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2604.20170 2026-06-11 hep-th gr-qc quant-ph 版本更新

Holographic Complexity, Extremality, and Cosmic Censorship

全息复杂性、极端性与宇宙审查

Fuat Berkin Altunkaynak

AI总结 提出全息复杂性解释黑洞力学第三定律和弱宇宙审查,发现次极端与极端黑洞的相对复杂性对数发散,阻止有限时间转变。

Comments 5 pages; v2: title changed, CV analysis and references added

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AI中文摘要

我们提出了黑洞力学第三定律和弱宇宙审查的全息复杂性起源。在复杂性等于作用和复杂性等于体积两种方案中,次极端与极端AdS黑洞之间的相对复杂性对数发散。对于过充电的RN-AdS,两种方案中的显式计算表明,近奇点作用项呈幂律发散或有限,而最大体积贡献是有限的。因此,极端到裸奇点的相对复杂性也发散,阻碍了有限时间转变。

英文摘要

We propose a holographic complexity origin for the third law of black-hole mechanics and weak cosmic censorship. In both complexity equals action and complexity equals volume prescriptions, the relative complexity between subextremal and extremal AdS black holes diverges logarithmically. For overcharged RN-AdS, explicit calculations in both prescriptions show that the near-singularity action terms are power-law divergent or finite, while the maximal-volume contribution is finite. Thus, the extremal-to-naked relative complexity also diverges, obstructing finite-time transitions.

2604.19867 2026-06-11 astro-ph.GA astro-ph.CO 版本更新

Hamilton's Object Revisited: A challenging source redshift of a strong lensing configuration

哈密顿天体的再审视:一个强透镜构型的挑战性源红移

Jenny Wagner, Emilio E. Falco

AI总结 通过重新分析蓝端凯克宇宙网络成像仪(KCWI)光谱,确认了强透镜星系Hamilton's Object的红移为z=0.82,排除了z=3.201的歧义,并指出MOIRCS光谱的不确定性。

Comments 9 pages, 5 figures, 2 tables, published in Astronomy & Astrophysics

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Journal ref
A&A, 710, A129 (2026)
AI中文摘要

低分辨率光谱仪在确定$z\approx1$和$z\approx3$的星系红移时曾遇到困难。镁和铁的光谱发射线和吸收线红移到$z\approx1$时,与$z\approx3$的氢、硅和氧线接近。这里我们证明,即使使用现代积分场单元光谱仪,这项任务仍然具有挑战性。Hamilton's Object是一个蓝色恒星形成星系,被星系团SDSS J223010.47-081017.8引力透镜成三个多重像,就是这样一个案例。使用蓝端凯克宇宙网络成像仪(KCWI),其红移被确定为$z=0.82$,而其MOIRCS光谱暗示$z=3.201$。为解决歧义,我们完全重新分析了所有三个多重像(包括外围恒星形成区)的蓝端KCWI光谱。我们采用了新的数据缩减管道PypeIt、信号增强和Python例程的线拟合。重新评估基于六个吸收特征确认了先前结果$z=0.820 \pm 0.001$,以及四个发射特征$z=0.821 \pm 0.002$。基于六个吸收线和两个发射线的备选$z=3.199\pm 0.003$拟合较差,与其他光谱相比也是如此。此外,我们发现MOIRCS光谱不确定:观测覆盖了三个多重像中的两个,像C的狭缝仅覆盖其中心核球;此外,由于缺少校准弧灯,像素到波长的校准需要夜天发射线校准。需要新的MOIRCS观测来验证Hamilton's Object在已知星系团尺度强透镜中具有透镜星系团和源星系之间角直径距离的最小间隔。

英文摘要

Low-resolution spectrographs used to have difficulties in determining redshifts of galaxies at $z\approx1$ and $z\approx3$. Spectral emission and absorption lines of magnesium and iron redshifted to $z\approx1$ fall close to hydrogen, silicon, and oxygen lines at $z\approx3$. Here, we demonstrate that even with modern, integrated field unit spectrographs, this task remains challenging. Hamilton's Object, a blue star-forming galaxy, gravitationally lensed into three multiple images by the galaxy cluster SDSS J223010.47-081017.8, is such a case. Using the Blue Keck Cosmic Web Imager (KCWI) its redshift was determined as $z=0.82$, while its MOIRCS spectrum hinted at $z=3.201$. To resolve the ambiguity, we completely reanalyse the Blue KCWI spectra of all three multiple images including the star-forming region in the outskirts. We employ a new data reduction pipeline, PypeIt, signal enhancement, and line fitting by Python-routines. The reevaluation confirms the previous result based on six absorption features, $z=0.820 \pm 0.001$, and four emission features, $z=0.821 \pm 0.002$. The alternative $z=3.199\pm 0.003$, based on six absorption and two emission lines, is a worse fit, also compared to other spectra. Moreover, we find the MOIRCS spectrum inconclusive: observations cover two of three multiple images, with the slit for image C only covering its central bulge; furthermore the pixel-to-wavelength calibration requires a nightsky emission-line calibration due to a missing calibration arc lamp. New MOIRCS observations are needed to verify that Hamilton's Object has the smallest separation in angular diameter distance between lensing cluster and source galaxy among the known cluster-scale strong lenses.

2604.19075 2026-06-11 astro-ph.GA astro-ph.CO 版本更新

What is Powering the Enigmatic He II Emitter Hebe: The First Stars or Black Holes?

是什么驱动了神秘的 He II 发射体 Hebe:第一代恒星还是黑洞?

Junehyoung Jeon, Tae Bong Jeong, Saiyang Zhang, Volker Bromm

AI总结 通过JWST光谱确认Hebe的强He II发射,对比Pop III星团形成模拟和SMBH模型,发现Pop III大质量星团(~10^5 M⊙)是最可能的电离源,支持其作为原初天体的解释。

Comments 10 pages, 4 figures. Accepted for publication in ApJ

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AI中文摘要

詹姆斯·韦伯太空望远镜(JWST)近期的高分辨率光谱证实了在GN-z11附近存在一个强He II λ1640发射团块,其金属丰度仅有上限。为了解释这个被称为Hebe的源的特殊性质,人们提出了一个无金属的第三族(Pop III)星团。较不可能产生硬紫外电离辐射的源可能是Hebe内部嵌入的吸积超大质量黑洞(SMBH)。我们在此进一步约束可能驱动Hebe中观测到的发射线的因素。通过与Pop III星团形成的宇宙学模拟比较,我们评估了在Hebe位置可能形成的最大Pop III恒星质量,发现恒星质量约为几×10^5 M⊙,与观测推断一致。通过对吸积SMBH产生的连续谱能谱分布建模,我们推导了He II和H I电离率以及由此产生的复合线光度,为联合观测提供了不太自然的拟合。因此,我们确认了Hebe作为一个引人注目的原初天体的解释,其最可能的能源是由一个巨大的Pop III星团提供的,这处于标准第一代恒星形成模型允许的极限。

英文摘要

Recent high-resolution spectroscopy with the James Webb Space Telescope (JWST) has confirmed the presence of a strong He II $\lambda1640$ emitting clump in the vicinity of GN-z11, with only upper limits on its metallicity. To explain the peculiar properties of this source, now termed Hebe, a cluster of metal-free, Population III (Pop III) stars has been invoked. A less likely source for the hard UV ionizing radiation could be an accreting supermassive black hole (SMBH) embedded inside Hebe. We here provide further constraints on what could power the observed emission lines in Hebe. Comparing with cosmological simulations of Pop III star cluster formation, we assess the maximum Pop III stellar mass that could plausibly form at the location of Hebe, finding stellar masses of a few $10^5\,M_{\odot}$, consistent with those inferred from the observations. Modeling the continuum spectral energy distribution arising from an accreting SMBH, we derive He II and H I ionizing rates and the resulting recombination line luminosities, providing a less natural fit for the combined observations. We thus confirm the interpretation of Hebe as a remarkable, primordial object, with the most plausible power source provided by a massive cluster of Pop III stars, at the limit of what is allowed within the standard model of first star formation.

2604.18812 2026-06-11 astro-ph.IM astro-ph.GA 版本更新

SAGUI: SED-based Segmentation of Multi-band Galaxy Images -- Application to JADES in GOODS-South

SAGUI: 基于SED的多波段星系图像分割——在GOODS-South JADES巡天中的应用

Rafael S. de Souza, Andressa Wille, Shravya Shenoy, Aarya A. Patil, Alberto Krone-Martins, Ana L. Chies-Santos, Celine Boehm, Reinaldo R. Rosa, Thallis Pessi, Emille E. O. Ishida, Kristen C. Dage, Lilianne Nakazono, Phelipe Darc, Rupesh Durgesh

AI总结 提出SAGUI框架,结合星基分解与光谱相似性分析,实现多波段星系图像像素级分割,有效识别致密结构、低面亮度成分及复杂形态,在JADES巡天11个星系中验证。

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AI中文摘要

我们提出SAGUI,一个用于空间分辨星系多波段成像数据分析的模块化框架,并与积分场光谱(IFS)协同。基于capivara为IFS数据引入的光谱-空间范式,SAGUI将该方法扩展到成像数据集,实现跨多个波段的空间和光谱信息的连贯像素级处理。该方法遵循两阶段策略:首先使用星基分解来识别和掩蔽跨多个尺度的空间结构,同时抑制噪声;然后进行光谱相似性分析,将图像划分为保持光谱一致性的相干像素组。除了紧凑和高对比度结构外,该框架还包含基于copula变换的专用统计处理,以识别和恢复微弱、弥散的低面亮度成分。我们在各种星系形态上演示了该方法,突出了其表征复杂空间结构(包括团块、棒、相互作用系统和低面亮度特征)的能力。作为案例研究,我们将其应用于GOODS-South场中詹姆斯·韦伯太空望远镜高级深河外星系巡天的11个形态多样的星系。SAGUI在MIT许可下发布,并可在以下网址获取:此https URL。

英文摘要

We present sagui, a modular framework for the analysis of multi-band imaging data in spatially resolved galaxies, with synergies to integral-field spectroscopy (IFS). Building on the spectro-spatial paradigm introduced by capivara for IFS data, sagui extends this approach to imaging datasets, enabling a coherent, pixel-level treatment of spatial and spectral information across multiple bands. The method follows a two-stage strategy: a starlet-based decomposition is first used to identify and mask spatial structures across multiple scales while suppressing noise, and a spectral-similarity analysis then partitions the image into coherent pixel groups that preserve spectral consistency. In addition to compact and high-contrast structures, the framework incorporates a dedicated statistical treatment, based on a copula transform, to identify and recover faint, diffuse low-surface-brightness components. We demonstrate the method across a diverse range of galaxy morphologies, highlighting its ability to characterize complex spatial structures, including clumps, bars, interacting systems, and low-surface-brightness features. As a case study, we apply it to eleven morphologically diverse galaxies from the James Webb Space Telescope Advanced Deep Extragalactic Survey in the GOODS--South field. sagui is released under an MIT license and is available at https://rafaelsdesouza.github.io/sagui/.

