arXivDaily arXiv每日学术速递 周一至周五更新
重置
全部学科分类 2031
2606.06237 2026-06-05 astro-ph.IM gr-qc

Sensitivity Limits and Operational Threshold Calibration for DINOv2-based Gravitational-Wave Glitch Characterization: A Strain-Domain Mock Data Challenge on LIGO O4a

基于DINOv2的引力波毛刺表征的灵敏度极限与运行阈值校准:LIGO O4a应变域模拟数据挑战

Luca Cirfeta

AI总结 通过LIGO O4a应变域模拟数据挑战,研究DINOv2无监督引力波毛刺检测管道的灵敏度极限,发现全局平均池化导致对局部微结构不敏感,并提出了基于补丁级评分和多尺度窗口的改进方向。

Comments 7 pages, 6 tables, 3 figures. Companion paper to arXiv:2605.28572. Pipeline and MDC code: https://github.com/lucacirfeta/dante-gravi-signal-ml

详情
AI中文摘要

我们提出了一项模拟数据挑战(MDC),以表征gravi-signal-ml管道(Cirfeta 2026)用于无监督引力波毛刺检测的灵敏度极限。将八种形态族的应变域合成注入到公开的LIGO O4a L1数据中,揭示了两个阈值依赖的灵敏度区域。使用会话自适应动态阈值(tau_dyn = mu_bg - 2.5 * sigma_bg),管道在匹配滤波信噪比 >= 70时恢复视觉各向异性形态(Butterfly, ZSweep),达到召回率=1.0,但假阳性率(FPR)在各会话中不受控制。对完整O4a嵌入分布(N = 188,142个片段)的表征揭示了极端非高斯性(偏度 = -4.12,超额峰度 = 15.38,Shapiro-Wilk p值接近0),左尾由广义极值(GEV)分布最佳拟合。在经验5x10^-5分位数(FPR < 0.01%)处校准的统计严格运行阈值(tau_op = 0.874)下,MDC在所有测试信噪比水平下对所有八种形态的召回率均为0,包括窄带结构(HarmonicComb, NarrowChirp)和脉冲瞬变(AsymBlip),信噪比高达430。我们将这种不敏感性归因于DINOv2 [CLS]令牌的全局平均池化,它稀释了占据频谱图37x37补丁网格一小部分(<5%)的信号。Cirfeta(2026)的零结果被有条件地重新解释:它确认了没有新的大尺度结构,但不能排除局部微结构。这些发现为下一代基于ViT的管道使用补丁级评分和多尺度窗口提供了定量路线图。

英文摘要

We present a Mock Data Challenge (MDC) to characterize the sensitivity limits of the gravi-signal-ml pipeline (Cirfeta 2026) for unsupervised gravitational-wave glitch detection. Strain-domain synthetic injections of eight morphological families into public LIGO O4a L1 data reveal two threshold-dependent sensitivity regimes. With a session-adaptive dynamic threshold (tau_dyn = mu_bg - 2.5 * sigma_bg), the pipeline recovers visually anisotropic morphologies (Butterfly, ZSweep) at matched-filter SNR >= 70, reaching Recall = 1.0, though the False Positive Rate (FPR) remains uncontrolled across sessions. Characterization of the full O4a embedding distribution (N = 188,142 segments) reveals extreme non-Gaussianity (skewness = -4.12, excess kurtosis = 15.38, Shapiro-Wilk p-value near 0), with the left tail best modeled by a Generalized Extreme Value (GEV) distribution. Under a statistically rigorous operational threshold (tau_op = 0.874) calibrated at the empirical 5x10^-5 quantile (FPR < 0.01%), the MDC yields Recall = 0 for all eight morphologies at all tested SNR levels, including narrowband structures (HarmonicComb, NarrowChirp) and impulsive transients (AsymBlip) at SNR up to 430. We trace this insensitivity to the global average pooling of the DINOv2 [CLS] token, which dilutes signals occupying a small fraction (<5%) of the spectrogram's 37x37 patch grid. The null result of Cirfeta (2026) is conditionally reinterpreted: it confirms the absence of novel macro-structures but cannot exclude localized micro-structures. These findings provide a quantitative roadmap for next-generation ViT-based pipelines using patch-level scoring and multi-scale windowing.

2606.06234 2026-06-05 astro-ph.SR astro-ph.EP astro-ph.IM

gr8stars II : judgement day for spectroscopic parameter model systematics

gr8stars II : 光谱参数模型系统误差的审判日

Alix Violet Freckelton, Annelies Mortier, Megan Bedell, Michael Cretignier, Jared R. Kolecki, Andreas J. Korn, Sérgio G. Sousa, Maria Tsantaki, John M. Brewer, Lars A. Buchhave, Guy R. Davies, J. I. González Hernández, Sam Morrell, Martin B. Nielsen, Vera Maria Passegger, Andreas Quirrenbach, Arpita Roy, Nuno C. Santos, A. Suárez Mascareño, Christopher Allan Watson, Lily L. Zhao

AI总结 使用SOPHIE光谱仪对585颗明亮FGK矮星进行五种光谱方法分析,发现有效温度、表面重力和金属丰度的典型散度显著大于平均精度误差,并通过等时线拟合确定质量、半径和年龄,评估了对系外行星参数的影响。

Comments Accepted for publication in MNRAS

详情
AI中文摘要

天体物理学的许多领域,包括系外行星研究,依赖于精确且准确的恒星参数。这要求这些参数的不确定性真实反映所有偏差和系统误差。在 exttt{gr8stars}合作项目的第二项工作中,我们选取了来自SOPHIE光谱仪的585颗明亮FGK矮星的高分辨率、高信噪比光谱。我们使用五种不同的光谱方法确定每颗恒星的有效温度、表面重力和金属丰度,并额外使用一种方法进行比较。我们发现 eff的典型散度为76 K,\logg为0.14 dex, eh为0.07 dex。这些偏差显著大于这些参数的平均精度误差。此外,我们使用等时线拟合,利用所有结果作为输入,确定了所有585颗恒星的质量、半径和年龄。我们将第一篇 exttt{gr8stars}论文中通过SED拟合确定的半径与本工作的等时线半径进行比较,同时比较等时线\logg与光谱\logg。研究了使用不同光谱方法导致的质量和半径散度,并将其传播到系外行星参数。发现行星半径($\lesssim$ 3 \%)和质量($\lesssim$ 5\%)的诱导分数不确定度低于文献中通常报道的值。我们估计行星平衡温度分数不确定度的下限约为4\%,这是一个目前在文献中未充分体现的噪声基底。

英文摘要

Many areas of astrophysics, including exoplanetary studies, rely on precise and accurate stellar parameters. This demands that uncertainties on these parameters truly reflect all biases and systematics. Within this second work of the \texttt{gr8stars} collaboration, we take a set of 585 bright FGK dwarfs with high resolution, high signal-to-noise ratio spectra from the SOPHIE spectrograph. We determine stellar effective temperature, surface gravity, and metallicity using five different spectroscopic methods for each star, with an additional method used for comparisons. We find a typical scatter of 76 K in \teff, 0.14 dex in \logg, and 0.07 dex in \feh. These deviations are significantly larger than the average precision error on these parameters. We furthermore use isochrone fitting to determine mass, radius, and age for all 585 stars, using input from all results. We use the radii determined by SED fitting in the first \texttt{gr8stars} paper as a comparison to our isochronal radii from this work, in addition to comparing the isochronal \logg to spectroscopic \logg. The scatter in mass and radius from the use of different spectroscopic methods is investigated and propagated to exoplanetary parameters. The induced fractional uncertainties in planetary radius ($\lesssim$ 3 \%) and mass ($\lesssim$ 5\%) are found to be below those typically found in the literature. We estimate a lower limit on planetary equilibrium temperature fractional uncertainty of $\approx$ 4\%, a noise floor that is currently not sufficiently represented in the literature.

2606.06232 2026-06-05 physics.plasm-ph physics.acc-ph

Plasma wakefield dynamics of self-generated electron bunch trains

自产生电子束团的等离子体尾场动力学

Salome Benracassa, Sheroy Tata, Yinren shou, Aaron Liberman, Victor Malka

AI总结 本研究通过激光驱动尾场加速器中的下坡注入产生具有周期性能量间隔的准单能电子束团,利用尾场的相对论性延长和相空间旋转实现能量压缩,并通过粒子模拟揭示其形成与演化机制。

Comments 6 pages,5 figures

详情
AI中文摘要

激光等离子体加速器可以在厘米尺度上提供高能量、准单能的电子束。本文报告了在激光驱动尾场加速器中通过下坡注入产生具有周期性能量间隔的窄带准单能电子束团。能量周期性通过加速阶段尾场的相对论性延长形成,而空间周期性则通过注入多个等离子体周期获得。在加速器末端,通过相空间旋转对每个束团进行能量压缩,产生光谱中狭窄的周期性尖峰。实验观察得到了粒子模拟的支持,模拟再现了周期性束团的形成和演化,为理解底层等离子体动力学提供了见解。

英文摘要

Laser plasma accelerators can deliver high-energy, quasi-monoenergetic electron beams over centimeter-scale distances. In this work, we report on the generation of narrow, quasi-monoenergetic electron bunch trains with periodic energy spacing issued from downramp injection in a laser driven wakefield accelerator. The periodicity in energy is shaped via relativistic lengthening of the wakefield during the acceleration phase, while the spatial periodicity is obtained via injection into multiple plasma periods. At the end of the accelerator, a rotation in phase-space is performed to compress each bunch in energy, producing narrow periodic spikes in the spectrum. The experimental observations are supported by particle-in-cell simulations, which reproduce the formation and evolution of the periodic bunch trains, providing an insight into the underlying plasma dynamics.

