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2605.22950 2026-05-25 stat.ML cs.LG math.ST stat.ME stat.TH

Diffusion-based Denoising Beats Vanilla Score Matching in Parameter Estimation: A Theoretical Explanation

基于扩散的去噪在参数估计中优于普通得分匹配:一个理论解释

Benedikt Lütke Schwienhorst, Nadja Klein, Johannes Lederer

AI总结 本文研究了在多峰分布参数估计中,基于扩散的去噪分数匹配方法相较于传统分数匹配方法的优越性,并给出了理论解释。作者提出了一种新的扩散去噪分数匹配估计器(DDSME),并通过理论分析证明,传统分数匹配估计器在峰间距离增大时误差会恶化,而DDSME通过适当调节超参数可避免这一问题。该研究为扩散模型在参数估计中的优势提供了新的理论依据。

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AI中文摘要

当归一化常数未知或计算成本过高时,得分匹配是最大似然估计的替代方法。然而,对于实际应用中常见的具有良好分离模态的多峰分布,普通得分匹配相对于最大似然估计效率较低。我们在此场景下比较了一种新颖的基于扩散的去噪得分匹配估计器(DDSME)与普通得分匹配估计器(SME)。特别地,我们证明了两种估计器的统计保证,表明普通SME的误差界随着模态间分离度的增加而恶化,而通过适当的超参数调整,DDSME可以避免这一问题。这为基于扩散的得分匹配优于普通版本的行为提供了新的理论解释。

英文摘要

Score matching is an alternative to maximum likelihood estimation when the normalizing constant is unknown or too costly to evaluate. However, vanilla score matching has shown to be inefficient relative to maximum likelihood estimation for multimodal distributions with well-separated modes, which are commonly encountered in practical applications. We compare a novel diffusion-based denoising score matching estimator (DDSME) to the vanilla score matching estimator (SME) in this scenario. In particular, we prove statistical guarantees for both estimators, showing that the error bound for the vanilla SME worsens when the separation between the modes increases, which can be avoided in case of the DDSME with suitable hyperparameter tuning. This provides a novel theoretical explanation for the superior behavior of diffusion-based score matching over the vanilla version.

2605.23682 2026-05-25 eess.SP

Tri-Domain Multiuser MIMO Precoding Optimization and Channel Estimation with Spatial-EM Reconfigurable Antenna

三域多用户MIMO预编码优化与空间-电磁可重构天线的信道估计

Yining Li, Ziwei Wan, Zhen Gao, Keke Ying, Lipeng Zhu, Rui Zhang

AI总结 本文提出了一种三域可重构多用户MIMO通信系统,整合了电磁可重构天线(EMRA)与空间可移动天线(SMA),称为空间-电磁可重构天线(SEMRA)。该系统提供了电磁、空间和数字域的自由度,用于联合信道重构,但同时也带来了信道估计(CE)和预编码优化的新挑战。文中提出了一种基于加权最小均方误差(WMMSE)的三域联合优化算法,以提升频谱效率(SE),并设计了一种低开销的移动辅助信道估计方案,通过协调天线重新定位生成更密集的虚拟阵列,实现更准确的角度离开估计和电磁域信道状态信息(eCSI)重构。仿真结果表明,所提的信道估计方案提升了eCSI估计精度,所提的SEMRA在相同试点开销下实现了更高的频谱效率。

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AI中文摘要

本文提出了一种三域可重构多用户多输入多输出(MIMO)通信系统,该系统将电磁(EM)可重构天线(EMRA)与空间可移动天线(SMA)相结合,称为空间-电磁可重构天线(SEMRA)。所提出的系统提供了电磁、空间和数字域自由度(DoFs)用于联合信道重构,但也引入了信道估计(CE)和预编码优化的新挑战。具体而言,对于多用户正交频分复用(OFDM)下行链路,预编码设计被表述为一个三域优化问题,涉及天线位置、电磁域辐射方向图权重和数字预编码器。我们首先开发了一种基于迫零(ZF)的基线算法来解耦空间重构的设计,然后提出了一种基于加权最小均方误差(WMMSE)的三域联合优化算法,以进一步提高频谱效率(SE)。此外,我们提出了一种低开销的移动辅助信道估计方案,其中跨导频时隙的协调天线重新定位合成更密集的虚拟阵列,从而在相同每用户导频开销下,相比EMRA基线实现更精确的离开角(AoD)估计和电磁域信道状态信息(eCSI)重构。所得的参数化表示使得无需额外导频即可在期望天线位置组装eCSI。仿真结果表明,所提出的CE方案提高了eCSI估计精度,并且在相同导频开销下,所提出的SEMRA比EMRA基线实现了更高的SE。

英文摘要

In this paper, we propose a tri-domain reconfigurable multiuser multiple-input multiple-output (MIMO) communication system that integrates the electromagnetic (EM) reconfigurable antenna (EMRA) with the spatially movable antenna (SMA), termed the spatial-EM reconfigurable antenna (SEMRA). The proposed system offers EM, spatial, and digital domain degrees of freedom (DoFs) for joint channel reconfiguration, yet introduces new challenges in channel estimation (CE) and precoding optimization. Specifically, for multiuser orthogonal frequency division multiplexing (OFDM) downlink, the precoding design is formulated as a tri-domain optimization problem over antenna positions, EM-domain radiation-pattern weights, and digital precoders. We first develop a zero-forcing (ZF)-based baseline algorithm to decouple the design of spatial reconfiguration, and then propose a weighted minimum mean square error (WMMSE)-based tri-domain joint optimization algorithm for further improving the spectral efficiency (SE). Furthermore, we propose a low-overhead movement-aided channel estimation scheme in which coordinated antenna repositioning across pilot slots synthesizes a denser virtual array, enabling more accurate angle-of-departure (AoD) estimation and EM-domain channel state information (eCSI) reconstruction under the same per-user pilot overhead as the EMRA baseline. The resulting parametric representation enables eCSI assembly at desired antenna positions without additional pilots. Simulation results show that the proposed CE scheme improves eCSI estimation accuracy and the proposed SEMRA achieves higher SE than the EMRA baseline under the same pilot overhead.

2605.23681 2026-05-25 math.CO

New invariants for rank metric codes, with applications to the classification of rank two semifields of order 256

秩度量码的新不变量及其在256阶秩二半域分类中的应用

Jack Gilchrist, Stefano Lia, Arani Paul, John Sheekey

AI总结 本文提出新的不变量用于半字段的分类,并结合新的计算技术,显著提高了对秩为2的半字段的分类效率。研究重点在于对阶为256的半字段进行完整分类,特别关注其核的阶为16的情况。新方法在理论和计算上均有所突破,为相关领域的进一步研究提供了重要工具。

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AI中文摘要

在本文中,我们完全分类了包含 $2^4=16$ 阶核的 $2^8=256$ 阶半域。我们引入了半域的新不变量,并应用了新的计算技术来计算旧不变量。这些使得计算分类显著加快。

英文摘要

In this paper we completely classify semifields of order $2^8=256$ containing a nucleus of order $2^4=16$. We introduce new invariants for semifields, and apply new computational techniques for calculating old invariants. Together these make the computational classification significantly quicker.

2605.23680 2026-05-25 astro-ph.EP

Modeling (Sub-)millimeter Scattering Properties of Fractal and Consolidated Porous Particles: Applications to Protoplanetary Disks

分形和多孔凝聚颗粒的(亚)毫米散射特性建模:对原行星盘的应用

Gonzalo Vargas, Daniel Guirado, Carlos Carrasco-Gonzalez, Olga Munoz, Maxim A. Yurkin, Enrique Macias, Jesus M. Jaquez-Dominguez, Francisco J. Garcia-Izquierdo

AI总结 本文研究了 fractal 和压实多孔颗粒在亚毫米波段的散射特性,应用于原行星盘模型。通过离散偶极近似(ADDA)和多球 T 矩方法(MSTM)分别计算了压实多孔颗粒和高度多孔聚集体的散射矩阵、截面及有效反照率。研究发现,孔隙率增加会增强前向散射并增强接近 90 度时的偏振特性。结果表明,多孔颗粒在较大尺寸时仍能保持与反照率约束一致的特征,同时孔隙率还能降低固定尘埃质量下的吸收系数,暗示在给定连续谱辐射下,推导出的尘埃质量更大。

Comments 18 pages, 8 figures, 8 tables. Accepted for publication in The Astrophysical Journal

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AI中文摘要

我们对两种尘埃群体进行了光散射数值模拟:(i) 使用离散偶极子近似(ADDA)计算的致密多孔颗粒,以及(ii) 使用多球T矩阵方法(MSTM)计算的高度多孔聚集体模型,包括分形和层次聚集体。使用DSHARP光学常数,我们计算了尺寸分布n(a) ∝ a^q(q = -3.5,amin = 0.1微米)在0.87至10毫米十个波长下的散射矩阵、截面和有效反照率ω_eff。我们发现,增加孔隙率会增强前向散射,并增强θ约90度附近的极化。对于致密球体,P(90度) × ω_eff在amax ≈ λ/(2π)附近达到峰值然后下降,而多孔颗粒则显示出延伸到更大尺寸的更宽峰值,使基于极化的约束与amax ≈ 1毫米兼容。相对于致密球体,孔隙率还降低了固定尘埃质量下的κ_abs,意味着对于给定的连续谱通量,推断的尘埃质量更大。

英文摘要

We perform light-scattering numerical simulations for two dust populations: (i) consolidated porous particles computed with the discrete dipole approximation (ADDA) and (ii) highly porous aggregate models, including fractal and hierarchical aggregates, computed with the multiple-sphere T-matrix method (MSTM). Using DSHARP optical constants, we compute scattering matrices, cross sections, and effective albedo omega_eff for a size distribution n(a) proportional to a^q, with q = -3.5, amin = 0.1 micron, and ten wavelengths from 0.87 to 10 mm. We find that increasing porosity strengthens forward scattering and enhances polarization near theta approximately 90 degrees. For compact spheres, P(90 degrees) times omega_eff peaks near amax approximately lambda divided by 2 pi and then declines, whereas porous particles show a broader peak extending to larger sizes, keeping polarization-based constraints compatible with amax approximately 1 mm. Porosity also lowers kappa_abs at fixed dust mass relative to compact spheres, implying larger inferred dust masses for a given continuum flux.