2510.18058 2026-06-11 cs.NI cs.DC 版本更新

A New Broadcast Model for Several Network Topologies

一种适用于多种网络拓扑的新型广播模型

Hongbo Lu, Junsung Hwang, Bernard Tenreiro, Nabila Jaman Tripti, Darren Hamilton, Yuefan Deng

AI总结 提出基于平衡饱和的广播(BBS)算法,通过树形流水线优化大规模消息广播的通信效率,在Mesh、Butterfly、Dragonfly和Fat-Tree拓扑上均优于现有算法。

Comments 30 pages, 7 figures

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AI中文摘要

我们引入了基于平衡饱和的广播(BBS),这是一类通用的基于树的流水线广播算法,旨在优化不同网络拓扑下的通信效率,特别关注大消息尺寸。通过解决广播中的两个基本理论挑战——生成树构建和通信任务调度,BBS提供了一个统一且灵活的框架,能够在各种网络约束下有效运行。该算法在最大化聚合吞吐量的同时,处理拓扑约束、同步开销、带宽限制和竞争。在标准假设(包括全双工和单端口通信)下,使用SimGrid在Mesh、Butterfly、Dragonfly和Fat-Tree拓扑上评估了多种算法。结果表明,BBS在多种拓扑和消息尺寸下始终优于通用和拓扑感知的广播算法,成为大规模系统中稳健且高性能的解决方案。

英文摘要

We introduce Broadcast by Balanced Saturation (BBS), a general class of tree-based pipelined broadcast algorithms that optimizes communication efficiency across diverse network topologies, with a particular emphasis on large message sizes. By addressing spanning tree construction and communication task scheduling, two fundamental theoretical challenges in broadcasting, BBS offers a unified and flexible framework that operates effectively under varied network constraints. The algorithm maximizes aggregated throughput while simultaneously addressing topology constraints, synchronization overhead, bandwidth limitations and contention. Using SimGrid under standard assumptions, including full-duplex and one-port communication, various algorithms were evaluated on Mesh, Butterfly, Dragonfly, and Fat-Tree topologies. Results demonstrate that BBS consistently outperforms both general-purpose and topology-aware broadcast algorithms across a wide range of topologies and message sizes, establishing it as a robust and high-performance solution for large-scale systems.

2604.16154 2026-06-11 astro-ph.CO gr-qc hep-th 版本更新

Probing Primordial Black Holes with upcoming Radio Telescopes: a case study for LOFAR2.0, FAST Core Array and BINGO

用即将到来的射电望远镜探测原初黑洞:LOFAR2.0、FAST Core Array和BINGO的案例研究

Joao R. L. Santos, Guillem Domènech, Amilcar R. Queiroz

AI总结 研究利用LOFAR2.0、FAST Core Array和BINGO三个射电望远镜对透镜化快速射电暴的探测能力,约束原初黑洞作为暗物质组分的比例,并给出质量相关的上限。

Comments 19 pages, 6 figures, to appear in JCAP

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AI中文摘要

快速射电暴(FRB)是射电天文学中观测到的最引人注目的现象之一。迄今为止,已有约130个FRB信号被不同巡天确认和表征,而CHIME望远镜最近报告了一个包含4539个暴发的新目录。因此,这些数字预计在未来几年还会增加。透镜化FRB事件的探测(或缺失)可用于探测原初黑洞(PBH)作为暗物质的一部分。我们研究了三个即将到来的射电望远镜——LOFAR2.0、FAST Core Array和BINGO——测试PBH情景的潜力。我们预测,对于PBH质量$M_{\rm PBH}>1\,{M_{\odot}}$,LOFAR2.0将把$f_{\mathrm{PBH}}$约束在$<0.16$;而FAST Core Array和BINGO将分别对$M_{\rm PBH}>10\,{M_{\odot}}$和$M_{\rm PBH}>10^{-1}\,{M_{\odot}}$限制$f_{\mathrm{PBH}}<0.39$。尽管存在更严格的约束,FRB透镜化为宇宙中的PBH提供了一个独立且互补的探测手段,这一手段将在未来得到改进。

英文摘要

Fast Radio Bursts (FRBs) are among the most intriguing phenomena observed in radio astronomy. So far, about 130 FRB signals have been confirmed and characterized by different surveys, and the CHIME telescope has recently reported a new catalog of 4539 bursts. Therefore, these numbers are expected to increase in the coming years. The detection, or lack thereof, of lensed FRB events can be used to probe Primordial Black Holes (PBHs) as a fraction of dark matter. We investigate the potential of three upcoming radio telescopes, LOFAR2.0, FAST Core Array, and BINGO, to test the PBH scenario. We forecast that LOFAR2.0 will constrain $f_{\mathrm{PBH}} < 0.16$ for PBH masses $M_{\rm PBH}>1\,{M_{\odot}}$, while FAST Core Array and BINGO will restrict $f_{\mathrm{PBH}} < 0.39$ for $M_{\rm PBH}>10\,{M_{\odot}}$ and $M_{\rm PBH}>10^{-1}\,{M_{\odot}}$, respectively. Despite the existence of stricter constraints, FRB lensing offers an independent and complementary probe of PBHs in the Universe, which will improve in the future.

2604.15984 2026-06-11 math.AT math.GT 版本更新

Rigidity of self-maps of $V_{n,2}$ and manifolds tangentially homotopy equivalent to $V_{n,2} \times S^k$

$V_{n,2}$ 的自映射以及与 $V_{n,2} \times S^k$ 切同伦等价的流形的刚性

Sagnik Biswas

AI总结 研究Stiefel流形V_{n,2}的自映射刚性与V_{n,2}×S^k切同伦等价流形的分类,通过法不变性寻找显式逆元,在特定情形下完成分类并揭示与怪球面的联系。

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AI中文摘要

我们研究关于 Stiefel 流形 $V_{n,2}$ 及其与球面乘积的两个问题。首先,我们解决一个刚性问题:对于大多数 $n$,我们确定所有同伦于几乎微分同胚的 $V_{n,2}$ 的自映射。其次,我们分类与 $V_{n,2} \times S^k$ 切同伦等价的闭光滑流形,其中 $k = 3, 5$ 或 $7 \leq k, k \neq 2^i - 2$ 且 $\operatorname{Dim}(V_{n,2} \times S^k) \neq 2^i - 2$,分类上至几乎微分同胚。我们的方法是通过特定切同伦等价的法不变性在结构集中寻找显式逆元。在有利情形——特别是 $V_{12,2} \times S^3$, $V_{16,2} \times S^3$, $V_{10,2} \times S^5$——分类是完整的:每个这样的流形都几乎微分同胚于 $V_{n,2} \mathbin{\\#} \Sigma \times S^k$,其中 $\Sigma$ 是某个怪球面。在一般情况下,我们为 $\operatorname{Im}(\eta)$ 的一个大子群识别逆元,并为剩余部分提供合理方向。

英文摘要

We study two problems concerning the Stiefel manifolds $V_{n,2}$ and their products with spheres. First, we address a rigidity problem: we determine, for most values of~$n$, all self-maps of $V_{n,2}$ that are homotopic to an almost diffeomorphism. Second, we classify smooth closed manifolds tangentially homotopy equivalent to $V_{n,2} \times S^k$ up to almost diffeomorphism, for $k = 3, 5$ or $7 \leq k, k \neq 2^i - 2 \ \text{and} \ Dim(V_{n,2} \times S^k) \neq 2^i - 2$. Our method is to find explicit inverses in the structure set via normal invariants of specific tangential homotopy equivalences. In favourable cases -- notably $V_{12,2} \times S^3$, $V_{16,2} \times S^3$, $V_{10,2} \times S^5$ -- the classification is complete: every such manifold is almost diffeomorphic to $V_{n,2} \mathbin{\#} Σ\times S^k$ for some exotic sphere $Σ$. In the general case, we identify inverses for a large subgroup of $\operatorname{Im}(η)$ and provide a reasonable direction for the remainder.

