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2606.12408 2026-06-11 hep-ph astro-ph.CO 新提交

When direct detection constrains reheating temperature: freeze-in with stronger couplings and inflaton-seeded freeze-in

当直接探测约束再加热温度:具有更强耦合的冻结产生和暴胀子播种的冻结产生

Xavier Bertou, Olivier Deligny, Mathieu Gross, Yann Mambrini, Issam-Eddine Mellouki

AI总结 本文分析DAMIC-M和PandaX实验对更强耦合或非热源(如暴胀子衰变)的冻结产生模型中再加热温度的约束,并找到在避免电子散射截面实验限制下正确重现暗物质遗迹密度的可行方案。

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AI中文摘要

DAMIC-M和PandaX合作组的最新结果已经排除了在标准模型扩展中引入额外超轻$U(1)_{\rm X}$规范玻色子的情况下,质量范围$3~\mathrm{MeV} \lesssim m_\chi \lesssim 1~\mathrm{GeV}$内的标准冻结产生暗物质。在这项工作中,我们分析了DAMIC-M和PandaX结果对更强耦合冻结产生模型中再加热温度的约束,或者当非热源(如暴胀子衰变)发挥作用时的情况。我们识别了可行的情景,在这些情景中,暗物质遗迹丰度被正确重现,同时规避了当前对电子散射截面$\overline{\sigma}_\mathrm{e}$的实验限制。特别地,我们表明,对于低于电弱尺度的再加热温度,玻尔兹曼抑制的产生可以通过更强的耦合来补偿,使冻结产生情景处于当前实验可及范围内。最后,我们研究了一种混合情景,其中暴胀子衰变的一个小分支比播种了非零的初始暗物质丰度。我们表明,这种贡献可以显著改变广泛参数空间中的冻结产生预测,为探测极弱相互作用提供了额外途径。

英文摘要

Recent results from the DAMIC-M and PandaX collaborations have excluded the standard freeze-in production of dark matter for masses in the range $3~\mathrm{MeV} \lesssim m_χ\lesssim 1~\mathrm{GeV}$ in the context of extensions of the Standard Model featuring an additional ultra-light $U(1)_{\rm X}$ gauge boson. In this work, we analyze the constraints induced by DAMIC-M and PandaX results on the reheating temperature in freeze-in models at stronger coupling, or when a non-thermal source (such as inflaton decay) comes into play. We identify viable scenarios in which the DM relic abundance is correctly reproduced while evading current experimental bounds on the electron-scattering cross section, $\overlineσ_\mathrm{e}$. In particular, we show that for reheating temperatures below the electroweak scale, Boltzmann suppressed production can be compensated by stronger couplings, bringing freeze-in scenarios within present experimental reach. Finally, we study a hybrid scenario in which a small branching ratio of inflaton decay seeds a nonzero initial dark-matter abundance. We show that such contributions can significantly modify freeze-in predictions across broad regions of parameter space, offering an additional pathway for probing extremely feeble interactions.

2606.12405 2026-06-11 astro-ph.CO 新提交

Bounding the Effect of HOD Assumptions on Small-Scale Clustering Constraints

HOD假设对小尺度成团约束的影响界限

Nick Magnelli, Zachery Brown, Lado Samushia

AI总结 利用AbacusSummit模拟的LRG星系目录,量化HOD模型假设对小尺度成团约束的影响,发现保守与乐观HOD先验下排除的宇宙学比例差异显著(25% vs 81%),表明强约束需信息性星系-暗晕先验。