2605.23679 2026-05-25 math.GT math.DG

Geometrisation of 3-manifolds

三维流形的几何化

Bruno Martelli

AI总结 三维流形的几何化理论自20世纪80年代由Thurston提出猜想,直至21世纪初由Perelman完成证明。本文对这一理论进行了概述,阐述了定理的核心内容及其在不同情境下的应用与影响。

Comments 27 pages, 26 figures

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AI中文摘要

三维流形的几何化定理由瑟斯顿在1980年代猜想,并由佩雷尔曼在2000年代证明。本文是该主题的概述。我们解释了定理的内容,并描述了它在各种情况下的影响。

英文摘要

The geometrisation theorem of 3-manifolds was conjectured by Thurston the 1980s and proved by Perelman in the 2000s. This is an overview on the subject. We explain the content of the theorem and describe its effects in various situations.

2605.23678 2026-05-25 math.OC

Concentration of measure-valued solutions for semilinear parabolic equations

半线性抛物型方程的测度值解的集中性

Charlie Lebarbé, Émilien Flayac, Michel Fournié, Didier Henrion, Milan Korda

AI总结 本文研究了半线性抛物型方程的测度值解的集中现象。作者证明了对于反应扩散类型的标量半线性抛物型偏微分方程,不存在松弛间隙,即线性测度形式的解能够对应于原方程的经典物理解。通过展示每个测度方程的解都能生成满足合适能量恒等式的能量测度值解,并证明此类解在非线性PDE解存在且唯一时会集中于其上,为反应扩散型PDE的测度值解理论提供了重要贡献。

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AI中文摘要

矩-平方和层次结构通过构造一系列凸半定松弛为解决非凸最优控制问题提供了强大框架。然而,当将这些方法扩展到非线性偏微分方程(PDE)时,一个基本挑战是可能存在松弛间隙,即使用占用测度的线性测度公式的解无法对应原始PDE的经典物理解。在本文中,我们证明了标量半线性反应扩散型抛物型PDE不存在松弛间隙。我们通过证明线性测度方程的每个解在满足适当能量恒等的Young测度空间中产生一个能量测度值(emv)解来做到这一点。然后我们证明,只要非线性PDE的解存在且唯一,任何这样的emv解都集中在该非线性PDE的解上。据我们所知,这是关于反应扩散型PDE的测度值解的第一个此类集中性结果。

英文摘要

The moment-sum-of-squares hierarchy provides a powerful framework for solving non-convex optimal control problems by constructing a sequence of convex semidefinite relaxations. However, when extending these methods to nonlinear partial differential equations (PDEs), a fundamental challenge is the potential existence of a relaxation gap, where the solution to the linear measure formulation using occupation measures fails to correspond to a classical physical solution of the original PDE. In this paper, we prove the absence of a relaxation gap for scalar semilinear parabolic PDEs of the reaction-diffusion type. We do so by showing that each solution to the linear measure equation gives rise to an energy measure-valued (emv) solution in the space of Young measures satisfying suitable energy identities. We then prove that any such emv solution concentrates on the solution to the nonlinear PDE, provided the latter exists and is unique. To the best of our knowledge, this is the first concentration result of this kind for measure-valued solutions of reaction-diffusion PDEs.

2605.23677 2026-05-25 cs.DC

AMP: Arc Multi-Proposer Protocol with Bounded Inclusion Guarantees

AMP:具有有界包含保证的弧多提议者协议

Daniel Cason, Gordon Liao, Sergio Mena, Nenad Milošević, Adi Seredinschi, Alessandro Sforzin, João Sousa, Preston Vander Vos

AI总结 AMP是一种基于Tendermint共识算法的多提案协议,旨在解决区块链系统中单个验证者对交易包含和排序的绝对控制问题。该协议引入了专门的提案节点,负责收集用户交易并广播至所有验证者,从而消除传统内存池的依赖,实现传播与共识的分离,提升系统吞吐量。通过验证者对提案的公开证明和共识机制,AMP确保每个提案在满足条件后被纳入下一个区块,从而限制了单个验证者的控制权,增强了区块链金融基础设施的公平性和安全性。

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AI中文摘要

处理金融交易的区块链系统面临结构性紧张:组装每个区块的单一验证者对交易包含和排序拥有单边权力。传统市场通过抢先交易和市场操纵法律来遏制这种权力。监管机构已指出缺乏此类规则是基于区块链的金融基础设施的一级关注点。为此,我们在Tendermint共识算法之上引入AMP,一种多提议者协议,其中没有验证者可以控制交易流入区块。相反,称为提议者的专用节点位于用户和验证者之间。他们收集用户交易,将其分组为有效载荷,并将有效载荷广播给所有验证者。因此,没有mempool,AMP应用了分离传播与共识的设计原则,这可以带来更高的吞吐量。验证者公开证明接收到有效载荷,并运行共识来决定下一区块中包含的有效载荷集合。当所有正确的验证者证明给定有效载荷时,AMP保证该有效载荷将被包含在下一区块中;因此一个区块包含来自多个提议者的有效载荷,允许批量终结。这种有界包含保证以及运行在区块中包含的所有有效载荷上的确定性排序算法,遏制了任何单个验证者的权力。验证者不再控制区块中包含的内容,也不能任意排序区块的内容。

英文摘要

Blockchain systems that settle financial transactions face a structural tension: the single validator that assembles each block holds unilateral power over transaction inclusion and ordering. Traditional markets curb this very power through front-running and market-manipulation laws. Regulators have flagged the absence of such rules as a first-order concern for blockchain-based financial infrastructure. In response, we introduce AMP, a multi-proposer protocol, on top of the Tendermint consensus algorithm, where no validator can control the flow of transactions into blocks. Instead, dedicated nodes called proposers sit between users and validators. They collect user transactions, group them into payloads, and broadcast the payloads to all validators. Consequently, there is no mempool, and AMP applies the design principle of separating dissemination from agreement, which can lead to higher throughput. Validators publicly attest to receiving payloads and run consensus to decide the set of payloads to include in the next block. When all correct validators attest to a given payload, AMP guarantees that payload will be included in the next block; a block thus contains payloads from multiple proposers, allowing for bulk finalization. This bounded inclusion guarantee along with a deterministic ordering algorithm which is run over all payloads included in a block, curbs the power of any single validator. Validators no longer control what is included in a block, nor can they arbitrarily order the contents of blocks.

2605.23676 2026-05-25 cs.HC

AI at the Front Lines of Platform Governance: Using LLMs to Support Illegal Content Reporting under the Digital Services Act

平台治理前线的AI:利用大语言模型支持《数字服务法案》下的非法内容举报

Marie-Therese Sekwenz, Shreyan Biswas, Rita Hermann-Gsenger, Ujwal Gadiraju

AI总结 本文探讨了如何利用大型语言模型(LLM)辅助用户在欧盟《数字服务法》框架下更有效地报告非法内容。研究通过 controlled 用户实验,比较了无辅助报告、传统可解释AI助手(XAI)以及评估型AI助手(EvalAI)在不同AI错误情境下的表现。结果表明,EvalAI在AI错误情况下能提升报告准确性并减少误分类距离,但传统XAI在AI输出正确时可加快决策速度。研究揭示了合规型报告界面设计中的权衡问题,强调了准确性、 deliberation、解释质量与AI误导风险之间的平衡。

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AI中文摘要

非法内容举报机制是在欧盟《数字服务法案》(DSA)下,在线平台处理非法内容的关键技术性和组织性措施。第16条要求用户通知必须充分证实并善意提交,这使用户处于解释法律和程序语言、将模糊内容转化为具有法律意义的类别和理由的困难境地。我们研究了基于大语言模型(LLM)的助手如何支持这一举报过程。在一项受控用户研究(N=450)中,使用基于主要平台举报工作流程建模的界面,我们比较了三种条件:无辅助举报、传统可解释AI助手(XAI)——建议单一法律类别并附理由,以及评估性AI助手(EvalAI)——在候选法律条款中呈现平衡的正反论点。我们进一步在系统变化的AI错误机制下检验了这些辅助形式。结果显示,在AI错误时,EvalAI相对于传统XAI提高了条款级准确性并减少了误分类距离,特别是对于接近命中(near-miss)和过度宽泛(overbreadth)错误。当AI输出正确时,传统XAI能实现更快的决策,但两种AI辅助形式相对于无辅助举报均未可靠地提高用户实质性解释的质量。我们讨论了面向合规的举报界面的设计启示,强调了准确性、深思熟虑、解释质量和对误导性AI输出的脆弱性之间的权衡。

英文摘要

Illegal content reporting mechanisms are a key technical and organizational measure through which online platforms address illegal content under the European Union Digital Services Act (DSA). Article 16 requires user notices to be sufficiently substantiated and submitted in good faith, placing users in the difficult position of interpreting legal and procedural language and translating ambiguous content into legally meaningful categories and reasons. We investigate how large language model (LLM)-based assistants can support this reporting process. In a controlled user study (N = 450) using an interface modeled on a major platform reporting workflow, we compare three conditions: unaided reporting, a conventional explainable AI assistant (XAI) that suggests a single legal category with a rationale, and an evaluative AI assistant (EvalAI) that presents balanced pro and con arguments across candidate legal provisions. We further examine these assistance forms under systematically varied AI error regimes. Our results show that EvalAI improves provision-level accuracy under AI error and reduces misclassification distance relative to conventional XAI, particularly for near-miss and overbreadth errors. When AI output is correct, conventional XAI enables faster decisions, but neither AI assistance form reliably improves the quality of users' substantiated explanations relative to unaided reporting. We discuss design implications for compliance-oriented reporting interfaces, highlighting trade-offs between accuracy, deliberation, explanation quality, and vulnerability to misleading AI output.

