arXivDaily arXiv每日学术速递 周一至周五更新
全部学科分类 2084
专题追踪
2604.15939 2026-05-27 astro-ph.SR astro-ph.GA

Revisiting the Galactic age-metallicity relation from wide white dwarf-main-sequence binaries

从宽距白矮星-主序星双星重新审视银河系年龄-金属丰度关系

Alberto Rebassa-Mansergas, Iset Tejero-Gómez, Roberto Raddi

AI总结 利用Gaia DR3数据构建宽距白矮星-主序星双星样本,通过白矮星测光年龄和主序星[Fe/H]丰度,发现银河系盘年龄-金属丰度关系存在大弥散,支持径向迁移等机制导致的内在散射。

Comments Accepted for publication in A&A

Journal ref A&A 709, A250 (2026)

详情
AI中文摘要

年龄-金属丰度关系(AMR)是理解银河系化学演化的基本观测约束。作为可靠的宇宙计时器,与主序星伴星组成的双星系统中的白矮星(WD+MS双星)为研究这一关系提供了极好的实验室,因为两个组分预期是同年龄的。我们利用Gaia任务第三次数据发布的数据,构建了一个宽距分离的WD+MS双星样本,以研究银河系盘的AMR。该样本通过两个组分的光度测量和视差来识别。白矮星年龄通过在最先进的白矮星演化序列中插值其Gaia绝对G星等和BP-RP颜色得到。我们从文献中汇编了主序星伴星的公开[Fe/H]丰度,并使用不同的统计方法组合它们,以获得每个系统的代表性金属丰度值。我们从几个使用独立[Fe/H]丰度测量的WD+MS子样本中推导出AMR,并一致地发现所有年龄的[Fe/H]都存在大的弥散。这一行为与先前基于WD+MS双星和孤立恒星样本的AMR测定结果一致。我们的结果加强了观测证据,即银河系盘中的AMR表现出显著的内在散射,可能反映了多种机制的综合效应,如径向迁移、不均匀化学增丰和恒星形成历史的变化。

英文摘要

The age-metallicity relation (AMR) is a fundamental observational constraint for understanding the chemical evolution of the Galaxy. As reliable cosmochronometers, white dwarfs in binary systems with main sequence companions (WD+MS binaries) provide excellent laboratories to study this relation, since both components are expected to be coeval. We construct a sample of widely separated WD+MS binaries using data from the third data release of the Gaia mission in order to investigate the AMR of the Galactic disk. The sample is identified using photometric measurements and parallaxes of both components. White dwarf ages are derived by interpolating their Gaia absolute G magnitudes and BP-RP colours within state-of-the art white dwarf evolutionary sequences. We compile publicly available [Fe/H] abundances for the main sequence companions from the literature and combine them using different statistical approaches to obtain representative metallicity values for each system. We derive the AMR from several sub-samples of WD+MS that use independent measurements of [Fe/H] abundances and consistently find a large dispersion in [Fe/H] at all ages. This behaviour agrees with previous determinations of the AMR based on both WD+MS binaries and samples of isolated stars. Our results reinforce the observational evidence that the AMR in the Galactic disk exhibits substantial intrinsic scatter, likely reflecting the combined effects of multiple mechanisms such as radial migration, inhomogeneous chemical enrichment, and variations in the star formation history.

2604.15428 2026-05-27 astro-ph.SR astro-ph.EP

The CARMENES search for exoplanets around M dwarfs. A homogeneous catalogue of projected rotational velocities accounting for limb-darkening

CARMENES 搜寻 M 矮星周围系外行星:考虑临边昏暗的投影自转速度均匀星表

R. Varas, G. Morello, M. Zechmeister, P. J. Amado, F. J. Pozuelos, J. A. Caballero, A. Claret, C. Cifuentes, R. Morales, A. Quirrenbach, A. Reiners, I. Ribas, V. J. S. Béjar, M. Cortés-Contreras, A. P. Hatzes, Th. Henning, I. Hermelo, H. L. Ruh, A. Schweitzer, H. M. Tabernero, M. R. Zapatero Osorio

AI总结 提出一种结合真实临边昏暗模型的过采样卷积方法,从 CARMENES 光谱精确测量 M 矮星的投影自转速度,构建了目前最大的均匀星表,测量精度显著优于文献。

Comments 12 pages, 16 figures, 4 tables. Accepted for publication in A&A

Journal ref A&A 709, A244 (2026)

详情
AI中文摘要

恒星自转与年龄和磁活动密切相关。通过陀螺年代学,它提供了一种估计恒星年龄和追踪行星系统演化的手段,并且对于约束和校正恒星活动效应以实现稳健的系外行星探测和表征也至关重要。CARMENES 是一个双通道高分辨率(R > 80000)光谱仪,在利用视向速度技术探测 M 矮星周围的系外行星方面非常成功,同时它还能通过谱线展宽精确测量投影自转速度(vsini)。我们提出了一种过采样卷积方法,结合真实的临边昏暗模型,通过将观测光谱与模板星光谱进行比较,从 CARMENES 光谱中确定 vsini。利用覆盖有效温度 2500-4000 K 和投影自转速度高达 50 km/s 的高分辨率合成光谱,评估了该方法相对于文献中现有方法的优势。应用于 392 颗由 CARMENES 观测的 M 矮星,我们的方法得到的 vsini 测量值(或 2 km/s 的上限)的中位相对不确定度为 6.8%,远小于文献中报告的 15.4%。这项工作提供了最大的 M 矮星 vsini 测量均匀星表,包括多个目标显著更新的值,以及 36 个新目标。

英文摘要

Stellar rotation is closely linked to both age and magnetic activity. Through gyrochronology, it provides a means to estimate stellar ages and trace the evolution of planetary systems, and it is also crucial to constrain and correct stellar activity effects for robust exoplanet detection and characterisation. CARMENES is a dual-channel, high-resolution (R > 80000) spectrograph that has been highly successful in detecting exoplanets around M-dwarf stars using the radial-velocity technique, and it also enables precise measurements of the projected rotational velocity (vsini) from spectral line broadening. We present an oversampled convolution method incorporating a realistic limb-darkening model to determine vsini from CARMENES spectra by comparing observed spectra with that of a template star. The advantages over existing methods in the literature have been assessed using high-resolution synthetic spectra spanning effective temperatures of 2500-4000 K and projected rotational velocities of up to 50 km/s. Applied to 392 M dwarfs observed with CARMENES, our method yields vsini measurements (or upper limits at 2 km/s) with a median relative uncertainty of 6.8%, substantially smaller than the 15.4% reported in the literature. This work provides the largest uniform catalogue of vsini measurements for M dwarfs, including significantly updated values for several targets, along with 36 new targets.

2604.07073 2026-05-27 cs.SE

Assessing REST API Test Generation Strategies with Log Coverage

使用日志覆盖率评估REST API测试生成策略

Nana Reinikainen, Mika Mäntylä, Yuqing Wang

AI总结 针对黑盒REST API测试缺乏代码覆盖率的问题,提出日志覆盖率指标,并评估进化计算、LLM和人工编写三种测试生成策略在Light-OAuth2系统上的效果。

Comments Accepted for publication in Proceedings of the 30th International Conference on Evaluation and Assessment in Software Engineering (EASE 2026)

详情
AI中文摘要

在黑盒设置中评估REST API测试的有效性可能具有挑战性,因为缺乏对源代码覆盖率指标和多语言技术栈的访问。我们提出了三个指标来捕获平均、最小和最大日志覆盖率,以处理多次运行中多样化的测试生成结果和运行时行为。使用日志覆盖率,我们在Light-OAuth2授权微服务系统上实证评估了三种REST API测试生成策略:进化计算(EvoMaster v5.0.2)、LLM(Claude Opus 4.6和GPT-5.2-Codex)以及人工编写的Locust负载测试。平均而言,Claude Opus 4.6测试比人工编写的测试发现多28.4%的唯一日志模板,而EvoMaster和GPT-5.2-Codex分别发现少26.1%和38.6%。接下来,我们分析组合日志覆盖率以评估策略之间的互补性。将人工编写的测试与Claude Opus 4.6测试相结合,人工编写测试和Claude测试的总观测日志覆盖率分别增加78.4%和38.9%。当将Locust测试与EvoMaster结合时,相同增加分别为30.7%和76.9%,而与GPT-5.2-Codex结合时为26.1%和105.6%。这意味着这些生成策略执行了很大程度上不同的运行时行为。我们的未来工作包括将研究扩展到多个系统。

英文摘要

Assessing the effectiveness of REST API tests in black-box settings can be challenging due to the lack of access to source code coverage metrics and polyglot tech stack. We propose three metrics for capturing average, minimum, and maximum log coverage to handle the diverse test generation results and runtime behaviors over multiple runs. Using log coverage, we empirically evaluate three REST API test generation strategies, Evolutionary computing (EvoMaster v5.0.2), LLMs (Claude Opus 4.6 and GPT-5.2-Codex), and human-written Locust load tests, on Light-OAuth2 authorization microservice system. On average, Claude Opus 4.6 tests uncover 28.4% more unique log templates than human-written tests, whereas EvoMaster and GPT-5.2-Codex find 26.1% and 38.6% fewer, respectively. Next, we analyze combined log coverage to assess complementarity between strategies. Combining human-written tests with Claude Opus 4.6 tests increases total observed log coverage by 78.4% and 38.9% in human-written and Claude tests respectively. When combining Locust tests with EvoMaster the same increases are 30.7% and 76.9% and when using GPT-5.2-Codex 26.1% and 105.6%. This means that the generation strategies exercise largely distinct runtime behaviors. Our future work includes extending our study to multiple systems.

2604.15008 2026-05-27 math.OA math.DG math.SP

Noncommutative Geometry, Spectral Asymptotics, and Semiclassical Analysis

非交换几何、谱渐近与半经典分析

Raphael Ponge

AI总结 本文结合泛函分析与谱理论技术,为一大类非交换流形(谱三元组)建立了半经典Weyl律并推广了Connes积分公式,去除了先前工作中的正则性与维数限制,并引入更弱的谱条件(Condition (W))以扩大适用范围。

Comments v3: the original paper is being split into 3 papers. This version keeps the main results and the applications to quantum tori. 58 pages

详情
AI中文摘要

半经典分析和非交换几何是量子理论的两大支柱。直到最近,它们之间的桥梁才逐渐显现。在本专著中,我们结合泛函分析和谱理论的各种技术,为一大类非交换流形(即谱三元组)获得了半经典Weyl律和Connes积分公式的推广。这些结果推广并简化了McDonald-Sukochev-Zanin的最新结果。特别是,我们的方法去除了那里的所有正则性假设和维数限制。此外,McDonald-Sukochev-Zanin使用的Tauber条件被一个更弱的谱理论条件(称为条件(W))所取代。该条件在相当广泛的 generality 下成立,并显著打开了主要结果的应用范围。我们还给出了蕴含条件(W)的Tauber条件。这些Tauber条件在实际中比McDonald-Sukochev-Zanin的Tauber条件更容易验证,并在众多例子中满足。这些条件的必要性由Alain Connes在一次在线研讨会上强调。本文的主要结果通过闭黎曼流形和量子环面上的半经典Weyl律和积分公式加以说明。在前者中,我们恢复了众所周知的半经典Weyl律以及Steklov特征值的Weyl律。唯一的新颖之处在于从Minakshisundaram-Pleijel关于热核渐近的旧结果中推导出它们。在量子环面的情形下,半经典Weyl律为Edward McDonald和作者的一个猜想提供了肯定答案。积分公式是对先前几个量子环面上Connes积分公式类结果的改进。

英文摘要

Semiclassical analysis and noncommutative geometry are two pillars of quantum theory. It is only recently that bridges between them have been emerging. In this monograph, we combine various techniques from functional analysis and spectral theory to obtain semiclassical Weyl laws and extensions of Connes' integration formula for a large class of noncommutative manifolds (i.e., spectral triples). These results generalize and simplify recent results of McDonald-Sukochev-Zanin. In particular, all the regularity assumptions and restrictions on dimension there are removed in our approach. Moreover, the Tauberian condition used by McDonald-Sukochev-Zanin is replaced by a weaker spectral theoretic condition, called Condition (W). That condition holds in fairly greater generality and significantly opens the scope of applicability of the main results. We also give Tauberian conditions that imply Condition (W). These Tauberian conditions are easier to check in practice than the Tauberian condition of McDonald-Sukochev-Zanin and are satisfied in numerous examples. The need for these conditions was highlighted by Alain Connes in an online seminar. The main results of this paper are illustrated by semiclassical Weyl laws and integration formulas in the settings of closed Riemannian manifolds and quantum tori. In the former settings we recover well-known semiclassical Weyl laws, as well as Weyl laws for Steklov eigenvalues. The only novelty is obtaining them from old results of Minakshisundaram-Pleijel on heat kernel asymptotics. In the setting of quantum tori, the semiclassical Weyl laws provide a positive answer to a conjecture of Edward McDonald and the author. The integration formulas are refinements of several previous analogues of Connes' integration formula for quantum tori.