2606.06231 2026-06-05 math.PR

Sensitivity of SDE Solutions to Perturbations of the Diffusion and Drift

SDE解对扩散和漂移扰动的敏感性

Jeremiah Birrell

AI总结 通过信息论不确定性量化界、函数不等式和精心选择的耦合辅助SDE,提出一种方法,对随机微分方程解关于漂移和扩散变化的敏感性进行非渐近界估计,并适用于时间平均和指数折扣可观测量的期望,以及线性抛物型PDE,对不变测度的1-Wasserstein距离给出最优缩放界。

Comments 25 pages

详情
AI中文摘要

我们开发了一种方法,通过结合信息论不确定性量化界、函数不等式和精心选择的耦合辅助随机微分方程(SDE),来界定SDE解对漂移$F$和扩散$\sigma$变化的敏感性。该方法能够产生在$T\to \infty$极限下表现良好的非渐近界,并且不需要$F$和$\sigma$的扰动很小。我们的方法适用于时间平均和指数折扣可观测量的期望,也产生线性抛物型PDE的敏感性界。当应用于平稳解和Lipschitz可观测量时,我们的结果给出了不变测度之间的$1$-Wasserstein距离的界,该界在每个误差项中具有最优缩放。本方法显著扩展了先前的信息论SDE敏感性界,后者仅适用于漂移的扰动。

英文摘要

We develop a method for bounding the sensitivity of solutions to stochastic differential equations (SDEs) to changes in the drift, $F$, and diffusion, $σ$, by using a combination of information-theoretic uncertainty quantification bounds, functional inequalities, and judiciously chosen coupled auxiliary SDEs. The method is capable of producing non-asymptotic bounds which are well behaved in the $T\to \infty$ limit and does not require the perturbations to $F$ and $σ$ to be small. Our approach applies to expectations of both time-averaged and exponentially discounted observables and also produces sensitivity bounds for linear parabolic PDEs. When applied to stationary solutions and Lipschitz observables, our results produce bounds on the $1$-Wasserstein distance between invariant measures which have optimal scaling in each error term. The present method significantly expands on prior information-theoretic SDE sensitivity bounds, which are only applicable to perturbations of the drift.

2606.06230 2026-06-05 astro-ph.EP

Peas and USPs: Can Stellar Spindown and Peas in a Pod Replicate Ultra-Short-Period Planet Characteristics?

豌豆与USP:恒星自转减慢和豌豆荚结构能否复制超短周期行星的特征?

Adam Distler, Juliette Becker

AI总结 通过拉普拉斯-拉格朗日长期理论,研究恒星自转减慢对豌豆荚行星系统的影响,发现仅靠自转减慢无法使内行星解耦,需要内行星向内迁移才能实现长期共振穿越。

Comments 11 pages, 4 figures. Accepted in ApJ

详情
AI中文摘要

豌豆荚系统在系外行星系统中普遍存在,具有规则的行星间距和相似的行星大小。相比之下,超短周期行星显示出与豌豆荚系统的明显差异,包括更高的互倾角、年龄和行星大小。利用拉普拉斯-拉格朗日长期理论,我们研究了恒星自转减慢解耦豌豆荚系统的能力。我们发现,对于预期的恒星$J_2$演化,具有规则间距的严格豌豆荚系统无法经历长期共振穿越,相反,我们需要内行星向内迁移才能经历这种共振穿越。因此,豌豆荚系统没有内边界,系统总是会穿越长期共振并解耦内行星。利用恒星演化模型预期的$J_2$演化轨迹,我们发现了预期共振穿越时间的多样性,强调了利用这一框架测试迁移路径和初始恒星倾角的能力。

英文摘要

Peas-in-a-Pod (PIAP) systems have been shown to be common across exoplanet systems, with regular planet spacings and similar planet sizes. In contrast, ultra-short-period planets have displayed distinct differences from PIAP systems, including higher mutual inclinations, ages, and planet sizes. Using Laplace-Lagrange secular theory, we investigate the ability of stellar spindown to decouple PIAP systems. We find that strictly PIAP systems with regular spacings cannot undergo secular resonance crossings for the expected stellar $J_2$ evolution, and that we instead require the inner planet to migrate inward to undergo this resonance crossing. As a result, there is no inner edge to PIAP systems where systems will always cross a secular resonance and decouple the inner planet. Using expected $J_2$ evolution tracks from stellar evolution models, we find a diversity of expected resonance crossing times, highlighting the ability to test migration pathways and initial stellar obliquities using this framework.

2606.06229 2026-06-05 math.FA

Extension of Sobolev functions on balls in infinite dimensions

无限维球上Sobolev函数的延拓

Zhouzhe Wang, Xu Zhang, Shiliang Zhao

AI总结 提出全新方法证明存在有界Sobolev延拓算子,解决了文献中的开放问题。

Comments 18 pages

详情
AI中文摘要

我们使用一种全新的方法证明了有界Sobolev延拓算子$E:W^{p,1}\left( B,P ight) ightarrow W^{p,1}\left( \ell^{2} ,P ight)$的存在性,其中$B\subset \ell^{2}$是单位球,$P$是$\ell^{2}$上的任意非平凡中心高斯测度。这解决了文献中提出的一个开放问题。

英文摘要

We prove the existence of a bounded Sobolev extension operator $E:W^{p,1}\left( B,P \right) \rightarrow W^{p,1}\left( \ell^{2} ,P \right)$ using a completely new method, where $B\subset \ell^{2}$ is the unit ball and $P$ is any non-trivial centered Gaussian measure on $\ell^{2}$. This solves an open problem posed in the literatures.

2606.06226 2026-06-05 astro-ph.GA

A New Member of the Fast and Furious Family: A Relativistic and Time-Variable UV Outflow in a Luminous Quasar

快与怒家族的新成员:明亮类星体中相对论性且时变的紫外外流

Lucas M. Seaton, Patrick B. Hall, Liliana Flores, Paola Rodríguez Hidalgo, Marianna Veltri, Zezhou Zhu, Javier Serna, W. Niel Brandt, Scott Anderson, Roberto J. Assef, Eduardo Bañados, Catherine J. Grier, Yasaman Homayouni, Sean Morrison, C. Alenka Negrete, Amy L. Rankine, Jessie Runnoe, Donald P. Schneider, Yue Shen, Matthew Temple, Benny Trakhtenbrot, Jonathan R. Trump, Erik Weiss

AI总结 报告在类星体SDSS J231854.31+243954.2中探测到速度高达-90,000 km/s的紫外吸收外流,通过变动的C IV和Si IV吸收线发现,并估算其质量损失和动能光度比,表明可能对宿主星系产生显著反馈。

Comments 40 pages, 12 figures, 10 tables, published in the Astrophysical Journal

详情
Journal ref
The Astrophysical Journal, Volume 1004, Number 1, 49, June 2026
AI中文摘要

我们报告了在紫外波段首次探测到的最快类星体外流,通过射电宁静类星体SDSS J231854.31+243954.2(J2318)中速度从-77,000 km/s到至少-90,000 km/s的变动的C IV和Si IV吸收线发现。J2318在静止系紫外波段是一个弱线类星体,但Gemini GNIRS光谱揭示了Hα红移z=2.6781±0.0004。二十年的测光时间序列显示g波段峰值变化为0.5星等。C IV外流在跨越约2.2静止系年的三个历元中单调增强。如此高速外流的存在意味着类星体外流模型必须能够将气体加速到0.3c,同时仍保留C IV和Si IV离子,或者使被加速到0.3c的气体中形成C IV和Si IV离子。维里估计显示黑洞质量为1.65×10^9 M⊙,对应的爱丁顿光度为2.4×10^47 erg/s,爱丁顿比为0.45。在非常保守的假设下,仅紫外吸收外流的质量损失率估计>0.82 M⊙/yr,动能光度比L_kin/L_bol≥0.75%。该下限刚好超过通常认为对宿主星系产生显著反馈的阈值。与PDS 456(唯一已知的另一个具有0.3c紫外吸收外流的类星体)的比较表明,真实的M˙和L_kin/L_bol可能高出两个数量级。

英文摘要

We report the fastest quasar outflow first detected in the ultraviolet, via variable C IV and Si IV absorption at outflow velocities $-77,000$ km s$^{-1}$ to at least $-90,000$ km s$^{-1}$, in the radio-quiet quasar SDSS J231854.31+243954.2 (J2318). J2318 is a weak-lined quasar in the rest-frame ultraviolet, but Gemini GNIRS spectroscopy reveals an H$α$ redshift of $z=2.6781\pm0.0004$. A twenty-year photometric time series shows peak-to-peak variability of 0.5 mag in the $g$ band. The C IV outflow strengthened monotonically over three epochs spanning $\sim$2.2 rest-frame years. The existence of such a high-velocity outflow implies that models of quasar outflows must be able to either accelerate gas to $0.3c$ while still preserving C IV and Si IV ions, or enable the formation of C IV and Si IV ions in gas which has been accelerated to $0.3c$. Virial estimates reveal a black-hole mass of $1.65\times10^9~M_\odot$, which leads to an Eddington luminosity and Eddington ratio of $2.4\times10^{47}$ erg s$^{-1}$ and $0.45$, respectively. Using very conservative assumptions, the UV-absorbing outflow alone has an estimated mass loss of $>0.82~M_\odot~{\rm yr}^{-1}$ and a kinetic luminosity ratio $L_{kin}/L_{bol}\geq0.75$%. The lower limit is just above the threshold usually cited for significant feedback on the host galaxy. Comparison to PDS 456, the only other known quasar with a UV-absorbing outflow at $0.3c$, suggests that the true $\dot{M}$ and $L_{kin}/L_{bol}$ could be up to two orders of magnitude larger.