2605.21678 2026-05-25 astro-ph.SR

29SiO and 30SiO J=1--0 maser signatures in Galactic AGB stars: the impact of third dredge up and turbulence velocity

29SiO 和 30SiO J=1--0 脉泽在银河系 AGB 星中的特征:第三次挖掘和湍流速度的影响

M. O. Lewis, L. O. Sjouwerman, Y. M. Pihlström, H. J. van Langevelde, R. Bhattacharya, M. C Stroh

AI总结 29SiO和30SiO的J=1--0毫米波跃迁在银河系渐近巨星分支(AGB)星中表现出独特的maser特征,研究发现这一特征与第三混合层上升及低湍流速度有关。通过分析红外颜色选择的BAaDE调查数据,研究人员识别出35个主要由同位素跃迁主导的maser谱线(iso-dom谱)。研究指出,这些谱线增强可能源于第三混合层上升带来的同位素丰度变化以及低湍流速度导致的谱线重叠效应,从而有效泵浦maser跃迁。

Comments 17 pages, 4 figures, 3 tables, accepted by A&A

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AI中文摘要

43 GHz 的 J=1--0 SiO 脉泽在渐近巨星分支(AGB)星中具有明确特征。28SiO 跃迁通常主导这些谱线,其中 v=1 和 v=2 发射尤为突出且普遍存在。关于奇特星中 29SiO 丰度增强的若干预测促使我们编录 29SiO 脉泽发射相对于 28SiO 增强的案例。我们的目的是编录已知的由同位素体跃迁发射主导的 43 GHz 谱(iso-dom 谱)案例,探索这些源的共性,并解释此类脉泽特征的成因。我们的编录来自红外颜色选择的 BAaDE 巡天中的 SiO 脉泽线比,并辅以文献探测。BAaDE 编录巩固了 43 GHz SiO 脉泽的典型特征,显示其由 v=1 和 v=2 线主导。识别出 35 个 iso-dom 谱,意味着该特征出现在约 0.2% 的含 SiO 脉泽星中。与同周期的其他源相比,它们的红外颜色偏蓝,类似于所有显示同位素体脉泽的源。显然,源的 iso-dom 性质是可变的,但尚不清楚这是否与恒星相位有关。iso-dom 源中较大的丰度异常不被支持,因为 iso-dom 源与其他拥有同位素体脉泽的星并无显著差异。脉泽抽运影响特定跃迁的粒子数反转,可以解释增强的特征。我们假设 iso-dom 谱出现在经历过第三次挖掘(轻微增强 29SiO 和 30SiO 丰度)且同时经历极低湍流速度(<1 km/s)的 AGB 星中,从而产生线重叠,非常有效地抽运脉泽跃迁。

英文摘要

J=1--0 SiO masers at 43 GHz have a well-established distinctive signature in asymptotic giant branch (AGB) stars. 28SiO transitions typically dominate these spectra with the v=1 and v=2 emission being especially prominent and ubiquitous. Several predictions about enhanced 29SiO abundances in exotic stars prompt us to catalog the cases where 29SiO maser emission is enhanced compared to 28SiO. Our purpose is to catalog the known cases of 43 GHz spectra dominated by emission from isotopologue transitions (iso-dom spectra), to explore the commonalities in these sources, and to explain the cause of such maser signatures. Our catalog is drawn from SiO maser line ratios in the infrared-color-selected BAaDE survey and supplemented with a literature detection. The BAaDE catalog has cemented the typical signature of 43 GHz SiO masers, showing it is dominated by the v=1 and v=2 lines. Thirty-five iso-dom spectra are identified, meaning that this signature is seen in about 0.2% of our SiO maser-bearing stars. Their infrared colors are blue compared to other sources of the same period, similar to all sources displaying isotopologue masers. It is clear that the iso-dom nature of sources is variable, but unclear whether this is tied to stellar phase. A large abundance abnormality among the iso-dom sources is disfavored as the iso-dom sources do not appear significantly different from other stars which host isotopologue masers. Maser pumping, affecting the population inversions of specific transitions, can instead explain the enhanced signatures. We posit that iso-dom spectra appear in AGB stars which have undergone third-dredge up (enhancing the 29SiO and 30SiO abundance slightly) and which, in addition, are experiencing very low turbulence velocity (<1 km/s), creating a line overlap which pumps the maser transitions very efficiently.

2605.16526 2026-05-25 astro-ph.SR astro-ph.HE

SN 2023fyq: direct detection of a Type Ibn supernova progenitor and its multi-wavelength environmental constraints

SN 2023fyq:Ibn型超新星前身星的直接探测及其多波段环境约束

Xinyi Hong, Ning-Chen Sun, Yali Shao, Ke Wang, Junjie Wu, Qiang Xi, Yi-Han Zhao, Justyn Maund, Xiaohan Chen, Anyu Wang, Linxi Zhang, Jifeng Liu

AI总结 SN 2023fyq 是首颗直接探测到前身星的 Type Ibn 型超新星,其前身星被确认为一颗高温高光度的恒星,并可能属于一个恒星团。研究通过多波段数据揭示了前身星的环境特征,支持其为双星系统中的低质量氦星与致密天体相互作用的产物,为 Type Ibn 超新星的形成机制提供了新的证据。

Comments 12 pages, 11 figures

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AI中文摘要

背景。Ibn型超新星(SNe)以来自抛射物-星周介质相互作用的窄氦发射线为特征,但其前身星仍有争议,提出了大质量沃尔夫-拉叶星和双星中的低质量氦星两种可能。目标。我们旨在直接识别Ibn型超新星SN 2023fyq的前身星,并表征其环境,以约束前身星的性质和演化通道。方法。我们基于爆炸前和晚期的HST和JWST图像搜索超新星前身星,并通过拟合光谱能量分布推导其性质。我们利用包括HST和JWST成像、VLT/MUSE积分场单元光谱和ALMA CO (2--1)射电干涉测量的多波段数据集,通过探测恒星、尘埃、电离气体和分子气体来研究超新星环境。结果。我们在超新星位置发现了一个爆炸前源,该源与一个高温($T>$15000 K)且明亮(log($L$/$L_\odot$) $\gtrsim$ 5.5)的超新星前身星以及一个可能的宿主星团一致。该前身星被证实在爆炸后消失。对超新星环境的分析表明,前身星的年龄可能为log($t$/yr) = 7.1--7.2。这些现象不利于非常巨大的单星前身星,而是支持涉及低质量氦星和致密天体的双星场景;观测到的前身星发射可能源于至少在爆炸前$\sim$12年开始的双星相互作用。结论。SN 2023fyq是第一个直接探测到前身星和可能宿主星团的Ibn型超新星。它增加了Ibn型超新星在前身星通道和质量损失机制方面的多样性。

英文摘要

Context. Type Ibn supernovae (SNe) are characterized by narrow helium emission lines arising from ejecta-circumstellar medium interaction, yet their progenitors remain debated, with both massive Wolf-Rayet stars and low-mass helium stars in binaries proposed. Aims. We aim to directly identify the progenitor of the Type Ibn SN 2023fyq and to characterize its environment in order to constrain the progenitor's nature and evolutionary channel. Methods. We search for the SN progenitor based on pre-explosion and late-time HST and JWST images and derive its properties by fitting the spectral energy distribution. We investigate the SN environment by probing the stars, dust, ionized gas and molecular gas with a multi-wavelength dataset including HST and JWST imaging, VLT/MUSE integral-field-unit spectroscopy and ALMA CO (2--1) radio interferometry. Results. We discover a pre-explosion source at the SN position, which is consistent with a hot ($T>$15000 K) and luminous (log($L$/$L_\odot$) $\gtrsim$ 5.5) SN progenitor and a possible host star cluster. The progenitor is confirmed to have disappeared after explosion. Analysis of the SN environment implies that the progenitor likely has an age of log($t$/yr) = 7.1--7.2. These phenomena disfavor a very massive single-star progenitor and instead support a binary scenario involving a low-mass helium star and a compact object; the observed progenitor emission likely arises from binary interaction that began at least $\sim$12 yr before the explosion. Conclusions. SN 2023fyq is the first Type Ibn SN with a directly detected progenitor and a possible host star cluster. It adds to the diversity of Type Ibn SNe in terms of their progenitor channels and mass-loss mechanisms.

2605.23900 2026-05-25 hep-th

What to do with a Ricci-flat Calabi--Yau metric?

如何处理 Ricci-flat Calabi-Yau 度量?

Per Berglund, Tristan Hübsch, Vishnu Jejjala

AI总结 本文探讨了在弦论紧致化中,如何利用数值计算得到的里奇平坦卡拉比-爱因斯坦度量来获取新的物理和数学信息。传统上,紧致化的研究主要依赖于拓扑和全纯数据,而数值度量使得计算物质凯勒度量、约化耦合、卡鲁扎-克莱因谱等非全纯物理量成为可能。此外,该方法还为模稳定、α'修正背景、德西特模型构建等重要问题提供了定量输入,并为研究特殊拉格朗日子流形、镜像对称等数学问题开辟了计算途径。

Comments 50 pages, for Proceedings of "Recent Progress in Computational String Geometry'' workshop, BIRS/CMI, 2026

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AI中文摘要

Ricci-flat Calabi-Yau 度量的数值近似使得超越传统上主导显式弦紧致化的拓扑和全纯数据成为可能。本文解释了一旦度量以及最终的 Hermitian Yang-Mills 丛数据可以计算,哪些新的物理和数学变得可访问。在杂化紧致化中,这些数据对于确定物质 Kähler 度量、规范归一化的 Yukawa 耦合、Kaluza-Klein 谱、阈值效应、软项以及四维有效作用量的其他非全纯成分是必需的。更广泛地说,数值 Calabi-Yau 几何为模稳定化、α'修正背景、de Sitter 模型构建、轴子物理、沼泽地距离测试以及内几何随时空变化的紧致化提供了定量输入。几何数据允许对涉及特殊拉格朗日子流形、SYZ 纤维化、镜像对称、校准几何、度量退化、Ricci-flat 度量到纤维的限制以及解析或半解析结构搜索的长期数学问题进行计算研究。我们将这些方向作为未来工作的路线图。

英文摘要

Numerical approximations to Ricci-flat Calabi--Yau metrics make it possible to move beyond the topological and holomorphic data that have traditionally dominated explicit string compactifications. This article explains what new physics and mathematics become accessible once the metric, and eventually the associated Hermitian Yang--Mills bundle data, can be computed. In heterotic compactifications, such data are needed to determine matter Kähler metrics, canonically normalized Yukawa couplings, Kaluza--Klein spectra, threshold effects, soft terms, and other non-holomorphic ingredients of the four-dimensional effective action. More broadly, numerical Calabi--Yau geometry provides quantitative input for moduli stabilization, $α'$-corrected backgrounds, de~Sitter model building, axion physics, swampland distance tests, and compactifications in which the internal geometry varies over spacetime. Geometric data permit a computational approach to long-standing mathematical questions involving special Lagrangian submanifolds, SYZ fibrations, mirror symmetry, calibrated geometry, metric degeneration, restrictions of Ricci-flat metrics to fibers, and the search for analytic or semi-analytic structures. We present these directions as a roadmap for future work.

