional to the shock's peak. We propose a fundamental-versus-speculative decomposition that projects prices onto observable technology proxies and applies the test to the residual. Empirically, the decomposition eliminates evidence of speculation in the 2020-2025 AI rally while confirming a speculative peak confined to December 1999-March 2000 in the dot-com episode.

2604.25610 2026-05-11 quant-ph

Optimizing ground state preparation protocols with autoresearch

Luis Mantilla Calderón, Jérôme F. Gonthier, Ignacio Gustin, Varinia Bernales, Alán Aspuru-Guzik

AI总结 本文研究了如何利用基于语言模型的自动编程代理(autoresearch)优化量子基态制备协议中的超参数选择,涉及变分量子本征求解器(VQE)、密度矩阵重整化群(DMRG)和辅助场量子蒙特卡洛(AFQMC)等方法。通过在简单自旋模型和分子哈密顿量上验证,展示了该方法能够在计算资源受限的情况下,将基础协议优化为更复杂的高性能协议,显著提升能量估计等收敛指标。这一成果为自动化量子算法调优提供了新的可行路径。

Comments 18 pages, 5 figures

详情
英文摘要

Artificial intelligent language-model based coding agents have significantly changed the way we interact with computers in our day-to-day, as it is common to use them to create, improve, and run programming scripts only using natural language. Agent code updates can be better guided when such programs can be executed and scored automatically rather than judged by human preference. In quantum computing and classical quantum simulation settings, ground-state preparation has a parallel structure: candidate protocols can be ranked by estimated energies and other proxies indicating proper quantum-state convergence. In this work, we study how autoresearch, a code optimization strategy based on coding agents, can be used to optimize hyperparameter choices of different ground-state preparation and sampling protocols, including the variational quantum eigensolver (VQE), density matrix renormalization group (DMRG), and auxiliary-field quantum Monte Carlo (AFQMC). We validate the viability and capacity of this method on simple spin models and molecular Hamiltonians. Across all three settings, the agent mutates simple baselines into complex protocols with improved energy proxies while operating under constrained space-time computational budgets. We conclude with discussions of other quantum routines that support executable scalar scoring, enabling evolutionary coding agents to automate a substantial portion of the protocol-tuning work that would otherwise be required manually.

2604.24206 2026-05-11 math.OA

The real and stable rank of tracially complete C*-algebras

Samuel Evington, Aaron Tikuisis

AI总结 本文研究了具有CPoU性质的因子型迹全C*-代数的实秩与稳定秩,证明其具有零实秩和一稳定秩。这一结果为这类代数的Cuntz半群提供了本质完整的描述,特别地,文中结论适用于$\mathcal{Z}$-稳定C*-代数的统一迹完备化。

Comments 14 pages; submitted version

详情
英文摘要

We prove that a factorial tracially complete C*-algebra with CPoU has real rank zero and stable rank one. This leads to an essentially complete description of the Cuntz semigroup of these algebras. In particular, the results of this paper hold for the uniform tracial completions of $\mathcal{Z}$-stable C*-algebras.

2604.22915 2026-05-11 hep-th

Heterotic Ouroboros

Chiara Altavista, Salvatore Raucci, Angel M. Uranga, Chuying Wang

AI总结 本文研究了M理论在${\mathbf{S}}^1\vee{\mathbf{S}}^1$背景下的紧致化,旨在通过商空间构造得到十维非超对称杂弦理论。作者重新考察了杂弦理论的构建方法,提出了一套一致的规则,能够准确描述轻子谱和规范群结构,并提供了它们整体结构的线索。研究中应用了型I'弦理论中的规范增强机制,并将型I'弦的区间卷曲成自身,利用分支切割处理边界条件,从而重现了十维杂弦理论,并为不同理论之间的联系提供了证据。

Comments 37 pages, 11 figures; references added

详情
英文摘要

M-theory on ${\mathbf{S}}^1\vee{\mathbf{S}}^1$ has recently been proposed to yield, via quotients, ten-dimensional non-supersymmetric string theories. We revisit the construction that leads to the heterotic theories, finding a consistent set of rules that reproduces the light spectra and gauge groups, including indications of their global structure. Our approach uses the gauge enhancement mechanism of type I' string theory, applied to a setting in which the type I' interval is curled onto itself, with its two boundaries separated by a branch cut. Using these tools, we reproduce the ten-dimensional heterotic theories and provide some evidence for junctions among them.

2604.19568 2026-05-11 cs.GR

SpUDD: Superpower Contouring of Unsigned Distance Data

Ningna Wang, Xiana Carrera, Christopher Batty, Oded Stein, Silvia Sellán

AI总结 本文研究如何从无符号距离数据的有限采样点重建任意曲面的问题。不同于依赖符号信息、梯度或连续距离函数的传统方法,作者提出了一种基于距离样本生成的幂图的新型理论概念——超幂轮廓,并证明其在采样密度趋于无穷时收敛于真实曲面。该方法利用超幂轮廓作为初始曲面代理,设计了一种生成逼近真实几何的多边形网格的算法,显著优于其他离散无符号距离重建策略,为该数学问题的进一步研究奠定了基础。

详情
英文摘要

Unsigned distance functions offer a powerful and flexible implicit surface representation that, unlike their signed counterparts, allow for surfaces that are open, non-orientable, or non-manifold. We consider the problem of reconstructing arbitrary surfaces from a finite set of samples of unsigned distance data. Existing methods for mesh reconstruction from distance data rely on sign information, accurate gradients, a corresponding continuous distance function, or extensive data-dependent training. However, they fail when applied to input that is both discrete and unsigned. Inspired by this challenge, we study the power diagram generated by the distance samples and propose a novel theoretical concept, the superpower contour, which we prove converges to the true surface in the limit of sampling density. We use this superpower contour as an initial surface proxy and design an algorithm that leverages it to produce a polygonal mesh approximating the unknown true geometry. Our method vastly outperforms other conceivable strategies for the discrete unsigned distance reconstruction task, and sets the stage for future work on this mathematically rich problem.