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2605.00189 2026-05-04 math.AP

Local Asymptotic Patterns for Viscous Approximations of Conservation Laws

粘性近似守恒律的局部渐进行为

Alberto Bressan, Laura Caravenna, Wen Shen

AI总结 研究粘性消失近似在激波附近的行为,通过局部坐标缩放获得极限解,揭示近似方程的永恒解特性。

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AI中文摘要

研究双曲守恒律的解在激波附近通过粘性消失近似的行为,通过局部坐标缩放获得极限解,揭示近似方程的永恒解特性。

英文摘要

Solutions to hyperbolic conservation laws can be approximated in many different ways: by vanishing viscosity, relaxations, discrete or semi-discrete numerical schemes, approximation with a nonlocal flux, etc$\ldots$ For some of these methods, general ${\bf L}^1$ convergence results are available. Aim of this paper is to understand the local behavior of these approximations, in a neighborhood of point where the hyperbolic solution has a singularity. Specifically: a point along a shock, or where two shocks interact, or where a new shock is formed. Given a sequence of $ε$-approximate solutions, a general expectation is that, by a suitable local rescaling of coordinates, as $ε\to 0$ a well defined limit is obtained. This corresponds to a specific ``eternal solution" (globally defined both in space and in time) to the approximating equation. Precise results this direction are here given, in the case of vanishing viscosity.

2605.00188 2026-05-04 cond-mat.soft

Insights into the electrorheological and electrohydrodynamic regimes in electrically driven emulsion

对电控乳液中电弹性与电液动力学 regime 的见解

Majid Bahraminasr, Anand Yethiraj

AI总结 研究通过电弹性成像技术揭示了电控乳液在高频和低频下的不同行为,发现其在高频下呈现电弹性特性,低频下呈现电液动力学特性,并通过微流体学方法验证了其尺度无关性。

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AI中文摘要

最近,我们报告了电弹性成像(ERI)技术(Bahraminasr 等,2026),发现油-in-油乳液的频率依赖性电场会产生两种不同的 regime:高频的电弹性(ER)regime 和低频的电液动力学(EHD)regime。在本工作中,我们识别出一个现象模型,将 ER regime 的结果拟合到经典屈服应力流体,并发现通过重新标定后可以坍缩到主曲线上,与屈服应力近似随 $E^2$ 增长一致。宏观小振幅振荡剪切(SAOS)流变学与被动微流体学结合差分动态显微镜(DDM)进行比较,结果一致表明 ER 行为的尺度无关性,并表明不同于稳态剪切,SAOS 测量不会重构这些样品并探测其基础材料性质。最后,在 EHD regime 中同时存在稳态剪切和电场时,乳液形成由富油滴和贫油滴区域交替组成的带状结构。我们探讨了这些带的位置的递归和发散:它们在施加电场几秒内出现,并在电场关闭后迅速衰减。使用 Jensen-Shannon 散度衡量径向强度剖面之间的差异,我们显示驱动结构在时间尺度为 $1~s$ 的时间内失去记忆,这与 EHD 对流滚的时标一致。对于更长的电场关闭间隔,连续的带状事件在统计上变得独立。

英文摘要

Recently, we reported the electrorheoimaging (ERI) technique (Bahraminasr et al, 2026), and found that frequency-dependent electric field of an oil-in-oil emulsion yields two distinct regimes: a high-frequency dipolar, electrorheological (ER) regime and a low-frequency electrohydrodynamic (EHD) regime. In this work, we identify a phenomenological model to fit the results in the ER regime to a classic yield-stress fluid, and find collapse onto a master curve upon rescaling, consistent with a yield stress that grows approximately as $E^2$. Macroscopic small-amplitude oscillatory shear (SAOS) rheology is compared with passive microrheology employing differential dynamic microscopy (DDM), with the close agreement implying scale independence of the ER behaviour, and indicating that, unlike steady shear, SAOS measurements do not restructure these samples and probe underlying material properties. Finally, under the presence of both steady shear and electric fields in the EHD regime, the emulsion forms banded structures composed of alternating droplet-rich and droplet-depleted regions. We explore recurrence and divergence in the location of these bands: they emerge within seconds of field application and decay rapidly after the field is switched off. Using the Jensen--Shannon divergence between radial intensity profiles, we show that the driven structure loses memory on timescales of order $1~s$ commensurate with the timescale of the EHD convection roll. For much longer field-off intervals successive banding events become statistically independent.

2605.00187 2026-05-04 cs.NI

A Multi-Perspective Study of the Internet Shutdown in Iran

伊朗互联网断网的多视角研究

Ali Sadeghi Jahromi, Jason Jaskolka

AI总结 本文通过多维度方法分析伊朗2022和2026年互联网断网事件,揭示其通过集中边界转发平面null路由实现,BGP公告稳定,且伊朗从2019年部分BGP撤回转向2022年纯null路由。

Comments 7 pages, 1 figure

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AI中文摘要

伊朗在2026年1月和3月进行了两次全国性互联网断网,后者在撰写时仍持续进行,是记录中最长的伊朗中断。通过结合被动Censys扫描数据、五个观测点的主动TCP可达性探测以及2019至2026年33个RIPE RIS快照的BGP分析,我们显示2022和2026次断网是通过集中边界转发平面的null路由实现,而BGP公告保持稳定,且伊朗从2019年的部分BGP撤回转向2022年的纯null路由。这种控制平面和转发平面的解耦阻止了基于BGP的断网监控器检测到断网。对4571个BGP可见的伊朗前缀的主动探测显示,所有观测点中96.5至97.4%均被null路由,表明存在集中协调机制。被动扫描分析显示,断网事件之间可见主机数量增加3.7倍,这是由于测量伪影而非恢复所致,同时存在两个结构性豁免:学术网络在部分恢复期间可见主机比例从1.4%上升至66.6%,而ArvanCloud CDN保持99.7%的可见性,而其他主要运营商则下降至少77%。

英文摘要

Iran conducted two nationwide Internet shutdowns in January and March 2026, the latter ongoing at the time of writing and the longest documented Iranian disruption. Using a three-plane methodology combining passive Censys scan data, active TCP reachability probing from five vantage points, and BGP analysis across 33 RIPE RIS snapshots from 2019 to 2026, we show that the 2022 and 2026 shutdowns are enforced via forwarding-plane null-routing at a centralized border while BGP announcements remain stable, and that Iran shifted from partial BGP withdrawal in 2019 to pure null-routing by 2022. This control- and forwarding-plane decoupling prevents BGP-based outage monitors from detecting shutdowns. Active probing of 4,571 BGP-visible Iranian prefixes shows that 96.5 to 97.4% are null-routed across all vantage points, indicating a centrally coordinated mechanism. Passive scan analysis reveals a 3.7 times increase in visible hosts between shutdown events due to measurement artifacts rather than recovery, along with two structural exemptions: academic networks rise from 1.4 to 66.6% of visible hosts during partial recovery, and ArvanCloud CDN retains 99.7% visibility while other major operators drop by at least 77%.

2605.00186 2026-05-04 math.DS

Topological Prevalence of Finite Type Interval Translation Maps

有限类型区间翻译映射的拓扑普遍性

Kostiantyn Drach, Leon Staresinic, Sebastian van Strien

AI总结 本文研究了有限类型区间翻译映射的拓扑性质,证明对于每个r≥2,有限类型映射在所有可能的区间翻译映射中构成开密集集,验证了Boshernitzan和Kornfeld的长期猜想。

Comments arXiv admin note: substantial text overlap with arXiv:2411.14312

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AI中文摘要

区间翻译映射(ITM)是在区间I上定义的分段平移映射,其子区间允许重叠,不同于经典区间交换变换(IET)。有限类型ITM的吸引子是有限个区间的并集,在此不变集上T是双射的,行为类似IET。本文证明对于每个r≥2,有限类型ITM在所有可能的ITM中构成开密集集,验证了Boshernitzan和Kornfeld的长期猜想。

英文摘要

An interval translation map (ITM) is a map $T \colon I \to I$ defined as a piecewise translation on a finite partition of an interval $I$ into $r \ge 2$ subintervals. Unlike classical interval exchange transformations (IETs), the images of these subintervals are allowed to overlap, making ITMs a natural generalisation of IETs. An ITM $T$ is said to be \textit{of finite type} if its attractor $\bigcap_{n\ge 0} T^n(I)$ is a finite union of intervals; in this case, restricted to this invariant set, $T$ is bijective and hence behaves like an IET. Otherwise, $T$ is of infinite type. In this paper, for every $r \ge 2$, we prove that the set of finite type ITMs contains an open and dense subset in the space of all possible ITMs on $r$ subintervals. This confirms a topological version of a long-standing conjecture due to Boshernitzan and Kornfeld.