2605.23894 2026-05-25 quant-ph cs.IT math.IT

A Two-Branch Finite-Field Construction for Regular CSS LDPC Bases

正则CSS LDPC基矩阵的双分支有限域构造

Koki Okada, Kenta Kasai

AI总结 本文提出了一种用于构建正则CSS量子低密度奇偶校验码基矩阵的双分支有限域构造方法。该方法通过有限域上的商群余类条件,将正则性、CSS正交性和同类型四环排除等要求转化为显式条件,并通过归一化穷举搜索生成多个不同度分布的基矩阵。该构造将有限长度设计分为两个阶段,基矩阵固定度分布和初始环约束,随后通过循环提升随机化边连接,同时满足精确代数条件。实验表明,该方法构造的量子码在纠错性能上表现优异,具有较高的码距和较低的帧错误率。

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AI中文摘要

本文针对正则Calderbank-Shor-Steane (CSS)量子低密度奇偶校验基矩阵,提出了一种双分支乘法陪集构造方法。对于目标列重\(J\)和偶行重\(L\),该方法将正则性、CSS正交性和同类型4环排除归结为有限域上的显式商-陪集条件。对这些条件进行归一化穷举搜索,可生成若干\((J,L)\)对的基矩阵,因此该构造不局限于单一度分布。该构造将有限长设计分为两个阶段:基矩阵固定度分布和第一围长约束,而循环提升则通过精确代数检验随机化边连接。作为详细示例,我们将一个\((3,10)\)-正则基矩阵经历提升和解码阶段。对于该示例,选定的64倍提升得到的码,其同类型Tanner图围长至少为8,并且排除了一个指定的重量16非简并逻辑支撑轨道。最终实例是一个\([[10240,4108,\,10\le d\le32]]\) CSS码。解码方面,我们使用联合对数域置信传播以及针对小残差综合征的低复杂度确定性后处理规则,包括修复具有两个不满足校验的残差模式。帧错误率(FER)测量为该详细示例提供了有限长解码数据;在去极化概率\(p=0.058\)时,后处理FER为\(1.0 imes10^{-7}\)。

英文摘要

This paper develops a two-branch multiplicative-coset construction for regular Calderbank-Shor-Steane (CSS) quantum low-density parity-check base matrices. For a target column weight \(J\) and an even row weight \(L\), the method reduces regularity, CSS orthogonality, and same-type 4-cycle exclusion to explicit quotient-coset conditions over a finite field. A normalized exhaustive search for these conditions produces base matrices for several \((J,L)\) pairs, so the construction is not tied to a single degree distribution. The construction separates the finite-length design into two stages: the base matrix fixes the degree distribution and the first girth constraints, and a cyclic lift randomizes edge connections subject to exact algebraic checks. As a detailed example, we carry one \((3,10)\)-regular base through the lift and decoding stages. For this example, the selected 64-fold lift gives a code whose same-type Tanner graphs have girth at least eight, and it also excludes a specified weight-16 nondegenerate logical-support orbit. The resulting instance is a \([[10240,4108,\,10\le d\le32]]\) CSS code. For decoding, we use joint log-domain belief propagation together with low-complexity deterministic post-processing rules for small residual syndromes, including repairs for residual patterns with two unsatisfied checks. The frame error rate (FER) measurements provide finite-length decoding data for this detailed example; at depolarizing probability \(p=0.058\), the post-processing FER is \(1.0\times10^{-7}\).

2605.23890 2026-05-25 cs.CY cs.HC

Divergent Paths to Depolarization: Dialogue Design Determines the Prosocial Benefits of AI-Assisted Political Argumentation

去极化的分歧路径:对话设计决定AI辅助政治辩论的亲社会效益

Jianlong Zhu, Syed Muhammad Jhon Raza Naqvi, Carolin-Theresa Ziemer, Usman Naseem, Ingmar Weber

AI总结 该研究探讨了AI辅助的政治辩论对话对减少群体极化的影响,发现与自身观点一致的对话能更有效地降低情绪和观点极化。相比之下,与自身观点不一致的对话虽短期内减少共情,但长期可能提升认知特质共情。研究强调对话设计在AI介导行为干预中的关键作用。

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AI中文摘要

跨越政治分歧的论证性对话可以减少极化,但公民以可访问和结构化的方式接触对立观点的机会仍然有限。AI对话伙伴为这种开放性思维练习提供了可扩展的框架,但人机对话的格式如何影响其益处尚不清楚。在一项两阶段的在线实验中,469名美国参与者被分配与AI聊天机器人就一个有争议的政治议题争论支持或反对自己的态度。我们的实验发现,态度一致对话比态度不一致对话在即时减少情感和意见极化方面更有效。相比之下,态度不一致对话比非AI参考任务引发了更弱的认知状态共情,但在两阶段之间的两周内增加了认知特质共情,表明主动生成态度不一致论证的效果可能随时间显现。这些发现强调了对话设计是有效的AI介导行为干预的关键决定因素。

英文摘要

Argumentative dialogues across political divides can reduce polarization, yet opportunities for citizens to engage with opposing views in accessible and structured ways remain limited. AI dialogue partners offer a scalable framework for such open-mindedness exercises, but how the format of human-AI dialogues shapes their benefits remains unclear. In a two-session online experiment, 469 US participants were assigned to argue either for or against their own attitude on a contested political issue with an AI chatbot. Our experimental findings show attitude-congruent dialogues produced greater immediate reduction in both affective and opinion polarization than attitude-incongruent dialogues. By contrast, attitude-incongruent dialogues elicited weaker cognitive state empathy than the non-AI reference task but increased cognitive trait empathy in the two-week period between sessions, suggesting the effects of active generation of attitude-incongruent arguments may emerge over time. These findings highlight dialogue design as a key determinant of effective AI-mediated behavioral interventions.

2605.23884 2026-05-25 math.FA math-ph math.CA math.MP math.SP

On almost periodicity in crystalline measures

关于晶体测度的几乎周期性

Jan Mazáč, Christoph Richard, Nicolae Strungaru

AI总结 本文研究晶格测度的几乎周期性问题,探讨其作为分布的性质。作者证明了晶格测度的几乎周期性可由其平移有界性刻画,并构造了反例表明并非所有晶格测度都是平移有界的分布。通过构建特殊的晶格傅里叶特征测度,论文澄清了Meyer和Favorov提出的问题,明确了晶格测度在平移有界性方面的边界,并揭示了其在傅里叶类准晶体之外的特殊行为。

Comments 34 pages

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AI中文摘要

Meyer将晶体测度定义为满足其本身及其傅里叶变换$\widehatμ$都是局部有限支撑的纯点Radon测度的缓增分布$μ$。他猜想每个晶体测度作为缓增分布是几乎周期的。Favorov构造了一个反例,并询问晶体测度是否至少作为一般分布是几乎周期的。为了解决Favorov的问题,我们首先证明,在Radon测度、缓增分布或一般分布的任何类别中,晶体测度的几乎周期性可以用其平移有界性来刻画。然后我们构造了一个晶体傅里叶本征测度,它甚至作为分布也不是平移有界的。最后我们构造了一个晶体测度,它不是傅里叶准晶(特别地,它不是缓增的),但它是几乎周期的缓增分布,其傅里叶变换甚至是范数几乎周期测度。我们的例子完全解决了Meyer和Favorov的问题,并清晰地划定了平移有界性的类边界。它们还展示了晶体测度在傅里叶准晶类之外的异常行为。

英文摘要

Meyer defined crystalline measures as tempered distributions $μ$ such that both $μ$ and its Fourier transform $\widehatμ$ are pure-point Radon measures of locally finite support. He conjectured that every crystalline measure is almost periodic as a tempered distribution. Favorov constructed a counterexample and asked whether crystalline measures are at least almost periodic as general distributions. To resolve Favorov's question, we first show that the almost periodicity of a crystalline measure is characterised in terms of its translation boundedness, in any class of Radon measures, tempered distributions, or general distributions. We then construct a crystalline Fourier eigenmeasure that fails to be translation bounded even as a distribution. We finally construct a crystalline measure that fails to be a~Fourier quasicrystal (in particular, it fails to be slowly increasing), but it is an almost periodic tempered distribution whose Fourier transform is even a norm almost periodic measure. Our examples fully resolve the questions of Meyer and Favorov and sharply delineate the class boundary of translation boundedness. They also demonstrate the unusual behaviour of crystalline measures beyond the class of Fourier quasicrystals.

2605.23882 2026-05-25 physics.optics

Breaking order: Talbot effect with spinodal architectures

打破秩序:旋节线结构中的Talbot效应

Robin Krüger, Jeevan Rois, Martin Bech, Matias Kagias

AI总结 本文研究了在非周期性结构中是否会出现类似传统塔尔博特效应的周期性光场重构现象。通过理论分析与实验验证,作者发现受超材料启发的随机斯宾多尔结构在可见光和硬X射线波段均能表现出显著的塔尔博特效应。该成果为X射线暗场成像提供了新的光学方案,有效结合了传统光栅和扩散器的优缺点,为物质表征与操控开辟了新途径。

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AI中文摘要

Talbot效应描述了扰动传播波场中周期性图案的出现。该效应在结构相干光学(如衍射光栅)的扰动中已被充分研究。自由形态和超光学设计的出现提出了一个问题:是否也能从复杂的非周期结构中观察到类似行为?在这里,我们证明了受近期超材料设计启发的随机结构表现出强烈的类Talbot行为。通过随机旋节线结构在特定传播距离上投影波前的重现,在可见光和硬X射线波段得到了理论和实验验证。该现象的一个直接应用是用于表征人工和天然介观结构材料的X射线暗场成像。我们的工作表明,旋节线X射线光学有效弥合了暗场X射线成像中两种对立方法(即主张空间完全相干的光学(如光栅)和非相干的光学(如扩散器))之间的差距。这为探索X射线成像方法实施的新维度打开了机遇。鉴于经典Talbot效应的影响力和普遍性,我们期望我们的工作能够为表征和操控物质提供新的机会。

英文摘要

The Talbot effect describes the emergence of periodic patterns in perturbed propagating wave fields. The effect is well studied for perturbations from structurally coherent optics such as diffraction gratings. The emergence of freeform and metaoptical designs raises the question of whether comparable behavior can also be observed from complex, non-periodic structures. Here we demonstrate that stochastic structures inspired by recent metamaterial designs, display a strong Talbot-like behavior. Re-emergence of projected wavefronts through stochastic spinodal architectures at distinct propagation distances are proven theoretically and experimentally in the visible and hard X-ray regimes. A direct application of this phenomenon is X-ray dark-field imaging for characterizing artificial and natural meso-structured materials. Our work shows that spinodal X-ray optics effectively bridge the gap between the two opposing approaches in dark-field X-ray imaging that advocate for either spatially fully coherent (i.e gratings) or incoherent (i.e diffusers) optics. This opens opportunities for exploring a new dimension in the implementation of X-ray imaging methods. Given the impact and universality of the classical Talbot effect, we expect our work to enable new opportunities for characterizing and manipulating matter.