Comments 22 pages, 15 figures

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AI中文摘要

小尺度星系成团预计包含大量宇宙学信息,但这些信息在多大程度上独立于假定的星系-暗晕联系来约束基于暗晕的宇宙学仍不清楚。我们使用从{\tt \textsc{AbacusSummit}}套件中81个宇宙学构建的类LRG模拟星系目录量化这种依赖性。我们分析了从$5$到$80$ Mpc/$h$尺度上的两点相关函数多极矩,并比较了标准五参数HOD模型的两种极限处理:\enquote{下限}和\enquote{上限}。在保守的下限情形中,我们仅施加宽泛的初始HOD边界,并对HOD参数进行轮廓化以确定可用的最小约束能力;我们通过{\tt HODmin}实现这一点,这是一个为在HOD空间中最小化$\chi^2$而编写的两阶段全局优化算法。在乐观的上限情形中,我们假设HOD参数完全已知。我们发现,在相同的建模假设下,与相同的Planck $\Lambda$CDM模拟数据向量比较时,下限和上限之间存在显著差异:对于下限,测试的离散{\tt \textsc{AbacusSummit}}宇宙学中有$25\\%$在$3\sigma$水平被排除,而对于上限,约$81\\%$被排除。许多宇宙学在下限中与数据吻合良好,但在上限中却被$\chi^2$多个数量级排除。因此,我们观察到小尺度成团约束的强度在很大程度上取决于假设的HOD先验信息量。我们比较了这种效应对各种选择的敏感性,如尺度截断、角度截断、多极矩包含、模拟相位和模拟HOD模型。我们宽泛的下限-上限区间表明,信息性星系-暗晕先验对于提取强小尺度成团约束是必要的。

英文摘要

Small-scale galaxy clustering is expected to contain substantial cosmological information, but the extent to which this information constrains halo-based cosmologies independent of an assumed galaxy--halo connection remains unclear. We quantify this dependence using LRG-like mock galaxy catalogs built from 81 cosmologies in the {\tt \textsc{AbacusSummit}} suite. We analyze two-point correlation function multipoles on scales ranging from $5$--$80$ Mpc/$h$ and compare two limiting treatments, the \enquote{floor} and \enquote{ceiling}, of the standard five-parameter HOD model. In the conservative floor case, we impose only broad initial HOD bounds and profile over HOD parameters to determine the minimum constraining power available; we accomplish this with {\tt HODmin}, a two-stage global optimization algorithm written for minimizing $χ^2$ in HOD space. In the optimistic ceiling case, we assume the HOD parameters are known exactly. We find a significant difference between the floor and ceiling when comparing against the same Planck $Λ$CDM mock data vector with identical modeling assumptions: for the floor, $25\%$ of the discrete {\tt \textsc{AbacusSummit}} cosmologies tested are excluded at $3σ$, whereas for the ceiling, $\sim81\%$ are excluded. Many cosmologies agree well with data in the floor, and yet in the ceiling are excluded by multiple orders of magnitude in $χ^2$. We therefore observe the strength of small-scale clustering constraints depends heavily on the amount of prior HOD information assumed. We compare the sensitivity of this effect to various choices like scale cut, angle cut, multipole inclusion, mock phase, and mock HOD model. Our wide floor--ceiling bracket indicates that informative galaxy--halo priors are necessary for extracting strong small-scale clustering constraints.

2606.12404 2026-06-11 hep-ph astro-ph.HE quant-ph 新提交

Collective neutrino oscillations: Many-body non-forward effects and non-classicality

集体中微子振荡:多体非前向效应与非经典性

Julien Froustey, Ermal Rrapaj, Yuhao Liu, Gushu Li, Costin Iancu, Vincenzo Cirigliano

AI总结 研究密集天体环境中中微子演化的多体非前向散射效应,通过量子动力学与完整多体哈密顿量对比,揭示时间尺度和渐近行为差异,并分析量子计算资源需求。

Comments 25 pages, 12 figures

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AI中文摘要

密集天体环境中中微子演化通常用量子动力学框架描述(忽略多体关联积累),或通过简化多体计算(允许显著纠缠发展)。本文在简单中微子气体构型中比较这两种方法,特别强调非前向散射过程的作用。这些效应通过动力学描述中的碰撞项或考虑完整的中微子-中微子多体哈密顿量纳入。我们突出两种描述在特征时间尺度和渐近行为上的差异。受量子计算天然适合多体计算的启发,我们进一步研究中微子演化的非经典性,讨论Trotter误差缩放,以及构建量子电路在纠缠门和非Clifford门方面的相关成本。我们发现,中微子多体演化所需的资源在典型高能物理问题中处于低端,而在量子化学问题中处于中高端。对于完整哈密顿量,资源需求相对于截断版本增加。我们强调高效费米子到量子比特编码的重要性,这对于减少此类模拟所需的大量计算资源至关重要。