2605.00183 2026-05-04 cs.CR

I can't recognize (yet): Delayed Rendering to Defeat Visual Phishing Detectors

我尚无法识别(目前):延迟渲染以对抗视觉钓鱼检测器

Ying Yuan, Cristiano Alex Rado, Giovanni Apruzzese, Mauro Conti, Luigi Vincenzo Mancini

AI总结 研究指出现有视觉钓鱼检测器易受延迟渲染攻击影响,通过延迟关键元素渲染可误导检测系统,导致误判,提出浏览器扩展作为缓解方案。

Comments Accepted to IEEE EuroS&P'26

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AI中文摘要

钓鱼网页持续污染网络。已有大量对策,最先进的技术利用机器学习方法通过检查视觉表示推断网页是否无害。然而,尽管这些检测方法已证明有效,此类防御措施却因设计缺陷易受一种微妙但低成本的基于时间的攻击。这种疏忽质疑了这些防御在现实中的可靠性。首先,我们展示时间-based逃避攻击未被先前工作考虑。然后,我们揭示这些检测器的内在漏洞:通过延迟网页元素渲染可绕过。实际上,这些检测器必须计算目标网页与已知合法网页的视觉相似性。这需要在相似性计算前对目标网页进行“快照”。攻击者可以故意延迟关键元素(如logo)的渲染,使其在快照后完全显示。这种简单策略误导视觉相似性模块,使系统错误地将钓鱼页面分类为无害。我们实证表明,最先进的检测器可通过简单技术(如窗帘效应)完全被击败(检测率从100%降至0%)。我们还进行了用户研究,评估这些攻击对真实人类的有效性,并发现终端用户无法可靠识别我们的“扰动”(p<.05)。最后,我们提出缓解措施,包括一个无需调用远程服务的浏览器扩展,以警告用户可能已进入钓鱼网页。

英文摘要

Phishing webpages are continuously polluting the Web. Plenty of countermeasures have been proposed and the most advanced techniques leverage machine-learning methods that infer whether a webpage is benign or not by inspecting its visual representation. Yet, despite the demonstrated effectiveness of such detection methods, this class of defenses is, by design, susceptible to a kind of subtle-but-cheap timing-based attacks which -- worryingly, and perhaps surprisingly -- have never been investigated so far. Such an oversight questions the overall reliability of these defenses in the wild. First, we show that timing-based evasion attacks have not been accounted for by prior work on visual phishing websites detectors. Then, we elucidate the intrinsic vulnerability of these detectors: they can be bypassed by delaying the rendering of webpage elements. Practically, these detectors must compute the visual similarity between a target webpage and a known legitimate one. This requires taking a "snapshot" of the target webpage before the similarity computation. Attackers can deliberately delay the rendering of key elements, such as the logo, so that these elements appear fully only after the snapshot has been taken. This simple tactic misleads the visual-similarity module, leading the system to incorrectly classify the phishing page as benign. We empirically show that state-of-the-art detectors can be completely defeated (detection rate dropping from 100% to 0%) by employing easy-to-apply problem-space techniques such as curtain effects. We also carry out a user study, evaluating the effectiveness of these attacks against real humans, and find that end users are unable to reliably identify our "perturbations" (p<.05). Finally, we propose mitigations, including a browser-extension that, without making any call to remote services, warns users that they may have landed on a phishing webpage.

2605.00181 2026-05-04 hep-ph

Extracting production fractions of $b$ hadrons from exclusive semi-leptonic decays

从排斥半轻子衰变中提取$b$强子的产率

Carolina Bolognani, Martin Jung, Méril Reboud, K. Keri Vos

AI总结 本文提出通过测量排斥半轻子衰变$\bar B_{(s)} \to D_{(s)}^{(*)} \ell \barν$的比率,独立获取$b$强子产率比,以减少实验和理论不确定性,提高测量精度。

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AI中文摘要

$b$强子产率比是许多LHC分析中的主要不确定性来源,特别是在涉及$B_s$介子的测量中。目前用于$f_s/f_d$的值基于强子和半包容半轻子衰变的组合,部分依赖于难以量化的底层衰变假设。本文提出一种独立的方法,通过测量排斥半轻子衰变$\bar B_{(s)} \to D_{(s)}^{(*)} \ell \barν$的比率来获得该量。这种方法得益于实验和理论不确定性的显著抵消,以及对超出标准模型的重物理污染的鲁棒性。作为原理验证,我们展示当前测量将$f_s/f_d$的不确定性限制在7%,主要由现有实验不确定性主导。该方法也可用于其他涉及更重$b$强子的产率比,如$B_c$或$Λ_b$。

英文摘要

Ratios of production fractions of $b$ hadrons are a dominant source of uncertainty in many LHC analyses, in particular in measurements with $B_s$ mesons. The currently used value for $f_s/f_d$ is based on a combination of hadronic and semi-inclusive semi-leptonic decays, and relies in part on assumptions about the underlying decays that are hard to quantify. We propose an independent alternative method to obtain this quantity by measuring ratios of the exclusive semi-leptonic decays $\bar B_{(s)} \to D_{(s)}^{(*)} \ell \barν$. This method benefits from significant cancellations of both experimental and theoretical uncertainties, as well as robustness against potential contamination from heavy physics beyond the Standard Model. As a proof of principle, we show that current measurements constrain $f_s/f_d$ with an uncertainty of $7\%$, dominated by present experimental uncertainties. This method can also be applied to other ratios of production fractions involving heavier $b$ hadrons, such as $B_c$ or $Λ_b$.

2605.00179 2026-05-04 cs.SE

DEPTEX: Organization-First, Open Source Dependency Risk Monitoring

DEPTEX: 以组织为中心,开源依赖风险监控

Henry Ruckman-Utting, Vrushal Nedungadi, Taiga Okuma, LeTian Wang, Stephen Ehebald, Mohammad A. Tayebi

AI总结 DEPTEX通过图谱技术与大语言模型结合,解决开源依赖风险评估中的语义缺失问题,实现动态合规管理和主动风险控制。

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AI中文摘要

开源软件(OSS)依赖引入系统性风险,难以在大规模下管理。现有软件组成分析(SCA)和可达性工具通过将风险视为内在组件属性,忽略语义上下文,导致企业陷入僵化合规框架。我们提出了Deptex,一个以组织为中心的图谱平台,将供应链风险视为涌现属性。Deptex引入执行路径支配(EPD),融合代码属性图(CPG)切片与大语言模型(LLM)语义验证,计算漏洞的真实操作影响范围。为处理定制合规,Deptex将治理抽象为可编程的『As Code』引擎,使安全团队能够原生执行动态拉取请求策略、自定义资产层级和外部API集成。通过从被动扫描转向语义感知治理,Deptex实现了主动、高效且对齐的供应链风险管理。

英文摘要

Open-source software (OSS) dependencies introduce systemic risks that are difficult to manage at scale. Existing Software Composition Analysis (SCA) and reachability tools generate severe alert fatigue by treating risk as an intrinsic component property, ignoring semantic context and forcing enterprises into rigid compliance frameworks. We present Deptex, an organization-first, graph-based platform treating supply chain risk as emergent. Deptex introduces Execution Path Dominance (EPD), fusing Code Property Graph (CPG) slicing with Large Language Model (LLM) semantic verification to calculate a vulnerability's true operational blast radius. To handle bespoke compliance, Deptex abstracts governance into a programmable ``As Code'' engine, enabling security teams to natively enforce dynamic pull request policies, custom asset tiers, and external API integrations. By shifting from reactive scanning to context-aware governance, Deptex enables proactive, efficient, and aligned supply chain risk management.

2605.00178 2026-05-04 astro-ph.HE

A Detailed View of the Large-Scale Sloshing Cold Front in RXJ2014.8-2430

RXJ2014.8-2430中大尺度晃动冷前缘的详细视图

M. J. Sundquist, S. A. Walker, M. S. Mirakhor

AI总结 研究通过新的Chandra观测分析RXJ2014.8-2430中三个冷前缘的精细结构,发现一个可能的Kelvin-Helmholtz不稳定性或AGN活动产生的气体空洞,并测量冷前缘宽度,发现其与库仑自由程一致,表明扩散被抑制。

Comments 11 pages, 13 figures, accepted for publication in MNRAS

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AI中文摘要

我们分析了RXJ2014.8-2430中大尺度晃动冷前缘的新的144 ks深Chandra观测。先前的XMM-Newton观测显示该冷前缘距离团心约800 kpc。先前的浅Chandra数据也显示了两个更年轻的冷前缘靠近团心。新的深Chandra数据使我们能够分析这三个冷前缘的精细结构。使用beta模型减去和高斯梯度幅度过滤,我们确认了三个冷前缘的位置,并发现一个可能的大型Kelvin-Helmholtz不稳定性或AGN活动产生的气体空洞,位于团心东南侧靠近最外侧冷前缘。分析这三个冷前缘,我们测量了冷前缘的宽度,并发现它们与库仑自由程一致或更低,表明冷前缘抑制了扩散。如果该凹陷特征是空洞的内缘,我们发现其半径在200-330kpc范围内,其$PV$值在$5.7 \times 10^{60}$ - $2.7 \times 10^{61}$ erg范围内,这些值与一些最强大的气泡一致。

英文摘要

We analyze our new 144 ks deep Chandra observation of the sloshing cold front cluster RXJ2014.8-2430. Previous observations of RXJ2014.8-2430 with XMM-Newton shows evidence of a large scale, sloshing cold front around 800 kpc away from the cluster core. Previous shallow Chandra data also shows evidence of two younger cold fronts closer to the core. Our new deeper Chandra data allow us to analyze the fine, small scale structure of these three cold fronts. Using both beta model subtraction and Gaussian Gradient Magnitude filtering, we confirm the locations of the three cold fronts, as well as discover a large concave structure southeast of the cluster core near the outermost cold front, which could be a large Kelvin-Helmholtz instability or a gas cavity from AGN activity. Analyzing the three cold fronts, we measure the widths of the cold fronts and find them to be consistent with or lower than the Coulomb mean free paths within error, signifying that diffusion is suppressed across the cold fronts. If the concave feature is the inner rim of a cavity, we find that it has a radius in the range 200-330kpc, and would have $PV$ values in the range of $5.7 \times 10^{60}$ - $2.7 \times 10^{61}$ erg. These values would make it consistent with the some of the most powerful bubbles observed.