2605.23881 2026-05-25 cond-mat.quant-gas quant-ph

Time crystals in cavity-BEC systems

腔-BEC系统中的时间晶体

Jayson G. Cosme, Ludwig Mathey

AI总结 本文研究了在腔-玻色-爱因斯坦凝聚体(BEC)系统中实现的时间晶体态。通过光子发射的实时读取,该系统能够有效模拟动态现象,并克服了传统时间-of-flight成像的破坏性限制。作者回顾了三种不同类型的预测和实现的时间晶体态,并基于简化的多模模型对每种状态进行了示例分析,通过腔模关联函数和凝聚体动量模式特征对其进行了表征,为动态现象的建模和研究提供了清晰的框架和参考。

Comments 14 pages, 13 figures

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AI中文摘要

对光诱导动力学态的理解一直是科学中具有挑战性和富有成果的追求。这一追求得到了动力学现象量子模拟的支持,例如在超冷原子系统中。通常,超冷原子动力学通过飞行时间成像进行破坏性读出,限制了详细分析。然而,原子-腔系统通过腔的光子发射提供光子态的实时读出,使系统非常适合模拟动力学现象。在这里,我们综述了在腔-BEC系统中预测和实现的三种不同时间晶体态。我们基于最小少模模型为每种态给出了示例。我们通过腔模和凝聚体特征动量模的关联函数来表征时间晶体态。这支持了这些时间晶体之间的清晰区分。更一般地,这里综述的研究序列为建立动力学现象的最小模型及其表征提供了蓝图。

英文摘要

The understanding of light-induced dynamical states continues to be a challenging and fruitful pursuit of science. This pursuit is supported by quantum simulation of dynamical phenomena, e.g., in ultracold atom systems. Typically, ultracold atom dynamics are read out destructively, via time-of-flight imaging, limiting a detailed analysis. However, atom-cavity systems provide a real-time readout of the photonic state via photon emission from the cavity, making the system ideally suited for the simulation of dynamical phenomena. Here, we review three distinct time crystalline states, predicted and realized in a cavity-BEC system. We give an example for each of them, based on minimal few-mode models. We characterize the time crystalline states via correlation functions of the cavity mode, and characteristic momentum modes of the condensate. This supports a clear distinction between these time crystals. More generally, the sequence of studies reviewed here, serves as a blueprint for setting up minimal models and their characterization, for dynamical phenomena.

2605.23880 2026-05-25 hep-th gr-qc quant-ph

Not all black holes decohere quantum superpositions

并非所有黑洞都会使量子叠加退相干

Anna Biggs, Stefano Trezzi

AI总结 本文研究了近极限电荷黑洞对外部量子系统产生的退相干效应,特别分析了一个近期文献中讨论的思想实验,其中量子系统是一个处于空间叠加态的带电粒子。研究发现,当黑洞足够接近极限时,其近视界几何的量子度规涨落会导致退相干速率在晚期趋于消失,这一现象源于量子黑洞谱中的自旋诱导能量隙。尽管在能量高于该间隙时退相干速率非零,但其数值仍低于半经典预期,表明量子引力效应增强了叠加态的相干性。

Comments 26 pages, 4 figures

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AI中文摘要

我们研究了近极端带电黑洞对其外部量子系统诱导的退相干。具体来说,我们分析了文献中最近讨论的一个思想实验,其中量子系统是一个制备在空间叠加态的带电粒子。已知近极端黑洞在低温下表现出近视界几何的大量子度量涨落。我们证明,在晚期,如果黑洞足够接近极端,这些量子引力效应会使退相干速率消失。这种现象是由于量子黑洞谱中的自旋诱导能隙。对于高于能隙的能量,退相干速率变为非零,但仍相对于半经典预期被抑制,因此这些量子引力效应总是增强叠加的相干性。

英文摘要

We study the decoherence induced by near-extremal charged black holes on quantum systems in their exterior. Specifically, we analyze a thought experiment recently discussed in the literature, where the quantum system is a charged particle prepared in a spatial superposition. Near-extremal black holes are known to exhibit large quantum metric fluctuations of the near-horizon geometry at low temperatures. We show that, at late times, if the black hole is sufficiently close to extremality, these quantum gravity effects make the decoherence rate vanish. This phenomenon is due to a spin-induced energy gap in the quantum black hole spectrum. For energies above the gap, the decoherence rate becomes nonzero, but is still suppressed relative to semiclassical expectations, so these quantum gravity effects always enhance the coherence of the superposition.

2605.23877 2026-05-25 physics.flu-dyn q-bio.QM

Particle Image Velocimetry of 3D printed vascular fluidic phantom devices

3D打印血管流体仿体模型的粒子图像测速

Job van Essen, Ahmed Sharaf, Denzel Hopman, Selene Pirola, Paola Fanzio

AI总结 本研究提出了一种基于透明3D打印血管模型和粒子图像测速(PIV)技术的实验框架,用于研究微尺度脑血管中的血流动力学特性。通过构建具有正常和病理(如动脉瘤、狭窄)结构的微流体模型,结合微PIV技术测量局部速度场和壁面剪切应力,验证了该方法在捕捉关键流动特征和速度分布方面的可靠性。研究结果表明,该方法为探究微尺度脑血管血流动力学提供了稳定且有效的实验手段。

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AI中文摘要

血流动力学改变在动脉瘤和狭窄等脑血管疾病中起关键作用。然而,体内成像缺乏解决小血管中流动动力学所需的空间分辨率。本研究提出了一种实验框架,利用透明3D打印血管模型和粒子图像测速(PIV)研究微尺度血流动力学。通过增材制造制备了具有直管和病理(动脉瘤和狭窄)几何形状的光学透明微流控模型,最小直径达500微米,并使用光学显微镜进行表征。在稳态层流条件下进行流动实验,使用microPIV测量局部速度场和壁面剪切应力(WSS)。将测量速度与解析的Hagen-Poiseuille预测进行比较,平均相对误差为5%至17%。该平台可靠地捕捉了关键流动特征和速度的空间变化。总体而言,结果表明,透明3D打印血管模型结合microPIV为研究微尺度脑血管血流动力学提供了一种稳健的实验方法。

英文摘要

Altered hemodynamics play a key role in cerebrovascular diseases such as aneurysms and stenosis. However, in vivo imaging lacks the spatial resolution required to resolve flow dynamics in small vessels. This study presents an experimental framework to investigate microscale hemodynamics using transparent 3D printed vascular models and particle image velocimetry (PIV). Optically transparent microfluidic models with straight and pathological (aneurysmal and stenotic) geometries were fabricated via additive manufacturing up to a minimum diameter size of 500 microns and characterized using optical microscopy. Flow experiments were conducted under steady laminar conditions, and local velocity fields and wall shear stress (WSS) were measured using microPIV. Measured velocities have been compared with analytical Hagen Poiseuille predictions, obtaining mean relative errors of 5 to 17 percent. The platform reliably captured key flow features and spatial variations in velocity. Overall, the results demonstrate that transparent 3D printed vascular models combined with microPIV provide a robust experimental approach for studying microscale cerebrovascular hemodynamics.

2605.23876 2026-05-25 cond-mat.mtrl-sci

Photoluminescent Tetragonal Tb-doped Pb2P2O7

光致发光四方相Tb掺杂Pb2P2O7

Yong Liu, Wenhua Bi, Alla Arakcheeva, Arnaud Magrez

AI总结 本研究报道了一种新型四角晶系 Tb³⁺ 掺杂的 Pb₂P₂O₇ 材料的合成与表征。通过单晶 X 射线衍射确认了在室温下 P4₁ 和 P4₃ 对映异构体的稳定存在,归因于 Tb³⁺ 离子的引入。光学测试显示其具有绿色光致发光特性,发射光谱因晶体场效应而分裂,表明 Tb³⁺ 处于多种配位环境中。该材料在高温下表现出良好的结构稳定性,并显示出独特的温度依赖性发光行为,显示出其作为新型光致发光材料的潜力。

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AI中文摘要

在本研究中,我们报道了一种新型四方相Tb掺杂Pb2P2O7的合成与表征。单晶X射线衍射证实,由于Tb3+离子的掺入,在室温下稳定了P41和P43对映体。光学研究表明,来自Tb3+的特征5D4→7Fj(J=1-5)跃迁产生绿色光致发光,每个发射峰因晶体场效应而分裂,表明Tb3+存在于多种配位环境中。PL强度的功率依赖性遵循线性幂律行为,表明是单光子激发过程。温度相关的PL测量显示,强度在125°C之前初始增加,归因于结构缺陷的能量转移,随后在此温度以上发生热猝灭。通过高温X射线衍射(XRD)证实了高温下的结构稳定性,在约800°C熔化前未观察到相变。这些发现突出了四方相Tb掺杂Pb2P2O7作为新型光致发光材料的潜力。

英文摘要

In this study, we report the synthesis and characterization of a novel tetragonal polymorph of Tb-doped Pb2P2O7. Single-crystal X-ray diffraction confirms the stabilization of the P41 and P43 enantiomorphs at room temperature due to the incorporation of Tb3+ ions. Optical investigations reveal green photoluminescence from the characteristic 5D4 -> 7Fj (J = 1-5) transitions of Tb3+, with each emission split due to the crystal field effect, indicating the presence of Tb3+ in multiple coordination environments. The power dependence of the PL intensity follows a linear power-law behavior, suggesting a one-photon excitation process. Temperature-dependent PL measurements show an initial increase in intensity up to 125C, attributed to energy transfer from structural defects, followed by thermal quenching above this temperature. Structural stability at elevated temperatures is confirmed via high-temperature X-ray diffraction (XRD), showing no phase transitions before melting at approximately 800C. These findings highlight the potential of tetragonal Tb-doped Pb2P2O7 as a new class of photoluminescent material.