2604.14269 2026-05-27 quant-ph cond-mat.quant-gas

AI-Enabled Decoding of Qubit Loss for Quantum Error-Correcting Codes

基于AI的量子纠错码量子比特丢失解码

Yuqing Wang, Xiaotian Nie, Jiale Dai, Zhongyi Ni, Tao Zhang, Hui Zhai, Linghui Chen

AI总结 针对量子比特丢失破坏稳定子代数结构的问题,提出基于时空图神经网络(STGNN)的解码器,同时纠正标准泡利错误和定位丢失位置,逻辑精度优于传统算法,并能在十轮后识别90%以上丢失位置。

详情
AI中文摘要

量子比特丢失是量子计算中的一个主要错误源,因为它破坏了量子纠错码标准稳定子形式的代数结构。一方面,它使解码复杂化;另一方面,它在稳定子中引入随机闪烁模式,作为量子比特丢失的标志。在这里,我们开发了一种基于人工智能的解码器,采用时空图神经网络(STGNN)架构,从综合征历史中提取时空相关性。我们的解码器执行双头任务,同时纠正标准泡利错误和识别量子比特丢失的位置。我们的解码器在逻辑精度上显著高于传统的最小权重完美匹配(MWPM)算法,甚至高于使用最后一轮量子比特丢失信息作为输入的延迟擦除MWPM解码器。我们的解码器还能在后续十轮稳定子测量累积后识别超过90%的丢失位置,从而促进量子比特重新初始化,例如通过原子阵列平台上的连续加载技术。对于这两项任务,我们的STGNN与修改版AlphaQubit的表现几乎相同,但它采用并行输入结构,在推理时间上优于修改版AlphaQubit的循环输入结构。这项工作为纠正量子比特丢失错误提供了一个稳健且可扩展的框架,为更高效的容错量子计算铺平了道路。

英文摘要

Qubit loss is a major source of error in quantum computation, as it invalidates the algebraic structure of the standard stabilizer formalism for quantum error-correcting codes. On the one hand, it complicates decoding; on the other hand, it introduces stochastic flicker patterns in stabilizers as a hallmark of qubit loss. Here, we develop an artificial-intelligence-enabled decoder based on a spatiotemporal Graph Neural Network (STGNN) architecture to extract spatial and temporal correlations from syndrome histories. Our decoder performs a dual-head task, simultaneously correcting standard Pauli errors and identifying the locations of qubit loss. Our decoder achieves significantly higher logical accuracy than both the traditional minimum-weight perfect matching (MWPM) algorithm and even delayed-erasure MWPM decoders that use qubit loss information from the final round as input. Our decoder can also identify more than 90% of loss locations after accumulating stabilizer measurements over the subsequent ten rounds, thereby facilitating qubit reinitialization, for instance, via the continuous loading technique on the atom array platform. For both tasks, our STGNN performs nearly identically to a modified version of AlphaQubit, but it employs a parallel input structure, giving it an advantage in inference time over modified AlphaQubit's recurrent input structure. This work provides a robust and scalable framework for correcting qubit loss errors, paving the way for more efficient fault-tolerant quantum computation.

2502.06229 2026-05-27 math.OA math-ph math.MP math.QA

Constructing equivalences between quantum group fusion categories and Huang-Lepowsky modular categories via quantum gauge groups

通过量子规范群构造量子群融合范畴与Huang-Lepowsky模范畴之间的等价

Claudia Pinzari

AI总结 本文通过构造全局量子规范群和广义量子Schur-Weyl对偶,统一解决了Doplicher-Roberts问题和Huang问题,建立了量子群融合范畴与Huang-Lepowsky模范畴之间的等价。

Comments 54 pages. Restructured version. We have redistributed material from the related joint manuscript arXiv:2101.10016 that in turn will be cut down from that paper

详情
AI中文摘要

本文提供了一个统一框架,解决了两个长期存在的问题:辫子张量$C^*$-范畴的全局量子规范群的内在构造(Doplicher-Roberts问题)以及正整数水平下Finkelberg等价定理的直接证明(Huang问题)。在我们之前的工作中,我们通过在所有李型WZW模型的仿射顶点算子代数的模范畴上构造酉模张量范畴结构,以及我们的解析结构的量子规范群,解决了这两个问题。具体地,我们利用全局量子规范群$A_{W}(\mathfrak{g},q)$为仿射顶点算子代数$V_{\mathfrak{g}_{k}}$的Zhu代数装备了一个具有3-上边界结合子的酉上边界弱拟Hopf代数结构。这依赖于一个等距解析Drinfeld扭曲和Wenzl的连续去量子化曲线。在本文中,我们专门针对Huang-Lepowsky张量结构处理Huang问题。通过广义量子Schur-Weyl对偶,我们为所有经典李型和$G_2$提供了我们的模张量范畴结构与Huang-Lepowsky结构的完全等同。这种统一方法直接从量子群融合范畴建立了刚性,完全绕过了对Verlinde公式、Knizhnik-Zamolodchikov方程的单值性、VOA设置中通常需要的负能级平移以及共形网设置中使用的Jones指标的依赖。因此,我们的框架恢复了自然的范畴层次结构,其中局部刚性先于全局模性质,完全在顶点算子代数设置内。

英文摘要

This paper provides a unified framework resolving two long-standing problems: the intrinsic construction of global quantum gauge groups for braided tensor $C^*$-categories (the Doplicher-Roberts problem) and the direct proof of the Finkelberg equivalence theorem at positive integer levels (the Huang problem). In our previous work, we solved both problems for the WZW model across all Lie types by constructing a unitary modular tensor category structure on the module category of an affine vertex operator algebra at positive integer level, together with a quantum gauge group for our analytic structure. Specifically, we utilized the global quantum gauge group A_{W}(\mathfrak{g},q) to equip the Zhu algebra of the affine vertex operator algebra V_{\mathfrak{g}_{k}} with a unitary coboundary weak quasi-Hopf algebra structure with a 3-coboundary associator. This relies on an isometric analytic Drinfeld twist and Wenzl's continuous de-quantization curve. In the present paper, we address the Huang problem specifically for the Huang-Lepowsky tensor structure. We provide a complete identification of our modular tensor category structure with the Huang-Lepowsky structure for all the classical Lie types and $G_2$ via generalized quantum Schur-Weyl duality. This unified approach establishes rigidity directly from the quantum group fusion category, completely bypassing reliance on the Verlinde formula, the monodromy of the Knizhnik-Zamolodchikov equations, negative-level shifting typically required in the VOA setting, and the Jones index used in the conformal net setting. Consequently, our framework restores the natural categorical hierarchy where local rigidity precedes global modular properties entirely within the vertex operator algebra setting.

2604.11481 2026-05-27 astro-ph.CO math-ph math.MP nlin.PS physics.data-an stat.AP

Emergence of Complex Web Structures

复杂网络结构的涌现

Francisco-Shu Kitaura

AI总结 本文通过结合半微观相空间动力学、输运几何、信息论和粗粒化有效建模的统一框架,解释了从均匀或弱相关状态涌现出复杂结构时熵增与有序化之间的表观矛盾。

Comments 38 pages, 8 figures, revised manuscript after referee report

详情
AI中文摘要

复杂结构通常从初始均匀或弱相关状态涌现。我们通过一个结合半微观相空间动力学、输运几何、信息论和粗粒化有效建模的统一框架,解决了这种有序化与熵增之间的表观矛盾。关键在于熵依赖于描述层次:当结构形成时,粗粒化的空间场可能变得更加有序,而完整的相空间描述则通过壳交叉、多流以及速度自由度的激活变得更加复杂。利用拉格朗日-欧拉输运映射,我们展示了密度放大如何由变形的雅可比行列式控制,以及各向异性坍缩如何从变形张量层次的特征值产生。长程相互作用或信息流编码在位移场中,因此非局域性直接通过输运进入。我们将这种几何描述与最大熵高斯基线联系起来,并展示了非线性输运和非局域耦合如何产生尺度耦合、高阶相关和非高斯性。然后,我们构建了一个朗道-金兹堡描述,其中种子各向异性的增长被解释为较低有效自由能分支的激活,提供了自组织的粗粒化实现。应用于生成的宇宙学场,该框架表明非局域潮汐水平在中等过密度时已经变得相关。尽管宇宙学结构形成是这里考虑的主要实现,但该框架旨在更广泛地作为输运、各向异性、非局域性和自组织为核心的系统的一种介观语言。

英文摘要

Complex structures often emerge from initially homogeneous or weakly correlated states. We address the apparent tension between this ordering and entropy growth through a unified framework combining semi-microscopic phase-space dynamics, transport geometry, information theory, and coarse-grained effective modeling. The key point is that entropy depends on the level of description: a coarse-grained spatial field may become more ordered as structure forms, even while the full phase-space description becomes more complex through shell crossing, multistreaming, and the activation of velocity degrees of freedom. Using a Lagrangian--Eulerian transport map, we show how density amplification is governed by the Jacobian of the deformation and how anisotropic collapse arises from the eigenvalues of a hierarchy of deformation tensors. Long-range interaction or information flow is encoded in the displacement field, so that nonlocality enters directly through transport. We connect this geometric description to a maximum-entropy Gaussian baseline and show how nonlinear transport and nonlocal coupling generate scale coupling, higher-order correlations, and non-Gaussianity. We then formulate a Landau--Ginzburg description in which the growth of seed anisotropies is interpreted as the activation of lower effective free-energy branches, providing a coarse-grained realization of self-organization. Applied to generated cosmological fields, this framework indicates that the nonlocal tidal level becomes relevant already at moderate overdensity. Although cosmological structure formation is the main realization considered here, the framework is intended more broadly as a mesoscopic language for systems in which transport, anisotropy, nonlocality, and self-organization are central.