2606.06222 2026-06-05 math.NT math.CO

No three algebraic conjugates of degree sixteen sum to zero

无十六次代数共轭三元和为零

Žygimantas Baronėnas, Paulius Drungilas, Jonas Jankauskas

AI总结 通过分类16个顶点上6度顶点传递图,证明不存在16次代数数使得其三个共轭之和为零,结合已有结果得出最小可能的次数d=20。

详情
AI中文摘要

设$d$为不被3整除的最小正整数,使得存在一个$\mathbb{Q}$上的$d$次代数数,其某三个代数共轭之和为零。利用16个顶点上6度顶点传递图的分类,我们证明$d eq 16$。结合Dubickas、Smyth和Stong \cite{DubickasSmyth2006}、Dubickas和Jankauskas \cite{DubickasJankauskas2015}以及Virbalas \cite{Virbalas2025a}的结果,这推出$d=20$。

英文摘要

Let $d$ be the smallest positive integer, not divisible by $3$, for which there exists an algebraic number over $\mathbb{Q}$ of degree $d$ whose some three algebraic conjugates sum to zero. Employing the classification of vertex-transitive graphs on 16 vertices of degree 6, we prove that $d\neq 16$. This, combined with results obtained by Dubickas, Smyth and Stong \cite{DubickasSmyth2006}, Dubickas and Jankauskas \cite{DubickasJankauskas2015} and Virbalas \cite{Virbalas2025a}, implies that $d=20$.

2606.06221 2026-06-05 hep-th hep-ph

Chiral symmetry breaking in models with unconventional supersymmetry

具有非常规超对称的模型中的手征对称性破缺

Pedro D. Alvarez, Cristian Villavicencio, Jorge Zanelli

AI总结 本文研究基于超李代数$su(2,2|3)$的几何规范理论中,由非最小耦合和挠率产生的费米子自相互作用导致的手征对称性破缺和费米子质量生成。

Comments 18 pages, 2 figures

详情
AI中文摘要

我们研究基于超李代数$su(2,2|3)$的几何构造规范理论中的动力学质量生成,其中引力、杨-米尔斯场和费米子作为单一规范联络的分量被统一。该模型不包含基本标量场,也没有特设的四费米子相互作用。相反,费米子自相互作用不可避免地源于理论的几何结构,通过与统一联络相关的非最小耦合和挠率。在约化到有效低能描述后,这些相互作用产生Nambu-Jona-Lasinio型势,触发手征对称性破缺并形成费米子质量间隙。在此框架下,质量生成作为底层规范-几何和代数结构的直接结果出现,而非独立的动力学假设。

英文摘要

We investigate dynamical mass generation in a geometrically constructed gauge theory based on the super Lie algebra $su(2,2|3)$, in which gravity, Yang-Mills fields, and fermions are unified as components of a single gauge connection. The model contains no elementary scalar fields and no ad hoc four-fermion interactions. Instead, fermionic self-interactions arise unavoidably from the geometric structure of the theory, through nonminimal couplings and torsion associated with the unified connection. Upon reduction to an effective low-energy description, these interactions generate a Nambu-Jona-Lasinio--type potential that triggers chiral symmetry breaking and the formation of a fermion mass gap. In this framework, mass generation emerges as a direct consequence of the underlying gauge-geometric and algebraic structure, rather than as an independent dynamical assumption.

2606.06220 2026-06-05 math.DG

Betti and Hodge numbers of solvmanifolds arising from integer polynomials

由整数多项式产生的可解流形的Betti数和Hodge数

Adrián Andrada, Valentina Chaves

AI总结 研究由整系数多项式构造的三类完全可解几乎阿贝尔可解流形的de Rham上同调,在多项式满足满秩或拟满秩条件下计算Betti数和Poincaré多项式,并通过与广义Nakamura流形的等同计算复可解流形的Hodge数。

Comments Comments are welcome!

详情
AI中文摘要

我们遵循Andrada和Barberis的工作,研究由具有正不同根且乘积为1的首一整系数多项式构造的三类完全可解几乎阿贝尔可解流形(称为基本、复和超复)的de Rham上同调。在此类多项式的两个代数限制(满秩和拟满秩条件)下,我们计算了这些流形的Betti数和Poincaré多项式。此外,通过将它们与Cattaneo和Tomassini最近引入的广义Nakamura流形等同,我们研究了复可解流形的Dolbeault上同调。在格满足适当条件的情况下,我们计算了它们的Hodge数,这些数在满秩情况下表现出与帕斯卡三角形相关的组合结构,而在拟满秩情况下则由显式生成多项式描述。

英文摘要

We study the de Rham cohomology of three families of completely solvable almost abelian solvmanifolds (called basic, complex, and hypercomplex) constructed from a monic integer polynomial with positive distinct roots whose product equals 1, following the work of Andrada and Barberis. Under two algebraic restrictions on such polynomials (the full rank and quasi full rank conditions) we compute the Betti numbers and Poincaré polynomials of these manifolds. Moreover, we study the Dolbeault cohomology of the complex solvmanifolds by identifying them with generalized Nakamura manifolds recently introduced by Cattaneo and Tomassini. Assuming a suitable condition on the lattice, we compute their Hodge numbers, which exhibit a combinatorial structure related to Pascal's triangle in the full rank setting, and are described by explicit generating polynomials in the quasi full rank case.

2606.06216 2026-06-05 math.CO

Tighter Bounds on the Degree-Truncated Choice Number of Planar Graphs

平面图的度截断选择数的更紧界

Huijuan Xu, Huan Zhou, Jialu Zhu, Xuding Zhu

AI总结 本文研究3连通非完全平面图族的度截断选择数,将上界从12改进到11,下界从9改进到10,并猜想该值为10,同时验证了当度数≥11的顶点诱导子图是4-可选时猜想成立。

Comments 15 pages, 5 figures

详情
AI中文摘要

假设$G$是一个图,$k$是一个正整数。定义$f:V(G)\to \mathbb{N}$为$f(v)=\min\{k,d_G(v)\}$。如果$G$是$f$-可选的,则称$G$是度截断$k$-可选的。$G$的度截断选择数为$\operatorname{ch}^{\text{\st{d}}}(G) = \min\{k: G \text{ 是度截断 $k$-可选的}\}$。对于图族$\mathcal{G}$,$\operatorname{ch}^{\text{\st{d}}}(\mathcal{G}) = \max\{\operatorname{ch}^{\text{\st{d}}}(G):G \in \mathcal{G}\}$。令$\mathcal{P}$表示3连通非完全平面图的族。Richter在2008年问是否$ch^{\text{\st{d}}}(\mathcal{P}) \le 6$。2025年,Zhou、Zhu和Zhu给出了否定回答,并证明了$8 \le ch^{\text{\st{d}}}(\mathcal{P}) \le 16$。该结果被Jiang、Xu、Xu和Zhu改进为$9 \le ch^{\text{\st{d}}}(\mathcal{P}) \le 12$。在本文中,我们进一步改进结果,证明$10 \le \operatorname{ch}^{\text{\st{d}}}(\mathcal{P}) \le 11$。我们猜想$\operatorname{ch}^{\text{\st{d}}}(\mathcal{P}) =10$,并且对于$\mathcal{P}$中那些度数至少为11的顶点诱导子图是4-可选的平面图$G$,我们证实了这一猜想。

英文摘要

Assume $G$ is a graph and $k$ is a positive integer. Let $f:V(G)\to \mathbb{N}$ be defined as $f(v)=\min\{k,d_G(v)\}$. If $G$ is $f$-choosable, then we say $G$ is degree-truncated $k$-choosable. The degree-truncated choice number of $G$ is $\operatorname{ch}^{\text{\st{d}}}(G) = \min\{k: G \text{ is degree-truncated $k$-choosable}\}$. For a family $\mathcal{G}$ of graphs, $\operatorname{ch}^{\text{\st{d}}}(\mathcal{G}) = \max\{\operatorname{ch}^{\text{\st{d}}}(G):G \in \mathcal{G}\}$. Let $\mathcal{P}$ denote the family of 3-connected non-complete planar graphs. Richter asked in 2008 whether $ch^{\text{\st{d}}}(\mathcal{P}) \le 6$. In 2025, Zhou, Zhu and Zhu answered this question in negative and proved that $8 \le ch^{\text{\st{d}}}(\mathcal{P}) \le 16$. This result was improved by Jiang, Xu, Xu, and Zhu, who proved that $9 \le ch^{\text{\st{d}}}(\mathcal{P}) \le 12$. In this paper, we further improve the result and prove that $10 \le \operatorname{ch}^{\text{\st{d}}}(\mathcal{P}) \le 11$. We conjecture that $\operatorname{ch}^{\text{\st{d}}}(\mathcal{P}) =10$, and we confirm this conjecture for those planar graphs $G \in \mathcal{P}$ for which the subgraph induced by vertices of degree at least 11 is 4-choosable.