2604.15150 2026-06-11 cs.DL 版本更新

A Semantic Geometry for Uncovering Paradigm Dynamics via Scientific Publications

一种通过科学出版物揭示范式动态的语义几何

Jinchang Liu, Qingshan Zhou, Hongkan Chen, Yi Bu

AI总结 提出基于R-P-C(参考文献、焦点出版物、引文)框架的语义几何,通过量化出版物的知识基础与扩散的语义相似性和距离,识别巩固型、探索型和平衡型三类出版物,揭示范式动态。

Comments 40 pages,17figures

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AI中文摘要

科学进步不仅通过积累已发现的模式,还通过改变新问题和解决方案的表达方式。虽然结构指标追踪学术关注,但它们只是意义重组的间接代理。我们提出一种基于R-P-C(参考文献、焦点出版物和引文)框架的语义几何,用于量化出版物相对于其知识基础和扩散的定位。该几何识别三种出版物类型:巩固型、探索型和平衡型。我们的结果表明,出版物的知识基础与扩散之间的语义相似性和距离构成了颠覆的语义基础,而新颖性(非典型参考组合)作为触发语义断裂的前驱扰动。这与团队规模相关,小团队保持更高的探索性偏离潜力,而大合作则系统性地与范式巩固一致。关键的是,该几何解释了为何引文轨迹不同:巩固型研究通过降低理解成本获得快速认可,而探索型工作面临高范式转换成本,导致更慢、更具选择性的扩散。总体而言,这个R-P-C框架为监测科学范式动态提供了稳健的工具。

英文摘要

Science advances not only by accumulating discovered patterns but by changing how new problems and solutions are expressed. While structural indicators track scholarly attention, they offer only an indirect proxy for the reorganization of meaning. We propose a semantic geometry based on the R-P-C (references, focal publication, and citing publications) framework to quantify how a publication positions itself relative to its knowledge base and diffusion. This geometry identifies three publication types: consolidating, exploratory and balanced. Our results show that the semantic similarity and distance between a publication's knowledge base and diffusion serve as a semantic foundation for disruption, with novelty (atypical reference combinations) acting as an antecedent disturbance that triggers a semantic rupture. This is related to team size, where small teams preserve a higher potential for exploratory departures while large collaborations systematically align with paradigmatic consolidation. Crucially, this geometry explains why citation trajectories differ; consolidating research earns rapid recognition by lowering comprehension costs, while exploratory work faces high paradigm conversion costs that result in slower, more selective diffusion. Collectively, this R-P-C framework provides a robust instrument for monitoring the dynamics of scientific paradigms.

2604.14921 2026-06-11 quant-ph physics.comp-ph 版本更新

Split-Evolution Quantum Phase Estimation for Particle-Conserving Hamiltonians

粒子数守恒哈密顿量的分裂演化量子相位估计

Megan Cerys Rowe, Carlo A. Gaggioli, Ludmila Szulakowska, David Muñoz Ramo, David Zsolt Manrique

AI总结 提出分裂演化量子相位估计(SE-QPE),通过CSWAP干涉替代受控时间演化,降低粒子数守恒哈密顿量的量子资源消耗,在Quantinuum H2上演示并分析资源,实现约33% CX计数和25% T门减少。

Comments v2: Extended the hardware demonstration from 6 to 8 phase bits, expanded the FeMoco resource-estimation appendix and compilation details, updated absolute gate count scale, and minor text corrections

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AI中文摘要

我们展示了在Quantinuum System Model H2量子计算机上分裂演化量子相位估计(SE-QPE)的硬件演示和资源分析。SE-QPE是对粒子数守恒哈密顿量的标准QPE的改进,其中受控时间演化被基于CSWAP的目标寄存器和参考寄存器之间的干涉所替代。对于具有共享本征基的时间演化分解,SE-QPE保留了标准QPE的相位寄存器结果分布,并且与计算-非计算替换不同,它仍然与非精确本征态兼容。该替换消除了受控模拟的开销,并允许在两个寄存器上并行演化,从而减少了每个相位反冲块的深度。对Trotterized双因子分解化学哈密顿量的资源分析表明,在更高的相位幂次下,该替换变得越来越有利,并且结合QPE和SE-QPE实现可能是一个有用的选项。在一系列FeMoco活性空间上,SE-QPE减少了时间演化资源,CX计数渐近减少约33%,$T$门计数减少约25%,CX层的渐近深度比为$3/N$。在Quantinuum H2-2上,一个四量子比特模型乙烯演示,使用显式逆QFT和重复的相位反冲步骤(最多8个相位比特),产生了不同的能量,并显示了辅助寄存器提供了有用的错误检测滤波器。

英文摘要

We present a hardware demonstration and resource analysis of split-evolution quantum phase estimation (SE-QPE) on a Quantinuum System Model H2 quantum computer. SE-QPE is a modification to canonical QPE for particle-conserving Hamiltonians in which controlled time evolution is replaced by CSWAP-based interference between a target register and a reference register. For factorizations of time evolution with a shared eigenbasis, SE-QPE preserves the phase-register outcome distribution of canonical QPE and, unlike with compute--uncompute substitutions, it remains compatible with non-exact eigenstates. The substitution removes controlled-simulation overhead and enables parallel evolution on two registers, reducing the depth of each phase-kickback block. Resource analysis for Trotterized double-factorized chemistry Hamiltonians shows that the substitution becomes increasingly favorable at higher phase powers and combining QPE and SE-QPE implementations can be a useful option. Over a range of FeMoco active spaces, SE-QPE reduces time evolution resources, with asymptotic reductions of about 33% in CX count, 25% in $T$ count, and an asymptotic depth ratio of $3/N$ for CX layers. On Quantinuum H2-2, a four-qubit model ethylene demonstration with explicit inverse QFT and repeated phase-kickback steps up to 8 phase bits yields distinct energies and shows the auxiliary registers provide useful error detection filters.

2604.14671 2026-06-11 math.CO cs.IT math.IT 版本更新

On the independence number of de Bruijn graphs

de Bruijn 图的独立数

Pietro Majer, Matteo Novaga

AI总结 本文推导了 de Bruijn 图独立数的渐近公式,并通过变分问题确定常数,对 k=4 给出上下界,对奇素数 k 和 q=2 情形通过轨道相位约化得到精确公式。

Comments 34 pages

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AI中文摘要

我们推导了渐近公式 $\alpha(k,q)=\lambda_{k-1}q^k+o(q^k)$,其中 $\alpha(k,q)$ 是 de Bruijn 图 $B(k,q)$ 的独立数,$\lambda_{k-1}$ 是来自单位 $(k-1)$ 维立方体上一个变分问题的常数。当 $k=4$ 时,我们给出界 $91/240\le \lambda_3\le 11/28$。对于奇素数 $k$,我们通过旋转轨道上的相位约化分析二进制情形 $q=2$。对于 $k=11,13,17$,这产生了最优构造的紧致轨道标记证书。结合 Lichiardopol 的提升定理,这些证书给出了对所有 $q\ge2$ 的 $\alpha(11,q)$、$\alpha(13,q)$ 和 $\alpha(17,q)$ 的精确公式,扩展了已知情形 $k=3,5,7$。

英文摘要

We derive the asymptotic formula $α(k,q)=λ_{k-1}q^k+o(q^k)$, where $α(k,q)$ is the independence number of the de Bruijn graph $B(k,q)$, and $λ_{k-1}$ is a constant arising from a variational problem on the unit $(k-1)$-dimensional cube. When $k=4$, we show the bounds $91/240\le λ_3\le 11/28$. For odd prime $k$, we analyse the binary case $q=2$ via a phase reduction on rotation orbits. For $k=11,13,17$ this yields compact orbit-marker certificates for optimal constructions. Combined with a lifting theorem by Lichiardopol, these certificates give exact formulas for $α(11,q)$, $α(13,q)$, and $α(17,q)$ for all $q\ge2$, extending the known cases $k=3,5,7$.

2604.14273 2026-06-11 astro-ph.GA 版本更新

Cold vs. Hot Gas Accretion and Angular Momentum in FIRE Simulations: From Halo to Galaxy Scales

FIRE模拟中的冷气体吸积与热气体吸积及角动量:从晕到星系尺度

Imran Sultan, Claude-André Faucher-Giguère, Jonathan Stern, Guochao Sun

AI总结 利用高分辨率FIRE宇宙学模拟,系统研究星系周介质中的气体吸积和角动量,发现内CGM的维里化与入流气体温度相关,冷入流主导前维里化晕,热入流主导维里化晕,且冷入流比暗物质和热气体具有更高比角动量,但爆裂星系中冷入流未圆化,稳态星系中热入流圆化冷却形成盘状恒星。

Comments 26 pages, 20 figures. Accepted by MNRAS

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AI中文摘要

我们利用高分辨率FIRE宇宙学模拟对星系周介质(CGM)中的气体吸积和角动量进行了系统研究。我们的分析涵盖了关键的$\sim 10^{12}\ \mathrm{M}_{\odot}$尺度晕,在该尺度上已识别出多个转变,包括内CGM的维里化、从爆裂到稳态恒星形成的转变以及薄盘的出现。我们发现入流气体的温度与内CGM的维里化相关。在前维里化晕中,CGM入流几乎完全是冷的($T < 10^5$ K),而在维里化晕中,热入流($T > 10^5$ K)占主导。当热入流占主导时,冷却通常与星系半径处的圆化同时发生。即使在冷流可能共存的高红移处,大质量星系上的热入流主导地位仍然持续。与先前研究一致,冷入流比暗物质和热气体具有更高的比角动量。然而,在爆裂的低质量星系中,冷入流在恒星形成前未圆化,而在稳态的大质量星系中,热入流圆化、冷却并形成具有盘状运动学的恒星。我们还发现,在爆裂星系中,吸积的气体通常在星系中停留不到$\sim 5$个星系自由落体时间后形成恒星,而在稳态星系中,气体在形成恒星前可停留长达$\sim 25$个自由落体时间。这突显了由冷吸积供给的爆裂星系与由热吸积供给的稳态平衡盘之间恒星形成的关键差异。

英文摘要

We present a systematic study of gas accretion and angular momentum in the circumgalactic medium (CGM) using high-resolution FIRE cosmological simulations. Our analysis includes halos spanning the critical $\sim 10^{12}\ \mathrm{M}_{\odot}$ scale where several transitions have been identified, including inner CGM virialization, the transition from bursty to steady star formation, and the emergence of thin disks. We find that the temperature of inflowing gas is correlated with the virialization of the inner CGM. CGM inflows are almost entirely cold ($T < 10^5$ K) in pre-virialized halos, while hot inflows ($T > 10^5$ K) dominate in virialized halos. When hot inflows dominate, cooling generally occurs simultaneously with circularization at galaxy radii. The dominance of hot inflows onto massive galaxies persists even at high redshift, where cold streams may coexist. Consistent with previous studies, cold inflows have higher specific angular momentum than dark matter and hot gas. However, in bursty, low-mass galaxies, cold inflows do not circularize prior to star formation, while in steady, massive galaxies, hot inflows circularize, cool, and form stars with disk-like kinematics. We additionally find that in bursty galaxies, accreted gas typically forms stars after residing in the galaxy for less than $\sim 5$ galaxy free-fall times, while in steady galaxies, gas can persist for up to $\sim 25$ free-fall times before forming stars. This highlights a key difference between star formation in bursty galaxies fed by cold accretion and steady equilibrium disks fed by hot accretion.