2605.00175 2026-05-04 stat.AP

Using Linked Micromaps to Explore Complex Structures in Official Statistics

利用联结微地图探索官方统计数据中的复杂结构

Randall Powers, Darcy Steeg Morris, John Eltinge, Wendy Martinez

AI总结 本文通过美国劳工统计局数据,展示联结微地图如何帮助理解人口及子群体描述统计,探索多变量关系和有序结构,并发现时空异质性模式。

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AI中文摘要

过去十年中,研究人员日益关注如何利用调查和非调查数据来指导多方利益相关者的决策。此类数据通常需要大量探索才能进行模型构建和推断的具体步骤。许多初步探索分析的关键问题集中在经验结果在地理和子群体层面的变异性程度上。此类信息通常以表格形式呈现,这可能使利益相关者和决策者难以理解和利用。为解决这些问题,本文使用美国劳工统计局的数据,展示了称为联结微地图的一套工具。这些应用展示了联结微地图如何帮助利益相关者更好地理解和查看人口及子群体的描述统计,探索多变量关系和有序结构,并发现时间与空间上的异质性模式。此外,本文还简要评论了联结微地图在模型构建和分析多重不确定性组件中的潜在用途。

英文摘要

Over the past decade, researchers have focused increasing levels of attention on the use of survey and non-survey data to inform decision-making by multiple stakeholders. Work with such data generally requires extensive exploration before a statistics practitioner focuses on specific steps in model building and inference. For many of the resulting initial exploratory analyses, crucial issues center on the extent to which empirical results may vary over geography and subpopulations. Such information is usually presented in tabular form, which can be difficult for stakeholders and decision makers to understand and to utilize. To address these issues, this paper uses data from the U.S. Bureau of Labor Statistics to illustrate a suite of tools known as linked micromaps. These applications show how linked micromaps can help stakeholders better understand and view descriptive statistics for populations and subpopulations, explore multivariate relationships and ordinal structure, and discover patterns of heterogeneity across time and space. In addition, this paper comments briefly on the prospective use of linked micromaps in model-building and analysis of multiple components of uncertainty.

2605.00173 2026-05-04 math.DS

Transversality for Interval Translation Maps

区间翻译映射的横截性

Kostiantyn Drach, Leon Staresinic, Sebastian van Strien

AI总结 本文研究了区间翻译映射的动力学子空间横截性定理,为系统扰动控制提供了理论支持,并在稳定性刻画和拓扑版本的Boshernitzan-Kornfeld猜想证明中起到关键作用。

Comments arXiv admin note: substantial text overlap with arXiv:2411.14312

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AI中文摘要

区间翻译映射(ITM)是在有限划分I₁,…,Iₙ的区间I上定义的分段平移T∶I→I。与经典区间交换变换(IET)不同,ITM不要求子区间的像互不相交;特别地,ITM不假设是双射的。因此,ITM为IET提供了自然的非可逆推广。本文证明了动态定义的向量子空间族的横截性定理,该定理编码了给定ITM的动力学。作为结果,我们建立了扰动结果,精确控制子区间内的首次返回动力学,同时保持系统其余全局动力学。这些结果在ITM稳定性刻画证明和拓扑版本的Boshernitzan-Kornfeld猜想证明中起到关键作用。

英文摘要

An \textit{interval translation map} (ITM) is a piece-wise translation $T \colon I \to I$ defined on a finite partition $I_1, \ldots, I_r$ of an interval $I$ into $r \ge 2$ subintervals. In contrast to classical interval exchange transformations (IETs), we do not require that the images of these subintervals are disjoint; in particular, ITMs are not assumed to be bijective. Thus, ITMs provide a natural non-invertible generalisation of IETs. In this paper, we prove a transversality theorem for a family of dynamically defined vector subspaces that encode the dynamics of a given ITM. As a consequence, we establish a perturbation result that gives a precise control of the first return dynamics to subintervals in $I$, while preserving the remaining global dynamics of the system. Beyond their independent interest, these results are a key technical ingredient in the proof of the Characterisation of Stability of ITMs and in the establishment of the topological version of the Boshernitzan--Kornfeld Conjecture.

2605.00170 2026-05-04 astro-ph.EP

Smaller Than Earth Habitability Model (STEHM): The Lower Size Limit for Atmosphere Retention in the Habitable Zone

比地球更小的宜居模型(STEHM):宜居带内大气保留的下限大小

Michelle L. Hill, Stephen R. Kane, Bradford J. Foley, Laura K. Schaefer

AI总结 STEHM研究了在宜居带内,行星能维持大气的最小大小,发现0.8地球半径以上的行星在地球条件下可维持大气,而更小的行星则无法维持,初始碳储量是关键因素。

Comments 18 Pages, 11 Figures, Accepted for Publication in PSJ

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AI中文摘要

随着系外行星观测技术的进步,发现越来越小的行星,引发了寻找宜居行星的关键问题:行星能小到什么程度仍能维持大气?我们介绍了Smaller Than Earth Habitability Model(STEHM),该模型研究了从1.0R_⊕到0.5R_⊕的行星能维持长期(多十亿年)大气的最小大小。该模型基于一个停滞板块行星绕太阳类恒星轨道运行。我们的模型表明,在太阳类恒星的地球类默认条件下,大于等于0.8R_⊕的行星可以维持其大气,而更小的行星会失去大气。默认地球类值的微小变化导致行星大小边界结果的微小变化,某些变化允许大于等于0.7R_⊕的行星维持其大气。初始碳储量是大气保留最显著的影响因素,但需要比地球值大几个数量级才能显著影响大气保留的持续时间。具有大量初始碳储量、大量热产生元素、较低的初始地幔温度和低核心半径比例的行星表现出最佳的大气保留能力。我们的研究结果表明,小行星的大气保留严重依赖于其形成条件和早期演化,为未来类地系外行星的观测和潜在宜居性提供了重要约束。

英文摘要

With recent advances in exoplanet observational techniques enabling the discovery of increasingly smaller planets, a crucial question emerges in the search for habitable planets: how small can a planet be and still maintain an atmosphere? We present results from the Smaller Than Earth Habitability Model (STEHM) which examines how small a planet can be and still maintain a long-term (multi-gigayear) atmosphere for planets from 1.0$R_\oplus$ down to 0.5$R_\oplus$. The model is based on a stagnant lid planet orbiting within the habitable zone of a sun-like star. Our model demonstrates that planets $\geq$0.8$R_\oplus$ can maintain their atmospheres under our Earth-like default conditions for a solar analog star, while smaller planets lose their atmospheres. Variations from the default Earth-like values cause mostly minor variations to the planet size boundary results, with some changes allowing $\geq$0.7$R_\oplus$ planets to maintain their atmosphere. Initial carbon inventory emerges as the most influential parameter for atmospheric retention, though orders of magnitude difference to Earth values are required to make a significant difference to longevity of atmospheric retention. Planets with substantial initial carbon content, large amounts of heat producing elements, cool initial mantle temperatures and low core radius fractions show the best atmospheric retention capabilities. Our results indicate that atmospheric retention on small planets depends strongly on their formation conditions and early evolution, providing important constraints for future observations of rocky exoplanets and their potential habitability.