2606.06215 2026-06-05 physics.flu-dyn cond-mat.soft

Flapping instability of elastic disks in Stokes flows

弹性圆盘在斯托克斯流中的扑动不稳定性

Yijiang Yu, Hugo Perrin, Michael D. Graham, Lorenzo Botto

AI总结 通过实验和模拟,研究低雷诺数剪切流中自由悬浮薄弹性圆盘的扑动动力学,发现超过临界流强时圆盘发生周期性弯曲扑动,并揭示其亚临界不稳定性机制。

详情
AI中文摘要

低雷诺数下的流固耦合现象可以比先前预期的更加丰富。在这里,我们研究了一个自由悬浮的薄弹性圆盘在剪切流中的动力学,其中圆盘的平面最初平行于流动平面。通过实验和模拟的结合,我们证明超过临界流强时圆盘变形,执行扑动动力学,其中圆盘相对于水平剪切平面周期性地上下弯曲。通过模拟获得的分岔图揭示了几个振荡解,包括由线性稳定性分析预测的摆动运动。扑动动力学被证明是一种亚临界不稳定性,其关键因素是圆盘的有限可伸展性。我们观察到的行为对新兴的片状颗粒(如浸没在粘性流体中的二维聚合物和二维晶体材料)的流动动力学研究具有启示意义。

英文摘要

Fluid-structure interactions at low Reynolds number can lead to a much richer phenomenology than previously expected. Here, we study the dynamics of a freely suspended, thin elastic disk in a shear flow, where the plane of the disk is initially parallel to the flow plane. Using a combination of experiments and simulations, we demonstrate that beyond a critical flow strength the disk deforms, performing flapping dynamics, in which the disk curves up and down periodically relative to the horizontal shear plane. The bifurcation diagram obtained by simulation reveals several oscillatory solutions, including a wiggling motion that is predicted by a linear stability analysis. The flapping dynamics is shown to be a subcritical instability whose key ingredient is the finite extensibility of the disk. The behavior we observe has implications for emerging investigations on the flow dynamics of sheet-like particles, such as 2D polymers and 2D crystalline materials immersed in viscous fluids.

2606.06213 2026-06-05 astro-ph.HE

Probing a new subclass of llGRB-SN transients: Insights from EP250304a and its associated supernova

探测llGRB-SN瞬变的一个新子类:来自EP250304a及其相关超新星的见解

L. Cotter, A. Martin-Carrillo, R. A. J. Eyles-Ferris, L. Izzo, D. B. Malesani, Y. Julakanti, G. Corcoran, A. Saccardi, P. G. Jonker, A. J. Levan, F. Carotenuto, P. T. O'Brien, J. H. Gillanders, J. N. D. van Dalen, M. E. Ravasio, S. Schulze, N. Sarin, F. E. Bauer, M. Fraser, J. Quirola-Vasquez, A. P. C. van Hoof, S. J. Smartt, C. Gall, A. Rest, C. T. Murphey, N. Tanvir, T. -W. Chen, S. Campana, C. Ashall, J. P. Anderson, J. A. Chacon, F. J. Cowie, V. D'Elia, L. Galbany, C. P. Gutierrez, D. H. Hartmann, P. Jakobsson, S. Kobayashi, A. H. Kong, P. Mazalli, T. E. Muller-Bravo, M. De Pasquale, L. Rhodes, A. Rossi, J. Sanchez-Sierras, J. Sollerman, A. Andersson, A. Aryan, T. de Boer, J. S. Bright, K. C. Chambers, M. Gromadzki, M. E. Huber, C. Inserra, T. Lowe, P. Minguez, G. S. Narayan, M. Nicholl, G. S. H. Paek, A. Sedgewick, K. W. Smith, J. W. Tweddle, S. Yang

AI总结 利用爱因斯坦探针(EP)发现EP250304a,结合多波段光变曲线建模,揭示其属于激波茧主导的低光度GRB-SN新子类。

Comments 21 pages, 21 figures

详情
AI中文摘要

随着爱因斯坦探针(EP)任务的到来,我们进入了伽马射线暴(GRB)研究的新时代,能够探测到以前无法探测到的微弱、低光度瞬变现象。EP250304a是由EP发现的一个事件,与位于z=0.2的宽谱线Ic型超新星(SN) SN 2025fhm成协。尽管在EP触发时未探测到伽马射线发射,但我们找到了多个波段存在与GRB-like喷流一致的相对论性外流的证据。我们对EP250304a/SN 2025fhm进行了详细的光谱和测光分析,包括使用Redback Python包进行的多波段光变曲线建模。我们发现该事件与低光度GRB-SNe (llGRB-SNe) 如GRB 060218/SN 2006aj、GRB 100316D/SN 2010bh和GRB 171205A/SN 2017iuk非常相似,所有这些事件都表现出与热激波茧一致的早期发射。这些相似性表明EP250304A/SN 2025fhm可能属于一个新兴的激波茧主导的llGRB-SN子类,代表了更广泛的引擎驱动GRB-SN爆炸连续谱中的低光度端。

英文摘要

With the advent of the Einstein Probe (EP) mission, we are entering a new era in the study of gamma-ray bursts (GRBs), enabling the detection of faint, low-luminosity transients that would previously have gone undetected. EP250304a was an event discovered by EP associated with the broad-lined type Ic supernova (SN) SN 2025fhm located at z = 0.2. Despite no gamma-ray emission being detected at the time of the EP trigger, we identify evidence for a relativistic outflow consistent with a GRB-like jet across multiple wavelengths. We present a detailed spectral and photometric analysis of EP250304a/SN 2025fhm, including multi-band light curve modelling performed with the Redback Python package. We find that this event closely resembles low-luminosity GRB-SNe (llGRB-SNe) such as GRB 060218/SN 2006aj, GRB 100316D/SN 2010bh, and GRB 171205A/SN 2017iuk, all of which exhibit early-time emission consistent with a thermal shocked cocoon. These similarities suggest that EP250304A/SN 2025fhm may belong to an emerging subclass of shocked cocoon-dominated llGRB-SNe, representing the low-luminosity end of a broader continuum of engine-driven GRB-SN explosions.

2606.06210 2026-06-05 physics.plasm-ph

A Surrogate Model for Proton Spectrum Prediction to Map Transitions in Laser-Ion Acceleration

用于激光离子加速中跃迁映射的质子谱预测代理模型

Chengqi-Zhang, Yang He, Mamat Ali Bake, Xilin-Wang, Bai-Song Xie

AI总结 提出一种物理引导的解耦双分支代理模型,通过β-VAE与多层感知机结合,高精度预测激光驱动离子加速中的连续质子能谱,并量化不确定性,成功复现TNSA到RIT/BOA的跃迁特征。

详情
AI中文摘要

我们提出了一种物理引导的解耦双分支代理模型,用于预测激光驱动离子加速中的连续质子能谱。该框架将用于光谱特征提取的β-VAE与用于标量边界强制的并行多层感知机相结合,在最大截止能量上实现了R²=0.94的预测精度,总粒子通量上R²=0.94,整个2000-bin能量分布的中位每样本光谱R²=0.985(在log₁₀空间中)。该模型通过深度集成引入不确定性量化,作为定量概率诊断工具,校准误差低于6.2%。在一维纵向框架内,该代理模型复现了与靶法向鞘层加速(TNSA)到相对论诱导透明(RIT)和爆发后燃器(BOA)机制的体积加热动力学跃迁一致的光谱特征,并通过一维粒子模拟的动力学诊断进行了验证。该方法为未来的多保真度优化建立了计算高效的基线,并为高重复率激光设施中的闭环参数控制提供了引擎。

英文摘要

We present a physics-guided, decoupled dual-branch surrogate model to predict continuous proton energy spectra from laser-driven ion acceleration. Integrating a $β$-VAE for spectral feature extraction with a parallel multi-layer perceptron for scalar boundary enforcement, the framework achieves a predictive accuracy of $R^2 = 0.94$ for the maximum cutoff energy and $R^2 = 0.94$ for the total particle flux, with a median per-sample spectral $R^2 = 0.985$ (in $\log_{10}$ space) across the full 2000-bin energy distribution. The model incorporates uncertainty quantification via deep ensembles, serving as a quantitative probabilistic diagnostic tool with calibration errors below 6.2\%. Within the 1D longitudinal framework, the surrogate reproduces spectral signatures consistent with the transition from Target Normal Sheath Acceleration (TNSA) to the volumetric heating dynamics of Relativistically Induced Transparency (RIT) and Breakout Afterburner (BOA) regimes, as validated against kinetic diagnostics from 1D particle-in-cell simulations. This approach establishes a computationally efficient baseline for future multi-fidelity optimization and provides an engine for closed-loop parameter control in high-repetition-rate laser facilities.