2512.19912 2026-06-11 cs.CE math.OC 版本更新

Solving strategies for data-driven one-dimensional elasticity exhibiting nonlinear strains

数据驱动下具有非线性应变的弹性问题的求解策略

Thi-Hoa Nguyen, Viljar H. Gjerde, Bruno A. Roccia, Cristian G. Gebhardt

AI总结 提出一种结合贪婪优化和交替方向法的数据驱动求解策略,用于非线性应变弹性结构,能更好逼近全局最优解,但计算成本更高。

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AI中文摘要

在这项工作中,我们扩展并推广了最初在[1]中引入的求解策略,该策略基于贪婪优化算法和用于多载荷步非线性系统的交替方向法(ADM)。具体而言,我们将贪婪优化算法与基于ADM的直接数据驱动求解器相结合,该求解器首次在[2]中引入,并在[3]中与牛顿-拉夫森方法结合用于非线性弹性。我们通过一维和二维的杆和桁架结构(具有非线性应变度量和不同本构数据集)进行数值示例,表明我们的求解策略通常能更好地逼近全局最优解。然而,这是以更高的计算成本为代价的,该成本随“贪婪”搜索次数而缩放。使用这种求解策略,我们重现了在工业测试设施中为系泊绳制造商进行的尼龙绳循环测试的第一个循环。我们还通过桁架结构数值示例表明,在非对称数据分布和噪声数据的情况下,我们的求解策略通常能提高精度和鲁棒性。

英文摘要

In this work, we extend and generalize our solving strategy, first introduced in [1], based on a greedy optimization algorithm and the alternating direction method (ADM) for nonlinear systems computed with multiple load steps. In particular, we combine the greedy optimization algorithm with the direct data-driven solver based on ADM which is firstly introduced in [2] and combined with the Newton-Raphson method for nonlinear elasticity in [3]. We numerically illustrate via one- and two-dimensional bar and truss structures exhibiting nonlinear strain measures and different constitutive datasets that our solving strategy generally achieves a better approximation of the globally optimal solution. This, however, comes at the expense of higher computational cost which is scaled by the number of "greedy" searches. Using this solving strategy, we reproduce the first cycle of the cyclic testing for a nylon rope that was performed at industrial testing facilities for mooring lines manufacturers. We also numerically illustrate for a truss structure that our solving strategy generally improves the accuracy and robustness in cases of an unsymmetrical data distribution and noisy data.

2604.13821 2026-06-11 cond-mat.mtrl-sci nlin.CG 版本更新

Complex surface patterning in homo- and heteroepitaxial contexts: (simultaneous) step bunching and step meandering

同质与异质外延背景下的复杂表面图案化:(同时)台阶聚束与台阶蜿蜒

Vassil Ivanov, Vesselin Tonchev, Marta A. Chabowska, Hristina Popova, Magdalena A. Załuska-Kotur

AI总结 通过对比介观连续模型与原子尺度VicCA模型,证明(2+1)D复杂表面不稳定性是基本生长现象,并揭示台阶聚束与台阶蜿蜒可共存。

Comments 13 pages, 8 figures

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AI中文摘要

我们面对一个典型的异质外延背景下的介观连续模型,与一个作为同质外延对应物的原子尺度Vicinal元胞自动机(VicCA)进行对比,以证明在(2+1)D中,复杂表面不稳定性是基本的生长现象,而非特定于背景的伪影。我们的方法是首先构建一个Ginzburg-Landau型模型,旨在将先前的(1+1)D Tersoff型模型扩展到(2+1)D。我们用一个离散方法——VicCA来补充连续方法,其中我们使用了一种新颖的扩散粒子势能景观版本——位于每个台阶边缘的双阱势。值得注意的是,该框架还再现了台阶聚束和台阶蜿蜒——这些在理论范式中通常被视为不相容,但在真实材料系统中共存。因此,我们在获得的形貌和形貌图层面建立了跨背景对应关系,此外,对控制参数提供了多尺度视角,弥合了介观尺度与原子尺度建模之间的差距。

英文摘要

We confront a meso-scale continuum model, archetypical for the heteroepitaxial context, with an atomistic Vicinal Cellular Automaton (VicCA), built as a homoepitaxial counterpart, to show that in (2+1)D complex surface instabilities are fundamental growth phenomena rather than context-specific artifacts. Our approach is to first construct a Ginzburg-Landau-type model, designed to extend the previously (1+1)D Tersoff-type models in (2+1)D. We complement the continuum approach with a discrete one - the VicCA, in which we use a novel version of the potential landscape for the diffusing particles - a double-well potential located at each step edge. Notably, this framework also reproduces step bunching and step meandering - which are typically treated as incompatible in the theoretical paradigm, but coexist in real material systems. Thus we establish a cross-context correspondence at the level of obtained morphologies and morphology diagrams and, additionally, a multiscale perspective on the governing parameters, bridging the gap between the mesoscale and atomistic modeling.

2512.11717 2026-06-11 hep-ph 版本更新

Renormalization of mixing angles and computation of the hadronic $W$ decay widths

混合角的重整化与强子$W$衰变宽度的计算

Simonas Draukšas

AI总结 提出一种无需混合矩阵抵消项的On-Shell方案变体,基于自能统一处理混合矩阵和Weinberg角的重整化,并计算标准模型中$W$玻色子1-loop强子衰变宽度。

Comments 32 pages; corrections and improvements, updated appendix

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AI中文摘要

我们为On-Shell方案的一种变体提供了实用规则,该变体完全不需要混合矩阵抵消项,即$\delta V=0$。该方案基于这样一个事实:总可以选择一个没有混合矩阵(角度)的基,因此相应的抵消项是多余的。重要的是,该规则是模型和过程无关的,并且完全用自能表述。作为例子,我们计算了标准模型中$W$玻色子的1-loop强子衰变宽度,采用了文献中发现的以及本文发现的夸克混合矩阵的不同重整化方案。为了完全一致,该方案的原理同时应用于夸克混合矩阵和Weinberg角。

英文摘要

We provide a practical prescription for a variant of the On-Shell scheme which does not require mixing matrix counterterms at all, i.e. $δV=0$. The scheme is based on the fact that one can always choose a basis in which there are no mixing matrices (angles) and, therefore, the corresponding counterterms are superfluous. Importantly, the prescription is model- and process-independent and is formulated entirely in terms of self-energies. As an example, we compute the 1-loop hadronic $W$-boson decay widths in the Standard Model with different renormalization schemes of the quark mixing matrix found in the literature and the one found in this paper. For full consistency, the principles of this scheme are employed both for the quark mixing matrix and for the Weinberg angle.

2604.11974 2026-06-11 astro-ph.GA 版本更新

Reconstructing chemical enrichment pathways in disc galaxies: A phylogenetic approach

重建盘状星系中的化学增丰路径:一种系统发育方法

Brian Tapia-Contreras, Patricia B. Tissera, Emanuel Sillero, Paula Jofré, Keaghan Yaxley, Xia Hua, Robert M. Yates, Álvaro Márquez S., Theosamuele Signor, Payel Das, Álvaro Rojas-Arriagada, Claudia Aguilera-Gómez, Francisco Jara-Ferreira, Robert A. Foley

AI总结 利用系统发育方法,基于高分辨率模拟盘状星系中不同区域的恒星化学丰度数据,重建恒星种群的化学演化历史,揭示了内环和外盘不同的增丰模式与结构特征。

Comments 12 pages, 11 figures, 3 appendices. Accepted for publication in A&A

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AI中文摘要

系统发育方法传统上用于生物学中追溯物种间的进化关系,现在正成为一种从化学信息重建星系演化过程的强大框架。我们应用星系系统发育学来研究模拟盘状星系不同区域恒星种群的化学演化,评估其揭示组装历史的能力。我们使用了一个高分辨率模拟,追踪了孤立盘状星系中不同恒星前身星导致的化学增丰。我们追踪气体粒子转化为恒星并继承其母体气体化学成分的过程。目标粒子被选择来存储模拟中考虑的每种化学元素的化学历史。分析了两个区域:一个受早期棒驱动内流影响的内环,以及一个由旋臂塑造的外环。我们为每个区域的恒星种群构建了系统发育树,并使用校正的Colless指数(生物学中用于衡量树平衡的标准指标)量化其结构。内环树显示出一个由快速SNII反馈增丰的老年恒星组成的紧凑分支,随后是SNIa和AGB贡献增加的层级序列。相比之下,外环呈现出更对称的毛虫状树,丰度梯度更平滑,与更持久的恒星形成和有效的局部混合一致。化学增丰速率证实了这些趋势,显示内环早期快速增丰,外盘则逐渐、空间扩展地增丰。结构指数在两个区域间差异显著,并且即使对于中等大小的恒星样本(NSSP = 100)也能稳健收敛。星系系统发育学提供了一种新颖且互补的工具来解码星系的化石记录。

英文摘要

Phylogenetic methods, traditionally used in biology to trace the evolutionary relationships among species, are emerging as a powerful framework to reconstruct evolutionary processes in galaxies from chemical information. We apply galactic phylogenetics to study the chemical evolution of stellar populations in distinct regions of a simulated disc galaxy, assessing its capability to unveil assembly histories. We used a high-resolution simulation that follows the chemical enrichment of an isolated disc galaxy, by different stellar progenitors. We track gas particles as they turn into stars and inherit their parent gas chemical composition. Target particles are selected to store the chemical history of each chemical element considered in the simulation. Two regions were analysed: an inner ring, influenced by early bar-driven inflows, and an outer ring, shaped by spiral arms. We built phylogenetic trees for stellar populations in each region and quantified their structure using the Corrected Colless index, a standard metric of tree balance used in biology. The inner ring tree reveals a compact clade of old stars enriched by rapid SNII feedback, followed by a hierarchical sequence with increasing SNIa and AGB contributions. In contrast, the outer ring exhibits more symmetric, caterpillar-like trees with smoother abundance gradients, consistent with more prolonged star formation and efficient local mixing. Chemical enrichment rates corroborate these trends, showing fast early enrichment in the inner ring and gradual, spatially extended enrichment in the outer disc. The structural indices differ significantly between the two regions and converge robustly even for modest stellar samples (NSSP = 100). Galactic phylogenetics provides a novel and complementary tool to decode the fossil record of galaxies.