英文摘要

Neutrino evolution in dense astrophysical environments is typically described either within a quantum kinetic framework, which neglects the build-up of multi-body correlations, or through simplified many-body calculations that allow significant entanglement to develop. In this work, we compare these two approaches in a simple neutrino-gas configuration, with particular emphasis on the role of non-forward scattering processes. These effects are incorporated either through a collision term in the kinetic description, or by considering the full neutrino-neutrino many-body Hamiltonian. We highlight differences between the two descriptions in both their characteristic timescales and asymptotic behavior. Motivated by the natural suitability of quantum computing for many-body calculations, we further investigate the non-classicality of neutrino evolution, discussing Trotter error scaling, along with the associated costs of constructing quantum circuits in terms of entangling gates and non-Clifford gates. We find that the resources needed for neutrino many-body evolution are on the low end of typical high-energy physics problems and on the mid to high end with respect to quantum chemistry problems. For the full Hamiltonian, resource requirements increase relative to the truncated version. We emphasize the importance of efficient fermion-to-qubit encodings, which are essential for reducing the substantial computational resources required for such simulations.

2606.12401 2026-06-11 astro-ph.EP 新提交

The carbon isotope ratio of β Pic b with high-resolution spectroscopy

利用高分辨率光谱测量β Pic b的碳同位素比

D. González Picos, I. A. G. Snellen, R. Landman, S. de Regt, N. Grasser, J. L. Birkby, T. Stolker, I. Koutalios, M. A. Kenworthy

AI总结 通过CRIRES+高分辨率光谱测量年轻超级木星β Pic b的$^{12}C/^{13}C$比值为$58^{+18}_{-15}$,与当前星际介质一致,低于太阳值,并约束了大气参数和云层性质。

Comments Accepted to A&A

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AI中文摘要

同位素比值追踪行星的形成和演化,并将其大气与原生原行星盘的化学性质联系起来。我们利用甚大望远镜(VLT)上CRIRES+的K波段光谱($\mathcal{R} \approx 100{,}000$)在11个夜晚测量了年轻超级木星$\beta$ Pic b大气中的$^{12}\mathrm{C}/^{13}\mathrm{C} = 58^{+18}_{-15}$。我们探测到$^{12}\mathrm{CO}$和$^{13}\mathrm{CO}$,并通过贝叶斯反演与近红外测光联合拟合约束了$^{12}\mathrm{C}/^{13}\mathrm{C}$。推断的$^{12}\mathrm{C}/^{13}\mathrm{C}$与当前星际介质(ISM)一致,低于太阳值,并与其他年轻超级木星的测量结果相当。我们还反演得到$T_{\rm eff} = 1629^{+30}_{-28}\\,\mathrm{K}$,近太阳至略超太阳的金属丰度([M/H]$ = 0.20^{+0.16}_{-0.12}$),类太阳的碳氧比(C/O$ = 0.52 \pm 0.03$),以及厚云的初步证据。我们独立分析每个夜晚,并合并信噪比(S/N)最高的六个历元的结果,将夜与夜之间的散射传播到最终不确定度中。这为位于CO雪线内的直接成像行星提供了一个同位素基准。