2605.23875 2026-05-25 physics.ao-ph

Atmosphere as a steam engine

大气作为蒸汽机

Anastassia Makarieva, Andrei Nefiodov

AI总结 本文将地球大气层视为一个蒸汽机,研究了水汽通过蒸发、膨胀、凝结和降水形成循环过程中的能量转换机制。通过推广克劳修斯-克拉佩龙方程,作者推导了单位降水水量的膨胀功,并考虑了抬升湿空气、凝结膨胀及不完全凝结的修正项。研究估算出全球蒸汽机功率约为4.4瓦/平方米,与大气总功率的独立估算值高度一致,揭示了凝结和降水在维持大气动力过程中的关键作用。

Comments 33 pages, 8 figures, 2 tables

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AI中文摘要

地球大气运行一个蒸汽循环,其中水蒸气从地表蒸发、膨胀、凝结并以降水形式返回。克劳修斯-克拉佩龙定律将饱和水蒸气的增量膨胀功与在对应于蒸发和凝结之间温差的卡诺效率下转换的潜热联系起来。我们将这一关系推广到凝结发生在一定高度范围内的气柱,并推导出每摩尔降水量的膨胀功。这包括将湿空气抬升到平均凝结高度相关的重力功、凝结产生的膨胀功以及不完全凝结的修正。利用GPCP v3.3降水和凝结高度的观测约束,我们估计全球蒸汽机功率为$W_v=4.4\pm0.9$ W/m2,接近独立估计的大气总功率$W=W_P+W_K\simeq4.3\pm0.6$ W/m2,后者由降水的重力功率和从MERRA-2诊断的水平压力梯度产生的动能得到。动能产生为$W_K\simeq3.2\pm0.3$ W/m2,其中至少三分之二产生于低层大气。较小的上层大气贡献(由温度相关的压力梯度主导)与洛伦兹有效位能产生相当。蒸汽机功率与大气功率之间的一致性归因于凝结和降水沉降。通过从大气气相中移除水并实现气柱质量再分布,降水维持了驱动摩擦低层大气中跨等压线流动的地表压力梯度。因此,蒸汽机框架为凝结诱导的大气动力学提供了热力学基础,并识别了与水相变相关的主要低层大气功率路径。

英文摘要

Earth's atmosphere operates a steam cycle in which water vapor evaporates from the surface, expands, condenses, and returns as precipitation. The Clausius-Clapeyron law relates the incremental expansion work of saturated water vapor to latent heat converted at a Carnot efficiency corresponding to the temperature difference between evaporation and condensation. We generalize this relation to an atmospheric column with condensation occurring over a range of heights and derive the expansion work per mole of precipitated water. This includes the gravitational work associated with lifting moist air to the mean condensation height, the expansion work generated by condensation, and a correction for incomplete condensation. Using GPCP v3.3 precipitation and observational constraints on condensation height, we estimate the global steam-engine power as $W_v=4.4\pm0.9$ W/m2, close to an independent estimate of total atmospheric power, $W=W_P+W_K\simeq4.3\pm0.6$ W/m2, obtained from the gravitational power of precipitation and kinetic energy generation by horizontal pressure gradients diagnosed from MERRA-2. Kinetic energy generation is $W_K\simeq3.2\pm0.3$ W/m2, of which at least two thirds is generated in the lower atmosphere. The smaller upper-atmospheric contribution, dominated by temperature-related pressure gradients, is comparable to Lorenz available potential energy generation. The agreement between steam-engine and atmospheric power is linked to condensation and precipitation fallout. By removing water from the atmospheric gas phase and enabling column-mass redistribution, precipitation maintains surface pressure gradients that drive cross-isobaric flow in the frictional lower atmosphere. The steam-engine framework thus provides a thermodynamic basis for condensation-induced atmospheric dynamics and identifies a major lower-atmospheric power pathway associated with water phase transitions.

2605.23873 2026-05-25 quant-ph cond-mat.quant-gas cond-mat.stat-mech cond-mat.str-el

Coherent dynamics in chaotic spin chains via interference-protected subspaces

混沌自旋链中通过干涉保护子空间的相干动力学

Aron Kerschbaumer, Jean-Yves Desaules, Maksym Serbyn

AI总结 该研究探讨了混沌自旋链中通过干涉保护子空间实现的相干动力学现象。作者提出了一类具有结构化子空间的自旋-1/2链模型,能够在高能量密度下支持非热化现象,如疤痕态、手性传播准粒子和近似拓扑边缘态。研究通过破坏性干涉保护的子空间解释了这些现象,并建立了定量泄漏理论,预测了哪些态能够保持相干性,同时提出了增强稳定性的方法,拓展了混沌系统中弱遍历性破坏的范围。

Comments 8+4 pages, 6+1 figures

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AI中文摘要

一般量子多体系统预期会热化,在局域观测量弛豫到平衡值的同时扰乱初始相干性。弱遍历性破缺通常与均匀态的量子多体疤痕相关,提供了具有长寿命相干性的罕见例外。我们引入一族局域自旋-1/2链,其具有一个结构化子空间,该子空间承载更广泛的非热现象,如疤痕、手性传播准粒子或近似拓扑边缘模。这些发生在高能量密度下的非热现象可以通过受相消干涉保护的结构化子空间来理解。我们发展了一种定量泄漏理论,预测哪些态保持相干性,并提出了通过诱导补子空间中的快速振荡来提高稳定性的方法。我们的框架连接了渐近疤痕、量子笼和母哈密顿量构造,并表明混沌系统中的弱遍历性破缺远不止于均匀初始态的复兴。

英文摘要

Generic quantum many-body systems are expected to thermalize, scrambling initial coherence while local observables relax to equilibrium values. Weak ergodicity breaking, often associated with quantum many-body scarring of homogeneous states, provides rare exceptions with long-lived coherence. We introduce a family of local spin-1/2 chains with a structured subspace that hosts a much broader range of nonthermal phenomena, such as scars, chirally propagating quasiparticles or approximate topological edge modes. These nonthermal phenomena happening at high energy densities can be understood via structured subspaces that are protected by destructive interference. We develop a quantitative leakage theory predicting which states retain coherence and suggest ways to improve the stability by inducing fast oscillations in the complement subspace. Our framework connects asymptotic scars, quantum cages, and parent-Hamiltonian constructions, and shows that weak ergodicity breaking in chaotic systems extends well beyond revivals of homogeneous initial states.

2605.23870 2026-05-25 physics.atom-ph physics.comp-ph

Vapor-Cell-Induced Uncertainty in Rydberg Atom Measurements via the Electric-Field Volume-Integral-Equation Method

基于电场体积积分方程法的蒸气室在里德伯原子测量中的不确定性分析

Martin Stumpf, William J. Watterson, Rajavardhan Talashila, Matt T. Simons, Alexandra Artusio-Glimpse, Lawrence Carslake, Tian Hong Loh, Christopher L. Holloway

AI总结 本研究利用体积积分方程方法分析了蒸汽池对基于里德伯原子传感器的电场测量所产生的电磁散射效应。通过计算蒸汽池内网格点上的电场分布,该方法在优化计算和统计不确定性分析中表现出较高的效率。研究比较了由蒸汽池引起的不确定性(如玻璃相对介电常数的不确定性或驻波形成)与原子光谱测量引起的不确定性(如原子偶极矩的不确定性),发现当蒸汽池尺寸小于半个波长时,玻璃相对介电常数的不确定性是主要来源,总不确定性约为3.5%,接近国家计量机构传统方法的最优水平,精确测量介电常数有望将不确定性降低至1%以下。

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AI中文摘要

借助体积积分方程法分析了蒸气室对基于里德伯原子的传感器进行电场测量时的电磁散射效应。与测量类似,该计算方法确定了蒸气室内网格点上的电场。其相对较高的计算效率使其适用于优化程序和统计不确定性研究。我们应用该方法比较了由于蒸气室存在引起的不确定性贡献,例如玻璃相对介电常数的不确定性或室内驻波形成,与原子光谱测量引起的不确定性,例如原子偶极矩的不确定性。对于尺寸小于半波长的蒸气室,主要不确定性来源来自玻璃相对介电常数的不确定性,导致总不确定性约为3.5%——与国家计量研究所使用传统场生成方法获得的最佳不确定性相当。精确的介电常数测量有可能进一步将测量不确定性降低到<1%。

英文摘要

Electromagnetic scattering effects of a vapor cell on electric-field measurements using Rydberg atom-based sensors are analyzed with the aid of the volume integral equation method. In a manner similar to measurement, this computational approach determines the electric field over grid points within the vapor cell. Its relatively high computational efficiency makes it suitable for use in optimization routines and statistical uncertainty studies. We apply this method to compare uncertainty contributions arising due to the presence of the vapor cell, such as uncertainty in the glass relative permittivity or standing wave formation inside the cell, to those arising from the atomic spectroscopic measurement, such as uncertainty in the atomic dipole moment. For vapor cell dimensions less than half a wavelength, the dominant uncertainty source arises from uncertainty in the glass relative permittivity, resulting in a total uncertainty of $\sim$3.5\% -- comparable to the best uncertainties obtained with traditional field generation methods at national metrology institutes. Precise permittivity measurements have the potential to further reduce measurement uncertainty to $<1$\%.

2605.23869 2026-05-25 physics.flu-dyn

Soft Mobility Theory

软体运动理论

Christophe Eloy

AI总结 该研究提出了“软体运动理论”,用于预测可变形物体在粘性流体中的运动与形变,解决了从微生物运动到软体微型机器人等广泛问题。通过引入虚拟功率原理和洛伦兹互易定理,研究建立了依赖于物体形变的广义坐标常微分方程,扩展了经典刚体运动理论。该理论应用于由弹性弹簧连接的相互作用球体系统,并通过梯度下降方法实现了高效的逆向设计,展示了在静止流和剪切流中优化软体游动器和设计软体“冲浪者”的应用。

Comments 22 pages, 11 figures

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AI中文摘要

预测可变形体在粘性流中的运动和变形是微生物运动到软体微型机器人等问题的核心,但现有框架要么针对特定问题,要么不适合逆设计。我们提出软体运动理论:将虚功率原理和洛伦兹互易定理应用于背景斯托克斯流中的超弹性体,得到关于物体广义坐标的依赖于构型的常微分方程。该软体运动方程扩展了经典刚体运动理论,其中运动、弹性、体力、流耦合张量均显式依赖于瞬时变形。我们将该框架特化到由弹性弹簧连接的水动力学相互作用球体组装体,使用Rotne-Prager-Yamakawa近似计算运动张量,并在静止和剪切流中的刚体和柔性体经典问题上进行验证。开源的JAX实现使整个模拟可端到端微分,从而实现高效的基于梯度的逆设计:作为概念验证,我们恢复了三球游泳者的渐近最优解,并设计了一个软体趋旋性“冲浪者”,该冲浪者利用被动变形在泰勒-格林流中比其刚性对应物上升更快。

英文摘要

Predicting how a deformable body moves and deforms in a viscous flow underlies problems ranging from microorganism locomotion to soft microrobotics, yet existing frameworks are either problem-specific or ill-suited to inverse design. We propose the soft mobility theory: applying the principle of virtual power and the Lorentz reciprocal theorem to a hyperelastic body in a background Stokes flow yields a configuration-dependent ordinary differential equation for the generalized coordinates of the body. This soft mobility equation extends classical rigid-body mobility theory in that the mobility, elastic, body-force, and flow-coupling tensors all depend explicitly on the instantaneous deformation. We specialize the framework to assemblies of hydrodynamically interacting spheres connected by elastic springs, using the Rotne-Prager-Yamakawa approximation to compute the mobility, and validate it on canonical problems spanning rigid and flexible bodies in quiescent and shear flows. An open-source JAX implementation makes entire simulations end-to-end differentiable. This allows efficient gradient-based inverse design: as proofs of concept, we recover the asymptotic optimum of a three-sphere swimmer and design a soft gyrotactic "surfer" that exploits passive deformation to ascend faster than its rigid counterpart in a Taylor-Green flow.