2605.00168 2026-05-04 physics.flu-dyn

Curvature-corrected sloshing spectra for cylindrical tanks in microgravity

修正曲率的圆柱形储罐晃荡谱

Gianni Cassoni

AI总结 本文研究了微重力环境下圆柱形储罐中曲率对晃荡频率的影响,提出一种半解析边界运算方法,揭示了曲率引起的频率偏移的物理机制,结果表明曲率会改变低阶谱并影响航天器应用的动力学尺度。

Comments 24 pages, 8 figures, 3 tables. Submitted to Journal of Fluid Mechanics

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AI中文摘要

在微重力环境下,部分填充的圆柱形储罐通常由弯曲的平衡毛细管表面而非几乎平坦的自由表面所限制。这会同时改变液体的本体惯性和毛细力恢复力,使得平坦界面的晃荡频率在线性范围内也可能不准确。这种效应在Bond数为一量级或更小时尤为重要,恰好是毛细力主导推进剂管理的区域。本文重新审视了经典的圆柱形弯曲毛细管特征值问题,针对毛细力-重力晃荡的轴对称Young-Laplace平衡情况。推导出一种半解析的边界运算方法,保留了圆柱形贝塞尔结构,并能精确恢复平坦界面极限。其主要优势在于将本体的Dirichlet-Neumann运算符和线性化曲率运算符作为独立组成部分,从而明确揭示曲率引起的频率偏移的物理来源。结果表明,平衡曲率会耦合径向模态并改变低阶谱一次$Bo \lesssim 1$。凹形毛细管降低基频,而凸形毛细管提高基频,但通常会降低高阶分支。湿润和非湿润配置之间的不对称性被发现主要是动能性的,主要由Dirichlet-Neumann运算符而非毛细力项所承载。因此,曲率毛细管应作为圆柱形微重力晃荡领先阶模型的一部分进行考虑,而非作为二次修正,以确保降阶预测能捕捉到航天器应用的相关动力学尺度。

英文摘要

In microgravity, a partially filled cylindrical tank is generally bounded by a curved equilibrium meniscus rather than by an almost flat free surface. This modifies both the bulk liquid inertia and the capillary restoring force, so flat-interface sloshing frequencies can become inaccurate even in the linear regime. This effect matters once the Bond number is of order unity or smaller, precisely the regime relevant to capillarity-dominated propellant management. This study revisits the classical cylindrical curved-meniscus eigenvalue problem for capillary-gravity sloshing about axisymmetric Young-Laplace equilibria. A semi-analytical boundary-operator formulation is derived that preserves the cylindrical Bessel structure and recovers the flat-interface limit exactly. Its main advantage lies in treating the bulk Dirichlet-Neumann operator and the linearised curvature operator as distinct components, thereby making the physical origin of curvature-induced frequency shifts explicit. The results show that equilibrium curvature couples radial modes and alters the low-order spectrum once $Bo \lesssim 1$. Concave menisci lower the fundamental frequency, whereas convex menisci raise it while often lowering higher branches. The asymmetry between wetting and non-wetting configurations is found to be predominantly kinetic, being carried mainly by the Dirichlet-Neumann operator rather than by the capillary term. Curved menisci should therefore be treated as part of the leading-order model of cylindrical microgravity sloshing, not as a secondary correction, if reduced-order predictions are to capture the relevant dynamical scales for spacecraft applications.

2605.00167 2026-05-04 cond-mat.dis-nn physics.ao-ph

Data-Driven Modelling to predict forest fire spread in the Patagonian region in Argentina

数据驱动建模用于预测阿根廷巴塔哥尼亚地区森林火灾蔓延

Lucas Becerra, Monica Malen Denham, Alejandro B. Kolton, Karina Laneri

AI总结 本文提出基于反应-扩散-对流模型的数据驱动方法,结合高精度地形和植被数据,通过遗传算法和XGBoost优化参数,提升火灾预测精度,为森林管理提供新方法。

Comments 29 pages, 8 figures

Journal ref Ecological Modelling, Volume 518, August 2026, 111618

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AI中文摘要

森林火灾是影响森林生态系统最严重的干扰因素之一,2025年阿根廷巴塔哥尼亚地区仅烧毁了超过5万公顷的土地。本研究实施了反应-扩散-对流(RDC)模型,以模拟斯蒂芬和马丁湖地区火灾的传播,该地区受到火灾严重影响。通过整合高分辨率的坡度、风速和植被地图,我们进行了三个递增复杂度的计算实验,以模拟火灾在异质景观中的传播。我们采用遗传算法(GA)通过最大化模拟和参考烧毁区域的空间重叠来恢复参考模型参数。随后,使用XGBoost对参数估计进行优化以提高准确性。结果表明,GA在所有场景中都能准确恢复参考参数,而XGBoost的微调显著提高了简单情况的准确性。这种集成框架为估计难以测量的火灾参数提供了系统方法,展示了混合计算方法在火灾建模和森林管理中的潜力。

英文摘要

Wildfires are among the most severe disturbances affecting forest ecosystems, with over 50,000 hectares burned in Patagonia, Argentina, during 2025 alone. This study implements a Reaction-Diffusion-Convection (RDC) model to simulate wildfire spread in the Steffen and Martin Lakes area, a region severely impacted by fires. By integrating high-resolution maps of slope, wind velocity, and vegetation, we conducted three computational experiments of increasing complexity to simulate fire propagation across heterogeneous landscapes. We employed a Genetic Algorithm (GA) to recover reference model parameters by maximizing the spatial overlap between simulated and reference burned areas. Subsequently, parameter estimates were refined using XGBoost to improve accuracy. Results demonstrate that the GA accurately recovers reference parameters across all scenarios, while the XGBoost fine-tuning significantly enhances accuracy in simpler cases. This integrated framework offers a systematic approach for estimating difficult-to-measure wildfire parameters, demonstrating the potential of hybrid computational methods for wildfire modeling and forest management.

2605.00166 2026-05-04 physics.acc-ph

Development of Ultra High Power Compact X-Band Pulse Compressor

超高功率紧凑X波段脉冲压缩器的发展

Ankur Dhar, Mohamed A. K. Othman, Valery A. Dolgashev

AI总结 本文提出了一种新型11.424 GHz SLED型射频脉冲压缩器,用于驱动高梯度X波段光注入器,通过压缩20 ns脉冲实现更高峰值功率,实验验证了其在高功率鲁棒性和紧凑设计方面的优势。

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AI中文摘要

本文提出了一种新型11.424 GHz SLED型射频脉冲压缩器,用于驱动高梯度X波段光注入器,通过压缩20 ns脉冲实现更高峰值功率,实验验证了其在高功率鲁棒性和紧凑设计方面的优势。

英文摘要

We demonstrate a new 11.424 GHz SLED-type RF pulse compressor for powering high-gradient X-band photoinjectors with pulse lengths around 20 ns. RF pulse compression provides a practical path to higher peak power at the cost of pulse length for various applications such as RF deflectors for electron beam diagnostics on free electron lasers. Our new compact pulse compressor uses spherical cavities supporting axially symmetric TE modes which have minimal electric fields on the cavity surfaces, intended to improve high-power robustness as compared to existing compact spherical SLEDs which use a TE dipole mode. We present the design of this pulse compressor composed of two spherical cavities and a waveguide hybrid. The two cavities and hybrid have TE01 circular waveguide ports. This pulse compressor was built and high power tested at SLAC. These tests demonstrated a peak power of 317 MW by compressing 52 MW, 1 μs pulses generated by a SLAC XL-4 klystron. The full-width at half-maximum of this compressed pulse was 27 ns. We conjecture that this development demonstrates a viable route to reaching the high-gradient, short pulse regime for accelerating structures and RF photoinjectors.

2605.00165 2026-05-04 physics.plasm-ph

Characterization of ELM Pacing via Vertical Jogs on DIII-D

通过DIII-D上的垂直急行表征ELM节律

Kei Yasoda, Dario Panici, Andrew Oak Nelson, Florian M. Laggner, Sangkyeun Kim, Egemen Kolemen

AI总结 研究通过垂直等离子体振荡触发ELM,发现垂直急行可提高ELM频率并减少能量损失,同时降低碳杂质浓度和热通量。

Comments 20 pages, 9 figures

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AI中文摘要

边缘局域模(ELM)通过垂直等离子体振荡或急行在DIII-D上已成功实现。快速垂直运动的等离子体向X点移动可有效触发ELM。以20Hz频率垂直振荡等离子体,使ELM频率从约5Hz增加到20Hz。向下急行可在一个周期内触发多个ELM。触发频率高于自然频率的ELM导致存储能量减少幅度较小,从约10%降至低于1%。因此, divertor的峰值热通量减少了一倍。此外,碳杂质浓度也有所降低。在下单null(LSN)配置中,X点运动比等离子体顶部更慢且更小。因此,观察到等离子体横截面和体积的减小。为了理解急行触发ELM的机制,构建了一个边缘托卡马克电流的玩具模型,并用DIII-D实验数据测试。实验数据和模型表明,当等离子体向下移动向X点时,在边缘区域局部诱导了净正托卡马克电流。ELITE稳定性分析表明,该电流将等离子体状态推过剥离边的剥离-膨胀稳定性边界,进入不稳定区域,从而触发ELM。

英文摘要

Edge localized mode (ELM) pacing via vertical plasma oscillations or jogging has been successfully demonstrated on DIII-D. Rapid vertical movement of the plasma toward the X-point has been shown to effectively trigger ELMs. By vertically oscillating the plasma at a rate of 20 Hz, the ELM frequency increased from $\sim$5~Hz, the natural ELM frequency in similar DIII-D discharges, to 20~Hz. Downward jogs have been observed to trigger multiple ELMs in one cycle. ELMs triggered at higher than natural frequencies lead to smaller decreases in stored energy, from ~10\% to as little as below 1\%. As a consequence, the peak heat flux to the divertor has been observed to be reduced by a factor of $\sim$2. In addition, a reduction in the carbon impurity concentration has been observed. During downward jogs in the lower single null (LSN) configuration, the X-point movement is slower and smaller than the top of the plasma. As a result, a reduction in the plasma cross section and hence volume has been observed. To understand the mechanism of ELM triggering by jogging, a toy model of the edge toroidal current has been built and tested with DIII-D experiment data. The experimental data and model suggest that when the plasma moves down towards the X-point, a net positive toroidal current is locally induced in the edge region. ELITE stability analysis suggests that this current pushes the plasma state across the peeling side of the peeling-ballooning stability boundary into the unstable region triggering ELMs.