英文摘要

Isotopic ratios trace the formation and evolution of planets and link their atmospheres to the chemistry of their natal protoplanetary discs. We measure $^{12}\mathrm{C}/^{13}\mathrm{C} = 58^{+18}_{-15}$ in the atmosphere of the young super-Jupiter $β$ Pic b from 11 nights of CRIRES+ K-band spectroscopy ($\mathcal{R} \approx 100{,}000$) at the Very Large Telescope (VLT). We detect both $^{12}\mathrm{CO}$ and $^{13}\mathrm{CO}$ and constrain $^{12}\mathrm{C}/^{13}\mathrm{C}$ with a Bayesian retrieval jointly fitted with near-infrared photometry. The inferred $^{12}\mathrm{C}/^{13}\mathrm{C}$ is consistent with the present-day interstellar medium (ISM), is below the solar value, and is comparable to measurements in other young super-Jupiters. We also retrieve $T_{\rm eff} = 1629^{+30}_{-28}\,\mathrm{K}$, near-solar to mildly super-solar metallicity ([M/H]$ = 0.20^{+0.16}_{-0.12}$), a solar-like carbon-to-oxygen ratio (C/O$ = 0.52 \pm 0.03$), and tentative evidence for thick clouds. We analyse each night independently and combine the results of the six epochs with the highest signal-to-noise ratio (S/N), propagating night-to-night scatter into the final uncertainties. This provides an isotopic benchmark for a directly imaged planet interior to the CO snow line.

2606.12399 2026-06-11 physics.soc-ph 新提交

Revealing Peri-Urban Dislocation through Percolation Analysis

通过渗流分析揭示城郊错位

Dr Melissa Barrientos-Trinanes, Professor Stephen Marshall, Professor Elsa Arcaute

AI总结 提出城郊错位作为结构性条件,利用街道网络渗流分析揭示城市核心与外围的层级错位,并通过智利瓦尔迪维亚和美国波士顿案例展示两种不同表现。

Comments 17 pages, 5 figures

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AI中文摘要

本文引入城郊错位作为一种结构性条件,通过捕捉内城与外围区域之间的层级错位,补充了现有的蔓延度量指标。传统度量强调密度、土地利用混合度或碎片化,而城郊错位反映了城市系统核心-外围关系功能组织中更深层次的分歧。我们利用街道网络的渗流分析来操作化这一概念,通过聚类图和树状图揭示层级模式,提供城市元素之间的关系结构。两个案例研究——智利瓦尔迪维亚和美国波士顿——展示了对比鲜明的表现:瓦尔迪维亚的结构性逆转,其中同质化的居住外围主导了层级聚类过程;以及波士顿的城郊空洞,尽管大都市整合,孤立的细分地块仍然存在。这些发现将城郊错位定位为一种与蔓延相关但区别于基于密度或外围性度量的结构维度;它可能独立发生,或代表蔓延先前未被识别的结构特征。在方法论上,我们应用成熟的渗流技术来揭示这一先前未被阐述的结构现象,从而能够检测城市系统内的层级错位。在概念上,我们引入城郊错位作为城市结构的一个新维度,通过复杂性视角帮助阐明关于蔓延和城郊化的辩论,并实现跨不同城市背景的核心-外围诊断。

英文摘要

This paper introduces peri urban dislocation as a structural condition that complements existing sprawl metrics by capturing hierarchical misalignments between inner city and peripheral areas. Whereas conventional measures emphasise density, land-use mix, or fragmentation, peri-urban dislocation reflects deeper divergences in the core periphery relational functional organisation of urban systems. We operationalise this concept using percolation analysis of street networks, revealing hierarchical patterns via clustering maps and dendrograms, providing a relational structure between urban elements. Two case studies, Valdivia, Chile, and Boston, USA, demonstrate contrasting manifestations: a structural reversal in Valdivia, where a homogeneous residential periphery dominates the hierarchical clustering process, and peri-urban voids in Boston, where isolated parcellations persist despite metropolitan consolidation. These findings position peri-urban dislocation as a structural dimension linked to sprawl yet distinct from metrics based on density or peripherality; one that may occur independently or represent a previously unidentified structural signature of sprawl. Methodologically, we apply established percolation techniques to expose this previously unarticulated structural phenomenon, enabling the detection of hierarchical misalignments within urban systems. Conceptually, we introduce peri urban dislocation as a new dimension of urban structure, helping articulate debates on sprawl and peri urbanisation through a complexity informed lens and enabling core periphery diagnostics across diverse urban contexts.