2605.23866 2026-05-25 math.MG cs.DM

Optimal Vector Balancing for Zonotopes

Zonotopes的最优向量平衡

Victor Reis

AI总结 本文研究了zonotope(一种由立方体线性映射得到的几何对象)的最优向量平衡问题。作者证明了存在一个通用常数 $C$,使得对于任意zonotope $Z \subset \mathbb{R}^d$ 和其中的向量 $v_1, \dots, v_n$,总存在符号 $x_1, \dots, x_n \in \{-1, 1\}$,使得 $\sum_{i=1}^n x_i v_i$ 落在 $C\sqrt{d} Z$ 内。该结果解决了Schechtman于2002年提出的问题,并推广了Spencer的六标准偏差定理。

Comments 24 pages

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AI中文摘要

一个zonotope是立方体$[-1,1]^m$(对某个$m \in \mathbb{N}$)的线性像。我们证明存在一个通用常数$C$,使得对于每个zonotope $Z\subset \mathbb{R}^d$和向量$v_1,\dots,v_n\in Z$,存在符号$x_1,\dots,x_n\in\{-1,1\}$满足\[ \sum_{i=1}^n x_i v_i \in C\sqrt d\, Z. \]这解决了Schechtman在2002年提出的一个问题,并推广了Spencer的六标准差定理,后者对应于$Z=[-1,1]^d$的情况。

英文摘要

A zonotope is a linear image of the cube $[-1,1]^m$ for some $m \in \mathbb{N}$. We show that there is a universal constant $C$ such that, for every zonotope $Z\subset \mathbb{R}^d$ and vectors $v_1,\dots,v_n\in Z$, there are signs $x_1,\dots,x_n\in\{-1,1\}$ with \[ \sum_{i=1}^n x_i v_i \in C\sqrt d\, Z. \] This resolves a 2002 question of Schechtman and generalizes Spencer's six standard deviations theorem, which corresponds to the case $Z=[-1,1]^d$.

2605.23865 2026-05-25 math.RA

Images of polynomials with involution on $2\times 2$ matrices

带有对合的 $2\times 2$ 矩阵上多项式的像

Lucio Centrone, Thiago Castilho de Mello

AI总结 本文研究了在配备第一类对合的 $2\times 2$ 矩阵代数上,多线性 $*$-多项式的像集结构。作者针对实数域上的转置对合和二次闭域或实数域上的辛对合,分别分析了像集的性质,证明其要么是真子空间,要么包含矩阵空间的基,或总是构成一个向量空间。作为副产品,作者完善了 Brešar 和 Klep 关于有限维中心单代数上 $*$-多项式像集线性包的定理,并对维度为 4 和 16 的情况进行了补充,同时分类了特征为零的域上 $M_4(\mathbb{F})$ 的李斜理想。

Comments 17 pages

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AI中文摘要

设 $\mathbb{F}$ 是一个域,$M_2(\mathbb{F})$ 是 $2\times 2$ 矩阵的代数,并赋予第一类对合。我们研究在 $M_2(\mathbb{F})$ 上评估的多重线性 $*$-多项式的像。对于 $\mathbb{R}$ 上的转置对合,我们证明像要么是真向量子空间,要么包含 $M_2(\mathbb{R})$ 的一组基。对于二次闭域或 $\mathbb{R}$ 上的辛对合,我们证明像总是一个向量空间,即 $\{0\}$、$\mathbb{F}$、$sl_2(\mathbb{F})$ 或 $M_2(\mathbb{F})$ 之一。作为副产品,我们完善了 Brešar 和 Klep 的一个定理,该定理描述了具有第一类对合的有限维中心单代数上 $*$-多项式像的线性张成。他们的结果排除了维数为 4 和 16 的代数;我们解决了这两种情况,将描述扩展到所有大于 1 的维数(在 $\mathbb{R}$ 上对于转置对合,在二次闭域或 $\mathbb{R}$ 上对于辛对合)。我们还分类了特征零域上 $M_4(\mathbb{F})$ 的所有李斜理想。

英文摘要

Let $\mathbb{F}$ be a field and let $M_2(\mathbb{F})$ be the algebra of $2\times 2$ matrices endowed with an involution of the first kind. We study the image of multilinear $*$-polynomials evaluated on $M_2(\mathbb{F})$. For the transpose involution over $\mathbb{R}$, we show that the image is either a proper vector subspace or contains a basis of $M_2(\mathbb{R})$. For the symplectic involution over quadratically closed fields or over $\mathbb{R}$, we prove that the image is always a vector space, namely one of $\{0\}$, $\mathbb{F}$, $sl_2(\mathbb{F})$ or $M_2(\mathbb{F})$. As a byproduct, we complete a theorem of Brešar and Klep describing the linear span of the image of a $*$-polynomial on finite dimensional central simple algebras with involution of the first kind. Their result excluded algebras of dimensions 4 and 16; we settle both cases, extending the description to all dimensions greater than 1 (over $\mathbb{R}$ for the transpose involution, and over quadratically closed fields or $\mathbb{R}$ for the symplectic involution). We also classify all Lie skew-ideals of $M_4(\mathbb{F})$ over fields of characteristic zero.

2605.23864 2026-05-25 math.OC cs.SY eess.SY

Harnessing Individual Motivation for Collective Efficiency: A Mechanism-Driven Distributed Optimization Method

利用个体动机实现集体效率:一种机制驱动的分布式优化方法

Dongwei Xie, Xuhao Wang, Yujie Tang, Jie Song

AI总结 在涉及多智能体协作决策的工业场景中,由于个体信息难以集中获取以及个体利益与全局性能之间的冲突,传统的集中式决策可能不可行。本文提出了一种机制驱动的分布式优化方法,通过设计激励机制引导各参与者在以自我利益驱动的前提下进行协作。该方法针对具有耦合目标函数和耦合约束的优化问题,设计了相应的分布式算法并提供了收敛性保证,同时引入两种激励机制以确保参与者的协作意愿,形成闭环反馈系统,实验结果验证了算法和机制的有效性。

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AI中文摘要

在涉及多智能体集体决策的工业场景中,由于对个体局部信息的访问受限,集中式决策可能不可行,而参与者自利与全局性能之间的冲突也可能阻碍协作式分布式决策。本文提出一种机制驱动的分布式决策方法,其中采用并设计激励措施,以激励参与者以分布式方式协作,即使每个参与者的决策主要受自利驱动。针对具有耦合目标函数和耦合约束的优化问题,我们设计了一种针对此类问题定制的分布式优化算法,并为其收敛性提供了保证。此外,我们设计了两种激励机制:影子定价机制和Vickrey-Clarke-Groves机制,并证明了在这些机制下参与者愿意参与分布式协作。该机制驱动分布式算法的执行,而分布式计算的最优结果指导机制中激励的确定,两者相互关联形成闭环。最后,数值实验说明了所提算法和机制的有效性。

英文摘要

In industrial scenarios involving multi-agent collective decision-making, centralized decision-making may not be admissible due to restrictive access to individual local information, while the conflicts between participants' self-interest and global performance may also impede collaborative distributed decision-making. This paper proposes a mechanism-driven distributed decision-making method, wherein incentives are employed and designed to motivate participants to collaborate in a distributed fashion even though each participant's decision is driven primarily by self-interest. Focusing on optimization problems with coupled objective functions and coupled constraints, we design a distributed optimization algorithm tailored for this class of problems and provide guarantees for its convergence. Furthermore, we design two incentive mechanisms, the shadow pricing mechanism and the Vickrey-Clarke-Groves mechanism, and demonstrate that participants are willing to engage in distributed collaboration under these mechanisms. The mechanism drives the execution of the distributed algorithm, and the optimal result of distributed computation guides the determination of incentives in the mechanism, both of which are interrelated to form a closed loop. Finally, numerical experiments illustrate the effectiveness of the proposed algorithm and mechanisms.

2605.23860 2026-05-25 physics.ins-det hep-ex

TCAD + Allpi$\text{x}^2$ Simulation study of MALTA2, a Depleted Monolithic Active Pixel Sensor for future tracking

TCAD + Allpi$\text{x}^2$ 对 MALTA2 的仿真研究:一种用于未来跟踪的耗尽型单片有源像素传感器

L. Li, P. Behera, D. V. Berlea, D. Bortoletto, C. Buttar, T. Chembakan, V. Dao, G. Dash, Y. Enari, L. Fasselt, S. Haberl, T. Inada, F. K. Isik, C. Issever, X. Li, Y. Okazaki, H. Pernegger, P. Riedler, W. Snoeys, C. A Solans Sanchez, A. Swoboda, I. Turk Cakir, M. van Rijnbach, A. Vijay, S. Worm

AI总结 本文提出了一种结合TCAD和Allpix²的混合仿真框架,用于研究未来跟踪应用中耗尽型单片活性像素传感器MALTA2的性能。通过TCAD进行三维建模和瞬态仿真,获得掺杂分布和电场信息,并输入Allpix²进行高统计量的蒙特卡洛仿真,分析其在单探测器和全望远镜模式下的表现。研究发现传感器的探测效率和簇尺寸强烈依赖于传感器表面N型覆盖层的掺杂浓度,并通过与实验数据对比优化了该浓度。仿真与测量结果在活性区域深度方面达成良好一致,偏差仅为2%,验证了该框架在传感器研究中的通用性和有效性。

Comments 21 pages, 15 figures

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AI中文摘要

在这项工作中,提出了一个结合 TCAD 和 Allpi$\text{x}^2$ 的混合仿真框架,以研究 MALTA2(一种为未来跟踪设计的耗尽型单片有源像素传感器)的传感器特性。研究从 TCAD 中的三维建模和瞬态仿真开始,采用通用掺杂分布和简单阱结构。提取得到的掺杂分布和电场被输入到 Allpi$\text{x}^2$ 中,用于在仅被测器件模式和全望远镜模式下进行高统计蒙特卡罗模拟。 模拟揭示了传感器性能(特别是探测效率和簇大小)对传感器表面 N 型覆盖层掺杂浓度的强烈依赖性。然后通过将模拟与测量数据进行比较来优化掺杂浓度。使用掠射角方法在模拟和测量中估计了 MALTA2 传感器耗尽区的活性深度,该方法将传感器相对于束流放置在不同的倾角下,覆盖从 0 到 60 度的角度。在最佳掺杂浓度下,活性深度与测量值吻合良好,在 450 $\text{e}^-$ 阈值下偏差为 2%。因此,该框架为传感器研究提供了一个通用工具包,无需专有信息。

英文摘要

In this work, a hybrid simulation framework combining TCAD and Allpi$\text{x}^2$ is presented to investigate the sensor properties of MALTA2, a depleted monolithic active pixel sensor designed for future tracking. The study starts from 3D modeling and transient simulations in TCAD, with generic doping profiles and simple well structures. The resulting doping profiles and electric field are extracted and fed into Allpi$\text{x}^2$ for high-statistics Monte Carlo simulations in both DUT-only and full-telescope mode. Simulations reveal a strong dependence of sensor performance, specifically the detection efficiency and cluster size, on the doping concentration of the N-type blanket at the sensor surface. The doping concentration is then optimized by comparing simulations with measurement data. The active depth of the depleted region of the MALTA2 sensor is estimated in both simulations and measurements using a grazing angle method, in which the sensor is positioned at various inclinations relative to the beam, covering angles from 0 to 60 degrees. Excellent agreement on active depth is obtained with the optimal doping concentration, showing a deviation of 2\% from the measured value at a threshold of 450\,$\text{e}^-$. Consequently, the framework offers a generic toolkit for sensor studies without requiring proprietary information.