2604.11189 2026-05-27 astro-ph.SR

Fundamental properties of two rapidly rotating stars: Rasalhague and Alkaid

两颗快速自转恒星的基本性质:Rasalhague 和 Alkaid

Axel Lazzarotto, Alain Hui-Bon-Hoa, Torsten Boehm, Matthew Gent, Michel Rieutord

AI总结 利用五类分光光度观测量和二维稳态模型网格,反演快速自转恒星 Rasalhague 和 Alkaid 的质量、自转速率、年龄及自转轴倾角等基本参数。

Comments 9 pages, 8 figures, accepted for publication in Astronomy & Astrophysics

Journal ref A&A 709, A251 (2026)

详情
AI中文摘要

摘要:快速自转恒星的基本参数是理解自转对恒星演化影响的关键量。几颗邻近的早型星为精确测量这些参数提供了可能,这将有助于我们约束新近可用的二维模型。我们提出了一种方法,利用五类分光光度观测量和一组稳态二维模型,来获取快速自转恒星的基本参数(质量、自转速率和年龄),以及其自转轴相对于视线的倾角。利用红外流量法得到的温度、Vsini 和视光度,结合二维稳态模型网格,我们选出与所有观测约束兼容的模型,并推导出目标恒星最可能的质量、自转速率、核心氢质量分数相对于包层的比值,以及自转轴相对于视线的倾角。我们将此方法应用于两颗恒星:Rasalhague(蛇夫座α)和 Alkaid(大熊座η)。我们确认并改进了 Rasalhague 的基本参数,并首次确定了其自转轴倾角约为69度。对于 Alkaid,我们推断其质量为 $5.071\pm0.023 M_\odot$,自转速率对应的赤道自转周期为14.6小时。我们还发现其自转轴倾角约为42度。我们表明 Alkaid 是一颗非常年轻的恒星,可能位于零龄主序带之后2到8百万年。作为附带结果,利用高分辨率光谱和最小二乘反卷积方法,我们精确测定了 Rasalhague 的 Vsini 值为 $224.3\pm2.6$ km/s。类似地,我们得到 Alkaid 的 $V\sin i=154.3\pm9.1$ km/s。

英文摘要

Abridged : The fundamental parameters of rapidly rotating stars are key quantities to understand the impact of rotation on stellar evolution. A few nearby early-type stars offer the possibility of precise measurements of these parameters, which will help us constrain newly available two-dimensional models. We propose a method to retrieve the fundamental parameters of a fast rotating star (mass, rotation rate, and age), and also the inclination of its rotation axis on the line of sight, using five spectrophotometric observables along with a set of steady 2D-models. Using the temperature derived by the infrared flux method, the Vsini and the apparent luminosity, along with a grid of 2D steady state models, we select models that are compatible with all observational constraints, and derive the most probable mass, rotation rate, core hydrogen mass fraction relative to that of the envelope, and inclination of the rotation axis on the line of sight of the targetted star. We apply this method to two stars: Rasalhague (alpha Oph) and Alkaid (eta UMa). We confirm and improve the fundamental parameters of Rasalhague and provide a new determination of its rotation axis inclination on the line-of-sight, which we find to be $\sim69$ degrees. Concerning Alkaid, we infer a mass of $5.071\pm0.023 M_\odot$, a rotation rate corresponding to an equatorial rotation period of 14.6 hours. We also find an inclination of the rotation axis of $\sim42$ degrees. We show that Alkaid is a very young star, presumably between 2 and 8 Myrs off the Zero-Age Main Sequence. As a side result, using high resolution spectra and the Least Square Deconvolution method, we determined a precise value of the Vsini of Rasalhague, namely $224.3\pm2.6$ km/s. Similarly, we find $V\sin i=154.3\pm9.1$ km/s for Alkaid.

2604.00450 2026-05-27 math.RA

Point modules over the universal enveloping algebras of color Lie algebras

颜色李代数泛包络代数上的点模

Shu Minaki

AI总结 本文定义了Z-分次k-代数中的q'-海森堡正规元,并利用它刻画了颜色李代数泛包络代数(Artin-Schelter正则代数)上的点模集,同时给出了截断点概形逆系统为常数的具体整数,定量回答了Artin-Tate-Van den Bergh的问题。

Comments 16 pages

详情
AI中文摘要

设$k$是特征为零的代数闭域。本文定义了$\mathbb{Z}$-分次$k$-代数中$q'$-海森堡正规元的概念。该$q'$-海森堡正规元给出了与点模相关的一些模集的结构。我们还确定了作为颜色李代数泛包络代数的Artin--Schelter正则代数上的点模集。此外,我们给出了一个具体的整数,使得其截断点概形的逆系统是常数。这是对我们设定下Artin--Tate--Van den Bergh提出的问题的一个定量回答。

英文摘要

Let $k$ be an algebraically closed field with characteristic zero. In this paper, we define the notion of a $q'$-Heisenberg normal element of a $\mathbb{Z}$-graded $k$-algebra. This $q'$-Heisenberg normal element gives the structure of some sets of modules related to point modules. We also determine the set of point modules over an Artin--Schelter regular algebra obtained as the universal enveloping algebra of a color Lie algebra. Moreover, we give a concrete integer such that the inverse system of its truncated point schemes is constant. This is a quantitative answer to a question raised by Artin--Tate--Van den Bergh, in our setting.

2604.08397 2026-05-27 math.CO

4-cycle-free induced subgraphs of grid graphs

网格图的4-循环无诱导子图

Taiki Aiba, Ernie Croot

AI总结 研究二维网格图中避免诱导4-循环的最大顶点集,并给出略小于最大值的诱导C4-无子图数量的上下界。

Comments A few small corrections were made to previous draft. Taiki was an undergrad student; this is sort of like an REU paper

详情
AI中文摘要

在Alon等人以及后来的Caragiannis等人的研究中,已经研究了$d$维网格图(或格图)中避免诱导森林(即诱导无圈子图)的问题,找到了关于单维顶点数$n$和维度$d$的上下界。本文研究了二维网格图$G$中避免诱导$C_4$-无子图(诱导森林的超集)的问题,刻画了使得$G$的诱导子图$G_S$(顶点集为$S$)是$C_4$-无的最大集合$S \subseteq V$。此外,我们给出了顶点数略小于最大值的$C_4$-无诱导子图数量的上下界。

英文摘要

The avoidance of induced forests, or induced acyclic subgraphs, in $d$-dimensional grid graphs, or lattice graphs, has been studied in Alon et al. and later in Caragiannis et al., finding upper and lower bounds with respect to the number of vertices in a single dimension $n$ and the dimension $d$. In this work, we study the avoidance of induced $C_4$-free subgraphs, a superset of induced forests, of $2$-dimensional grid graphs $G$ and characterize the maximal sets $S \subseteq V$ such that the induced subgraph $G_S$ of $G$ with vertex set $S$ is $C_4$-free. Additionally, we will give upper and lower bounds on the number of $C_4$-free induced subgraphs with slightly fewer vertices than contained in the maximum.

2604.08318 2026-05-27 quant-ph

A Model Context Protocol Server for Quantum Execution in Hybrid Quantum-HPC Environments

用于混合量子-HPC环境中量子执行的模型上下文协议服务器

Masaki Shiraishi, Ikko Hamamura, Tatsuya Ishigaki, Tadashi Kadowaki

AI总结 提出基于MCP服务器的AI驱动框架,使LLM代理能通过自然语言自动执行量子计算工作流,包括采样和期望值计算等原语。

Comments Accepted to QC4C3 workshop at QCNC 2026

详情
AI中文摘要

大型语言模型(LLM)融入科学研究正在加速实现自主“AI科学家”。尽管近期进展使AI能够提出假设和设计实验,但在执行这些任务方面仍存在关键差距,特别是在量子计算(QC)领域。执行量子算法不仅需要生成代码,还需要管理诸如QPU和高性能计算(HPC)集群等复杂计算资源。本文提出一个AI驱动框架,通过实现模型上下文协议(MCP)服务器专门弥合这一执行差距。我们的系统使LLM代理能够处理作为作业一部分提交的自然语言提示,通过MCP调用我们的工具自主执行量子计算工作流。我们通过执行基本量子算法原语(包括采样和期望值计算)来展示该框架的能力。关键技术贡献包括:用于量子执行的MCP服务器开发、解释OpenQASM代码的流水线、用于ABCI-Q混合平台的CUDA-Q自动化工作流,以及通过CUDA-Q使用Quantinuum模拟器进行远程量子硬件的异步执行流水线。本工作验证了AI代理可以通过基于MCP的架构有效抽象硬件交互的复杂性,从而促进实用量子研究的自动化。

英文摘要

The integration of large language models (LLMs) into scientific research is accelerating the realization of autonomous ``AI Scientists.'' While recent advancements have empowered AI to formulate hypotheses and design experiments, a critical gap remains in the execution of these tasks, particularly in the domain of quantum computing (QC). Executing quantum algorithms requires not only generating code but also managing complex computational resources such as QPUs and high-performance computing (HPC) clusters. In this paper, we propose an AI-driven framework specifically designed to bridge this execution gap through the implementation of a Model Context Protocol (MCP) server. Our system enables an LLM agent to process natural language prompts submitted as part of a job, autonomously executing quantum computing workflows by invoking our tools via the MCP. We demonstrate the framework's capability by performing essential quantum algorithmic primitives, including sampling and computation of expectation values. Key technical contributions include the development of an MCP server for quantum execution, a pipeline for interpreting OpenQASM code, an automated workflow with CUDA-Q for the ABCI-Q hybrid platform, and an asynchronous execution pipeline for remote quantum hardware using the Quantinuum emulator via CUDA-Q. This work validates that AI agents can effectively abstract the complexities of hardware interaction through an MCP-based architecture, thereby facilitating the automation of practical quantum research.

2604.07614 2026-05-27 eess.IV

MetaTele: Compact Refractive Metasurface Computational Telephoto Camera

MetaTele: 紧凑型折射超表面计算长焦相机

Harshana Weligampola, Yuanrui Chen, Abhiram Gnanasambandam, Dilshan Godaliyadda, Hamid R. Sheikh, Stanley H. Chan, Qi Guo

AI总结 提出一种光学-算法协同设计MetaTele,通过窄带结构成像与宽带颜色线索的分离采集,结合单步扩散模型融合,实现0.44超低长焦比(TTL仅13mm)的RGB成像。

详情
AI中文摘要

智能手机相机面临基本的外形因素限制,限制了其光学放大能力,主要原因是难以降低镜头组的长焦比,即总轨迹长度(TTL)与有效焦距(EFL)之比。目前,传统折射光学难以在不使用多个笨重元件校正像差的情况下实现低于0.5的长焦比。在本文中,我们介绍了MetaTele,一种新颖的光学-算法协同设计,突破了这一瓶颈。MetaTele明确地将场景结构和颜色信息的采集解耦。首先,它利用紧凑的折射-超表面光学组件在窄波长带下捕获精细细节的结构图像,从本质上避免了严重的色差。其次,它使用相同的光学器件捕获宽带颜色线索;尽管该线索受到色差的严重破坏,但它保留了足够的光谱信息来指导后处理。然后,我们采用定制的单步扩散模型计算性地融合这两个原始测量结果,成功地对结构图像进行着色,同时校正系统像差。我们展示了一个MetaTele原型,实现了前所未有的0.44长焦比,RGB成像的TTL仅为13毫米,为在智能手机外形中实现单反级长焦能力铺平了道路。

英文摘要

Smartphone cameras face fundamental form-factor constraints that limit their optical magnification, primarily due to the difficulty of reducing a lens assembly's telephoto ratio, the ratio between total track length (TTL) and effective focal length (EFL). Currently, conventional refractive optics struggle to achieve a telephoto ratio below 0.5 without requiring multiple bulky elements to correct optical aberrations. In this paper, we introduce MetaTele, a novel optics-algorithm co-design that breaks this bottleneck. MetaTele explicitly decouples the acquisition of scene structure and color information. First, it utilizes a compact refractive-metasurface optical assembly to capture a fine-detail structure image under a narrow wavelength band, inherently avoiding severe chromatic aberrations. Second, it captures a broadband color cue using the same optics; although this cue is heavily corrupted by chromatic aberrations, it retains sufficient spectral information to guide post-processing. We then employ a custom one-step diffusion model to computationally fuse these two raw measurements, successfully colorizing the structure image while correcting for system aberrations. We demonstrate a MetaTele prototype, achieving an unprecedented telephoto ratio of 0.44 with a TTL of just 13 mm for RGB imaging, paving the way for DSLR-level telephoto capabilities within smartphone form factors.