2606.06209 2026-06-05 gr-qc

The first decade of gravitational-wave measurements of black hole spins

黑洞自旋引力波测量的第一个十年

Sylvia Biscoveanu

AI总结 本文综述了引力波探测十年间对恒星质量黑洞自旋的测量结果,总结了不同形成通道(孤立双星演化、星团动力学形成、活动星系核盘形成、层级三体)对自旋大小和方向的预测,描述了自旋效应在引力波波形中的印记及单个事件中自旋的可测性,并回顾了当前对自旋大小、方向和有效自旋参数的人口约束及其天体物理含义。

Comments Prepared for the Galaxies special issue on "Gravitational-Wave Probes of Black Hole Spin and Binary Dynamics"

详情
AI中文摘要

在引力波首次直接探测十年后,不断增长的超过一百个确认事件的目录正揭示出关于恒星质量黑洞自旋的新见解。自旋测量长期以来被视为致密天体双星形成和演化的有前景的示踪剂,因为不同的形成通道在人口层面上预测了独特的自旋特征。在这篇综述中,我们总结了黑洞自旋的天体物理学、现象学和当前测量结果。我们首先概述了主要形成通道——孤立双星演化、星团中的动力学形成、活动星系核盘中的形成以及层级三体——对黑洞自旋大小和方向的预测。然后,我们描述了自旋效应在引力波波形上的印记以及单个事件中自旋的可测性。最后,我们回顾了当前对自旋大小、方向和有效自旋参数的人口层面约束,包括与质量和红移的相关性,并讨论了它们的天体物理含义。我们最后强调了未解决的问题和未来前景,指出改进的探测器灵敏度将如何使得对单个事件和整个双黑洞人口的自旋测量越来越精确。

英文摘要

A decade after the first direct detection of gravitational waves, the growing catalog of over one hundred confirmed events is revealing new insights into the spins of stellar-mass black holes. Spin measurements have long been heralded as a promising tracer of compact-object binary formation and evolution, as different formation channels predict unique spin signatures on a population level. In this review, we summarize the astrophysics, phenomenology, and current measurements of black hole spins. We begin with an overview of the predictions for black hole spin magnitudes and orientations from leading formation channels--isolated binary evolution, dynamical formation in clusters, formation in AGN disks, and hierarchical triples. We then describe the imprint of spin effects on the gravitational waveform and the measurability of spin in individual events. Finally, we review current population-level constraints on spin magnitudes, orientations, and effective spin parameters, including correlations with mass and redshift, and discuss their astrophysical implications. We conclude by highlighting open questions and future prospects, emphasizing how improved detector sensitivity will enable increasingly precise spin measurements for both individual events and the binary black hole population as a whole.

2606.06208 2026-06-05 math.CO

Non-trivial Intersection Problems for Multi-part Hypergraphs

多部超图的非平凡交问题

Jianfeng Hou, Caiyun Hu

AI总结 研究多部超图中排除固定顶点或坐标的极值例子的非平凡交问题,给出了对称积中非平凡t-交问题的精确值,并推广到一般积中无公共顶点的交族最大尺寸的公式。

详情
AI中文摘要

我们研究多部超图的非平凡交问题,排除了通常由固定顶点或固定坐标决定的极值例子。我们的第一个结果确定了对称积 $[n]^r$ 中非平凡 $t$-交问题在 $1\le t\le r-2$ 且所有 $n\ge2$ 时的精确值。Frankl 和 Nie 证明了对于足够大的 $n$ 的一个双候选公式,并猜想它对所有 $n\ge 2$ 成立;我们的公式表明,在 $n$ 的小范围内,猜想表达式必须通过额外的 Ahlswede--Khachatrian 球型项来扩大。 我们的第二个结果涉及一般积 $X_1\times\cdots\times X_r$ 中的交族,其中 $|X_i|=n_i$,且没有公共顶点。设 $m_0(1,n_1,\ldots,n_r)$ 表示这种族的最大尺寸。我们证明这个数等于对所有下集 $\mathcal{D}\subseteq 2^{[r]}$ 满足 $\bigcup_{X\in \mathcal{D}}X=[r]$ 且 $\mathcal{D}$ 中任意两个成员的并集不为 $[r]$ 的 $\sum_{X\in \mathcal{D}}\prod_{i\in X}(n_i-1)$ 的最大值。这个有限约化将交障碍与部分大小分离,并给出了 $r=4,5,6$ 的显式完全非对称公式。

英文摘要

We study non-trivial intersection problems for multi-part hypergraphs, excluding the usual extremal examples determined by fixed vertices or fixed coordinates. Our first result determines the exact value of the non-trivial $t$-intersection problem in the symmetric product $[n]^r$ for $1\le t\le r-2$ and all $n\ge2$. Frankl and Nie proved a two-candidate formula for sufficiently large $n$ and conjectured it for all $n\ge 2$; our formula shows that the conjectured expression must be enlarged, in small ranges of $n$, by additional Ahlswede--Khachatrian ball-type terms. Our second result concerns intersecting families in general products $X_1\times\cdots\times X_r$, where $|X_i|=n_i$, with no common vertex. Let $m_0(1,n_1,\ldots,n_r)$ denote the largest size of such a family. We show that this number is equal to the maximum of $\sum_{X\in \mathcal{D}}\prod_{i\in X}(n_i-1)$ over all downsets $\mathcal{D}\subseteq 2^{[r]}$ such that $\bigcup_{X\in \mathcal{D}}X=[r]$ and no two members of $\mathcal{D}$ have union $[r]$. This finite reduction separates the intersection obstruction from the part sizes and yields explicit fully asymmetric formulas for $r=4,5,6$.

2606.06206 2026-06-05 math.AP

Local and global properties of solutions of an elliptic equation involving exponential and gradient reaction

涉及指数和梯度反应的椭圆方程解的局部和全局性质

Marie-Françoise Bidaut-Véron, Marta Garcia-Huidobro, Laurent Véron

AI总结 研究带指数项和梯度项的椭圆方程在奇点或外部区域中解的局部与渐近行为,并证明相应解的存在性,关键依赖于参数q与2的大小关系。

Comments 42 pages

详情
AI中文摘要

我们研究了在穿孔区域$Ω\setminus\{0\}$或$R^N$($N\geq 2$)的外部区域中方程$-Δu- m|\nabla u|^q-e^{u}=0$的局部和全局性质,其中$m$是正参数,$q>1$。我们特别研究了具有孤立奇点的解的局部行为或定义在外部区域中的解的渐近行为,以及具有前述行为的解的存在性。这些行为根据$q$小于或大于$2$而发生剧烈变化。通过引入与该方程相关的各种动力系统,我们获得了许多结果。

英文摘要

We study some local and global properties of solutions of $-Δu- m\abs{\nabla u}^q-e^{u}=0$ in a punctured domain $Ω\setminus\{0\}$, or in an exterior domain of $R^N$, $N\geq 2$, where $m$ is a positive parameter and $q>1$. We study particularly the local behaviour of solutions with an isolated singularity or the asymptotic behaviour for solutions defined in an exterior domain, and also the existence of solutions with the behaviours previously described. These behaviours change drastically according $q$ is smaller or larger than $2$. Many results are obtained by introducing various dynamical systems associated to the equation.