2605.23859 2026-05-25 eess.AS

Natural Yet Challenging to Detect: Robust In-the-Wild TTS through EMA and Dual-Scoring Prompt Selection -- Submission for WildSpoof 2026 TTS Track

自然但难以检测:通过EMA和双评分提示选择实现鲁棒的野外TTS——WildSpoof 2026 TTS赛道提交

Renhe Sun, Jiayi Zhou, Haolin He, Yueying Feng, Jian Liu

AI总结 本文介绍了针对WildSpoof 2026 TTS赛道的提交方案F5-TTS-DPS,旨在提升使用真实场景数据生成文本到语音的鲁棒性。该模型基于F5-TTS架构,引入指数移动平均(EMA)以稳定训练过程,并结合大型语言模型和大型音频语言模型进行双评分提示选择,有效提升合成语音的质量与自然度。实验结果表明,F5-TTS-DPS在多个评估指标上表现优异,尤其在欺骗检测中展现出最强的抗检测能力,验证了其在生成自然且难以被识别的语音方面的有效性。

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AI中文摘要

在这份技术报告中,我们描述了针对WildSpoof挑战TTS赛道(使用野外数据的文本到语音)的提交方案。我们提出了F5-TTS-DPS,一个基于F5-TTS架构的模型。我们的方法将指数移动平均(EMA)集成到监督微调中,以稳定训练并提高泛化能力。为了增强合成保真度,我们利用大语言模型(LLMs)和大音频语言模型(LALMs)进行双评分提示选择,过滤参考音频和文本提示以确保质量,同时解决噪声数据集中的对齐问题。实验评估表明,F5-TTS-DPS在开发集上取得了强劲性能,UTMOS为3.20,说话人相似度为0.51。更重要的是,我们的模型在所有提交中,针对三种先进SASV系统取得了最佳a-DCF分数,分别为0.1582、0.5233和0.2562,表明我们的合成语音最难检测,并展现出最高程度的自然度和真实性。结合具有竞争力的WER性能,这些结果验证了我们的方法在生成具有强欺骗能力的自然语音方面的有效性。

英文摘要

In this technical report, we describe our submission for the WildSpoof Challenge TTS Track: Text-to-Speech with In-the-Wild Data. We introduce F5-TTS-DPS, a model built upon the F5-TTS architecture. Our approach integrates Exponential Moving Average (EMA) into supervised fine-tuning to stabilize training and improve generalization. To enhance synthesis fidelity, we leverage large language models (LLMs) and large audio language models (LALMs) for dual-scoring prompt selection, filtering reference audio and text prompts to ensure quality while addressing alignment issues in noisy datasets. Experimental evaluation demonstrates that F5-TTS-DPS achieves strong performance with UTMOS of 3.20 and speaker similarity of 0.51 on the development set. More importantly, our model achieves the best a-DCF scores of 0.1582, 0.5233, and 0.2562 across three advanced SASV systems among all submissions, indicating our synthesized speech is the most difficult to detect and exhibits the highest degree of naturalness and authenticity. Combined with competitive WER performance, these results validate the effectiveness of our approach in generating natural-sounding speech with strong spoofing capabilities.

2605.23858 2026-05-25 stat.AP

Anticipating Continued Global Fertility Decline via Neural Forecasting

通过神经预测预见持续的全球生育率下降

Daniel Ciganda, Facundo Morini, Francisco Piriz, Henrik-Alexander Schubert, Ugofilippo Basellini, Mikko Myrskylä

AI总结 本文研究了全球生育率持续下降的趋势,并引入了一个基于循环神经网络的预测框架NeuralTFR,用于评估各国生育率未来的发展路径。该模型通过整合196个国家和地区的历史生育数据,学习人口动态并生成预测区间,表现出比现有方法更优的预测精度和不确定性校准能力。研究发现,与联合国的BayesTFR模型相比,NeuralTFR预测到2040年全球将面临更广泛的低生育率状况,表明短期内生育率稳定的可能性较低。

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AI中文摘要

向低和超低生育率的加速转变加剧了争论:目前正在经历快速下降的国家是趋于稳定还是进入更持久的低生育率体制?现有预测系统对此给出了不同答案,因为它们嵌入了关于恢复和外部驱动因素作用的不同假设。为了在这场辩论中提供经验基准,我们引入了NeuralTFR,一个基于循环神经网络的内生全球预测框架。利用来自196个国家和地区的协调历史生育率序列面板,该模型汇集跨国信息以学习人口惯性,并通过多分位数回归生成经验预测区间。在保留期(2009-2023年)的评估中,NeuralTFR的点预测误差低于Naive Drift基线和联合国贝叶斯层次模型BayesTFR,同时保持竞争性的不确定性校准。在到2040年的前瞻预测中,NeuralTFR指出低和极低生育率的暴露范围比BayesTFR更广,表明对近期稳定性的支持较弱,但仍未达到全球疾病负担项目预测的最严重下降路径。

英文摘要

The accelerating shift toward low and ultra-low fertility has intensified the debate over whether countries now undergoing rapid decline are approaching stabilization or entering a more persistent low-fertility regime. Existing projection systems answer that question differently because they embed different assumptions about recovery and about the role of external drivers. To provide an empirical benchmark in this debate, we introduce NeuralTFR, an endogenous global forecasting framework based on a recurrent neural network. Drawing on a harmonized panel of historical fertility series from 196 countries and territories, the model pools cross-country information to learn demographic momentum and generate empirical prediction intervals via multi-quantile regression. Evaluated on a held-out period (2009--2023), NeuralTFR achieves lower point-forecast errors than a Naive Drift baseline and BayesTFR, the United Nations' Bayesian Hierarchical Model, while maintaining competitive uncertainty calibration. In forward projections to 2040, NeuralTFR points to broader exposure to low and very low fertility than BayesTFR, suggesting weaker support for near-term stabilization while still falling short of the most severe decline paths predicted by the Global Burden of Disease project.

2605.23855 2026-05-25 cond-mat.mtrl-sci

Phase-dependent electronic structure of two-dimensional Ag layers at the graphene/SiC interface

石墨烯/SiC界面二维银层的相依赖电子结构

Sawani Datta, Boyang Zheng, Arpit Jain, Kathrin Küster, Joshua A. Robinson, Vincent H. Crespi, Ulrich Starke

AI总结 本研究探讨了在石墨烯/SiC界面处插入的二维银层的相依赖性电子结构。通过原位超高真空制备方法,获得了与SiC晶格旋转30度的高密度Ag$_{(2)}$相,并利用低能电子衍射和角分辨光电子能谱揭示了其更丰富的能带结构。理论计算表明,Ag$_{(2)}$的能带结构更适合展开到SiC原胞,且其对石墨烯层的电荷载流子密度和电荷-等离子体相互作用具有显著影响,显示出界面电子性质的调控潜力。

Comments 13 pages, 7 figures, Supplementary information is in the ancillary file

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AI中文摘要

石墨烯/SiC界面的插层提供了一种可控途径来稳定原子级薄层,其性质与块体对应物不同。在该平台中,插层相的结构和稳定性敏感地依赖于起始衬底的缺陷景观。对于石墨烯/SiC界面插层的二维银,已观察到两个相:一个与SiC晶格外延的相Ag$_{(1)}$,可通过超高真空条件下的常规插层方法轻松获得并得到广泛表征;另一个更密集堆积的相称为Ag$_{(2)}$,此前尚未被充分探索。本文报道了一种原位超高真空制备方法,用于在石墨烯/SiC界面制备第二种插层相;该相先前是通过高压限制异质外延制备的。低能电子衍射显示,Ag$_{(2)}$相对于SiC晶格旋转30度并形成超胞,而Ag$_{(1)}$与SiC呈$(1\times 1)$外延关系。高分辨率角分辨光电子能谱揭示Ag$_{(2)}$比Ag$_{(1)}$具有更丰富的能带色散。在密度泛函理论计算中,通过定义展开熵,以量化方式发现Ag$_{(2)}$的能带结构更适合展开到SiC原胞,且展开后的能带色散与实验数据高度一致。我们进一步表明,不同的插层Ag相以不同方式调控上方准自由站立石墨烯层的电子性质:与Ag$_{(1)}$相比,Ag$_{(2)}$产生约1.75倍的更高载流子密度,并改变石墨烯层的电荷-等离子体相互作用,表明界面有效屏蔽发生变化。

英文摘要

Intercalation at the graphene/SiC interface provides a controlled route to stabilize atomically thin layers with properties distinct from their bulk counterparts. In this platform, the structure and stability of the intercalated phase depend sensitively on the defect landscape of the starting substrate. For intercalated two-dimensional silver at the graphene/SiC interface, two phases have been observed: a phase epitaxial to the SiC lattice, Ag$_{(1)}$, readily obtained following the conventional intercalation method under ultra-high-vacuum conditions and extensively characterized, and a more densely packed phase, called Ag$_{(2)}$, which has remained largely unexplored. Here we report an in situ ultra-high-vacuum preparation method of the second phase intercalated at the graphene/SiC interface; this phase previously was prepared via high-pressure confinement heteroepitaxy. Low-energy electron diffraction shows that Ag$_{(2)}$ is rotated by 30 degree relative to the SiC lattice and forms supercells, in contrast to the $(1\times 1)$ epitaxial relation of Ag$_{(1)}$ with SiC. High-resolution angle-resolved photoemission spectroscopy reveals a more rich Ag$_{(2)}$ band dispersion compared to the Ag$_{(1)}$. In density functional theory calculations, by defining the unfolding entropy which, in a quantified way, finds that the band structure of Ag$_{(2)}$ is more suitable to be unfolded to the SiC primitive cell, and the resulting unfolded band dispersion is in great agreement with the experimental data. We further show that the different intercalated Ag phases tune the electronic properties of the overlying quasi-free-standing graphene layer differently: compared with Ag$_{(1)}$, Ag$_{(2)}$ yields an $\sim$1.75 times higher charge carrier density and modifies the charge-plasmon interaction of the graphene layer, indicating a change in effective screening at the interface.