2606.12398 2026-06-11 physics.optics cond-mat.mtrl-sci 新提交

Quantifying the Distribution of Biexciton Emission Efficiencies in Colloidal Quantum Shells

胶体量子壳中双激子发射效率分布的量化

Tjom Arens, Dulanjan Harankahage, Divesh Nazar, Mikhail Zamkov, Freddy T. Rabouw

AI总结 本文提出一种串扰抑制的SPAD阵列光子关联方法,高通量量化超过1000个胶体量子壳的多光子发射,发现双激子发射效率呈近高斯分布,平均值为0.55,估计内在标准差为0.12。

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AI中文摘要

多光子发射效率是量子光源的重要特性。高亮度多光子发射适用于高功率照明和激光,而其完全抑制则是高纯度单光子产生所必需的。在胶体量子发射器中,多光子发射在不同粒子间可能存在显著差异。传统的逐粒子方法难以解决这种异质性。本文介绍了一种串扰抑制的SPAD阵列光子关联方法,用于高通量量化超过1000个胶体量子壳的多光子发射。通过将同一样品的两个图像投影到探测器阵列的远距离区域,我们避免了探测器像素间的短程串扰。时间门控抑制了暗计数符合,并区分了单个发射体与团簇。将该方法应用于量子壳,揭示了双激子发射效率的近高斯分布,平均值为0.55,估计内在标准差为0.12。双激子效率与粒子亮度的批次内相关性与俄歇猝灭的体积标度一致。这些结果确立了SPAD阵列光子关联作为解决纳米粒子集合中多光子异质性的可扩展途径。

英文摘要

The efficiency of multi-photon emission is an important characteristic of quantum light sources. Bright multi-photon emission is desirable for high-power lighting and lasers, while its complete suppression is required for high-purity single-photon generation. In colloidal quantum emitters, multi-photon emission can vary significantly between individual particles. Resolving this heterogeneity remains challenging with conventional particle-by-particle approaches. Here, we introduce a crosstalk-suppressed SPAD-array photon-correlation approach for high-throughput quantification of multi-photon emission from more than 1000 colloidal quantum shells. By projecting two images of the same sample onto distant regions of the detector array, we avoid short-range crosstalk between detector pixels. Time gating suppresses dark-count coincidences and distinguishes individual emitters from clusters. Applying this method to quantum shells reveals a near-Gaussian distribution of biexciton emission efficiencies, with a mean of 0.55 and an estimated intrinsic standard deviation of 0.12. Intra-batch correlations between the biexciton efficiency and the particle brightness are consistent with the volume scaling of Auger quenching. These results establish SPAD-array photon correlation as a scalable route to resolve multi-photon heterogeneities in nanoparticle ensembles.

2606.12394 2026-06-11 quant-ph 新提交

Scaling-optimal purification of noisy qubit unitary channels

噪声量子比特酉通道的缩放最优纯化

Ryotaro Niwa, Satoshi Yoshida, Koki Ono, Takeru Utsumi, Zhaoyi Li, Yuxiang Yang, Ryuji Takagi, Mio Murao

AI总结 针对带噪声的量子比特酉通道,提出基于纠缠辅助量子纠错码的U(2)-协变并行协议,实现噪声强度O(1/n)抑制,并证明在低噪声区域渐近最优。

Comments 6+9 pages, 2 figures

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AI中文摘要

我们考虑纯化噪声量子比特酉通道的问题。给定应用未知量子比特酉通道后跟随去极化噪声的能力,我们旨在构建一个超通道,将噪声酉纯化回原始未知酉。我们首先提供数值证据,表明当通道使用次数有限时,顺序策略可以严格优于并行策略,突出了与状态纯化的根本区别。然后,我们基于一种新颖的纠缠辅助量子纠错码,提供了一个具体的$\mathrm{U}(2)$-协变并行协议,该协议将一阶噪声强度抑制为$O(1/n)$,其中$n$为通道使用次数,并证明在低噪声区域,即使允许顺序策略,这种缩放也是渐近最优的。