2606.06204 2026-06-05 quant-ph

Semidefinite-programming hierarchies for classically simulable state families

经典可模拟态族的半定规划层次结构

Mengyan Li, Yanning Jia, Fenzhuo Guo, Haifeng Dong, Sujuan Qin, Fei Gao

AI总结 针对任意有限维度的经典可模拟态族,提出完整的半定规划层次结构,通过重构为确定性响应函数和秩一投影可模拟POVM的可行性问题,给出可计算的上界并匹配经典模拟。

详情
AI中文摘要

确定一个态族是否具有不可约的量子优势是量子资源理论和量子信息处理中的基本任务。这里我们研究经典可模拟态族,即那些位于两两交换族凸包内并因此具有经典解释的态族。我们发展了一个完整的半定规划(SDP)层次结构,用于刻画任意有限维度下经典可模拟态族的集合。关键步骤是将经典可模拟性重新表述为关于确定性响应函数和由秩一投影测量可模拟的辅助正算子值测度(POVM)的可行性问题。我们为秩一投影可模拟POVM建立了一个完整的SDP层次结构,并将所得刻画转移到态族,既提供了原始可行性检验,也提供了对偶仿射见证,用于证明经典可模拟性的失败。将该层次结构应用于与去极化噪声混合的态族,给出了临界经典可见性的可计算上界,并在几个对称例子中通过显式经典模拟匹配。这些结果为证明量子态族的经典可模拟性提供了一个系统的凸优化框架。

英文摘要

Identifying whether a state family admits an irreducible quantum advantage is a fundamental task in quantum resource theory and quantum information processing. Here we study classically simulable state families, namely those residing within the convex hull of pairwise commuting families and therefore admitting a classical explanation. We develop a complete semidefinite-programming (SDP) hierarchy characterizing the set of classically simulable state families in arbitrary finite dimension. The key step is to reformulate classical simulability as a feasibility problem over deterministic response functions and auxiliary positive-operator-valued measures (POVMs) simulable by rank-one projective measurements. We establish a complete SDP hierarchy for rank-one projectively simulable POVMs and transfer the resulting characterization to state families, yielding both primal feasibility tests and dual affine witnesses certifying failure of classical simulability. Applying the hierarchy to state families mixed with depolarizing noise gives computable upper bounds on the critical classical visibility, which are matched by explicit classical simulations in several symmetric examples. These results provide a systematic convex-optimization framework for certifying classical simulability of quantum state families.

2606.06202 2026-06-05 math.CO

Exact extremal constructions for the inducibility of blowup graphs

爆炸图诱导性的精确极值构造

Wanfang Chen, Xizhi Liu

AI总结 对于任意图H,证明存在常数h_*(H),使得当h≥h_*(H)且n足够大时,所有最大化H^{(h)}诱导拷贝数的n顶点图都是H的爆炸图,解决了Bollobás等人1995年提出的问题。

Comments 14pp, comments are welcome

详情
AI中文摘要

对于有限图$H$和正整数$h$,$H$的$h$-爆炸图$H^{(h)}$是通过将$H$的每个顶点替换为一个大小为$h$的集合,并将每条边替换为对应集合之间的完全二部图得到的图。我们证明,对于每个$H$,存在常数$h_*(H)$,使得当$h\ge h_*(H)$且$n$足够大时,每个最大化$H^{(h)}$诱导拷贝数的$n$顶点图都是$H$的爆炸图。这改进了Hatami、Hirst和Norine的渐近结果,并解决了Bollobás、Egawa、Harris和Jin在1995年提出的问题。

英文摘要

For a finite graph $H$ and a positive integer $h$, the $h$-blowup $H^{(h)}$ of $H$ is the graph obtained by replacing each vertex of $H$ by a set of size $h$ and each edge by a complete bipartite graph between the corresponding sets. We prove that, for every $H$, there exists a constant $h_*(H)$ such that whenever $h\ge h_*(H)$ and $n$ is sufficiently large, every $n$-vertex graph maximizing the number of induced copies of $H^{(h)}$ is a blowup of $H$. This refines the asymptotic result of Hatami, Hirst and Norine and settles the question posed by Bollobás, Egawa, Harris and Jin in 1995.

2606.06198 2026-06-05 cs.NE astro-ph.CO astro-ph.GA astro-ph.IM

Hub-Aware Hybrid Search: Accelerating the Locally Aligned Ant Technique

Hub感知混合搜索:加速局部对齐蚂蚁技术

Simone Vilardi, Reynier Peletier, Felipe Contreras, Kerstin Bunte

AI总结 针对局部对齐蚂蚁技术(LAAT)在检测高维点云中流形结构时受密集中心(hub)影响导致计算开销大的问题,提出一种两阶段方法:快速预处理定位中心并用似然模型替换,再通过混合似然-信息素策略引导蚂蚁高效穿越密集区域,提升检测效率和鲁棒性。

Comments 6 pages, 4 figures, published in the ESANN 2026 proceedings

详情
Journal ref
ESANN 2026, European Symposium on Artificial Neural Networks, Computational Intelligence and Machine Learning, Bruges, Belgium, April 22-24, 2026
AI中文摘要

在噪声和高维点云中寻找流形结构是一个具有挑战性但重要的问题。在天文观测巡天和模拟数据中,检测纤维状结构、流(1维)、壁(2维)和团簇(3维)有助于更深入地理解宇宙的演化。局部对齐蚂蚁技术(LAAT)使用受生物启发的智能体来高效恢复微弱和多维结构。然而,非常密集的中心(例如节点或球状星团)主导了蚂蚁的活动,造成了不必要的计算开销。在本文中,我们提出一个两阶段解决方案。首先,一个快速的预处理步骤定位中心并用定制的似然模型替换它们。随后,一种混合似然-信息素策略引导蚂蚁高效地穿越密集区域。我们通过合成数据和大型宇宙网天文N体模拟展示了LAAT检测效率和鲁棒性的提升。

英文摘要

Finding manifold structures in noisy and high-dimensional point clouds is a challenging but important problem. In astronomical observation survey and simulation data the detection of filaments, streams (1D), walls (2D) and clusters (3D) gives rise to deeper understanding of the evolution of our universe. The Locally Aligned Ant Technique (LAAT) uses biologically inspired agents to efficiently recover faint and multidimensional structures. However, very dense hubs (e.g. nodes or globular clusters) dominate the ants' activity, creating unnecessary computational overheads. In this paper we propose a two-stage solution. First a fast preprocessing step locates the hubs and replaces them with a tailored likelihood model. Subsequently, a mixed likelihood-pheromone strategy guides the ants to efficiently bridge the dense regions. We demonstrate improvements in detection efficiency and robustness of LAAT with synthetic and a large-scale astronomical N-body simulation of the cosmic web.

2606.06195 2026-06-05 physics.plasm-ph

Wave drag in moving plasmas: recent developments and prospects

运动等离子体中的波拖曳:最新进展与展望

Renaud Gueroult, Aymeric Braud, Julien Langlois

AI总结 本文回顾了运动效应对等离子体波影响的现有模型,识别了在现实配置中量化这些模型面临的基本挑战,并讨论了可能的解决方案。

Comments 14 pages, 5 figures

详情
AI中文摘要

波在介质中的传播取决于该介质相对于观察者是静止还是运动。运动可能导致波的轨迹、偏振或横向结构的改变。尽管这些效应在各向同性电介质中已有充分记录,但在等离子体中仍 largely 未被探索和考虑,尽管简单模型表明在某些条件下它们可能很大,并且最近的实验观察也支持这一点。这里我们首先回顾了运动效应对等离子体波的现有模型,然后识别了在现实配置中使用这些模型量化运动效应所面临的一些基本挑战,最后讨论了可能的变通方法。

英文摘要

Wave propagation in a medium differs depending on whether this medium is at rest or moving with respect to an observer. Motion can notably lead to modifications of the wave trajectory, of its polarization, or of its transverse structure. Although these effects are well documented in isotropic dielectrics, they remain largely unexplored and unaccounted for in plasmas, despite the fact that simple models suggest they could in fact be large under certain conditions, as well as recent experimental observations. Here we first review existing models for motion effects on plasma waves, then identify a number of basic challenges that lie in the way of using these models to quantify motion effects in realistic configurations, and finally discuss possible workarounds.

2606.06193 2026-06-05 math.PR math.OC

Peng's Maximum Principle for McKean-Vlasov Stochastic Differential Equations with Common Noise

具有共同噪声的McKean-Vlasov随机微分方程的彭氏最大值原理

Johan Benedikt Spille, Wilhelm Stannat

AI总结 针对状态依赖于条件分布的McKean-Vlasov随机微分方程,推导了无需控制域凸性假设的彭型随机最大值原理,并引入第三个伴随状态以对偶化成本泛函泰勒展开中的所有二阶Lions导数。

详情
AI中文摘要

我们研究了具有共同噪声的McKean-Vlasov随机微分方程(SDE)的随机最优控制问题,其中动力学依赖于状态的条件分布。我们在不施加控制域凸性假设的情况下,推导了彭型随机最大值原理。与标准McKean-Vlasov情形相比,共同噪声情形的最大值原理包含第三个伴随状态,这是对偶化成本泛函泰勒展开中所有二阶Lions导数所必需的。额外的伴随状态由条件McKean-Vlasov倒向SDE给出。所有三个伴随状态共同允许在二阶展开中所有贡献的完全线性化,包括第一个变分过程的条件独立副本之间的相互作用。作为分析的一部分,我们还证明了条件McKean-Vlasov倒向SDE的一般适定性结果。

英文摘要

We study a stochastic optimal control problem for McKean-Vlasov stochastic differential equations (SDEs) with common noise, where the dynamics depend on the conditional law of the state. We derive a stochastic maximum principle of Peng type without imposing convexity assumptions on the control domain. In comparison to the standard McKean-Vlasov case, the maximum principle for the common noise case contains a third adjoint state, which is needed to dualize all second-order Lions derivatives in the Taylor expansion of the cost functional. The additional adjoint state is given by a conditional McKean-Vlasov backward SDE. All three adjoint states together allow for a complete linearization of all contributions in the second-order expansion, including interactions between conditionally independent copies of the first variational process. As part of our analysis, we also prove a general well-posedness result for conditional McKean-Vlasov backward SDEs.