2604.06986 2026-05-27 astro-ph.GA

Large Interstellar Polarisation Survey. III. Observational constraints on the structure of grains

大型星际偏振巡天. III. 尘埃结构的观测约束

Ralf Siebenmorgen, Stefano Bagnulo, Lapo Fanciullo, Thomas Vannieuwenhuyse, Vincent Guillet

AI总结 利用96条视线上的红化曲线、星光偏振光谱和偏振尘埃发射数据,结合三组分尘埃模型,约束了弥漫星际介质中尘埃颗粒的结构、组成、尺寸分布和排列特性。

Comments accepted by A&A

Journal ref A&A 709, A277 (2026)

详情
AI中文摘要

弥漫星际介质中的尘埃在颗粒结构、组成、尺寸分布和排列特性方面仍不完全清楚。对单个视线的红化、星光偏振光谱和偏振尘埃发射的联合观测为这些特性提供了重要约束。我们研究了96条远紫外选样本的红化曲线,这些曲线的光学线性偏振光谱是作为大型星际偏振巡天(LIPS)的一部分,使用VLT上的FORS获得的。本文展示了60颗恒星的星光偏振光谱。这些数据与Gaia距离估计和Planck热尘埃发射相结合。公开了一个三组分尘埃模型,包括纳米颗粒、非晶颗粒和微米级尘埃聚集体,通过改变轴比、孔隙率、尺寸、元素丰度和排列效率来匹配观测结果。红化和偏振光谱的多样性可以通过典型的轴比为2、孔隙率为10%和高排列效率的长椭球颗粒很好地再现。这种效率可以通过辐射扭矩排列理论(RAT)实现,但通过不完美的Davis-Greenstein(IDG)排列则不能,除非调整磁场方向以最大化偏振。微米级尘埃在光学中贡献波长无关的灰色消光,约占视觉消光的三分之一,并携带三分之一的尘埃质量。后续的高分辨率偏振亚毫米巡天将进一步约束颗粒形状和排列物理。

英文摘要

Dust in the diffuse interstellar medium remains incompletely understood with regard to the structure, composition, size distribution, and alignment properties of the grains. Joint observations of reddening, starlight polarisation spectra, and polarised dust emission for individual sightlines provide essential constraints on such properties. We study a far-UV selected sample of 96 reddening curves, for which optical linear polarisation spectra were obtained with FORS at the VLT as part of the Large Interstellar Polarisation Survey (LIPS). Starlight polarisation spectra for 60 stars are presented in this work. These data are combined with Gaia distance estimates and Planck thermal dust emission. A three-component dust model is made publicly available. It consists of nanoparticles, amorphous grains, and micrometre-sized dust agglomerates, varying axial ratios, porosities, sizes, element abundances, and alignment efficiencies to match the observations. The diversity of reddening and polarisation spectra is well reproduced by prolate grains with typical axial ratios of two, a porosity of 10%, and high alignment efficiencies. Such efficiencies can be achieved with radiative torque alignment theory (RAT), but not with imperfect Davis-Greenstein (IDG) alignment, except when adjusting the magnetic-field orientation to maximise the polarisation. Micrometre-sized dust contributes wavelength-independent grey extinction in the optical, accounts for about one-third of the visual extinction, and carries one-third of the dust mass. A follow-up submillimetre survey with high-resolution polarimetry will further constrain grain shapes and alignment physics.

2604.06821 2026-05-27 astro-ph.SR

Magnetic geometry of M dwarfs in the southern PLATO field

南天PLATO视场中M矮星的磁几何

M. Diez, P. I. Cristofari, J. Morin, P. Petit, S. Bellotti, A. Vidotto, A. Carmona, X. M. Delfosse, C. P. Folsom, G. A. J. Hussain, A. F. Lanza, S. Messina

AI总结 通过分析6颗M矮星的TESS光变曲线和SPIRou光谱偏振数据,利用ZDI技术重建大尺度磁场拓扑,揭示了快速自转早型M矮星可产生偶极主导磁场、快速自转中M矮星可产生非轴对称大尺度磁场、中等自转早型M矮星磁场异常微弱等多样性特征。

Comments Accepted in Astronomy & Astrophysics. 13 pages, 10 figures, 3 tables, 9 appendices. v2: corrected ncyc values in Table E1 (Appendix E)

Journal ref A&A 709, A273 (2026)

详情
AI中文摘要

M矮星是银河系中最丰富的恒星,表现出多样的磁性行为。理解它们的大尺度磁场对于研究恒星发电机和评估磁活动对行星环境的影响至关重要,然而它们的磁性质和长期变率仍缺乏充分描述。我们旨在表征南天PLATO视场中6颗M矮星的大尺度磁场,其自转周期约为1至17天,质量在0.26至0.64太阳质量之间。五颗星为部分对流,一颗为完全对流,将质量-自转图扩展到先前未采样的区域。我们分析了TESS光变曲线以确定准确的自转周期并优化光谱偏振观测的相位覆盖。对SPIRou数据进行处理以获得LSD轮廓和纵向磁场测量,同时通过合成光谱拟合获得小尺度场强。应用ZDI重建大尺度磁场拓扑。我们报告了6颗M矮星中磁场拓扑的广泛多样性,主要有3个结果:(1)快速自转(Prot < 2天)的早型M矮星可以产生中等强度的偶极主导磁场,类似于质量更小的中M矮星;(2)快速自转的中M矮星可以产生具有显著环向分量的非轴对称大尺度磁场;(3)一颗中等自转(Prot ~ 17天)的早型M矮星显示出异常微弱的大尺度磁场。我们的发现强调了磁场构型的多样性,包括在先前未探索的区域。长期监测对于区分持续特征与变率驱动的偏移以及表征表面磁场的演化至关重要。互补的PLATO测光,包括耀斑和黑子诱导变率分析,对于将表面活动与磁性质联系起来至关重要。

英文摘要

M dwarfs are the most abundant stars in the Galaxy and exhibit diverse magnetic behaviours. Understanding their large-scale magnetic fields is essential to study stellar dynamos and assess the impact of magnetic activity on planetary environments, yet their magnetic properties and long-term variability remain poorly characterised. We aim to characterise the large-scale magnetic fields of 6 M dwarfs in the southern PLATO field, with rotation periods from ~1 to 17 days and masses between 0.26 and 0.64 Msun. Five stars are partially convective, one fully convective, extending the mass-rotation diagram to previously unsampled regions. We analysed TESS light curves to determine accurate rotation periods and optimise phase coverage for spectropolarimetric observations. SPIRou data were reduced to obtain LSD profiles and longitudinal field measurements, while synthetic spectra fitting yielded small-scale field strengths. ZDI was applied to reconstruct large-scale magnetic topologies. We report a wide diversity of magnetic topologies among the 6 M dwarfs, with 3 main results: (1) Rapidly-rotating (Prot < 2 d) early M dwarfs can generate dipole-dominated fields of moderate intensity, similar to less massive mid-M dwarfs; (2) rapidly-rotating mid-M dwarfs can generate non-axisymmetric large-scale fields with a significant toroidal component; (3) a moderately-rotating (Prot ~ 17 d) early M dwarf shows a surprisingly weak large-scale field. Our findings highlight the diversity of magnetic configurations, including in previously unexplored regions. Long-term monitoring is crucial to distinguish persistent features from variability-driven excursions and to characterise the evolution of surface magnetic fields. Complementary PLATO photometry, including flare and spot-induced variability analyses, will be essential to link surface activity with magnetic properties.

2604.06645 2026-05-27 math.PR math.AP

Global in time solutions to stochastic reaction-diffusion systems with superlinear reactions satisfying a triangular control of mass

具有满足三角质量控制的超线性反应的随机反应扩散系统的全局时间解

Dionysis Milesis, Michael Salins

AI总结 研究受乘性噪声扰动的反应扩散系统,在反应项满足拟正性、三角质量控制和多项式增长条件下,证明全局解的存在性。

Comments 38 pages

详情
AI中文摘要

我们研究受乘性噪声扰动的反应扩散方程系统,其中反应项满足拟正性、三角质量控制和多项式增长。我们的结果适用于化学和生物学中最常见的一类反应扩散系统。在确定性设定中,已知这些假设能保证解的全局存在性。然而,在随机设定中,反应扩散系统通常是在不同的反应假设下进行分析的,这些假设排除了许多自然模型,例如由质量作用定律建模的可逆化学反应网络,而质量控制结构下的全局存在性和唯一性问题一直悬而未决。在这项工作中,我们表明,通过适当的乘性噪声随机扰动具有三角质量控制的反应扩散系统,可以得到对所有时间存在的解。

英文摘要

We study systems of reaction-diffusion equations perturbed by multiplicative noise, where the reaction terms satisfy quasipositivity, a triangular mass-control structure, and polynomial growth. Our results apply to a broad class of reaction-diffusion systems arising, most notably, in chemistry and biology. In the deterministic setting these assumptions are known to guarantee the global existence of solutions. In the stochastic setting, however, reaction-diffusion systems have typically been analyzed under different assumptions on the reactions that preclude many natural models, such as reversible chemical reaction networks modeled by the mass-action law, and the question of global existence and uniqueness under a mass-control structure has remained open. In this work, we show that stochastically perturbing reaction-diffusion systems with triangular control of mass by suitable multiplicative noise leads to solutions that exist for all time.

2604.06301 2026-05-27 hep-th

$c=1$ strings as a matrix integral

$c=1$ 弦作为矩阵积分

Scott Collier, Lorenz Eberhardt, Victor A. Rodriguez

AI总结 通过谱曲线将 $c=1$ 弦的微扰 $S$-矩阵描述为双标度 (0+0) 维矩阵积分,建立世界 sheet 描述、矩阵量子力学和矩阵积分之间的三重性。

Comments 66 pages + appendices. v2: references updated, introduction expanded

详情
AI中文摘要

我们研究 $c=1$ 弦的微扰 $S$-矩阵,并证明它可以通过基于谱曲线 $\mathsf{x}(z) = 2\sqrt{2}\cos(z)$、$\mathsf{y}(z)=\sin(z)$ 的双标度 (0+0) 维矩阵积分来描述。结合与矩阵量子力学的著名对偶性,这建立了该理论的三种表述之间的三重性:世界 sheet 描述、矩阵量子力学和矩阵积分。从复刘维尔弦的交点数表达式出发,我们推导出 $c=1$ 振幅的闭式费曼规则表达式,作为黎曼曲面模空间上的交点数。交数理论自然地计算对应于离散靶空间的振幅,其中动量仅模整数守恒。通过限制到第一“布里渊区”并解析延拓到洛伦兹运动学,恢复物理 $S$-矩阵元。我们直接从交数理论表达式证明这些振幅满足微扰时空幺正性,并表明它们满足 Mirzakhani 型递归关系。我们展示了与已知矩阵量子力学结果的详细一致性,为三重性提供了有力证据。

英文摘要

We study the perturbative $S$-matrix of the $c=1$ string and show that it admits a description in terms of a double-scaled (0+0)-dimensional matrix integral based on the spectral curve $\mathsf{x}(z) = 2\sqrt{2}\cos(z)$, $\mathsf{y}(z)=\sin(z)$. Combined with the famous duality to matrix quantum mechanics, this establishes a triality between three formulations of the theory: the worldsheet description, matrix quantum mechanics, and a matrix integral. Starting from the intersection number expressions for the complex Liouville string, we derive closed-form Feynman rule expressions for the $c=1$ amplitudes as intersection numbers on the moduli space of Riemann surfaces. The intersection theory naturally computes amplitudes corresponding to a discretized target space where momentum is conserved only modulo an integer. The physical $S$-matrix elements are recovered by restriction to the first `Brillouin zone' and analytic continuation to Lorentzian kinematics. We prove that these amplitudes satisfy perturbative spacetime unitarity directly from the intersection theory expressions, and show that they satisfy a Mirzakhani-type recursion relation. We show detailed agreement with the known matrix quantum mechanics results, providing strong evidence for the triality.