英文摘要

We consider the problem of purifying noisy qubit unitary channels. Given the ability to apply an unknown qubit unitary channel followed by depolarizing noise, we aim to construct a superchannel that purifies the noisy unitary back to the original unknown unitary. We first provide numerical evidence that sequential strategies can strictly outperform parallel strategies when the number of channel uses is finite, highlighting the fundamental distinction from state purification. We then provide a concrete $\mathrm{U}(2)$-covariant parallel protocol based on a novel entanglement-assisted quantum error-correcting code that suppresses the first-order noise strength as $O(1/n)$ with $n$ channel uses and show this scaling is asymptotically optimal in the low-noise regime, even when sequential strategies are allowed.

2606.12393 2026-06-11 hep-ph hep-th physics.data-an 新提交

The Fundaments of Unity: ${\mathcal O}(1)$ Couplings in Quantum Field Theories

统一的基础:量子场论中的 ${\mathcal O}(1)$ 耦合

Ben Allanach

AI总结 本文批判性地检验了基本量子场论中无量纲耦合应为量级1的预期,提出用展宽(最大与最小耦合模之比)量化该特性,并发现即使耦合服从独立同分布,比值可能远大于预期。

Comments 15 pages, 3 figures

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AI中文摘要

我们批判性地检验了在基本量子场论中,拉格朗日密度中的无量纲耦合应全部为量级1的预期。我们提出了一种衡量理论符合该预期的度量:展宽(此类无量纲耦合的模的最大值与最小值之比),并得到了各种闭式结果。如果我们采用独立同分布(IID)耦合来参数化对量级1耦合值的不确定性,则耦合的比值可能远大于朴素预期。例如,对于一个具有20个IID单位正态耦合的理论,其中两个耦合的模之比大于100的概率为0.29。即使IID耦合具有指数抑制的尾部,量级1耦合的比值分布也具有肥大的幂律尾部,且随独立耦合数量的增加而增长。

英文摘要

We critically examine the expectation that in a fundamental quantum field theory, dimensionless couplings in the Lagrangian density should all be of order unity. We propose a measure to quantify the adherence of a theory to this: the spread (the ratio of the largest to the smallest of the magnitudes) of such dimensionless couplings, obtaining various closed-form results. If we take independent identically distributed (IID) couplings to parameterise our uncertainty on the values of the order unity couplings, ratios of couplings can be much larger than one might naively expect. For a theory with 20 IID unit normal couplings, the probability that the magnitude of the ratio of two of them is greater than 100 is 0.29, for example. Even when the IID couplings have exponentially suppressed tails, the distribution of ratios of order one couplings has fat power-law tails which grow with the number of independent couplings.

2606.12391 2026-06-11 physics.plasm-ph physics.space-ph 新提交

Secondary drift-driven instabilities in the presence of a parallel-propagating electromagnetic ion cyclotron wave and cold multi-component ions

平行传播电磁离子回旋波与冷多组分离子存在下的次级漂移驱动不稳定性

Opal Issan, Patrick Kilian, Vadim Roytershteyn, Salomon Janhunen, Gian Luca Delzanno

AI总结 通过全动力学粒子模拟和线性理论,研究平行传播EMIC波驱动的次级不稳定性对冷等离子体的影响,发现次级波在低振幅下仍存在,并导致冷质子和氧离子的各向异性加热。