2606.06192 2026-06-05 math.CO cs.DM

A unified abstract regularity lemma

统一抽象正则引理

Gaia Carenini, Leonardo Franchi

AI总结 本文证明了一个统一抽象正则引理,直接推导出Szemerédi图正则引理、Green算术正则引理和布尔函数正则引理。

详情
AI中文摘要

这篇短注的目标是证明一个统一抽象正则引理,该引理将Szemerédi图正则引理、Green算术正则引理和布尔函数正则引理作为直接推论。

英文摘要

The goal of this short note is to prove a unified abstract regularity lemma which recovers Szemerédi's graph regularity lemma, Green's arithmetic regularity lemma, and a regularity lemma for Boolean functions as direct corollaries.

2606.06191 2026-06-05 physics.flu-dyn

Deep reinforcement learning with spatial and temporal awareness for active boundary control of buoyancy-driven convection

具有时空感知能力的深度强化学习用于浮力驱动对流的主动边界控制

Giorgio Maria Cavallazzi, Miguel Pérez Cuadrado, Alfredo Pinelli

AI总结 针对深度强化学习在热对流控制中产生的退化驱动问题,提出结合卷积策略网络、GRU记忆、离策略训练和动作平滑约束的框架,成功实现细胞合并并降低努塞尔数,并在双扩散对流中自适应发现行波驱动。

详情
AI中文摘要

应用于热对流控制的深度强化学习(DRL)持续产生 extit{退化驱动}:壁温策略的输出饱和、伪随机或空间不连贯。两个复合缺陷是原因:丢弃空间流动结构的多层感知器策略,以及无法区分自诱导流动变化与背景演化的无记忆策略。两者共同阻止了物理上有意义的控制律的发现,即使细胞合并(对流卷合并为更少、更大的结构)可以降低$\mathrm{Nu}$,且可通过边界驱动实现。本框架通过四个有针对性的设计选择解决了这两个原因:卷积策略网络、门控循环单元(GRU)记忆、离策略训练(TD3/MADDPG)和动作平滑约束。一个系统的$2 imes2$因子设计隔离了每个组件的贡献。在$\mathrm{Ra}=10{,}000$的瑞利-贝纳德对流中,所有四种配置在350个回合内实现了细胞合并并将$\mathrm{Nu}$降低至低至$1.83$(比未控制基线低$26\%$),无需先前工作所需的全场数据增强。关键的是,即使是单智能体配置也能实现合并,表明一旦策略架构足够表达,多智能体公式并非先决条件。应用于盐指 regime 的双扩散对流时,该框架自发发现了一种行波驱动,其相速度适应流动的演化混合状态,将传热提高了$19.1\%$,并将盐度方差降低了$21.0\%$。

英文摘要

Deep reinforcement learning (DRL) applied to thermal convection control consistently produces \textit{degenerate actuation}: wall-temperature policies whose outputs are saturated, pseudo-random, or spatially incoherent. Two compounding deficiencies are responsible: multilayer-perceptron policies that discard spatial flow structure, and memoryless policies that cannot distinguish self-induced flow changes from background evolution. Together they prevent the discovery of physically meaningful control laws even when cell coalescence (the merging of convection rolls into fewer, larger structures), which would reduce $\mathrm{Nu}$, is accessible to boundary actuation. The present framework addresses both causes through four targeted design choices: convolutional policy networks, Gated Recurrent Unit (GRU) memory, off-policy training (TD3/MADDPG), and action-smoothness constraints. A systematic $2\times2$ factorial design isolates the contribution of each component. On Rayleigh--Bénard convection at $\mathrm{Ra}=10{,}000$, all four configurations achieve cell coalescence and reduce $\mathrm{Nu}$ to as low as $1.83$ ($26\%$ below the uncontrolled baseline) in 350 episodes, without the full-field data augmentation required by prior work. Crucially, coalescence is achieved even by the single-agent configuration, demonstrating that the multi-agent formulation is not a prerequisite once the policy architecture is sufficiently expressive. Applied to double-diffusive convection in the salt-finger regime, the framework spontaneously discovers a travelling-wave actuation whose phase speed adapts to the evolving mixing state of the flow, enhancing heat transfer by $19.1\%$ and reducing salinity variance by $21.0\%$.

2606.06190 2026-06-05 q-fin.ST

Multi-Scale Markov Switching GARCH

多尺度马尔可夫转换GARCH

Jayesh Chaudhary

AI总结 针对金融波动非平稳性,提出三重时间框架的MS-GARCH模型,通过独立估计日、4小时、小时三个时间尺度的AR(1)-MS-GARCH并利用Filardo时变转移概率和复合压力指标,构建27状态跨尺度概率张量,在EUR/USD数据上优于传统GARCH的波动率预测。

详情
AI中文摘要

金融波动表现出显著的非平稳性,使得单机制模型不足以描述变化的市场条件。本文提出一个三重时间框架的马尔可夫转换GARCH(MS-GARCH)框架,用于检测欧元/美元在日、四小时和小时间隔上的波动率机制。估计了三个独立的AR(1)-MS-GARCH模型以捕捉宏观、中观和微观机制动态,同时在较短时间尺度上通过复合压力指标引入Filardo风格的时变转移概率(TVTP)。得到的机制概率通过外积构造组合成一个27状态跨尺度概率张量。使用2015-2025年的欧元/美元数据,该框架产生了统计上显著的平静、动荡和危机机制,并且相对于传统GARCH基准实现了更优的样本外波动率预测性能。结果表明,波动率动态在多个时间尺度上包含有意义的结构,并且分别对这些尺度进行建模比单一时间尺度方法能提供更具信息性的市场条件表示。

英文摘要

Financial volatility exhibits substantial non-stationarity, making single-regime models inadequate for characterising changing market conditions. This paper proposes a triple-timeframe Markov-Switching GARCH (MS-GARCH) framework for volatility regime detection in EUR/USD across daily, four-hour, and hourly horizons. Three independent AR(1)-MS-GARCH models are estimated to capture macro, meso, and micro regime dynamics, while Filardo-style time-varying transition probabilities (TVTP) are incorporated at the shorter horizons through composite stress indicators. The resulting regime probabilities are combined through an outer-product construction into a 27-state cross-scale probability tensor. Using EUR/USD data from 2015-2025, the framework produces statistically distinct Calm, Turbulent, and Crisis regimes and achieves superior out-of-sample volatility forecasting performance relative to a conventional GARCH benchmark. The results suggest that volatility dynamics contain meaningful structure across multiple timescales and that modelling these scales separately provides a more informative representation of market conditions than a single-timescale approach.

2606.06189 2026-06-05 cs.MA

A Swarm Approach to Public Transit Using On-demand Routing in a Slime-Mold-Inspired Framework

一种基于黏菌启发框架的按需路由公交集群方法

Lindsay Burke, Maxfield Comstock, Jason Graham, Ruth Malenda, Simon Garnier, Petras Swissler

AI总结 提出一种基于黏菌启发路由算法的分布式动态按需公交系统,通过持续合作竞标实现乘客分配和动态换乘,在郊区、城市和半乡村场景中分别提升乘客送达率28%、49%和101%,并减少步行时间超过75%。

详情
AI中文摘要

需求响应式公交(DRT)是传统固定路线大众运输网络的灵活替代方案。尽管DRT在低密度社区中表现良好,但高运营成本和低可靠性是常见问题。我们提出,通过从集中式手动调度方案转向分布式系统,该系统能够使用黏菌启发路由算法动态调度多辆车辆以最大化网络效率,可以缓解这些问题。我们还引入了动态换乘方法以进一步优化公交网络效率。所有乘客分配和动态换乘均通过公交车的持续合作竞标过程处理。在本文中,我们展示了在郊区、城市和半乡村场景中,使用从OpenStreetMap提取的地图网络进行的集群驱动公交网络的模拟结果。我们表明,与固定网络方法相比,我们的方法分别将乘客送达率提高了28%、49%和101%,并且在所有情况下步行时间减少了超过75%。

英文摘要

Demand-responsive transit (DRT) is a flexible alternative to traditional, fixed-route mass-transit networks. Although DRT can function well in low-density communities, high operating costs and low reliability are common issues. We propose that these issues can be mitigated by moving from a centralized, manually-scheduled scheme to a distributed system capable of dynamically routing multiple vehicles using a slime-mold-inspired routing algorithm to maximize network effectiveness. We additionally introduce the method of dynamic transfers to further optimize transit network efficiency. All passenger allocation and dynamic transfers are handled via a continual cooperative bidding process by the buses. In this paper, we present simulated results for a swarm-driven transit network in suburban, urban, and semi-rural scenarios, using map networks pulled from OpenStreetMap. We show that our approach increases passenger delivery rates relative to a fixed-network approach by 28%, 49%, and 101%, respectively, and results in over 75% reduction in walking time in all cases.