2605.00164 2026-05-04 math.AG

Stable Wild Vafa-Witten Bundles on the Projective Plane

在复射影平面上的稳定野瓦夫-文特 bundles

Robert Cornea

AI总结 研究复射影平面上稳定野瓦夫-文特 bundles 的几何性质,计算稳定对的模空间维数,并分类当底层 rank-two bundles 分裂或为射影平面乘积上线丛的推 forward 时的稳定对,最后分析自然的 $\mathbb{C}^*$-作用的固定点区域。

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AI中文摘要

本文探讨复射影平面上稳定野瓦夫-文特 bundles 的几何结构。具体而言,我们考虑稳定 rank-two 对 $(E,Φ)$,其中 $E\to\mathbb{P}^2$ 是 rank-two 光滑向量丛,$Φ\in H^0(\mathbb{P}^2,\mathrm{End}_0E\otimes\mathcal{O}(d))$ 对于 $d\geq0$,并计算此类稳定对的模空间的维数。此外,我们分类当底层 rank-two bundles 分裂或为射影平面乘积上线丛的推 forward 时的稳定对。最后,我们研究自然 $\mathbb{C}^*$-作用在模空间上的固定点区域。

英文摘要

This work explores the geometry of stable wild Vafa-Witten bundles over the complex projective plane $\mathbb{P}^2$. Specifically, we consider stable rank-two pairs $(E,Φ)$, with $E\to\mathbb{P}^2$ a rank-two holomorphic vector bundle and $Φ\in H^0(\mathbb{P}^2,\mathrm{End}_0E\otimes\mathcal{O}(d))$ for $d\geq0$, and compute the dimension of the moduli space of such stable pairs. Moreover, we classify stable pairs $(E,Φ)$ when the underlying rank-two bundle $E$ splits or is the push-forward of a line bundle on $\mathbb{P}^1\times\mathbb{P}^1$. Lastly, we examine the fixed point locus of the natural $\mathbb{C}^*$-action on the moduli space.

2605.00163 2026-05-04 physics.space-ph astro-ph.SR

Radial Dependency of ICME-associated Particle Acceleration Processes: Statistical Multipoint Observations from 2016-2023

ICME相关粒子加速过程的径向依赖性:2016-2023年多点观测的统计分析

Malik H. Walker, Robert C. Allen, George C. Ho, Glenn M. Mason, Christina M. S. Cohen, Christina Lee, Christian Möstl, Emma E. Davies, Eva Weiler

AI总结 研究ICME驱动激波在传播过程中径向演化与SEP和ESP强度、成分及加速机制的关系,通过多点观测数据揭示加速效率随距离变化的规律。

Comments 16 pages, 8 figures, 2 tables, submitted to A&A

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AI中文摘要

在日球冠状物质抛射(ICME)传播过程中,ICME驱动激波的演变及其与其他日球风结构、行星体和形态变化的相互作用会影响其相关激波的粒子加速效率和传输效应。尽管这些过程的机理已有所研究,但ICME驱动激波在传播过程中径向演化与由此产生的渐进式太阳高能粒子(SEP)和高能风暴粒子(ESP)强度、成分及加速之间的联系尚未完全理解。当前分布在不同日心距离的航天器提供了统计分析ICME驱动激波上粒子群和加速机制径向依赖性的良好机会。我们编译了一个包含2016-2023年39个多点ICME事件的数据库,这些事件由至少两架以下航天器在 situ 观测:帕克太阳探测器(PSP)、太阳轨道器、ACE、风、和STEREO-A。利用这些航天器提供的磁场、等离子体和离子成分数据,我们推导出本地激波和ESP谱形参数。通过比较不同ICME传播阶段这些参数的变化,我们分析了本地激波条件演变与谱形之间的联系。我们发现证据表明,在ICME处于0.7 au以内时,激波加速效率随日心距离增加而一致提高,随后在更远距离时加速效率下降。

英文摘要

During the propagation of interplanetary coronal mass ejections (ICMEs), evolution of the ICME-driven shock along with interactions with other solar wind structures, planetary bodies, and general changes to their morphology can alter particle acceleration efficiency and transport effects at their associated shocks. While the underlying mechanisms for these processes have been studied, the connection between the radial evolution of the ICME-driven shock during propagation and resulting gradual Solar Energetic Particle (SEP)and Energetic Storm Particle (ESP) intensities, composition, and acceleration has yet to be fully understood. The current distributed array of spacecraft at varying heliocentric distances provides a welcome opportunity to statistically analyze the radial dependency of particle populations and acceleration mechanisms present at ICME-driven shocks. We compile a database of 39 multipoint ICME events from 2016-2023, which are observed in situ by at least two of the following spacecraft: Parker Solar Probe (PSP), Solar Orbiter, ACE, Wind, and STEREO-A. Using the magnetic field, plasma, and ion compositional data provided by these spacecraft, we derive both local shock and ESP spectral shape parameters. By comparing the changes in these parameters at different stages of ICME propagation, we analyze the connection between the evolution of the local shock conditions and the spectral shape. We find evidence to suggest a consistent increase in shock acceleration efficiency with heliocentric distance while the parent ICME is within 0.7 au, followed by a reduction in shock efficiency at further distances.

2605.00162 2026-05-04 astro-ph.SR astro-ph.IM physics.space-ph

EMBER: Machine-Learning Detection of Modulated Ion Acoustic Waves and Associated Core-Electron Heating in the Solar Wind with Parker Solar Probe

EMBER:利用机器学习检测调制的离子声波及关联的核心电子加热现象在日风中

Argyro Sasli, Karish Seebaluck, Chris Colpitts, Michael Coughlin

AI总结 本文提出EMBER系统,通过机器学习检测日风中调制的离子声波及核心电子加热现象,实现高精度识别,具有高召回率和低误报率。

Comments 16 pages, 5 figures

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AI中文摘要

调制的离子声波(IAWs)——包括触发的离子声波(TIAWs)和频率分散的离子声波(FDIAWs)——正逐渐被认可为通过非线性波粒相互作用在日风中高效驱动电子加热的机制。在帕克太阳探测器(PSP)FIELDS突发模式档案中识别这些事件迄今为止依赖于专家视觉检查,无法扩展到整个任务。我们提出了EMBER(从调制突发模式事件识别中电子加热),一个开源的流水线,将PSP FIELDS数字突发内存(DBM)电压突发转换为对数缩放的傅里叶频谱图,并应用了一个多探测器、背景为主的异常检测套件。该套件结合了物理驱动的探测器、经典离群点探测器和深度学习探测器。EMBER集合在1%的假阳性率(1个假阳性每100个保留背景)下恢复了93%的异常事件。同时的SWEAP/SPAN诊断显示,被标记的区间表现出垂直方向电子温度高于绝热冷却预期,并且Te/Ti升高,重现了先前手动研究中确立的优先加热现象学,无需在检测步骤中使用电子温度。

英文摘要

Modulated ion acoustic waves (IAWs) -- including triggered ion acoustic waves (TIAWs) and frequency-dispersed ion acoustic waves (FDIAWs) -- are increasingly recognized as efficient drivers of electron heating in the solar wind through nonlinear wave-particle interactions. Identification of these events in the Parker Solar Probe (PSP) FIELDS burst-mode archive has so far relied on expert visual inspection and does not scale to the full mission. We present EMBER (Electron heating from Modulated Burst-mode Event Recognition), an open-source pipeline that converts PSP FIELDS Digital Burst Memory (DBM) voltage bursts into log-scaled Fourier spectrograms and applies a multi-detector, background-only anomaly detection suite. The suite combines physics-motivated detectors, classical outlier detectors, and deep learning detectors. The EMBER ensemble recovers 93% of the anomalous events at 1% FAR (1 false positive per 100 held-out backgrounds). Coincident SWEAP/SPAN diagnostics show that flagged intervals exhibit core perpendicular electron temperatures above the adiabatic cooling expectation and elevated Te/Ti, reproducing the preferential-heating phenomenology established by prior manual studies without any use of electron temperatures in the detection step.