2604.11574 2026-06-11 hep-ex hep-ph nucl-ex 版本更新

SemiCharmTag: a tool for Semileptonic Charm tagging

SemiCharmTag:半轻粲标记工具

Carolina Arata, Imanol Corredoira, Alisha Lightbody, Michael Winn

AI总结 提出基于强子径迹标记次级顶点的方法,用于选择或拒绝粲半轻衰变中的轻子,在LHCb的Drell-Yan测量中实现背景抑制因子约4,效率81%。

Comments 21 pages (figures and references included), 10 figures

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AI中文摘要

介绍了一种基于强子径迹标记次级顶点来选择或拒绝来自粲半轻衰变轻子的方法。该方法针对LHCb中双缪子Drell-Yan测量开发,使用在$\sqrt{s}=13.6$ TeV质子-质子碰撞中的全模拟。我们关注不变质量范围在2.9到5 GeV/$c^2$之间,单缪子横向动量大于1 GeV/$c$。详细描述了一种新颖的背景抑制策略,在效率为81%时实现了信号与背景比提高约4倍,同时除了在接收边缘外,Drell-Yan运动学分布基本无偏。此外,还提出了第二种方法,用于构建来自粲衰变的单缪子的无偏背景纯净样本,在Drell-Yan效率为1.1%时达到21.4%的粲效率。

英文摘要

A method for selecting and/or rejecting leptons from charm semileptonic decays based on the tagging of the secondary vertex using a hadron track is introduced. The method is developed for dimuon Drell-Yan measurements in LHCb using full simulations in proton-proton collisions at $\sqrt{s}=13.6$ TeV. We focus on the invariant mass range between 2.9 and 5 GeV/$c^2$ with single muon transverse momentum larger than 1 GeV/$c$. A novel strategy is detailed for background rejection, achieving an improvement of the signal over background of a factor $\sim 4$ at an efficiency of 81% while maintaining the Drell-Yan kinematic distributions largely unbiased except at the acceptance edges. Moreover, a second approach is presented for the construction of unbiased background-pure samples of single muons from charm decays, achieving a charm efficiency of 21.4% at a Drell-Yan efficiency of 1.1%.

2604.11454 2026-06-11 cs.DB cs.PL 版本更新

Foundations of the GraphAlg Language

GraphAlg语言基础

Daan de Graaf, Robert Brijder, Nikolay Yakovets

AI总结 本文展示图算法领域特定语言GraphAlg如何建立在矩阵操作形式语言MATLANG之上,通过扩展和语法糖实现,并证明任何GraphAlg程序可在支持同时归纳的for-MATLANG扩展中模拟。

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AI中文摘要

用于图算法的领域特定语言GraphAlg使得用户能够在图数据库中定义算法。在这项工作中,我们展示了GraphAlg是如何建立在用于矩阵操作的形式化语言MATLANG之上的。从MATLANG出发,我们描述了为推导出GraphAlg所需的MATLANG扩展和语法糖。此外,我们证明了任何GraphAlg程序都可以在支持同时归纳的for-MATLANG扩展中被模拟。

英文摘要

The GraphAlg domain-specific language for graph algorithms enables user-defined algorithms in graph databases. In this work we show how GraphAlg is built on top of the formal MATLANG language for matrix manipulation. Starting from MATLANG, we describe the extensions to MATLANG and the syntactic sugar needed to derive GraphAlg. Furthermore, we prove that any GraphAlg program can be simulated in an extension of for-MATLANG that supports simultaneous induction.

2604.11232 2026-06-11 hep-ph 版本更新

Machine learning study on single production of a singlet vectorlike lepton at the Large Hadron Collider

大型强子对撞机上单态矢量轻子单产生的机器学习研究

Yiheng Cui, Shiyu Wang, Zhao-Huan Yu, Hong-Hao Zhang

AI总结 利用XGBoost算法研究大型强子对撞机上与τ轻子混合的单态矢量轻子的单产生,通过三轻子和四轻子通道,在14 TeV和3000 fb^{-1}条件下,排除质量上限分别达500和405 GeV。

Comments 24 pages, 10 figures; revisions to match the published version

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Journal ref
Phys. Rev. D 113, 115025 (2026)
AI中文摘要

矢量轻子是超越标准模型的新物理中的非手性、无色费米子,出现在许多理论扩展中。我们研究了在大型强子对撞机上与τ轻子混合的单态矢量轻子的单产生的探测前景。相应的末态被分类为三轻子和四轻子搜索通道。采用机器学习算法XGBoost来增强信号与背景的区分。我们的分析表明,在$\sqrt{s} = 14~\mathrm{TeV}$、积分亮度为$3000~\mathrm{fb}^{-1}$且假设系统误差可忽略的条件下,三轻子和四轻子通道中预期的$2\sigma$排除极限在电弱斜参数约束允许的参数区域内分别可达矢量轻子质量$500$和$405~\mathrm{GeV}$。这些发现表明,机器学习技术可以显著提高对撞机搜索矢量轻子的灵敏度。

英文摘要

Vectorlike leptons are nonchiral, colorless fermions from new physics beyond the Standard Model, appearing in many theoretical extensions. We investigate the prospect for detecting the single production of a singlet vectorlike lepton that mixes with the $τ$ lepton at the Large Hadron Collider. The corresponding final states are classified as the three- and four-lepton search channels. The machine learning algorithm XGBoost is employed to enhance signal-background discrimination. Our analysis indicates that, at $\sqrt{s} = 14~\mathrm{TeV}$ with an integrated luminosity of $3000~\mathrm{fb}^{-1}$ under the assumption of negligible systematic uncertainties, the expected $2σ$ exclusion limits in the three- and four-lepton channels can reach vectorlike lepton masses up to $500$ and $405~\mathrm{GeV}$ in the parameter region allowed by the electroweak oblique parameter constraint, respectively. These findings demonstrate that machine learning techniques can substantially improve the sensitivity of collider searches for vectorlike leptons.

2604.10639 2026-06-11 cs.NE cs.ET 版本更新

Visualising the Attractor Landscape of Neural Cellular Automata

神经细胞自动机的吸引子景观可视化

James Stovold, Mia-Katrin Kvalsund, Harald Michael Ludwig, Varun Sharma, Alexander Mordvintsev

AI总结 本文应用流形学习和拓扑数据分析技术,从宏观和微观层面揭示神经细胞自动机(NCA)的行为流形,以增强其可解释性。

Comments Accepted to ALIFE 2026

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AI中文摘要

随着神经细胞自动机(NCA)越来越多地应用于人工生命中的玩具模型之外,迫切需要理解它们的行为并建立适当的途径来解释它们所学到的东西。就其本质而言,训练NCA的好处与缺乏可解释性相平衡:我们可以设计涌现行为,但理解所学内容的能力有限。在本文中,我们应用多种技术来撬开NCA的黑箱,并对其所学内容有所了解。我们应用流形学习技术(主成分分析以及密集和稀疏自编码器)以及拓扑数据分析技术(持续同调)来捕获NCA的底层行为流形,取得了不同程度的成功。结果表明,当在宏观层面进行分析(即把整个NCA状态作为一个数据点)时,底层流形通常相当简单,可以很好地捕获和分析。当在微观层面进行分析(即把单个细胞的状态作为一个数据点)时,流形高度复杂,需要更复杂的技术才能理解它。

英文摘要

As Neural Cellular Automata (NCAs) are increasingly applied outside of the toy models in Artificial Life, there is a pressing need to understand how they behave and to build appropriate routes to interpret what they have learnt. By their very nature, the benefits of training NCAs are balanced with a lack of interpretability: we can engineer emergent behaviour, but have limited ability to understand what has been learnt. In this paper, we apply a variety of techniques to pry open the NCA black box and glean some understanding of what it has learnt to do. We apply techniques from manifold learning (principal components analysis and both dense and sparse autoencoders) along with techniques from topological data analysis (persistent homology) to capture the NCA's underlying behavioural manifold, with varying success. Results show that when analysis is performed at a macroscopic level (i.e. taking the entire NCA state as a single data point), the underlying manifold is often quite simple and can be captured and analysed quite well. When analysis is performed at a microscopic level (i.e. taking the state of individual cells as a single data point), the manifold is highly complex and more complicated techniques are required in order to make sense of it.

2604.10620 2026-06-11 nucl-th hep-ph nucl-ex 版本更新

Complementary Approach to Anisotropic Flows in Heavy-Ion Collisions

重离子碰撞中各向异性流的互补方法

E. Dlin, O. Teryaev

AI总结 提出无需事件平面重建的no-RP方法,通过固定测试角计数不对称性提取直接流和椭圆流,经PHSD模型验证,与真实反应平面结果高度相关。

Comments 5 pages, 6 figures. Minor changes

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AI中文摘要

我们引入了一种无反应平面(no-RP)方法,用于提取重离子碰撞中的直接流(\\(v_1\\))和椭圆流(\\(v_2\\)),该方法无需重建事件平面。%通过扫描固定测试角并使用简单的计数不对称性。该方法通过PHSD模型模拟的\\(\sqrt{s_{NN}} = 9.2\\) GeV下Au+Au碰撞(碰撞参数\\(b = 4-8\\) fm)在冻结时刻的模拟进行了验证。我们证明了每个谐波的两个不对称性贡献相等,即\\(\langle A_{\mathrm{ud}}^2\rangle \approx \langle A_{\mathrm{lr}}^2\rangle\\)和\\(\langle A_1^2\rangle \approx \langle A_2^2\rangle\\),因此单个不对称性测量足以获得良好的流估计。与使用真实反应平面的直接计算进行逐事件比较,得到\\(v_2\\)的Pearson相关系数为0.956,\\(v_1\\)为0.834,证实了no-RP方法能够很好地捕捉流涨落。

英文摘要

We introduce a no-reaction-plane (no-RP) method for extracting directed (\(v_1\)) and elliptic (\(v_2\)) flows in heavy-ion collisions, which eliminates the need for event-plane reconstruction. %by scanning over fixed test angles and using simple count asymmetries. The method is validated with PHSD model simulations of Au+Au collisions at \(\sqrt{s_{NN}} = 9.2\) GeV at freeze-out (for impact parameters \(b = 4-8\) fm). We demonstrate that the two asymmetries for each harmonic contribute equally, i.e., \(\langle A_{\mathrm{ud}}^2\rangle \approx \langle A_{\mathrm{lr}}^2\rangle\) and \(\langle A_1^2\rangle \approx \langle A_2^2\rangle\), so that a single asymmetry measurement suffices for a good flow estimate. Event-by-event comparisons with direct calculations using the true reaction plane yield Pearson correlation coefficients of 0.956 for \(v_2\) and 0.834 for \(v_1\), confirming that the no-RP method captures flow fluctuations well enough.