2603.28096 2026-05-27 cs.NI

Beyond Traffic Matrix: DELTA -- A DAG-Aware OCS Logical Topology Optimization for AIDCs

超越流量矩阵:DELTA——一种面向AIDC的DAG感知OCS逻辑拓扑优化

Niangen Ye, Jingya Liu, Guofu Zhu, Weiqiang Sun, Weisheng Hu

AI总结 提出DELTA框架,利用计算通信有向无环图(DAG)将时变流量模式编码为混合整数线性规划(MILP)模型,通过可变长度时间间隔公式和双轨加速策略优化光学电路开关(OCS)逻辑拓扑,减少通信时间并节省光端口。

详情
AI中文摘要

大型语言模型(LLM)的快速扩展加剧了AI数据中心(AIDC)中的通信瓶颈。为了克服这一问题,光学电路开关(OCS)因其优越的带宽容量和能效而被广泛采用。然而,它们的重配置开销阻碍了迭代内拓扑更新,需要先验地设计静态拓扑以吸收时变的LLM流量。现有方法基于流量矩阵设计这些拓扑,但这种表示掩盖了由并行化策略决定的突发并发带宽需求,并且未能考虑并发通信所需的独立通道。为了解决这个问题,我们提出了DELTA,一种高效的AIDC逻辑拓扑优化框架,它利用计算通信有向无环图(DAG)将时变流量模式编码为混合整数线性规划(MILP)模型,同时利用非关键任务的时间松弛来节省光端口而不影响迭代完成时间。通过首创可变长度时间间隔公式,DELTA相比固定时间步长公式显著减少了求解空间。为了扩展到千GPU集群,我们设计了一种双轨加速策略,结合搜索空间剪枝(将复杂度从二次降低到线性)和启发式热启动。在大规模LLM工作负载上的评估表明,与最先进的基于流量矩阵的基线相比,DELTA将通信时间减少了高达17.5%。此外,该框架将光端口消耗减少了至少20%;动态重新分配这些多余端口给带宽瓶颈工作负载,使其与理想非阻塞电网络的性能差距缩小了高达26.1%,最终使大多数工作负载实现接近理想的性能。

英文摘要

The rapid scaling of large language models (LLMs) exacerbates communication bottlenecks in AI data centers (AIDCs). To overcome this, optical circuit switches (OCS) are increasingly adopted for their superior bandwidth capacity and energy efficiency. However, their reconfiguration overhead precludes intra-iteration topology update, necessitating a priori engineering of a static topology to absorb time-varying LLM traffic. Existing methods engineer these topologies based on traffic matrices. However, this representation obscures the bursty concurrent bandwidth demands dictated by parallelization strategies and fails to account for the independent channels required for concurrent communication. To address this, we propose DELTA, an efficient logical topology optimization framework for AIDCs that leverages the computation-communication directed acyclic graph (DAG) to encode time-varying traffic patterns into a Mixed-Integer Linear Programming (MILP) model, while exploiting the temporal slack of non-critical tasks to save optical ports without penalizing iteration makespan. By pioneering a variable-length time interval formulation, DELTA significantly reduces the solution space compared to the fixed-time-step formulation. To scale to thousand-GPU clusters, we design a dual-track acceleration strategy that combines search space pruning (reducing complexity from quadratic to linear) with heuristic hot-starting. Evaluations on large-scale LLM workloads show that DELTA reduces communication time by up to 17.5% compared to state-of-the-art traffic-matrix-based baselines. Furthermore, the framework reduces optical port consumption by at least 20%; dynamically reallocating these surplus ports to bandwidth-bottlenecked workloads reduces their performance gap relative to ideal non-blocking electrical networks by up to 26.1%, ultimately enabling most workloads to achieve near-ideal performance.

2601.04512 2026-05-27 cs.CR cs.CY

Application of Hybrid Chain Storage Framework in Energy Trading and Carbon Asset Management

混合链存储框架在能源交易与碳资产管理中的应用

Yinghan Hou, Zongyou Yang, Xiaokun Yang

AI总结 针对分布式能源交易与碳资产管理中高频小额结算的审计需求,提出一种链上链下混合结算框架,通过链上锚定结算承诺与关键约束、链下记录确定性摘要与可重放审计,在公开约束工作负载下显著降低链上执行与存储成本并保持审计可信性。

Comments 13 pages, 5 figures

详情
AI中文摘要

分布式能源交易和碳资产管理涉及高频、小额的结算,并具有强烈的审计需求。完全链上设计会产生过高的成本,而纯链下方法缺乏可验证的一致性。本文提出了一种链上链下混合结算框架,该框架将结算承诺和关键约束锚定在链上,并通过确定性摘要和可重放审计链接链下记录。在公开约束工作负载下的实验表明,该框架显著降低了链上执行和存储成本,同时保持了审计的可信性。

英文摘要

Distributed energy trading and carbon asset management involve high-frequency, small-value settlements with strong audit requirements. Fully on-chain designs incur excessive cost, while purely off-chain approaches lack verifiable consistency. This paper presents a hybrid on-chain and off-chain settlement framework that anchors settlement commitments and key constraints on-chain and links off-chain records through deterministic digests and replayable auditing. Experiments under publicly constrained workloads show that the framework significantly reduces on-chain execution and storage cost while preserving audit trustworthiness.

2603.24817 2026-05-27 astro-ph.GA

ALMAGAL VIII. Early phases of triggered star formation in source AG286.0716$-$1.8229

ALMAGAL VIII. 源AG286.0716$-$1.8229中触发恒星形成的早期阶段

C. Mininni, S. Molinari, W. J. Kim, E. Schisano, F. Fontani, A. Traficante, A. Nucara, A. Coletta, H. T. Lee, Á. Sanchez-Monge, M. Benedettini, D. Elia, S. Pezzuto, V. M. Pelkonen, P. Schilke, C. Battersby, P. T. P. Ho, M. Beltrán, H. Beuther, G. A. Fuller, B. Jones, R. S. Klessen, Q. Zhang, S. Walch, Y. Tang, A. Ahmadi, J. Allande, A. Avison, J. Ballesteros-Paredes, L. Bronfman, C. L. Brogan, F. De Angelis, E. Rodrigues da Costa, P. Hennebelle, T. R. Hunter, K. J. Johnston, K. T. Kim, P. Klaassen, R. Kuiper, C. Y. Law, D. C. Lis, S. Liu, L. Moscadelli, T. Möller, K. L. J. Rygl, P. Sanhueza, J. D. Soler, Y. N. Su, L. Testi, F. F. S. van der Tak, T. Zhang, H. Zinnecker, J. Wallace

AI总结 利用ALMAGAL巡天和ALMA后续观测,研究H II区膨胀触发的恒星形成,通过尘埃连续谱和分子谱线分析,在源AG286.0716$-$1.8229中探测到9个核,其中8个沿拱形分布,质量约2-16 M☉,维里参数约0.3-5,支持触发恒星形成机制。

Comments 16 pages, 14 figures

Journal ref A&A 709, A173 (2026)

详情
AI中文摘要

多项理论和观测研究表明,由于H II区的膨胀,新形成的巨大原恒星的反馈可以引发新一波触发恒星形成。我们利用ALMAGAL巡天的毫米尘埃连续谱数据和Anderson等人2014年的H II区星表,选择了一个ALMAGAL源进行ALMA后续观测。事实上,在源AG286.0716$-$1.8229中,在$\sim7600$ au分辨率下探测到6个核,但在更高分辨率下只有2个。未在更高分辨率下探测到的4个核是前恒星核候选体。我们利用SMGPS和RACS的档案数据确认该区域是否存在H II区。我们用ALMA在Band 4观测了该源,覆盖了DCO$^+$ (2$-$1)、N$_2$D$^+$ (2$-$1)、DCN (2$-$1)和CH$_3$CCH (9$-$8)的发射,以估计这些核是否处于恒星形成过程的早期阶段。新的Band 4连续谱图像揭示了ALMAGAL视场外的三个核,该区域共有9个核,其中8个位于半径$\sim0.75$ pc的拱形上。对于候选H II区,我们在0.8-1.6 GHz频率范围内推导出谱指数在-0.14到-0.4之间,这与光学薄自由-自由发射一致。利用基于化学示踪物和尘埃连续谱信息的合理温度范围,我们推导出核的质量范围($\sim2-16\,$M$_{\odot}$)和维里参数范围($\sim0.3-5$)。沿拱形分布的所有核的维里参数均$\lesssim$2,只有一个例外。将核的典型间距和质量与收集坍缩情景中预期的以及热金斯长度和质量进行比较,发现与触发恒星形成情况下的特征尺度最吻合。

英文摘要

Several theoretical and observational studies have shown that new waves of triggered star-formation can be induced by the feedback from newly formed massive protostars, due to the expansion of H II regions. We used the millimeter dust continuum data of the ALMAGAL survey and the Anderson et al. 2014 catalog of H II regions and selected one ALMAGAL source for ALMA follow-up observations. In fact, in source AG286.0716$-$1.8229 six cores were detected at a resolution of $\sim7600$ au, but only two at a higher resolution. The 4 cores not detected at higher resolution are prestellar core candidates. We used archival data from the SMGPS and RACS to confirm whether an H II region is present in the field. We observed the source with with ALMA in Band 4, covering the emission of DCO$^+$ (2$-$1), N$_2$D$^+$ (2$-$1), DCN (2$-$1), and CH$_3$CCH (9$-$8), to estimates whether these cores are in an early phase of the star-formation process. The new Band 4 continuum image revealed three cores outside of the ALMAGAL field of view, for a total of 9 cores in the region, 8 of which are located along an arch of radius $\sim0.75$ pc. We have derived a spectral index between -0.14 and -0.4, in the frequency range of 0.8-1.6 GHz for the candidate H II region, which is consistent with optically thin free-free emission. Using plausible temperature ranges, based on the information from chemical tracers and the dust continuum, we derived mass ranges for the cores ($\sim2-16\,$M$_{\odot}$) and ranges for the virial parameter ($\sim0.3-5$). All the cores along the arch have virial parameters $\lesssim$2, with only one exception. Comparing the typical separation and mass of the cores with those expected in the case of the collect and collapse scenario and with the thermal Jean length and mass, the best agreement is found with the characteristic scales in the case of triggered star formation.

2401.08883 2026-05-27 math.AT math.GN math.GT

On R-trees, homotopies, and covering maps

关于R-树、同伦和覆叠映射

Jeremy Brazas, Gregory R. Conner, Paul Fabel, Curtis Kent

AI总结 本文证明若群作用在R-树上使得商映射具有唯一道路提升性质,则商空间不含圆盘,进而推出具有该性质的流形映射必为覆叠映射,并发现同伦等价关系可由一维回溯生成。

Comments 18 pages, 5 page appendix, 6 figures

Journal ref Pacific J. Math. 343 (2026) 315-341

详情
AI中文摘要

映射 $p:E\\to X$ 具有 \\emph{唯一道路提升} 性质,如果 $X$ 中的每条道路,在选定起点后,唯一地提升为 $E$ 中的一条道路。我们证明,如果群 $G$ 作用在 $\\\mathbb R$-树 $T$ 上,使得商映射 $p: T\\to T/G$ 具有唯一道路提升性质,那么商空间 $T/G$ 不包含圆盘。作为推论,我们证明每个具有唯一道路提升性质的流形映射都是覆叠映射。证明需要对道路中的一维回溯进行研究。我们展示了一个令人惊讶且反直觉的结果:由道路的相对端点同伦给出的等价关系是由插入和删除一维回溯生成的。

英文摘要

A map $p:E\to X$ has the \emph{unique path lifting} property if every path in $X$, after a choice of an initial point, lifts uniquely to a path in $E$. We prove that if a group $G$ acts on an $\mathbb R$-tree $T$ such that the quotient map $p: T\to T/G$ has the unique path lifting property, then the quotient space $T/G$ does not contain a disc. As a consequence, we show that every map of manifolds with the unique path lifting property is a covering map. The proof requires a study of one-dimensional backtracking in paths. We show the surprising and counterintuitive result that the equivalence relation given by homotopies of paths rel. endpoints is generated by inserting and deleting one-dimensional backtracking.