2605.00160 2026-05-04 math.OC math.PR

Approximations and Learning for Decentralized Stochastic Control and Near Optimal Finite Window Policies

近似与学习用于去中心化随机控制及近最优有限窗口策略

Omar Mrani-Zentar, Serdar Yuksel

AI总结 本文研究去中心化随机控制问题,提出在一般标准Borel空间下,通过有限窗口信息策略实现近最优局部策略,并证明其稳定性条件及Q学习算法的收敛性。

Comments arXiv admin note: text overlap with arXiv:2408.13828

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AI中文摘要

去中心化随机控制问题因信息结构的细微差别而难以研究,许多经典方法难以应用。本文考虑一般标准Borel空间下的此类问题,采用两种相关信息结构:(a) 一步延迟信息共享模式(OSDISP),即代理在一步延迟后共享信息;(b) K步周期性信息共享模式(KSPISP),即信息周期性共享。已知OSDISP和KSPISP问题可通过集中化方法解决,即代理以集中控制器的视角看待问题,利用公共信息制定函数值动作(局部策略),将每个代理的私人信息映射到原始问题的最优动作。本文为KSPISP和OSDISP问题提供了严格的近似结果和性能界,这些结果来自用有限滑动窗口信息替代完整公共信息,并建立了此类策略的近最优性。后者依赖于预期总变分中的预测稳定性条件。此外,本文还证明在提供的信息结构下,对应的Q学习算法(在量化或有限记忆形式下)渐近收敛到近最优解。虽然文献中已提出限制性和假设性条件,但本文的贡献是提供迄今为止首次明确的条件和严格的近似和学习结果,用于一般空间中的此类去中心化问题。

英文摘要

Decentralized stochastic control problems are difficult to study due to information structure dependent subtleties, which prevent many classical methods in stochastic control from being applicable. In this paper we consider such problems with general standard Borel spaces under two related information structures. (a) the one-step delayed information sharing pattern (OSDISP) where agents share their information with one-step delay, and (b) the $K$-step periodic information sharing pattern (KSPISP), where information is shared periodically. It is known that OSDISP and KSPISP problems admit a centralized reduction where the agents view the problem from the perspective of a centralized controller that uses the common information to prescribe function valued actions (local policies) which map each agent's private information to an optimal action in the original problem. We provide rigorous approximation results and performance bounds for the KSPISP and OSDISP problems, which results from replacing the full common information by a finite sliding window of information and we establish near optimality of such policies. The latter depends on a predictor stability condition in expected total variation. As a further contribution, we show that under the information structures provided, corresponding Q-learning algorithms (in quantized or finite memory forms) converge asymptotically to near optimal solutions. While restrictive and hypothetical conditions have been presented in the literature, our contributions are thus to provide, to our knowledge, the first explicit conditions and rigorous approximation and learning results for such decentralized problems with general spaces.

2605.00158 2026-05-04 math.OC cs.GT cs.SY eess.SY

Moral Hazard in LTI Dynamics: A Hypothesis Testing Approach

LTI动态中的道德风险:假设检验方法

Jaewon Jeong, Pan-Yang Su, S. Shankar Sastry, Anil Aswani

AI总结 本文研究了在信息不对称条件下设计控制系统的激励机制,通过假设检验方法确定最优支付方案以激励代理选择最小化二次成本的控制器。

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AI中文摘要

许多激励设计问题必须应对由于效率非观测(逆向选择)或努力非观测(道德风险)导致的信息不对称。尽管已有大量文献研究控制系统的激励设计,但在信息不对称条件下设计控制系统的激励机制仍研究较少。本文考虑了控制系统中的道德风险模型。在我们的模型中,控制系统由具有过程噪声的(仿射)线性时不变(LTI)系统描述。存在一个代理,可以选择(在两个选择中)应用线性状态反馈控制器到LTI系统,其中一个状态反馈控制器的控制输入二次成本高于另一个。我们的目标是设计一种支付方案,激励代理选择最小化系统状态二次成本加上时间折扣支付金额的控制器,同时考虑到代理承担控制成本并对其时间折扣支付具有风险规避性。我们将问题 formulation 为一个约束优化问题,并证明对于在固定(但可优化)时间 horizon 后给出的支付,最优支付方案使用似然比假设检验确定支付金额。我们通过将推导出的最优支付方案应用于两个示例:电力系统中的负荷频率控制(LFC)和体重减轻的健康干预措施,数值演示了我们的结果。

英文摘要

Many incentive design problems must contend with information asymmetries due to non-observation of efficiency (adverse selection) or non-observation of effort (moral hazard). And although a growing body of literature considers incentive design in control systems, the problem of designing incentives for control systems under information asymmetries has been less well-studied. This paper considers a model of moral hazard within control systems. In our model, the control system is described by an (affine) linear time-invariant (LTI) system with process noise. There is an agent who gets to choose (from between two choices) a linear state-feedback controller to apply to the LTI system, with one of the state-feedback controllers having a higher quadratic cost on the control inputs than the other. Our goal is to design a payment scheme that incentivizes the agent to choose the state-feedback controller that minimizes a quadratic cost on system states plus the time-discounted payment amount, subject to the understanding that the agent bears the control cost while being risk-averse with respect to their time-discounted payment. We formulate the problem as a constrained optimization, and prove that for a payment given after a fixed (but optimizable) time horizon the optimal payment scheme chooses the payment amount using a likelihood ratio hypothesis test. We numerically demonstrate our results by applying the derived optimal payment scheme to two examples: load frequency control (LFC) in power systems and wellness interventions for body weight loss.

2605.00157 2026-05-04 quant-ph math-ph math.MP math.PR

Asymptotic Replacement for Quantum Channel Products with Applications to Inhomogeneous Matrix Product States

量子通道乘积的渐近替代及其在非均匀矩阵积态中的应用

Lubashan Pathirana

AI总结 本文研究了有限维量子通道乘积的迹-多布里索夫理论,应用于确定性和平稳的非均匀矩阵积态,探讨了渐近替代、记忆丢失与收敛性。

Comments 79 pages

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AI中文摘要

我们为有限维量子通道乘积发展了产品层面的迹-多布里索夫理论,并将其应用于左规范CPTP gauge中的确定性和平稳随机非均匀矩阵积态。对于通道乘积,中心化迹-多布里索夫系数量化了输入态的残余依赖性,其衰减是迹范数遗忘的判据。在确定性设定中,这种衰减等同于渐近替代由移动替代通道实现。对于双侧乘积,回溯遗忘产生一个唯一的边界态,确定了规范替代族。对于平稳随机CPTP协循环,乘积系数的子乘法性导致迹-多布里索夫李雅普诺夫指数。我们证明该指数的几乎必然负性等价于淬火迹范数记忆丢失,并给出指数前向和回溯收敛到唯一动态平稳随机替代通道。当通道环境的ρ-混合profile趋于零时,我们获得退火超多项式估计,而独立性给出退火指数估计。最后,我们将这些估计转移到辅助转移映射为CPTP的非均匀矩阵积态,这些通道估计转移到确定性和平稳随机非均匀MPS,给出无限体积极限的迹闭有限体积状态,定量边界稳定性以及由相同辅助乘积系数支配的相关性界。

英文摘要

We develop a product-level trace-Dobrushin theory for finite-dimensional quantum channel products and apply it to deterministic and stationary random inhomogeneous matrix product states in left-canonical CPTP gauge. For a product of channels, the centered trace-Dobrushin coefficient quantifies the residual dependence on the input state, and its decay is the criterion for trace-norm forgetting. In the deterministic setting, this decay is equivalent to asymptotic replacement by a moving replacement channel. For two-sided products, pullback forgetting produces a unique boundary state, which determines the canonical replacement family. For stationary random CPTP cocycles, submultiplicativity of the product coefficient yields a trace-Dobrushin Lyapunov exponent. We prove that the almost sure negativity of this exponent is equivalent to quenched trace-norm memory loss and gives exponential forward and pullback convergence to a unique dynamically stationary random replacement channel. When the \(\varrho\)-mixing profile of the channel environment tends to zero, we obtain annealed super-polynomial estimates, while independence gives annealed exponential estimates. Finally, we transfer these estimates to inhomogeneous matrix product states whose auxiliary transfer maps are CPTP. These channel estimates transfer to deterministic and stationary random inhomogeneous MPS, giving infinite-volume limits of trace-closed finite-volume states, quantitative boundary stability, and correlation bounds governed by the same auxiliary product coefficients.