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AI中文摘要

电磁离子回旋(EMIC)波在地球内磁层中常见,尤其在环电流质子各向异性驱动的地磁暴期间。虽然它们在辐射带热离子散射中的作用已明确,但与冷(<100 eV)等离子体的相互作用仍知之甚少,部分原因是航天器充电阻碍冷离子到达仪器。已知平行传播EMIC波的电场可驱动种间垂直极化漂移,激发低混杂次级不稳定性。在多组分等离子体中,这些包括修正双流和离子-离子交叉场不稳定性。本文通过全动力学粒子模拟和线性理论,研究此类次级不稳定性对平行传播EMIC波和多组分等离子体的影响。我们发现,只要冷种群足够冷,次级波即使在低EMIC振幅下也存在。动力学模拟表明,这些次级模式产生冷质子和单电荷氧离子的各向异性加热,主要垂直于环境磁场方向,而电子则在平行和垂直方向均被加热。

英文摘要

Electromagnetic ion cyclotron (EMIC) waves are commonly observed in Earth's inner magnetosphere, particularly during geomagnetic storms driven by anisotropic ring-current protons. While their role in radiation belt scattering of hot ions is well established, their interaction with the cold (less than 100 eV) plasma remains less understood. This is partly due to limited magnetospheric cold ion observations, as spacecraft charging can prevent cold ions from reaching onboard instruments. It is well-known that the electric field of a parallel-propagating EMIC wave can drive inter-species perpendicular polarization drifts that excite lower-hybrid secondary instabilities. In multi-component plasmas, these include the modified two-stream and the ion-ion cross-field instabilities. In this paper, we study the impact of such secondary instabilities on the parallel-propagating EMIC wave and multi-component plasma via a fully kinetic particle-in-cell simulation and linear theory. We find that the secondary waves persist even at low EMIC amplitudes, provided the cold population remains sufficiently cold. The kinetic simulation demonstrates that these secondary modes produce anisotropic heating of cold protons and singly-charged oxygen ions, primarily in the direction perpendicular to the ambient magnetic field and of electrons in both parallel and perpendicular directions.

2606.12390 2026-06-11 astro-ph.HE 新提交

Time-dependent cosmic-ray escape from wind bubbles: hard spectra formation

从风泡中时间依赖的宇宙射线逃逸:硬谱形成

Lukas Merten, Sophie Aerdker, Enrico Peretti

AI总结 研究风泡中宇宙射线的时间依赖逃逸,通过求解含时输运方程发现逃逸谱可硬于E^{-2},且低能粒子可能被显著抑制,为多信使观测提供特征。

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AI中文摘要

概述:风驱动气泡是动态系统,根据其物理性质,可将宇宙射线加速到非常高的能量。我们研究粒子输运的时间依赖描述如何影响逃逸的宇宙射线通量。模型:风泡系统建模为球对称。宇宙射线在终止激波位置连续注入,通过对流和扩散传播,直到在作为自由逃逸边界的前向激波的时间依赖位置逃逸。方法:将一维球对称含时输运方程转化为相应的随机微分方程组,并使用开源宇宙射线传播框架CRPropa的修改版本进行积分。结果:我们发现,在风驱动阶段,风泡下游逃逸谱可以比扩散激波加速的传统预期$\sim E^{-2}$更硬。根据湍流模型,初始能谱在最低能量处可能被显著抑制,这可能是区分不同湍流实现的可观测特征。这种效应可能导致低能粒子的有效约束,从而在多信使辐射和气泡内累积的宇宙射线grammage方面产生可观测的影响。

英文摘要

Overview: Wind-driven bubbles are dynamic systems that can accelerate cosmic rays, depending on their physical properties, up to very high energies. We investigate how a time-dependent description of the particle transport may impact the escaping cosmic-ray flux. Model: The wind bubble system is modeled as spherically symmetric. Cosmic rays are continuously injected at the position of the termination shock and propagate through advection and diffusion until the escape at the time-dependent position of the forward shock, which is treated as a free escape boundary. Methods: The one-dimensional spherical time-dependent transport equation is solved by transforming it into the corresponding set of stochastic differential equations, and integrated with a modified version of the open source cosmic-ray propagation framework CRPropa. Results: We find that, during the wind driven phase, the downstream escaping spectra from wind bubbles can be harder than $\sim E^{-2}$, the conventional expectation from diffusive shock acceleration. Depending on the turbulence model the initial energy spectrum can be significantly suppressed at lowest energies, which could be an observable feature to distinguish between different turbulence realizations. This effect could lead to an efficient confinement of low energy particles, potentially leading to observable implication in terms of multi-messenger radiation and cosmic-ray accumulated grammage within the bubble.