2604.05665 2026-05-27 astro-ph.GA

Higher resolution optical spectra of $M_*<10^{10}~M_{\odot}$ galaxies reveal outflow signatures unresolved by the SDSS

$M_*<10^{10}~M_{\odot}$ 星系的高分辨率光学光谱揭示了 SDSS 未分辨的流出特征

B. Hagedorn, C. Cicone, C. Vignali, P. Severgnini, M. Pedani, M. Sarzi, A. Saintonge, M. Romano

AI总结 利用中高分辨率光学光谱,在低质量恒星形成星系中检测到约30%的星系存在电离气体流出,证实了SDSS光谱因分辨率不足而遗漏了这些流出信号。

Comments Accepted for publication in A&A. 21 pages, 16 figures

Journal ref A&A 709, A242 (2026)

详情
AI中文摘要

理论预测星系流出在低质量星系中普遍存在,但观测证据不足。低信噪比和低光谱分辨率会严重阻碍星系流出的探测,尤其是在具有本征窄谱线的小星系中。我们利用TNG/DOLORES和NTT/EFOSC2仪器,获得了52个局域恒星形成星系($0.01 < z < 0.03$,恒星质量$10^{8.5}<M_*/[M_{\odot}]<10^{10}$)的新中高分辨率(FWHM$_\mathrm{inst}\sim50-110$ km/s)光学光谱。我们的母样本由具有可用外差单碟分子(即CO)谱线数据的SDSS星系组成。本研究的目标是从那些基于CO线宽、SDSS光谱分辨率和相应的SDSS Hα线宽比较,有很高概率未被SDSS光谱分辨的星系中选出。我们的新光谱揭示了整体更窄的Hα和[OIII]$\lambda5007$线,并带有不对称性和宽翼,这些特征在相同星系的SDSS光谱中不存在。这证实了SDSS光谱未能分辨低$M_*$星系的窄发射线,从而阻碍了流出的探测。基于Hα线光谱,我们在约30%的目标中识别出流出特征。假设典型的双锥流出几何结构,该探测率与低质量区域普遍存在流出的理论预测一致。对于样本中恒星形成率高于平均水平(SFR $>10^{-0.74}~\mathrm{M_{\odot}/yr}$)的星系,流出发生率增强(约60%)。我们估计电离气体质量流出率范围约为$\sim0.1-50\times10^{-3}~\mathrm{M_{\odot}/yr}$(均值$\sim20\times10^{-3}~\mathrm{M_{\odot}/yr}$),相应的质量加载因子在0.03到0.14之间(均值$\sim0.07$)。

英文摘要

Galactic outflows are predicted to be ubiquitous in low-mass galaxies, but observational evidence is lacking. Both a low signal-to-noise and a low spectral resolution can severely hamper the detection of galactic outflows, especially in small galaxies that have intrinsically narrow spectral lines. We obtained new, medium-high resolution (FWHM$_\mathrm{inst}\sim50-110$~km/s) optical spectra of 52 local star forming galaxies ($0.01 < z < 0.03$) with stellar masses $10^{8.5}<M_*/[M_{\odot}]<10^{10}$, using the TNG/DOLORES and NTT/EFOSC2 instruments. Our parent sample consists of SDSS galaxies with available heterodyne single-dish molecular (i.e., CO) line data. The targets of this study are selected among those that, based on the comparison between CO line widths, SDSS spectral resolution, and corresponding SDSS-based H$α$ line widths, have a high chance of being unresolved by SDSS spectroscopy. Our new, spectra reveal overall narrower H$α$ and [OIII]$\lambda5007$ lines, with signs of asymmetries and broad wings that are absent in the SDSS spectra of the same galaxies. This confirms that SDSS spectroscopy does not resolve the narrow emission lines of low-M$_*$ galaxies, which hinders the detection of outflows. We identify outflow signatures in $\sim30\%$ of our targets based on the H$α$ line spectra. Assuming a typical bi-conical outflow geometry, this detection rate is consistent with theoretical predictions of ubiquitous outflows in the low-mass regime. The outflow incidence is enhanced ($\sim60\%$) for galaxies with above average star formation rates for the sample (SFR $>10^{-0.74}~\mathrm{M_{\odot}/yr}$). We estimate ionized gas mass outflow rates ranging from $\sim0.1-50\times10^{-3}~\mathrm{M_{\odot}/yr}$ (mean $\sim20\times10^{-3}~\mathrm{M_{\odot}/yr}$) and corresponding mass loading factors between 0.03 and 0.14 (mean $\sim0.07$) for the sample.

2603.26560 2026-05-27 astro-ph.CO gr-qc

Exploring the interplay of late-time dynamical dark energy and new physics before recombination

探索晚期动力学暗能量与复合前新物理的相互作用

Alex González-Fuentes, Adrià Gómez-Valent

AI总结 通过加权函数回归方法重建背景暗能量函数,研究复合前新物理对哈勃常数张力和晚期动力学暗能量信号的影响,发现幻影分裂概率高达96.7-98.5%,但早期新物理模型在解释SH0ES测量时面临物质密度参数冲突。

Comments 37 pages, 6 figures, 7 tables. Added references and comments. Accepted for publication in JCAP

详情
AI中文摘要

表现出幻影分裂的宇宙学模型改进了对当前数据的拟合,表明晚期暗能量动力学在约3σ置信水平。然而,它们倾向于较低的H0值,与SH0ES存在张力。这可能指向退耦时代之前存在新物理。在这项工作中,我们使用加权函数回归方法重建背景暗能量函数,与我们之前的JCAP 12 (2025) 049相比引入了三个主要改进。首先,我们采用频率-贝叶斯方法确定权重。其次,我们将CMB和BAO与DES-Dovekie SNIa样本结合,并将我们的发现与使用Pantheon+(仍假设标准复合)的结果进行比较。第三,我们以模型无关的方式研究早期“解决方案”对哈勃张力的可行性,以及它们如何影响晚期动力学暗能量的证据,分别考虑SH0ES和更保守的CCHP宇宙阶梯校准的影响。我们发现,如果复合前的物理未修改,幻影分裂的概率约为96.7-98.5%,ΛCDM在约2.5σ和约3σ置信水平被排除。复合前的新物理可以缓解哈勃张力,但当使用SH0ES校准时,需要极大值的约化物质密度参数,与全CMB分析推断的结果存在强烈张力。这引发了对这些模型实际解释SH0ES测量能力的严重担忧。我们发现,幻影分裂虽未被排除,但不再需要,仅对quintessence有非常轻微偏好。然而,鉴于上述ωm中的张力,就这些情景中动力学暗能量信号如何受影响得出明确结论将是草率的。[删节]

英文摘要

Cosmological models exhibiting crossing of the phantom divide improve the fit to current data, suggesting late-time dark energy (DE) dynamics at $\sim3σ$ CL. However, they favor low values of $H_0$, in tension with SH0ES. This may point to the presence of new physics prior to the decoupling era. In this work, we reconstruct the background DE functions using the Weighted Function Regression (WFR) method, introducing three main improvements compared to our previous JCAP 12 (2025) 049. First, we adopt the Frequentist-Bayesian approach for the weights. Second, we combine CMB and BAO with the DES-Dovekie SNIa sample and compare our findings with those derived from Pantheon+, still assuming standard recombination. Third, we study in a model-independent manner the viability of early-time ``solutions'' to the Hubble tension and how they affect the evidence for dynamical DE at late times, under the influence of the SH0ES and the more conservative CCHP calibration of the cosmic ladders, separately. We find that, if the physics prior to decoupling is unmodified, the probability of phantom crossing is $\sim 96.7\text{--}98.5\%$, with $Λ$CDM excluded at $\sim 2.5σ$ and $\sim 3σ$ CL. New physics before recombination can alleviate the Hubble tension, but requires extremely large values of the reduced matter density parameter when the SH0ES calibration is employed, in strong tension with those inferred from full CMB analyses. This raises serious concerns about the actual viability of these models to explain the SH0ES measurement. We find that phantom crossing, while not excluded, is no longer required, with only a very mild preference for quintessence. Nevertheless, given the aforesaid tension in $ω_m$, it would be rash to draw firm conclusions about how the dynamical DE signal is affected in these scenarios. [abridged]

2510.11626 2026-05-27 astro-ph.GA astro-ph.IM

JADES Dark Horse: demonstrating high-multiplex observations with JWST/NIRSpec dense-shutter spectroscopy in the JADES Origins Field

JADES Dark Horse: 在JADES起源场中使用JWST/NIRSpec密集快门光谱进行高多路复用的观测演示

Francesco D'Eugenio, Erica J. Nelson, Daniel J. Eisenstein, Roberto Maiolino, Stefano Carniani, Jan Scholtz, Mirko Curti, Christopher N. A. Willmer, Andrew J. Bunker, Jakob M. Helton, Ignas Juodžbalis, Fengwu Sun, Sandro Tacchella, Santiago Arribas, Alex J. Cameron, Stéphane Charlot, Emma Curtis-Lake, Kevin Hainline, Benjamin D. Johnson, Brant Robertson, Christina C. Williams, Chris Willott, William M. Baker, Jacopo Chevallard, A. Lola Danhaive, Yuki Isobe, Xihan Ji, Zhiyuan Ji, Gareth C. Jones, Nimisha Kumari, Tobias J. Looser, Jianwei Lyu, Eleonora Parlanti, Michele Perna, Dávid Puskás, Pierluigi Rinaldi, Charlotte Simmonds, Yang Sun, Hannah Übler, Giacomo Venturi, Joris Witstok, Zihao Wu, Yongda Zhu

AI总结 提出JWST/NIRSpec密集快门光谱(DSS)策略,通过控制光谱重叠实现高多路复用,在JADES起源场中观测约850个源,获得约540个星系的光谱红移,目标密度比标准MSA策略高4-5倍,线灵敏度在固定曝光时间下降低30%但巡天速度提升5倍。

Comments 22 pages, 21 figures, 2 tables. Published in MNRAS

Journal ref Mon Not R Astron Soc (2026)

详情
AI中文摘要

我们展示了JWST/NIRSpec密集快门光谱(DSS)。这种使用NIRSpec/MSA的新颖观测策略故意允许大量受控的光谱重叠,以达到极高的多路复用,同时保持狭缝光谱的低背景。在JADES起源场的一个单一配置中,我们打开了所有暗弱(mF444W$<$30 mag)z$_\mathrm{phot}>$3候选体的快门,优先考虑发射线科学,仅拒绝明亮的连续谱源。使用G235M和G395M的33.6 ks和35.8 ks曝光时间,我们观测了一个包含约850个源的单一掩模,获得了约540个星系在2.5$<$z$<$8.9范围内的光谱红移。DSS模式下每配置的目标密度是标准无重叠和低重叠MSA策略(<200个源)的4-5倍,且红移精度或准确度没有损失。在固定曝光时间下,线灵敏度降低30%,与预期的背景噪声增加相匹配,但在我们的设置中巡天速度提升5倍,完全证明了这一代价的合理性。测得的线灵敏度在λ~4 μm处比NIRCam/WFSS至少高约5倍(曝光时间约25倍),表明DSS是一种获取大样本深宽波段光谱的引人注目的方法。关键的是,NIRSpec/MSA可以实现比这里使用的更高的目标分配密度。我们推导了基于Hα的恒星形成率、气相金属丰度(包括适合强线校准的大样本),并识别了稀有的迷你淬灭星系和宽线活动星系核。DSS可立即应用于深场成像能够实现稳健预选和天体测量的任何地方,提供了一种获取大量暗弱发射线星系样本的高效方法,是无缝巡天的完整性与NIRSpec/MSA的灵敏度和带宽之间的一个引人注目的中间地带。

英文摘要

We present JWST/NIRSpec dense-shutter spectroscopy (DSS). This novel observing strategy with the NIRSpec/MSA deliberately permits a high number of controlled spectral overlaps to reach extreme multiplex while retaining the low background of slit spectroscopy. In a single configuration over the JADES Origins Field, we opened shutters on all faint (mF444W$<$30 mag) z$_\mathrm{phot}>$3 candidates, prioritising emission-line science and rejecting only bright continuum sources. Using 33.6 and 35.8 ks on-source in G235M and G395M, we observed a single mask with $\sim$850 sources, obtaining spectroscopic redshifts for $\sim$540 galaxies over 2.5$<$z$<$8.9. The per-configuration target density in DSS mode is 4-5x higher than standard no- and low-overlap MSA strategies ($<$200 sources), with no loss in redshift precision or accuracy. Line-flux sensitivities are 30 percent lower at fixed exposure time, matching the expected increase in background noise, but the gain in survey speed is 5x in our setup, more than justifying the penalty. The measured line sensitivity exceeds NIRCam/WFSS by at least $\sim$5x ($\sim$25x in exposure time) at $λ\sim4\,μ$m, demonstrating that DSS is a compelling method to gain deep, wide-band spectra for large samples. Crucially, NIRSpec/MSA could deliver even higher target allocation densities than those used here. We derive H$α$-based SFRs, gas-phase metallicities (including a large sample suitable for strong-line calibrations), and identify rare mini-quenched galaxies and broadline AGN. DSS is immediately applicable wherever deep imaging enables robust pre-selection and astrometry, providing an efficient method to obtain large samples of faint emission-line galaxies, a compelling middle ground between the completeness of slitless surveys and the sensitivity and bandwidth of NIRSpec/MSA.