2606.06187 2026-06-05 math.PR

How to Study Reflected Brownian Motion in a Quadrant via Kernel Functional Equations? A short survey

如何通过核函数方程研究象限中的反射布朗运动?简短综述

Sandro Franceschi

AI总结 本文综述了通过核函数方程研究象限中半鞅反射布朗运动的方法,涵盖非退化和退化情形,重点讨论了不变测度、格林函数、调和函数及其拉普拉斯变换的显式表示和渐近分析。

Comments 51 pages

详情
AI中文摘要

我们综述了一系列研究象限中半鞅反射布朗运动的文献,涵盖了非退化和退化情形。强调两种主要情况:存在不变测度的常返情形,以及核心对象为格林函数(势测度)的瞬变情形。这些测度通常来自柯尔莫哥洛夫向前方程。对于瞬变或杀死模型,人们还关心过程的马丁边界,进而关心所有满足柯尔莫哥洛夫向后方程的正调和函数。根据模型的几何和参数,这些调和函数通常具有吸收、逃逸或漂移至无穷的概率解释。所有这些测度和函数都通过其拉普拉斯变换所满足的核函数方程进行研究。回顾了求解这些方程的几种方法,每种方法导致不同类型的结果。遵循Fayolle、Iasnogorodski和Malyshev为四分之一平面随机游走发展的解析方法,一个关键的初步步骤是将相关拉普拉斯变换解析延拓到由核的零点集定义的复代数曲线上。然后,卡尔曼边值问题技术为拉普拉斯变换提供了显式的围道积分表示。在特殊参数区域,图特的恒等方法提供了无积分公式,并根据代数-微分复杂度对变换进行了清晰分类。结合鞍点法对核代数曲线进行奇点分析,产生了精确的二维渐近行为。最后,在退化情形中,补偿方法提供了一种替代的构造性方法,通过显式迭代修正将密度构建为无穷级数。

英文摘要

We survey a line of works studying semimartingale reflected Brownian motion in a quadrant, covering both the non-degenerate and degenerate settings. Two main situations are emphasized: the recurrent case, where an invariant measure exists, and the transient case, where the central objects are Green's functions (potential measures). These measures typically arise from Kolmogorov forward equations. For transient or killed models one is also interested in the Martin boundary of the process and, consequently, in all positive harmonic functions, which satisfy Kolmogorov backward equations. Depending on the geometry and parameters of the model, these harmonic functions often admit probabilistic interpretations in terms of absorption, escape, or drift to infinity. All these measures and functions are studied through kernel functional equations satisfied by their Laplace transforms. Several ways of solving these equations are reviewed, each leading to different types of results. Following the analytic approach developed for quarter-plane random walks by Fayolle, Iasnogorodski and Malyshev, a key preliminary step is the analytic continuation of the relevant Laplace transforms onto the complex algebraic curve defined by the zero set of the kernel. Carleman boundary value problem techniques then yield explicit contour-integral representations for the Laplace transforms. In special parameter regimes, Tutte's invariant method provides integral-free formulas and a sharp classification of the transforms according to their algebraic-differential complexity. Singularity analysis combined with saddle-point methods carried out on the kernel algebraic curve, produces precise two-dimensional asymptotics. Finally, in the degenerate setting, the compensation approach provides an alternative constructive method, allowing one to build the densities as an infinite series through explicit iterative corrections.

2606.06185 2026-06-05 cond-mat.mes-hall

Non-adiabatic Ehrenfest dynamics with norm-conserving and ultra-soft pseudo-potentials with nuclear velocity corrections on the atomic orbitals within the Projector Augmented Wave Method framework

投影增强波方法框架下包含核速度修正的原子轨道上的模守恒和超软赝势的非绝热埃伦费斯特动力学

Paolo Fachin, Francesco Macheda, Paolo Barone, Francesco Mauri

AI总结 推导了包含核速度依赖相位(电子平移因子)的原子轨道基第一性原理埃伦费斯特分子动力学,用于描述非绝热过程,并消除了忽略核速度相位导致的虚假非绝热耦合。

详情
AI中文摘要

我们推导了第一性原理埃伦费斯特分子动力学,描述了包含原子轨道基上核速度依赖相位(也称为电子平移因子)的非绝热过程。当核被动态处理时,这些相位会影响由局域轨道构建的有效哈密顿量。在这项工作中,我们关注第一性原理赝势哈密顿量中的效应,包括模守恒和超软情况,这些都是在投影增强波(PAW)方法框架内推导的。在势的非局域部分出现了依赖于核速度的Peierls-like相位,而在超软赝势情况下出现了额外的核速度和加速度依赖修正。使用包含速度的原子轨道基能够实现非绝热埃伦费斯特分子动力学的伽利略不变描述,消除了由于忽略原子轨道中核速度相位而产生的虚假非绝热耦合。

英文摘要

We derive the first-principles Ehrenfest molecular dynamics describing non-adiabatic processes with the inclusion of the nuclear-velocity-dependent phases (also known as electron-translation factors) on the atomic-orbital basis. These phases, appearing when nuclei are treated dynamically, affect effective Hamiltonians constructed from localised orbitals. In this work, we focus on the effects in the first-principles pseudo-potential Hamiltonian, both for the norm-conserving and ultra-soft cases, derived within the Projector-Augmented-Wave (PAW) method framework. Peierls-like phases depending on the nuclear velocities appear in the non-local part of the potential, while additional nuclear velocity and acceleration-dependent corrections appear in the ultra-soft pseudo-potential case. The use of velocity-including atomic orbital basis enables a Galilean-invariant description of the non-adiabatic Ehrenfest molecular dynamics, removing spurious non-adiabatic couplings that arise from neglecting the nuclear velocity phases in the atomic orbitals.

2606.06184 2026-06-05 cond-mat.stat-mech cond-mat.mes-hall

The mesoscopic foundations of non equilibrium thermodynamics and the arrow of time in the Dual Model of Liquids

非平衡热力学的介观基础与液体对偶模型中的时间箭头

Fabio Peluso

AI总结 本文通过液体对偶模型中类固体分子团簇与晶格激发之间的相互作用,建立了正常液体宏观行为与介观物理过程的联系,并揭示了介观尺度上的时间箭头。

Comments 78 pages including 11 figures and 215 references items

详情
AI中文摘要

本手稿有两个目标。第一个目标是展示液体对偶模型中类固体分子聚集体与晶格激发之间的相互作用适合表示正常液体在宏观尺度上的行为与表征这些系统在介观尺度上的物理过程之间的联系。第二个目标是展示这种对偶性允许在液体的介观尺度上识别时间箭头。弹性能量量子与分子团簇的相互作用引入了一个优先方向,这在时间依赖和耗散的宏观过程中是相关的,尽管这种相互作用在时间上仍然是可逆的。

英文摘要

This manuscripts has two goals. The first goal is to show that the interaction in the Dual Model of Liquids between the solidlike molecule aggregates and the lattice excitations is appropriate to represent the link between the behaviour at macroscopic scale of normal liquids and the physical processes characterizing those systems at mesoscopic scale. The second goal is to show that the duality allows identifying a time arrow on the mesoscopic scale in liquids. The interaction of quanta of elastic energy with the molecular clusters introduces a privileged direction, which is relevant in time dependent and dissipative macroscopic processes, although the interaction remains temporally reversible

2606.06182 2026-06-05 math.FA

Product of Volterra-Type Integral and Composition Operators on Quaternionic Fock Spaces

四元数Fock空间上Volterra型积分算子与复合算子的乘积

Zhaopeng Lin, Yufeng Lu, Chao Zu

AI总结 研究四元数Fock空间上Volterra型积分算子与复合算子的乘积,通过Berezin型测试量刻画了其有界性和紧性,并利用矩阵符号的特征值映射给出了等价条件。

Comments 43 pages; Keywords: Quaternionic Fock space, slice regular function, Volterra-type operator, composition operator

详情
AI中文摘要

我们刻画了在四元数Fock空间之间作用的Volterra型积分算子与复合算子的乘积,覆盖全部范围 \(0<p,q<\infty\),允许一般的切片正则复合符号,无需任何切片保持假设。准则用Berezin型测试量表述。利用\(\star\)-乘积的固定切片矩阵实现,我们通过矩阵函数演算表达切片复合,并将测试量与矩阵符号的特征值映射相关的复Berezin型估计联系起来。我们还表明,自然仿射限制施加在这些特征值函数上,而不是复合符号本身。

英文摘要

We characterize products of Volterra-type integral operators and composition operators acting between quaternionic Fock spaces for the full range \(0<p,q<\infty\), allowing general slice regular composition symbols without any slice-preserving assumption. The criteria are formulated in terms of a Berezin-type testing quantity. Using a fixed-slice matrix realization of the \(\star\)-product, we express slice composition through a matrix functional calculus and relate the testing quantity to complex Berezin-type estimates associated with the eigenvalue maps of the matrix symbol. We also show that the natural affine restrictions are imposed on these eigenvalue functions rather than on the composition symbol itself.