2604.10615 2026-06-11 math.OC 版本更新

Unified Communication Compression Beyond Global Error Bounds for Distributed Nonconvex Optimization

超越全局误差界的分布式非凸优化统一通信压缩

Haonan Wang, Minghui Liwang, Yiguang Hong, Karl H. Johansson, Xinlei Yi

AI总结 提出统一压缩算法处理局部和全局有界通信压缩器,在非凸设置下证明收敛性,并建立P-L条件下的线性收敛,局部有界类达到O(1/√T)速率,与中心化1-bit压缩器匹配。

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AI中文摘要

本文提出了一种用于分布式非凸优化的统一压缩算法,适用于局部有界和全局有界的通信压缩器,包括1-bit压缩器、饱和量化器以及具有相对和绝对压缩误差的全局有界压缩器,以及额外的任意有界噪声。我们在非凸设置下提供了严格的收敛性分析,并在Polyak-Lojasiewicz (P-L)条件下建立了线性收敛。值得注意的是,我们在分布式非凸设置下为局部有界类建立了$\mathcal{O}(1/\sqrt{T})$的收敛速率,与使用1-bit压缩器的中心化算法相匹配,其中$T$表示总迭代次数。此外,一轮初始未压缩通信进一步将速率提升至$\mathcal{O}(1/T^{2/3})$。对于P-L设置和全局有界类,我们恢复了最先进的收敛速率。

英文摘要

In this paper, we propose a unified compression algorithm for distributed nonconvex opitmization with both the locally- and globally-bounded communication compressors, including 1-bit compressors, saturating quantizers, and the globally-bounded compressors with both relative and absolute compression errors, as well as additional arbitrary bounded noise. We provide a rigorous convergence analysis in nonconvex settings and establish linear convergence under the Polyak-Lojasiewicz (P-L) condition. Notably, we establish an $\mathcal{O}(1/\sqrt{T})$ convergence rate for the locally-bounded class in the distributed nonconvex setting, matching that achieved by the centralized algorithms with 1-bit compressors, where $T$ denotes the total number of iterations. Moreover, one initial uncompressed communication round further yields an order-wise improvement to $\mathcal{O}(1/T^{2/3})$. For the P-L setting and the globally-bounded class, we recover state-of-the-art convergence rates.

2601.19093 2026-06-11 quant-ph 版本更新

Residual-Squeezing Mechanism of Mismatch in Inverse-Squeezing Kennedy Receivers

逆压缩Kennedy接收机中失配的残余压缩机制

Enhao Bai, Fengkai Sun, Tianyi Wu, Yang Ran, Zichao Zhou, Huankai Zhang, Jian Peng, Chen Dong, Laiyuan Tong, Zhenrong Zhang, Yaping Li

AI总结 研究逆压缩Kennedy接收机中压缩失配如何通过残余压缩机制导致误差,发现幅度失配产生能量无关误差基底,相位失配导致误差随能量增长,并识别出奇偶步效应。

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AI中文摘要

量子态的区分是量子信息处理的基础。逆压缩Kennedy(IS-Kennedy)接收机通过将发射端压缩转换为有效的相干态分离增益,可以在相同能量下超越相干态BPSK Helstrom基准,而不违反压缩态字母集的Helstrom界。本文研究压缩失配如何削弱这一机制。我们表明,不完美的逆压缩将理想归零输出转化为残余压缩态,从而改变检测前的光子数统计。这种残余压缩图像揭示了压缩幅度失配和压缩相位失配之间的强烈物理不对称性。幅度失配在高信号能量区域产生能量无关的误差基底,而相位失配产生随信号能量增长的残余压缩项。在小残余压缩区域,这导致主导误差贡献的多项式增长和SQL优势的快速消失。我们还在光子数分辨检测中识别出奇偶步效应:由于归零的残余压缩真空仅包含偶数光子数,增加探测器分辨率仅在有效饱和阈值跨越下一个偶数光子数时提高高能量鲁棒性。这些结果将相位锁定确定为IS-Kennedy型非高斯接收机在幺正压缩失配下的主要瓶颈,并为鲁棒压缩态量子接收机的设计提供了指导方针。

英文摘要

The discrimination of quantum states is fundamental to quantum information processing. Inverse-squeezing Kennedy (IS-Kennedy) receivers can outperform the coherent-state BPSK Helstrom benchmark at the same energy by converting transmitter-side squeezing into an effective coherent-state separation gain, without violating the Helstrom bound for the squeezed-state alphabet. This work investigates how squeezing mismatch degrades this mechanism. We show that imperfect inverse squeezing transforms the ideally nulled output into a residually squeezed state, thereby altering the photon-number statistics before detection. This residual-squeezing picture reveals a strong physical asymmetry between squeezing-magnitude and squeezing-phase mismatches. Magnitude mismatch produces an energy-independent error floor in the high-signal-energy regime, whereas phase mismatch generates a residual squeezing term that grows with signal energy. In the small-residual-squeezing regime, this leads to a polynomial growth of the leading error contribution and a rapid collapse of the SQL advantage. We also identify a parity-step effect in photon-number-resolving detection: because the nulled residual squeezed vacuum contains only even photon numbers, increasing detector resolution improves the high-energy robustness only when the effective saturation threshold crosses the next even photon number. These results identify phase locking as the dominant bottleneck for IS-Kennedy-type non-Gaussian receivers under unitary squeezing mismatch and provide design guidelines for robust squeezed-state quantum receivers.

2508.05032 2026-06-11 math.PR 版本更新

On the spatio-temporal increments of nonlinear parabolic SPDEs and the open KPZ equation

关于非线性抛物型随机偏微分方程的时空增量与开放KPZ方程

Jingwu Hu, Cheuk Yin Lee

AI总结 研究有界区间上非线性抛物型SPDE解的时空增量,确定了精确的局部和一致模连续性,并推广到开放KPZ方程。

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AI中文摘要

我们研究有界区间上具有Dirichlet、Neumann或Robin边界条件的非线性抛物型随机偏微分方程解的时空增量。我们确定了解的样本函数的精确局部和一致时空连续模。这些连续模结果暗示了时空振荡异常大的时空随机点的存在。我们还建立了时空增量的小球概率估计和Chung型重对数律。我们的方法将这些结果中的一部分推广到单位区间上具有非齐次Neumann边界条件的开放KPZ方程。我们的关键要素包括各种边界条件下线性随机热方程的新强局部非确定性结果,以及非线性方程解的时空增量线性化误差的详细估计。

英文摘要

We study spatio-temporal increments of the solutions to nonlinear parabolic SPDEs on a bounded interval with Dirichlet, Neumann, or Robin boundary conditions. We identify the exact local and uniform spatio-temporal moduli of continuity for the sample functions of the solutions. These moduli of continuity results imply the existence of random points in space-time at which spatio-temporal oscillations are exceptionally large. We also establish small-ball probability estimates and Chung-type laws of the iterated logarithm for spatio-temporal increments. Our method yields extension of some of these results to the open KPZ equation on the unit interval with inhomogeneous Neumann boundary conditions. Our key ingredients include new strong local non-determinism results for linear stochastic heat equation under various types of boundary conditions, and detailed estimates for the errors in linearization of spatio-temporal increments of the solution to the nonlinear equation.

2507.19258 2026-06-11 quant-ph 版本更新

Probing Quantum States over Spacetime Through Interferometry

通过干涉测量探测时空中的量子态

Seok Hyung Lie, Hyukjoon Kwon

AI总结 本文通过因果无关测量和干涉技术,统一了密度算符、时间量子态和过程矩阵形式,揭示了时间反演对称性下的时空关联,并展示了其在区分动力学中的应用。

Comments 5+14 pages; closer to journal submission, comments welcome

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AI中文摘要

建立一种在空间和时间上一致适用的量子态概念,可能是迈向相对论量子理论的关键一步。我们通过一种因果无关的测量方案,为时空任意区域上的多部分量子态赋予了操作意义,该测量方案可以独立于区域之间的因果关系一致地实现。我们证明,此类测量总是可以通过干涉测量(也称为散射电路技术)实现,其中传统的密度算符、最近发展的时间量子态(QSOT)和过程矩阵形式主义平滑地融合。该框架允许系统研究时间设定中的混合态,这对建模量子非马尔可夫性至关重要。基于此,我们证明两个不同的量子动力学系综可以由相同的QSOT表示,表明它们无法通过干涉测量区分。此外,我们的形式主义揭示了一种新的时空关联,源于时间反演对称性下的同步时间传播。我们证明,具有这种关联的量子系统可以用作参考系,以区分某些在时间反演对称性下无法区分的动力学。

英文摘要

Establishing a notion of the quantum state that applies consistently across space and time could be a crucial step toward formulating a relativistic quantum theory. We give an operational meaning to multipartite quantum states over arbitrary regions in spacetime through a causally agnostic measurement, a measurement scheme that can be consistently implemented independently of the causal relation between the regions. We prove that such measurements can always be implemented with interferometry, also known as the scattering circuit technique, wherein the conventional density operator, the recently developed quantum state over time (QSOT), and the process matrix formalisms smoothly merge. This framework allows for a systematic study of mixed states in the temporal setting, which turn out to be crucial for modeling quantum non-Markovianity. Based on this, we demonstrate that two different ensembles of quantum dynamics can be represented by the same QSOT, indicating that they cannot be distinguished through interferometry. Moreover, our formalism reveals a new type of spatiotemporal correlation between two quantum dynamics that originates from synchronized propagation in time under time-reversal symmetry. We show that quantum systems with such correlation can be utilized as a reference frame to distinguish certain dynamics indistinguishable under time-reversal symmetry.