2602.05368 2026-05-27 astro-ph.CO gr-qc

Dark Energy After DESI DR2: Observational Status, Reconstructions, and Physical Models

DESI DR2后的暗能量:观测状态、重构与物理模型

Slava G. Turyshev

AI总结 基于DESI DR2数据,结合Ia超新星、各向异性BAO、CMB校准及扰动敏感探针,评估了暗能量演化证据,并提供了两种诊断工具和从现象学到微观物理模型的映射。

Comments 26 pages, 3 figures, 5 tables

Journal ref Phys. Rev. D 113, 103540 (2026)

详情
AI中文摘要

我们回顾了DESI数据发布2(DR2)后的晚期宇宙加速,强调了Ia型超新星(SNe Ia)、各向异性BAO、CMB校准以及扰动敏感探针(RSD和弱引力透镜)之间的相互作用。DESI DR2提供了在$0\lesssim z\lesssim2.5$范围内百分水平的BAO距离比,包括在$z_{\rm eff}=2.33$处的Ly$\alpha$森林锚点。在CMB校准的组合中,平坦$\Lambda$CDM表现出轻微的参数不匹配,而允许暗能量演化(例如CPL $w_0$--$w_a$)可以改善拟合;这种偏好依赖于数据集,并且对红移相关的超新星校准/选择残差特别敏感,残差在几个$\times10^{-2}$星等水平。为了增强似然水平的解释,我们提供了两种诊断:(i)一个与$r_d$无关的BAO形状可观测量$F_{\rm AP}(z)\equiv D_{\rm M}(z)/D_{\rm H}(z)$,直接从已发布的$(D_{\rm M}/r_d,\,D_{\rm H}/r_d)$通过协方差传播构建;以及(ii)一个从超新星哈勃图系统误差$\delta\mu(z)$到$(w_0,w_a)$诱导偏差的线性响应映射,为DESI时代声称的$w(z)$演化提供了明确的校准要求。我们综合了$w(z)$和$\rho_{\rm DE}(z)$的参数化和非参数化重构,并将所得现象学映射到受扰动稳定性和引力波传播约束的微观物理暗能量和修正引力模型。

英文摘要

We review late-time cosmic acceleration after DESI Data Release 2 (DR2), emphasizing the interplay between Type Ia supernovae (SNe Ia), anisotropic BAO, CMB calibration, and perturbation-sensitive probes (RSD and weak lensing). DESI DR2 delivers percent-level BAO distance ratios over $0\lesssim z\lesssim2.5$, including a Ly$α$-forest anchor at $z_{\rm eff}=2.33$. In CMB-calibrated combinations, flat $Λ$CDM exhibits a mild parameter mismatch, while allowing evolving dark energy (e.g.\ CPL $w_0$--$w_a$) can improve the fit; the preference is dataset-dependent and is particularly sensitive to redshift-dependent SN calibration/selection residuals at the few$\times10^{-2}$\,mag level. To sharpen likelihood-level interpretation, we provide two diagnostics: (i) an $r_d$-independent BAO-shape observable, $F_{\rm AP}(z)\equiv D_{\rm M}(z)/D_{\rm H}(z)$, constructed directly from published $(D_{\rm M}/r_d,\,D_{\rm H}/r_d)$ with covariance propagation; and (ii) a linear-response map from SN Hubble-diagram systematics $δμ(z)$ to induced biases in $(w_0,w_a)$, yielding an explicit calibration requirement for DESI-era claims of evolving $w(z)$. We synthesize parametric and non-parametric reconstructions of $w(z)$ and $ρ_{\rm DE}(z)$ and map the resulting phenomenology to microphysical dark-energy and modified-gravity models subject to perturbation stability and gravitational-wave propagation constraints.

2512.15028 2026-05-27 cs.DC cs.NI cs.OS cs.PF

Reexamining Paradigms of End-to-End Data Movement

重新审视端到端数据传输的范式

Chin Fang, Timothy Stitt, Michael J. McManus, Toshio Moriya

AI总结 本文通过引入流域模式概念模型,系统分析网络延迟、TCP拥塞控制、主机CPU性能等六大范式对端到端数据传输的影响,并通过生产级部署验证了瓶颈常位于网络核心之外,强调软硬件协同设计可实现可预测的高性能数据传输。

Comments 33 pages and 15 figures

详情
AI中文摘要

追求高性能数据传输往往聚焦于原始网络带宽。100 Gbps或更高的国际链路常被视为主要推动力。虽然必要,但这种以网络为中心的观点是不完整的。它将配置的链路速度等同于实际、可持续的数据传输能力。一个常见的观察是,即使在10 Gbps链路上也会出现低于期望的数据速率,而更高速的网络只会放大其可见性。我们研究了六个范式——从网络延迟和TCP拥塞控制到主机侧因素如CPU性能和虚拟化——它们对数据传输工作流产生关键影响。这些范式代表了广泛接受的工程假设,这些假设指导着生产数据传输环境中的系统设计、采购决策和操作实践。我们引入了流域模式概念模型,用于推理跨异构硬件和软件组件在不同期望数据速率下的端到端数据流约束,以解决原始带宽与应用层吞吐量之间的保真度差距。我们的发现通过严格的生产级部署得到验证,从10 Gbps链路到美国DOE ESnet技术评估以及超过100 Gbps运营链路的跨大陆生产试验。结果表明,主要瓶颈通常位于网络核心之外,而整体的软硬件协同设计能够为要求苛刻的数据传输(批量与流式)实现一致、可预测的性能。关键目标是将要求苛刻的数据传输从一场结果未知的斗争转变为一种可预测、保证线速、任何人都能执行的常规操作。另一个目标是纠正将复杂性与专业知识混为一谈的普遍误解。

英文摘要

The pursuit of high-performance data transfer often focuses on raw network bandwidth. International links of 100 Gbps or higher are frequently considered the primary enabler. While necessary, this network-centric view is incomplete. It equates provisioned link speeds with practical, sustainable data movement capabilities. It is a common observation that lower-than-desired data rates manifest even on 10 Gbps links, with higher-speed networks only amplifying their visibility. We investigate six paradigms -- from network latency and TCP congestion control to host-side factors such as CPU performance and virtualization -- that critically impact data movement workflows. These paradigms represent widely accepted engineering assumptions that inform system design, procurement decisions, and operational practices in production data movement environments. We introduce the Drainage Basin Pattern conceptual model for reasoning about end-to-end data flow constraints across heterogeneous hardware and software components at varying desired data rates to address the fidelity gap between raw bandwidth and application-level throughput. Our findings are validated through rigorous production-scale deployments, from 10 Gbps links to U.S. DOE ESnet technical evaluations and transcontinental production trials over 100 Gbps operational links. The results demonstrate that principal bottlenecks often reside outside the network core, and that a holistic hardware-software co-design enables consistent, predictable performance for demanding data transports (bulk and streaming). The key goal is to transform a demanding data transfer from a struggle with unknown outcomes into a predictable, guaranteed line-rate, routine operation that anyone can do. Another goal is to rectify the general misconception that conflates complexity with expertise.

2508.16444 2026-05-27 stat.AP

Dynamic Financial Analysis (DFA) of General Insurers under Climate Change

气候变化下一般保险公司的动态财务分析(DFA)

Benjamin Avanzi, Yanfeng Li, Greg Taylor, Bernard Wong

AI总结 针对传统DFA未考虑气候变化影响的问题,提出一个扩展的DFA框架,通过整合物理和经济维度的气候风险,实现对一般保险行业长期影响的整体评估,并以澳大利亚数据实证展示了其优势。

详情
AI中文摘要

预计气候变化将在长期内显著影响物理、金融和经济环境,对一般保险公司的财务健康构成风险。尽管一般保险公司通常使用动态财务分析(DFA)来全面了解财务影响,但文献中传统的DFA并未考虑气候变化的影响。为弥补这一空白,我们将静态DFA框架扩展以整合气候风险,从而能够整体评估气候变化对一般保险行业的长期影响,并为单个保险公司的DFA提供基础架构。我们的框架通过在一个互联结构中考虑不同气候情景下的物理和经济维度,捕捉气候变化对一般保险公司资产和负债的长期影响。此外,它通过气候情景分析中的随机模拟处理气候变化影响的不确定性,这对精算应用非常有用。我们的扩展针对一般保险部门量身定制,并解决了其独特特征。为展示模型的实际应用,我们使用澳大利亚数据进行了广泛的实证研究,评估了不同气候情景下气候变化对一般保险市场的长期财务影响。结果与静态DFA框架的结果进行了基准比较,表明经济增长与物理风险之间的相互作用在塑造一般保险公司的风险-回报特征中起着关键作用。它们突出了在气候变化影响下,气候依赖型DFA相比静态DFA在生成财务预测方面的优势。我们充分讨论了框架的局限性。

英文摘要

Climate change is expected to significantly affect the physical, financial, and economic environments over the long term, posing risks to the financial health of general insurers. While general insurers typically use Dynamic Financial Analysis (DFA) for a comprehensive view of financial impacts, traditional DFA as presented in the literature does not consider the impact of climate change. To address this gap, we extend the stationary DFA framework to integrate climate risk, enabling a holistic assessment of the long-term impact of climate change on the general insurance industry and offering a foundational architecture for the DFA of individual insurers. Our framework captures the long-term impact of climate change on the assets and liabilities of general insurers by considering both physical and economic dimensions across different climate scenarios within an interconnected structure. Furthermore, it addresses the uncertainty of climate change impacts using stochastic simulations within climate scenario analysis that are useful for actuarial applications. Our extensions are tailored to the general insurance sector and address its unique characteristics. To demonstrate the practical application of our model, we conduct an extensive empirical study using Australian data and assess the long-term financial impact of climate change on the general insurance market under various climate scenarios. The results are benchmarked against those of a stationary DFA framework and show that the interaction between economic growth and physical risk plays a key role in shaping general insurers' risk-return profiles. They highlight the advantages of the climate-dependent DFA over the stationary DFA in generating financial projections under climate change impacts. Limitations of our framework are thoroughly discussed.

2604.01698 2026-05-27 physics.acc-ph astro-ph.IM

High-power Test and System Integration of Direct RF Sampling Based LLRF Control and Monitoring System for S-Band Accelerating Structures

基于直接射频采样的S波段加速结构低电平控制与监测系统的高功率测试与系统集成

Chao Liu, Ankur Dhar, Michael Hoganson, Emilio Nanni, Joseph Olszewski, Emma Snively, Sophia Morton, Thi Le, Wei-Hou Tan

AI总结 本文开发了基于RFSoC的直接射频采样LLRF系统,用于S波段加速结构,并通过高功率测试和系统集成验证了其性能优于传统方案。

详情
AI中文摘要

未来粒子加速器的高精度低电平射频(LLRF)控制与监测系统将面临性能、灵活性和经济性要求日益严格的重大技术挑战。我们开发了基于射频片上系统(RFSoC)的下一代LLRF(NG-LLRF)系统,用于S波段加速结构,该系统直接采样和合成射频脉冲,无需传统LLRF系统中使用的模拟混频器。该平台的性能显著优于目标应用的要求,例如下一代直线对撞机测试加速器(NLCTA)和SLAC测试设施的升级。作为升级计划的一部分,我们还开发了定制固态放大器(SSA),以提供速调管所需功率水平的射频脉冲。LLRF与SSA及高功率测试设施的集成可能具有挑战性。必须优化高功率射频驱动系统各级的功率水平和射频脉冲稳定性,以实现所需的射频性能。本文将总结、分析和讨论集成过程以及各集成阶段的测试与表征结果。该集成是NG-LLRF系统在不同频段的测试设施和加速器中全面部署的关键步骤。

英文摘要

High precision Low-level RF (LLRF) control and monitoring systems for future particle accelerators will be a significant technical challenge as the requirements in performance, flexibility and affordability become increasingly stringent. We have developed an RF system-on-chip (RFSoC) based next-generation LLRF (NG-LLRF) for S-band accelerating structures, which samples and synthesizes the RF pulses directly without the analog mixers used for traditional LLRF systems. The platform delivered considerably better performance than the requirements of the targeted applications, such as the upgrades for Next Linear Collider Test Accelerator (NLCTA) and test facilities at SLAC. As part of the upgrade program, we also developed a custom solid-state amplifier (SSA) to deliver RF pulses at the desired power level of the klystron. Integration of the LLRF with the SSA and the high-power test facility could be challenging. The power levels and RF pulse stability at each stage of the high-power RF drive system must be optimized to deliver the desired RF performance. In this paper, the integration procedure and the test and characterization results at each stage of integration will be summarized, analyzed and discussed. This integration is an essential step for the full deployment of the NG-LLRF system to test facilities and accelerators in different frequency bands.