2605.00156 2026-05-04 cs.MM cs.CR

RoboKA: KAN Informed Multimodal Learning for RoboCall Surveillance System

RoboKA:基于KAN的多模态学习用于RoboCall监控系统

Nitin Choudhury, Nikhil Kumar, Aditya Kumar Sinha, Abhijeet Anand, Hossein Salemi, Orchid Chetia Phukan, Hemant Purohit, Arun Balaji Buduru

AI总结 本文提出RoboKA,一种基于KAN的多模态融合框架,用于建模音频和语言线索之间的非线性交互,以提高RoboCall监控的召回率和F1分数。

Comments Accepted to the International Conference on Multimedia & Expo (ICME) 2026, 7th International Workshop on Surveillance Data Processing

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AI中文摘要

由于公共数据集访问受限和隐私问题,RoboCall监控研究面临广泛探索的阻碍。本文首先整理了Robo-SAr合成RoboCall数据集,包含约200个不良和1200个合法的合成RoboCall样本,涵盖三个现实对抗轴:心理语言学操纵的转录文本、引发情绪的语音和克隆声音。我们进一步提出了RoboKA,一种基于Kolmogorov-Arnold网络(KAN)的多模态融合框架,用于建模音频和语言线索之间的结构非线性交互,以表征多样的对抗性RoboCall策略。RoboKA首先利用跨模态对比学习对潜在模态表示进行对齐,并将结果嵌入传递给KAN投影头进行最终分类。我们对RoboKA在域内和域外设置中与强大的单模态和多模态基线进行基准测试,发现RoboKA在召回率和F1分数上均优于所有基线。

英文摘要

Wide exploration on robocall surveillance research is hindered due to limited access to public datasets, due to privacy concerns. In this work, we first curate Robo-SAr, a synthetic robocall dataset designed for robocall surveillance research. Robo-SAr comprises of ~200 unwanted and ~1200 legitimate synthetic robocall samples across three realistic adversarial axes: psycholinguistics-manipulated transcripts, emotion-eliciting speech, and cloned voices. We further propose RoboKA, a Kolmogorov-Arnold Network (KAN)-based multimodal fusion framework designed to model structured nonlinear interactions between acoustic and linguistic cues that characterize diverse adversarial robocall strategies. RoboKA first leverages cross-modal contrastive learning to align latent modality representations and feeds the resulting embeddings to a KAN-projection head for final classification. We benchmark RoboKA against strong unimodal and multimodal baselines in both in-domain and out-of-domain setups, finding RoboKA to surpass all baselines in terms of recall and F1-score.

2605.00154 2026-05-04 astro-ph.EP

Confirmation of Fe I on MASCARA-5 b's Dayside Observed With EXPRES

确认MASCARA-5 b的昼面Fe I通过EXPRES观测

James T. Sikora, Joe Llama, Rachael M. Roettenbacher, Elisabeth M. Brann, Jean-Michel Désert, Alex S. Polanski, Malena Rice, Lily Zhao

AI总结 通过EXPRES观测确认MASCARA-5 b昼面Fe I发射线,揭示热倒置大气层,为行星大气化学和热结构研究提供新数据。

Comments 15 pages, 11 figures; accepted for publication in AJ

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AI中文摘要

MASCARA-5~b/TOI-1431~b是围绕明亮Am星的超热木星,其轨道周期为2.650237±0.000003天,等效温度为2370±70K,质量3.12±0.18M_jup,半径1.49±0.05R_jup。最近利用PEPSI@LBT在行星凌后相的时序观测揭示了Fe~{\sc i}发射线,表明热倒置大气。这些观测表明MASCARA-5~b适合通过发射光谱进行大气研究,促使进一步观测以约束大气化学、热结构和动态。本文呈现了利用EXPRES@LDT获得的凌前时序观测,分析确认了MASCARA-5~b昼面气体相Fe~{\sc i}的检测(从两晚观测获得5.5σ显著性),并发现热层温度分别为约2000K和4500K。未发现Fe~{\sc ii}和Cr~{\sc i}的可能检测。此外,凌前信号表现出非可忽略的蓝移-3.2±1.4km/s,可能由风引起。

英文摘要

MASCARA-5~b/TOI-1431~b is an ultra-hot Jupiter \citep[$P_{\rm orb}=2.650237\pm0.000003\,{\rm d}$, $T_{\rm eq}=2370\pm70\,{\rm K}$, $M_{\rm p}=3.12\pm0.18\,M_{\rm Jup}$, $R_{\rm p}=1.49\pm0.05\,R_{\rm Jup}$;][]{addison2021} orbiting a bright Am star ($V=8.0\,{\rm mag}$). Recent time-series observations obtained with PEPSI@LBT during the planet's post-eclipse phases have revealed Fe~{\sc i} emission lines indicative of a thermally inverted atmosphere. These observations demonstrate that MASCARA-5~b is well-suited to atmospheric characterization via emission spectroscopy, thereby motivating further follow-up observations covering additional orbital phases to constrain the planet's atmospheric chemistry, thermal structure, and dynamics. Here we present pre-eclipse time-series observations obtained with the high-resolution optical spectrograph EXPRES@LDT. Our analysis confirms the previous detection of gas-phase Fe~{\sc i} on MASCARA-5~b's dayside (with a $5.5σ$ significance obtained from two nights of observations) and the fact that the thermal profile is inverted with lower and upper temperatures $\sim2000\,{\rm K}$ and $\sim4500\,{\rm K}$, respectively. A search for Fe~{\sc ii} and Cr~{\sc i} did not yield any plausible detections. We also find that the pre-eclipse signal exhibits a non-negligible blueshift of $-3.2\pm1.4\,{\rm km/s}$ potentially caused by winds.

2605.00153 2026-05-04 astro-ph.IM

Radiation Total Dose for PRIMA: Cold Exposure with Alpha Particles

PRIMA的辐射总剂量:阿尔法粒子的冷暴露

Elijah Kane, Chris Albert, Andrew Beyer, Charles, Bradford, Pierre Echternach, Logan Foote, Jason Glenn, Henry, LeDuc, Hien Nguyen, Thomas Stevenson, Brian Zhu, Jonas Zmuidzinas

AI总结 PRIMA任务需评估阿尔法粒子在L2轨道对探测器的影响,通过低温辐射实验研究高能粒子对探测器灵敏度的损害机制。

Comments 6 pages, 12 figures

Journal ref in IEEE Transactions on Applied Superconductivity, vol. 36, no. 6, pp. 1-6, Sept. 2026, Art no. 2401006

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AI中文摘要

PRIMA任务需评估阿尔法粒子在L2轨道对探测器的影响,通过低温辐射实验研究高能粒子对探测器灵敏度的损害机制。

英文摘要

The Probe far-Infrared Mission for Astrophysics (PRIMA) is a far-infrared (24-261 micron wavelengths) probe-class space observatory currently under Phase A study, which promises orders-of-magnitude improvement in mapping speed over its predecessors. PRIMA will field exquisitely sensitive kilopixel arrays of kinetic inductance detectors (KIDs) for the Far-Infrared Enhanced Survey Spectrometer (FIRESS) instrument. PRIMA will orbit in space at the Sun-Earth L2 point, where Planck found the energetic particle flux to be about 300/min/cm2. Thus, the possible effect of a high fluence of energetic particles on the detector sensitivity must be characterized. Previous work has suggested that bombardment of KIDs by ions can reduce the quasiparticle lifetime (Barends et. al. 2009), but the conditions of the experiment were not representative of a detector which is continuously held at sub-Kelvin temperatures in the energetic particle environment of L2 orbit. To better replicate the damage which would be produced by energetic particles in this environment, we developed a fully cryogenic irradiation experiment in which a stepper motor controls a screen which can block or reveal an alpha particle emitter. This setup can be used to irradiate aluminum KID arrays fabricated for FIRESS to well-controlled dose levels. In this work, we calculate the damage dose expected for a 5-year mission in L2 orbit, and we irradiate an array to approximately 62 percent of this level. Before and after irradiation, we measure the quasiparticle lifetimes, resonant frequencies, and quality factors of the detectors.

2605.00151 2026-05-04 math.DG math.MG math.SP

Lipschitz rigidity for scalar curvature on singular manifolds in odd dimensions

标量曲率在奇数维奇异流形上的Lipschitz刚性

Lukas Schoenlinner

AI总结 本文研究标量曲率在奇数维奇异流形上的Lipschitz刚性,结合谱流论证和抽象锥算子分析,证明了奇数维Riemannian spin流形的刚性结果。

Comments 40 pages

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AI中文摘要

本文的主要成果是在奇数维Riemannian spin流形上,针对具有锥状奇点的标量曲率提出了一种Llarull型刚性陈述。偶维情况由与Simone Cecchini、Bernhard Hanke和Thomas Schick合作的先前工作通过索引理论和抽象锥算子分析解决。本文扩展了抽象锥算子的分析,将其应用于奇异流形上的扭曲Dirac算子,并结合谱流论证来证明主要结果。

英文摘要

The main result of this article is a Llarull-type rigidity statement for scalar curvature on Riemannian spin manifolds with cone-like singularities in odd dimensions. The even dimensional analog was proven in an earlier work together with Simone Cecchini, Bernhard Hanke and Thomas Schick using index theory and the analysis of abstract cone operators, which applies to Dirac operators associated with generalized cone metrics. We will extend the analysis of abstract cone operators, apply it to twisted Dirac operators on singular manifolds and combine it with a spectral flow argument to prove the main result.

2605.00150 2026-05-04 math.SP math-ph math.MP

Negative spectrum of non-local operators with periodic potential

非局部算子与周期势的负谱

S. Pirogov, E. Zhizhina

AI总结 研究非局部算子在种群动力学中的谱分析,探讨周期性扰动对负谱的影响,证明此类扰动导致种群灭绝。

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AI中文摘要

本文研究非局部算子在种群动力学模型中的谱分析。我们考虑非局部算子的卷积类型,其负周期扰动描述了在抑制力作用下种群的演化。研究发现,任何负周期扰动都会将谱移至左半平面,从而导致任何维度下种群灭绝。

英文摘要

The paper deals with spectral analysis of non-local operators arising in population dynamics models. We consider negative periodic perturbations of non-local operators of the convolution type. Such operators describe evolutions of the first correlation function in the stochastic birth and death dynamcis in the presence of suppression forces that increase mortality. We consider the case when the birth kernel can be non-symmetric and spatially heterogeneous. It has been proven that any negative periodic perturbation of the equilibrium dynamics generator shifts the spectrum to the left half-plane and, consequently, such a perturbation of mortality leads to the population extinction in any dimension.