2512.17467 2026-06-11 physics.optics 版本更新

An Integrated DFT-FDTD Design of Plasmon-Enhanced Lead-Free $CsSn$$_x$$Ge$$_{1-x}$$I$$_3$ Perovskite LEDs

无铅CsSn$_x$Ge$_{1-x}$I$_3$钙钛矿LED的等离激元增强集成DFT-FDTD设计

Shoumik Debnath, Sudipta Saha, Khondokar Zahin, Ying Yin Tsui, Md. Zahurul Islam

AI总结 提出DFT-FDTD框架,通过组分调控和等离激元增强优化无铅钙钛矿LED的光提取效率,发现CsSn$_{0.5}$Ge$_{0.5}$I$_3$在提取效率、Purcell增强和稳定性间取得最佳平衡。

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Journal ref
Materials Advances, 2026
AI中文摘要

CsSn$_x$Ge$_{1-x}$I$_3$作为无铅钙钛矿,因其可调带隙和稳定性,有望用于下一代近红外发射钙钛矿LED。然而,它们存在光提取效率低的问题,且这些材料的精确组分特定光学数据仍然稀缺。本研究提出了一个DFT-FDTD框架,通过组分调控和等离激元增强来优化光提取。首先,进行DFT计算以获得$x = 0, 0.25, 0.5, 0.75$和$1$的组分特定复折射率和消光系数值。结果表明,随着Ge含量增加,带隙从CsSnI$_3$的1.331 eV增加到CsGeI$_3$的1.927 eV,而折射率在2.2到2.6之间变化。然后,将这些光学常数作为FDTD模拟的输入,用于具有优化Au/SiO$_2$核壳纳米棒的PeLED结构以实现等离激元增强。对于CsSn$_{0.25}$Ge$_{0.75}$I$_3$,实现了12.1倍的Purcell增强,而CsSn$_{0.5}$Ge$_{0.5}$I$_3$的光提取效率达到25%。CsSnI$_3$的LEE增强达到36%,富Sn组分的发射体与等离激元共振的光谱重叠达到96%。设计指南表明,CsSn$_{0.5}$Ge$_{0.5}$I$_3$在提取效率(25%)、Purcell增强(5.3倍)、光谱重叠(93%)和氧化稳定性方面为可穿戴和柔性光电子应用提供了最佳平衡,而CsSn$_{0.25}$Ge$_{0.75}$I$_3$推荐用于优先考虑自发辐射速率的应用。

英文摘要

CsSn$_x$Ge$_{1-x}$I$_3$ as lead-free perovskites are promising for next generation NIR emitting perovskite LEDs due to their tunable bandgaps and stability. However, they suffer from poor light extraction efficiency, and accurate composition-specific optical data for these materials remain scarce. This study presents a DFT-FDTD framework to optimize light extraction via compositional tuning and plasmonic enhancement. First, DFT calculations were performed to obtain composition-specific complex refractive index and extinction coefficient values for $x = 0, 0.25, 0.5, 0.75$, and $1$. Results show bandgap increased from 1.331 eV for CsSnI$_3$ to 1.927 eV for CsGeI$_3$ with increasing Ge content, while refractive index ranges from 2.2 to 2.6 across compositions. These optical constants were then used as inputs for FDTD simulations of a PeLED structure with optimized Au/SiO$_2$ core-shell nanorods for plasmonic enhancement. A 12.1-fold Purcell enhancement was achieved for CsSn$_{0.25}$Ge$_{0.75}$I$_3$, while light extraction efficiency reached 25% for CsSn$_{0.5}$Ge$_{0.5}$I$_3$. LEE enhancement of 36% was obtained for CsSnI$_3$, and spectral overlap between emitter and plasmon resonance reached 96% for Sn-rich compositions. Design guidelines indicate CsSn$_{0.5}$Ge$_{0.5}$I$_3$ offers optimal balance of extraction efficiency (25%), Purcell enhancement (5.3$\times$), spectral overlap (93%), and oxidation stability for wearable and flexible optoelectronic applications, while CsSn$_{0.25}$Ge$_{0.75}$I$_3$ is recommended for applications prioritizing spontaneous emission rate.

2604.08447 2026-06-11 physics.ins-det hep-ex 版本更新

ML for the hKLM at the 2nd Detector

机器学习用于第二探测器的hKLM

Rowan Kelleher, Anselm Vossen

AI总结 本文利用图神经网络提升第二探测器中中性强子的能量测量和识别性能,提出加速光电模拟方法,并展示GNN在多目标优化中的应用。

Comments To be published in JINST as part of proceedings for AI4EIC2025. 6 pages, 4 figures

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AI中文摘要

本文研究将图神经网络应用于未来电子离子对撞机(EIC)第二探测器中的中性强子(K_L和中子)能量测量和识别任务。特别地,铁-荧光体采样 calorimeter 将提供中性强子的能量测量和识别,以及μ子与强子的分离。通过探测器模拟,粒子击中被表示为图,GNN被训练用于分类或预测。此外,我们开发了一种光电模拟参数化方法,使模拟速度提高20倍。我们发现GNN方法在相同任务上优于经典方法,并报告了calorimeter的能量和时间分辨率及识别准确度的预测。我们还展示了GNN方法整合到多目标优化框架中,通过自动化数据生成、GNN训练和探测器性能评估流程实现。我们利用优化来量化在高能和低能条件下改变探测器设计参数(如铁/荧光体厚度)时不同性能指标之间的权衡。

英文摘要

The present research applies Graph Neural-Networks (GNNs) for energy measurement and particle identification tasks for a proposed second detector at the future Electron Ion Collider (EIC). In particular, an iron-scintillator sampling calorimeter would provide neutral hadron ($K_L$ and neutron) energy measurements and identification, as well as separation of muons from hadrons. Using detector simulations, particle hits in the detector are represented as graphs, and a GNN is trained for either classification or prediction. Furthermore, we developed a parameterization of the scintillator optical photon simulation that yields a 20-fold speed up compared to the default simulation. We find that the GNN method outperforms classical methods at the same tasks, and we report projections for the energy and timing resolution, and identification accuracy of the calorimeter. We also present an integration of the GNN method into a Multi-Objective Optimization framework, enabled by an automated pipeline of data generation, GNN training, and detector performance evaluation. We utilize the optimization to quantify the tradeoffs between different performance metrics at high and low energies when changing the detector design parameters, such as the iron/scintillator thickness.

2604.06841 2026-06-11 physics.chem-ph cond-mat.str-el 版本更新

Spin-adapted neural network backflow for symmetry-preserving simulations of strongly correlated electrons

自旋自适应神经网络反流用于强关联电子的对称性保持模拟

Yunzhi Li, Zibo Wu, Bohan Zhang, Wei-Hai Fang, Zhendong Li

AI总结 提出自旋自适应神经网络反流(SA-NNBF)变分波函数,通过结合构型依赖空间轨道和压缩自旋本征函数,消除自旋污染,在氢链和铁硫簇中实现更低变分能,并在FeMoco活性空间模型中达到与自旋自适应DMRG竞争的能量。

Comments 10 pages, 5 figures

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AI中文摘要

强关联分子通常包含密集的低能自旋态流形,使得总自旋对称性对于预测性电子结构理论至关重要。神经网络量子态提供了灵活的变分波函数,但常用的费米子架构不强制这种对称性,因此可能收敛到具有误导性能量和性质的自旋污染态。这里我们引入第二量子化中的自旋自适应神经网络反流(SA-NNBF)拟设,它结合了构型依赖的空间轨道和压缩的自旋本征函数。自旋本征函数的投影张量压缩方案和粒子-空穴表示使得使用SA-NNBF的变分蒙特卡罗计算对于包含超过一百个电子的活性空间变得实用。在氢链和铁硫簇中,SA-NNBF消除了自旋污染,并且一致地实现了比具有可比参数数量的标准NNBF更低的变分能量。对于FeMoco的CAS(113e,76o)活性空间模型,SA-NNBF产生了一个高度紧凑的自旋自适应变分态,在键维数$D=10000$时实现了与最近自旋自适应DMRG计算竞争的能量,同时使用的参数数量少几个数量级。我们的工作为开发用于化学现实强关联电子的自旋对称性保持神经网络量子态建立了一个通用框架。

英文摘要

Strongly correlated molecules often contain dense manifolds of low-lying spin states, making total-spin symmetry essential for predictive electronic-structure theory. Neural-network quantum states provide flexible variational wavefunctions, but commonly used fermionic architectures do not enforce this symmetry and can therefore converge to spin-contaminated states with misleading energies and properties. Here we introduce a spin-adapted neural-network backflow (SA-NNBF) ansatz in second quantization, which combines configuration-dependent spatial orbitals with a compressed spin eigenfunction. A projected tensor compression scheme for spin eigenfunctions and a particle-hole representation make variational Monte Carlo calculations with SA-NNBF practical for active spaces containing more than one hundred electrons. Across hydrogen chains and iron-sulfur clusters, SA-NNBF eliminates spin contamination and consistently achieves lower variational energies than standard NNBF with a comparable number of parameters. For the CAS(113e,76o) active-space model of FeMoco, SA-NNBF yields a highly compact spin-adapted variational state, achieving an energy competitive with recent spin-adapted DMRG calculations at bond dimension $D=10000$ while using orders of magnitude fewer parameters. Our work establishes a general framework for developing spin-symmetry-preserving neural-network quantum states for chemically realistic strongly correlated electrons.