2401.14996 2026-05-27 cs.LO

A Resolution-Based Interactive Proof System for UNSAT

基于消解的可交互证明系统用于不可满足性

Philipp Czerner, Javier Esparza, Valentin Krasotin, Adrian Krauss

AI总结 本文通过将交互式证明系统与消解过程结合,提出了首个针对Davis-Putnam消解过程的交互协议,并证明了寻找竞争性交互协议可归结为寻找满足交换性质的公式算术化问题。

Journal ref Logical Methods in Computer Science, Volume 22, Issue 2 (May 22, 2026) lmcs:14454

详情
AI中文摘要

现代SAT或QBF求解器预期产生正确性证书。然而,证书在最坏情况下具有指数级大小(除非NP=coNP),在最近的SAT竞赛中,最大的不可满足性证书已开始达到TB级别。这限制了SAT求解服务的发展,其中计算能力有限的客户端将公式发送到运行在强大服务器上的求解器,求解器返回证书供客户端检查。最近,Couillard等人建议用基于IP=PSPACE定理的交互式证明系统替代证书。他们提出了一个证明者和验证者之间的交互协议,用于QBF的扩展。该协议的总运行时间与标准BDD算法所需时间成线性关系,而验证者投入的时间与公式大小成多项式关系。(因此,特别地,验证者永远不必读取或处理指数级长的证书)。我们称这种交互协议在求解QBF方面与BDD算法具有竞争性。虽然BDD算法对于某些类别的QBF实例是最先进的,但现代(UN)SAT求解器并不基于BDD。为此,我们开始研究更实用SAT算法的交互式认证。特别地,我们探讨交互协议是否能够与某种消解变体具有竞争性。我们提出两个贡献。首先,我们证明了一个定理,将寻找竞争性交互协议的问题归结为寻找满足某些交换性质的公式算术化问题。(算术化是IP=PSPACE定理背后的基本技术。)然后,我们应用该定理给出了首个针对Davis-Putnam消解过程的交互协议。我们还报告了实现情况并给出了一些实验结果。

英文摘要

Modern SAT or QBF solvers are expected to produce correctness certificates. However, certificates have worst-case exponential size (unless NP=coNP), and at recent SAT competitions the largest certificates of unsatisfiability are starting to reach terabyte size. This puts limits to the development of SAT-solving services in which a client with limited computational power sends a formula to a solver running on a powerful server, which returns a certificate to be checked by the client. Recently, Couillard et al. have suggested to replace certificates with interactive proof systems based on the IP=PSPACE theorem. They have presented an interactive protocol between a prover and a verifier for an extension of QBF. The overall running time of the protocol is linear in the time needed by a standard BDD-based algorithm, and the time invested by the verifier is polynomial in the size of the formula. (So, in particular, the verifier never has to read or process exponentially long certificates). We call such an interactive protocol competitive with the BDD algorithm for solving QBF. While BDD algorithms are state-of-the-art for certain classes of QBF instances, no modern (UN)SAT solver is based on BDDs. For this reason, we initiate the study of interactive certification for more practical SAT algorithms. In particular, we address the question whether interactive protocols can be competitive with some variant of resolution. We present two contributions. First, we prove a theorem that reduces the problem of finding competitive interactive protocols to finding an arithmetisation of formulas satisfying certain commutativity properties. (Arithmetisation is the fundamental technique underlying the IP=PSPACE theorem.) Then, we apply the theorem to give the first interactive protocol for the Davis-Putnam resolution procedure. We also report on an implementation and give some experimental results.

2604.00946 2026-05-27 astro-ph.EP

Near-Earth asteroids in Main Belt-crossing orbits

主带穿越轨道上的近地小行星

P. S. Zain, R. P. Di Sisto, R. Gil-Hutton

AI总结 通过N体模拟和碰撞演化模型,研究了主带穿越轨道上的近地小行星的动力学与碰撞演化,揭示了其轨道寿命、主带驻留时间分布及碰撞对表面和总体大小频率分布的影响。

Comments Accepted by Astronomy&Astrophysics

Journal ref A&A 709, A261 (2026)

详情
AI中文摘要

我们研究了主带穿越轨道上的近地小行星(NEACs)的动力学和碰撞演化。我们选取H < 18的NEACs,并通过N体模拟积分其轨道至1e7年。根据初始半长轴将目标分组(G1: a < 2.06 au; G2: 2.06 < a < 2.5 au; G3: a > 2.5 au)。我们计算了每个轨道在主带内停留的时间比例、(a,e)平面上的动力学占据图以及中位寿命。通过碰撞演化,我们获得了与大小相关的时间尺度、1 Myr内NEA大小频率分布(SFD)的变化,以及150 m至1 km目标(代表空间任务访问的NEAs)上的撞击体和坑SFD。中位动力学寿命随a增加而减小:~1.3e7年(G1)、~2.1e6年(G2)和~0.9e6年(G3)。G2-G3中的NEACs保持几乎恒定的主带驻留比例,且完全包含在主带内的间隔较短,而G1表现出更强的0-0.8振荡(中位约0.55,持续约1e6年)。对于小于约300 m的目标,DART类似撞击发生在约1e5年时间尺度上(对于更大天体升至约1e6年),而灾难性碰撞在NEAC寿命内可忽略。在1 Myr内,碰撞侵蚀使米级NEA种群减少仅0.1-1.4%,具体取决于Q_D*。与Bennu、Didymos和Ryugu上观测到的坑SFD比较表明,Bennu的目标强度Y ~ 100 Pa,Didymos具有年轻的有效表面年龄,而Ryugu上直径小于100 m的坑的短坑保留时间约为1e4-1e5年,与快速表面更新一致。NEACs在其寿命的相当一部分时间内位于主带内部,并经历频繁的小规模撞击,但碰撞在Myr时间尺度上对全球NEA SFD的修改较弱。我们的动力学-碰撞联合框架约束了NEAC的寿命、轨道路径、碰撞时间尺度和表面处理过程。

英文摘要

We study the dynamical and collisional evolution of Near-Earth asteroids (NEAs) in Main Belt-crossing orbits (NEACs). We select NEACs with H < 18 and integrate their orbits for 1e7 yr with N-body simulations. Objects are grouped by initial semi-major axis (G1: a < 2.06 au; G2: 2.06 < a < 2.5 au; G3: a > 2.5 au). We compute the fraction of each orbit spent within the main belt (MB), dynamical occupancy maps in the (a,e) plane, and median lifetimes. Using collisional evolution, we obtain size-dependent timescales, the change in the NEA size-frequency distribution (SFD) over 1 Myr, and impactor and crater SFDs on 150 m to 1 km targets, representative of NEAs visited by space missions. Median dynamical lifetimes decrease with increasing a: ~1.3e7 yr (G1), ~2.1e6 yr (G2), and ~0.9e6 yr (G3). NEACs in G2-G3 maintain nearly constant MB residence fractions with short intervals of full containment, while G1 exhibits stronger 0-0.8 oscillations (median ~0.55 for ~1e6 yr). DART-analog impacts occur on ~1e5 yr timescales for targets smaller than about 300 m (rising to ~1e6 yr for larger bodies), whereas catastrophic collisions are negligible within NEAC lifetimes. Over 1 Myr, collisional erosion reduces the meter-size NEA population by only 0.1-1.4% depending on Q_D*. Comparison with the observed crater SFDs on Bennu, Didymos, and Ryugu indicates target strengths of Y ~ 100 Pa for Bennu, young effective surface ages for Didymos, and short crater-retention times of order 1e4-1e5 yr for craters with diameters smaller than 100 m on Ryugu, consistent with rapid resurfacing. NEACs spend a substantial fraction of their lifetimes inside the MB and undergo frequent small-scale impacts, yet collisions weakly modify the global NEA SFD on Myr timescales. Our combined dynamical-collisional framework constrains NEAC lifetimes, orbital pathways, collisional timescales, and surface processing.

2604.00944 2026-05-27 cs.CY

Auditing the Reliability of Multimodal Generative Search

审计多模态生成式搜索的可靠性

Erfan Samieyan Sahneh, Luca Maria Aiello

AI总结 通过大规模审计Gemini 2.5 Pro系统,发现3.7%至18.7%的基于视频的生成式搜索声明未被引用来源支持,主要失败模式为不可验证的特异性与夸大声明。

Comments 14 pages, LaTeX, typos corrected, adding Data Availability section + examples in appendix, New plot(overview)

详情
AI中文摘要

多模态大语言模型(MLLMs)越来越多地充当生成式搜索系统,从多媒体内容(包括YouTube视频)中检索并综合答案。尽管这些系统通过引用特定视频作为证据来展现权威性,但这些引用在多大程度上真正证实了生成的声明仍未被充分探索。我们对Gemini 2.5 Pro多模态搜索系统进行了大规模审计,分析了在医疗、经济和通用领域生成的11,943个声明-视频对。通过使用三个独立的LLM评判者进行自动化验证(评分者间一致性87.7%),并基于人工标注进行验证,我们发现根据评判者的严格程度,3.7%至18.7%的基于视频的声明未被其引用来源支持。主要的失败模式并非直接矛盾,而是不可验证的特异性和夸大声明,这表明系统在引用视频作为证据的同时,从参数化知识中注入了精确但无根据的细节。通过逻辑回归进行的探索性事后分析揭示了与这些失败相关的属性:偏离源词汇的声明(β= -1.6至-3.1,p < 0.01)以及与视频转录语义相似度低的声明(β= -2.1至-11.6,p < 0.01)更可能不被支持。这些发现描述了当前基于视频的生成式搜索的可信度,并突显了这些系统展现的信心与其输出保真度之间的差距。数据集可在https://anonymous.4open.science/r/icwsm-gemini-audit-04DF获取。

英文摘要

Multimodal Large Language Models (MLLMs) increasingly function as generative search systems that retrieve and synthesize answers from multimedia content, including YouTube videos. Although these systems project authority by citing specific videos as evidence, the extent to which these citations genuinely substantiate the generated claims remains underexplored. We present a large-scale audit of the Gemini 2.5 Pro multimodal search system, analyzing 11,943 claim-video pairs generated across Medical, Economic, and General domains. Through automated verification using three independent LLM judges (87.7\% inter-rater agreement), validated against human annotations, we find that depending on the judge's strictness, between 3.7\% and 18.7\% of video-grounded claims are not supported by their cited sources. The dominant failure modes are not outright contradictions but rather unverifiable specificities and overstated claims, suggesting the system injects precise but ungrounded details from parametric knowledge while citing videos as evidence. Exploratory post-hoc analysis via logistic regression reveals properties associated with these failures: claims departing from source vocabulary ($β= -1.6$ to $-3.1$, $p < 0.01$) and claims with low semantic similarity to the video transcript ($β= -2.1$ to $-11.6$, $p < 0.01$) are significantly more likely to be unsupported. These findings characterize the current trustworthiness of video-based generative search and highlight the gap between the confidence these systems project and the fidelity of their outputs. The dataset is available at https://anonymous.4open.science/r/icwsm-gemini-audit-04DF .