2605.00149 2026-05-04 physics.chem-ph

Nuclear Spin Isomers and the Pauli Principle in Polaritonic Chemistry

核自旋异构体与极子化学中的泡利原理

Csaba Fábri, Gábor J. Halász, Lorenz S. Cederbaum, Ágnes Vibók

AI总结 研究核自旋异构体与泡利原理在极子化学中的影响,通过数值模拟和分析模型展示集体光-物质耦合的重塑作用。

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AI中文摘要

泡利原理在量子物理中有深远影响。本文首次探讨其与核自旋异构体在极子化学中的联合影响。我们首先在红外腔中对两个$^{14}$NH$_3$分子的正交和反向自旋异构体进行精确数值描述,然后通过分析模型推广这些结果。我们的发现无疑表明,泡利原理和核自旋异构体显著重塑集体光-物质耦合。

英文摘要

The Pauli principle has far-reaching consequences in quantum physics. Here, we investigate, for the first time, its implications, together with nuclear spin isomerism, in polaritonic chemistry. We first present an accurate numerical description in a realistic situation of two $^{14}$NH$_3$ molecules, existing as ortho and para spin isomers, in an infrared cavity. Then, we generalize these results using an analytical model for molecular ensembles. Our findings undoubtedly demonstrate that the Pauli principle and nuclear spin isomerism significantly reshape collective light-matter coupling.

2605.00148 2026-05-04 math.PR math-ph math.MP

Persistence in perturbed contact models in continuum

连续空间中受扰接触模型的持久性

S. Pirogov, E Zhizhina

AI总结 本文研究了在无临界条件下的接触模型中局部灾难是否会导致灭绝,通过非局部卷积型算子扰动证明了存在不变测度。

Comments arXiv admin note: substantial text overlap with arXiv:2304.14237

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AI中文摘要

局部灾难是否会导致灭绝?本文对此进行了回答。在论文\cite{PZ-PPI}中,我们考虑了在局部紧度量空间上的接触过程,具有状态依赖的出生和死亡率,并制定了确保存在不变测度的充分条件。\cite{PZ-PPI}中的一个关键条件是临界 regime 条件,这意味着在平均上存在出生和死亡率之间的平衡。在本文中,我们拒绝临界性条件,并假定平衡条件被违反。这表明,在考虑的接触模型中,相关函数的演变由一个受负势扰动的非局部卷积型算子决定。我们证明局部峰值的死亡率通常不会导致灭绝。即使没有临界性条件,我们证明了一族不变测度的存在,这些测度可以使用费曼-卡茨公式来描述。

英文摘要

Can a local disaster lead to extinction? We answer this question in this work. In the paper \cite{PZ-PPI} we considered contact processes on locally compact metric spaces with state dependent birth and death rates and formulated sufficient conditions on the rates that ensure the existence of invariant measures. One of the crucial conditions in \cite{PZ-PPI} was the critical regime condition, which meant the existence of a balance between birth and death rates in average. In the present work, we reject the criticality condition and suppose that the balance condition is violated. This implies that the evolution of the correlation functions of the contact model under consideration is determined by a nonlocal convolution type operator perturbed by a (negative) potential. We show that local peaks in mortality do not typically lead to extinction. We prove that a family of invariant measures exists even without the criticality condition and these measures can be described using the Feynman-Kac formula.

2605.00145 2026-05-04 nlin.CD

Critical parameters of an oval billiard with an elliptical component

椭圆弹奏板中关键参数的临界值

Anne Kétri P. da Fonseca, Joelson D. V. Hermes, Edson D. Leonel

AI总结 研究椭圆与卵形变形结合的弹奏板中从可积到混沌转变的关键参数,发现椭圆成分的存在引入第二个变形轴,并通过数值验证证明椭圆成分降低全局混沌阈值,揭示不同边界变形对相空间组织的影响。

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AI中文摘要

我们探讨了一种结合椭圆和卵形变形的弹奏板家族中从可积到混沌转变的关键参数。不同于标准卵形弹奏板,其中已知的关键参数控制最后不变曲线的破坏,引入可积椭圆成分引入了第二个变形轴。我们推导出该联合系统的临界参数的解析表达式,并通过Slater定理数值验证,证明增加椭圆成分会降低全局混沌的临界阈值。此外,我们发现了一个此前未探索的区域:当两个变形成分处于相位一致时,椭圆贡献会逐步抑制混沌,导致不变曲线和周期轨道的恢复。一种一阶解析近似证实了这种行为,通过数值验证加以支持。我们的结果揭示了不同边界变形之间相互作用如何丰富相空间组织,并为弹奏板系统中混沌动力学的增强可控性提供新的见解。

英文摘要

We explore the critical parameters responsible for the transition from integrability to chaos in a family of billiards combining elliptical and oval deformations. Unlike standard oval billiards, where a known critical parameter governs the destruction of the last invariant curve, the introduction of an integrable elliptic component yields a second deformation axis. We derive an analytical expression for the critical parameter in this combined system and validate it numerically using Slater's theorem, showing that increasing the elliptical component lowers the critical threshold for global chaos. Moreover, we uncover a previously unexplored regime: when the two deformation components are in phase, the elliptic contribution progressively suppresses chaos, leading to the restoration of invariant curves and periodic orbits. A first-order analytical approximation confirms this behavior, supported by numerical validation. Our results reveal how the interplay between distinct boundary deformations enriches phase-space organization and offers enhanced controllability of chaotic dynamics in billiard systems.

2605.00144 2026-05-04 physics.med-ph physics.bio-ph

Model-aided quantification of patient-specific benefit in mitigating radiation induced lymphopenia by particle therapy of cancer

基于模型的患者特异性获益量化研究:通过癌症粒子治疗缓解辐射诱导淋巴减少

Vladislav Sandul, Marco Durante, Thomas Friedrich

AI总结 本文提出一个生物动力学模型,用于量化放射治疗中淋巴细胞减少及恢复过程,通过整合辐射剂量体积分布、血液循环动力学及不同恢复速率的淋巴细胞群体动力学,预测个体淋巴减少严重程度,并展示粒子治疗相比光子治疗可减少约30%的淋巴细胞减少。

Comments 27 pages, 4 figures

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AI中文摘要

治疗相关淋巴减少是癌症治疗中常见且临床意义重大的后果,可能影响免疫介导的肿瘤控制并恶化患者预后。尽管其重要性,目前尚无机制框架能准确从患者特异性数据预测淋巴减少的严重程度。本文提出一个生物动力学模型,定量描述放疗过程中及之后的淋巴细胞耗尽与恢复,整合辐射剂量体积分布、血液循环动力学及快速和慢速恢复的淋巴细胞群体动力学。该模型利用56个独立的临床数据集进行校准和验证,涵盖各种肿瘤部位和治疗模式。模型能再现观察到的淋巴细胞计数,并能从基线或早期治疗计数预测个体淋巴减少的严重程度。应用该框架,我们证明粒子治疗相比光子治疗可减少约30%的淋巴细胞耗尽,提供了其观察到的免疫保护益处的定量解释。通过将辐射物理、免疫动力学和临床结果联系起来,该模型建立了基于机制的预测方法,以预测系统性免疫毒性。除了放疗外,该框架还提供了一种可推广的策略,用于将早期生物标志物整合到治疗优化中,推动个性化和免疫保护的癌症治疗。

英文摘要

Treatment-related lymphopenia is a frequent and clinically significant consequence of cancer therapy that can compromise immune-mediated tumor control and worsen patient outcomes. Despite its importance, no mechanistic framework exists to accurately predict the severity of lymphopenia from patient-specific data. Here, we present a biokinetic model that quantitatively describes lymphocyte depletion and recovery during and after radiotherapy, integrating radiation dose-volume distributions, blood circulation dynamics, and distinct kinetics of fast- and slow-recovering lymphocyte populations. The model was calibrated and validated using 56 independent clinical datasets encompassing various tumor sites and treatment modalities. It reproduces observed lymphocyte counts and enables prediction of individual severity of lymphopenia from baseline or early-treatment counts. Applying this framework, we demonstrate that particle therapy reduces lymphocyte depletion by ~30% compared with photon therapy, providing a quantitative explanation for its observed immune-sparing benefit. By linking radiation physics, immune kinetics, and clinical outcomes, our model establishes a mechanistically grounded predictive approach for anticipating systemic immune toxicity. Beyond radiotherapy, this framework offers a generalizable strategy for integrating early biological markers into treatment optimization, advancing personalized and immune-preserving cancer therapy.