2604.03429 2026-06-11 astro-ph.HE astro-ph.SR 版本更新

Milliarcsecond-scale spectrum of the persistent radio source associated with FRB 20190417A and constraints for FRB 20181030A

与FRB 20190417A相关的持续射电源的VLBI谱

G. Bruni, L. Piro, Y. -P. Yang, L. Nicastro, A. Rossi, E. Palazzi, E. Maiorano, S. Savaglio, B. Zhang

AI总结 利用EVN在5和8 GHz观测,确认FRB 20190417A的致密射电源具有非热性质和平坦谱(α=-0.19±0.29),支持星云起源,并限制FRB 20181030A的候选PRS具有陡谱。

Comments Accepted for publication in A&A Letters

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AI中文摘要

我们旨在确认与重复快速射电暴(FRBs)相关的候选持续射电源(PRSs)的致密性质并限制其射电谱。我们利用欧洲VLBI网络(EVN)在5和8 GHz对近期VLA巡天中识别的两个候选体进行了观测。我们在毫角秒分辨率下测量了流量密度和上限,并将其与已发表的低频VLBI数据结合,以推导谱约束。我们在5 GHz探测到与FRB 20190417A相关的致密源,流量密度为$150\pm45$ uJy,而在8 GHz未探测到。该源未分辨,亮温度$T_{\rm b}>10^{5}$ K,证实其非热性质。将我们的测量与1.4 GHz的VLBI数据结合,我们推导出谱指数$\alpha = -0.19 \pm 0.29$,与近乎平坦的谱一致。这使得FRB 20190417A成为第二个利用VLBI数据约束谱指数的PRS。推断的光度将该源置于提出的$L_{\nu}$-|RM|关系上。包含该源后,散点为$\sigma_\Delta = 0.65$,对应$\hat{\alpha}|\epsilon| = 1.5 \pm 0.7$,与自由膨胀阶段的前向激波或年轻脉冲星风云一致。对于与FRB 20181030A相关的候选PRS,我们报告了5 GHz的80 uJy和8 GHz的150 uJy上限,对应$L_{5\\,\mathrm{GHz}} \lesssim 3.8 \times 10^{25}\\ {\rm erg\\ s^{-1}\\ Hz^{-1}}$,如果VLA发射来自致密成分,则意味着陡谱指数($\alpha \lesssim -1.2$)。我们的结果强调了VLBI在分离FRB引擎的致密发射中的重要性,并提供了毫角秒分辨率下PRS的少数谱约束之一。FRB 20190417A与$L_{\nu}$-|RM|关系的一致性支持持续发射的星云起源。

英文摘要

We aim to confirm the compact nature and constrain the radio spectra of candidate persistent radio sources (PRSs) associated with repeating fast radio bursts (FRBs). We performed European VLBI Network (EVN) observations at 5 and 8 GHz targeting two candidates identified in a recent VLA survey. We measured flux densities and upper limits at milliarcsecond resolution and combined them with published VLBI data at lower frequencies to derive spectral constraints. We detect a compact source associated with FRB 20190417A at 5 GHz with a flux density of $150\pm45$ uJy, while no detection is obtained at 8 GHz. The source is unresolved and has a brightness temperature $T_{\rm b}>10^{5}$ K, confirming its non-thermal nature. Combining our measurement with VLBI data at 1.4 GHz, we derive a spectral index $α= -0.19 \pm 0.29$, consistent with a nearly flat spectrum. This makes FRB 20190417A only the second PRS with a spectral index constrained using VLBI data. The inferred luminosity places the source on the proposed $L_ν$-|RM| relation. Including this source yields a scatter of $σ_Δ= 0.65$, corresponding to $\hatα|ε| = 1.5 \pm 0.7$, consistent with forward shocks in the free-expansion phase or young pulsar wind nebulae. For the candidate PRS associated with FRB 20181030A, we report upper limits of 80 uJy at 5 GHz and 150 uJy at 8 GHz, corresponding to $L_{5\,\mathrm{GHz}} \lesssim 3.8 \times 10^{25}\ {\rm erg\ s^{-1}\ Hz^{-1}}$, and implying a steep spectral index ($α\lesssim -1.2$) if the VLA emission arises from a compact component. Our results highlight the importance of VLBI in isolating compact emission from FRB engines and provide one of the few spectral constraints for PRSs at milliarcsecond resolution. The consistency of FRB 20190417A with the $L_ν$-|RM| relation supports a nebular origin for the persistent emission.

2511.04661 2026-06-11 astro-ph.CO astro-ph.IM 版本更新

unimpeded: A Public Grid of Nested Sampling Chains for Cosmological Model Comparison and Tension Analysis

unimpeded: 用于宇宙学模型比较和张力分析的公共嵌套采样链网格

Dily Duan Yi Ong, Will Handley

AI总结 发布公共Python库unimpeded,提供预计算嵌套采样和MCMC链,对8个宇宙学模型和39个数据集进行系统分析,发现ΛCDM模型最受青睐,并量化了DES与Planck、SH0ES与Planck之间的显著张力。

Comments 49 pages, 13 figures. Version 3: Revised in response to the JCAP editor's report. Added Section 3.2.12 on the treatment of nuisance parameters in the evidence and tension calculations. Results unchanged

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AI中文摘要

贝叶斯推断是现代宇宙学的核心,然而全面的模型比较和张力量化对许多研究人员来说仍然计算成本高昂。为解决这一问题,我们发布了$\texttt{unimpeded}$,一个公开可用的Python库和数据存储库,提供预计算的嵌套采样和MCMC链。我们利用这一资源,对包括$\Lambda$CDM及其七个扩展在内的八个宇宙学模型网格,以及包括单个探测器和它们的两两组合在内的39个数据集进行了系统分析。我们的模型比较显示,尽管单个数据集对模型扩展表现出不同的偏好,但在组合分析中最常偏好基础$\Lambda$CDM模型,总体趋势表明当探测数据组合时,新物理的证据被稀释。利用五种互补统计量,我们量化了张力,发现最显著的是DES与Planck之间($\sigma=3.57\pm0.10$)以及SH0ES与Planck之间($\sigma=3.27\pm0.10$)在$\Omega_k\Lambda$CDM模型中的张力。我们将$S_8$张力表征为高维($d_G=4.87\pm0.79$),并且在某些扩展模型中部分可解,而哈勃张力是低维的,并在整个模型空间中持续存在。在组合存在张力的数据集时应谨慎。托管在Zenodo上的$\texttt{unimpeded}$数据产品为可重复的宇宙学分析提供了强大资源,并强调了$\Lambda$CDM模型在此全面基准编译中的稳健性。

英文摘要

Bayesian inference is central to modern cosmology, yet comprehensive model comparison and tension quantification remain computationally prohibitive for many researchers. To address this, we release $\texttt{unimpeded}$, a publicly available Python library and data repository providing pre-computed nested sampling and MCMC chains. We apply this resource to conduct a systematic analysis across a grid of eight cosmological models, including $Λ$CDM and seven extensions, and 39 datasets, including individual probes and their pairwise combinations. Our model comparison reveals that whilst individual datasets show varied preferences for model extensions, the base $Λ$CDM model is most frequently preferred in combined analyses, with the general trend suggesting that evidence for new physics is diluted when probes are combined. Using five complementary statistics, we quantify tensions, finding the most significant to be between DES and Planck ($σ=3.57\pm0.10$) and SH0ES and Planck ($σ=3.27\pm0.10$) within $Ω_kΛ$CDM. We characterise the $S_8$ tension as high-dimensional ($d_G=4.87\pm0.79$) and partially resolvable in certain extended models, whereas the Hubble tension is low-dimensional and persists across the model space. Caution should be exercised when combining datasets in tension. The $\texttt{unimpeded}$ data products, hosted on Zenodo, provide a powerful resource for reproducible cosmological analysis and underscore the robustness of the $Λ$CDM model against this comprehensive benchmark compilation.

2604.01301 2026-06-11 quant-ph math-ph math.MP 版本更新

Numerically Optimizing Shortcuts to Adiabaticity: A Hybrid Control Strategy

数值优化绝热捷径:一种混合控制策略

Bo Xing, Jesús G. Parejo, Sofía Martínez-Garaot, Paola Cappellaro, Mikel Palmero

AI总结 结合解析绝热捷径与数值优化方法,提出混合控制策略,在离子分离问题中实现高达三个数量级的性能提升,且不增加实验成本。

Comments 24 pages, 9 figures

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Journal ref
Computer Physics Communications 327, 110246 (2026)
AI中文摘要

实现快速、无激发的量子控制是现代量子技术中的一个关键挑战。在许多情况下,绝热捷径能够实现快速的绝热类协议,但在复杂系统中确定满足实际约束的控制参数往往具有挑战性。在这里,我们将解析绝热捷径方法与多种数值优化方法相结合,以提升协议的性能。作为这种混合方法的原理验证,我们研究了一个特别复杂的控制问题——两个捕获离子的分离。我们表明,这种解析-数值方法,以及通过多种次优解获得的物理洞察,导致在复杂景观中探索新解,从而实现了高达三个数量级的改进。此外,从实验角度来看,这种改进没有带来额外的成本。

英文摘要

Achieving fast, excitation-free quantum control is a vital challenge in modern quantum technologies. In many cases, shortcuts to adiabaticity enable fast adiabatic-like protocols, yet determining control parameters that satisfy practical constraints is often challenging in complex systems. Here, we combine an analytical shortcut to adiabaticity approach with several numerical optimization methods to boost the performance of the protocol. As a proof-of-principle for this hybrid approach, we study a particularly intricate control problem, the separation of two trapped ions. We show that this analytical-numerical approach, along with the physical insight gained through the variety of suboptimal solutions, leads to the exploration of new solutions in a complex landscape that yield improvements of up to 3 orders of magnitude. Moreover, this improvement comes with no additional cost from an experimental point of view.