2606.12389 2026-06-11 astro-ph.CO 新提交

KiDS-Legacy: Joint analysis of second- and third-order cosmic shear

KiDS-Legacy:二阶和三阶宇宙剪切联合分析

L. Linke, L. Porth, P. Burger, J. Harnois-Déraps, S. Heydenreich, P. Schneider, M. Asgari, M. Bilicki, C. Georgiou, C. Heymans, H. Hildebrandt, H. Hoekstra, P. Jalan, B. Joachimi, S. Joudaki, K. Kuijken, S. Li, L. Moscardini, M. Radovich, R. Reischke, B. Stölzner, A. H. Wright, Z. Yan, Y. -H. Zhang

AI总结 联合分析KiDS巡天的二阶和三阶宇宙剪切,使用COSEBIs和三阶孔径质量矩,显著收紧Ω_m约束并将Ω_m-S_8平面品质因子提高两倍以上。

Comments 14 pages plus appendix, 15 figures, submitted to A&A

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AI中文摘要

大尺度结构的弱引力透镜效应是一个强大的宇宙学探针。虽然大多数分析依赖于二阶相关,但这些主要对参数组合$S_8 = \sigma_8 (\Omega_m/0.3)^{0.5}$敏感,限制了它们独立约束$\Omega_m$和其他宇宙学参数的能力。高阶统计量捕捉密度场的非高斯特征,因此可以打破参数简并,从弱引力透镜巡天中提取更多宇宙学信息。我们展示了Kilo-Degree巡天最终数据发布(KiDS-Legacy)中二阶和三阶宇宙剪切的联合分析。我们将2'到300'尺度上的COSEBIs(完备正交E/B模积分集)与4'到32'尺度上的三阶孔径质量矩相结合,进行二阶和三阶统计量的联合分析。与之前的KiDS分析相比,我们实现了若干方法论上的进步:具有红移和质量依赖的内禀对齐模型、在多个流体动力学模拟上验证的重子修正模型,以及减切和源聚集的修正。在KiDS-Legacy中结合COSEBIs与三阶孔径质量统计得到$\Omega_m = 0.297^{+0.056}_{-0.040}$和$S_8 = 0.806^{+0.025}_{-0.023}$,显著收紧了$\Omega_m$约束,并且与仅两点分析相比,在$\Omega_m$-$S_8$平面上的品质因子提高了一倍以上。三阶测量通过了严格的内部一致性检验,与KiDS-Legacy两点约束、其他2+3点透镜结果以及普朗克CMB测量在$1\sigma$内完全一致,没有提供$S_8$张力的证据,并展示了三点宇宙剪切作为即将进行的巡天关键探针的成熟性。

英文摘要

Weak lensing by large-scale structure is a powerful cosmological probe. While most analyses rely on second-order correlations, these are primarily sensitive to the parameter combination $S_8 = σ_8 (Ω_m/0.3)^{0.5}$, limiting their ability to constrain $Ω_m$ and other cosmological parameters independently. Higher-order statistics capture non-Gaussian features of the density field and can therefore break parameter degeneracies and extract more cosmological information from weak lensing surveys. We present a joint analysis of second- and third-order cosmic shear in the final data release of the Kilo-Degree Survey (KiDS-Legacy). We combine COSEBIs (Complete Orthogonal Sets of E-/B-mode Integrals) at scales between 2' and 300' with third-order aperture mass moments at scales between 4' and 32' to perform a joint analysis of second- and third-order statistics. Compared to previous KiDS analyses, we implement several methodological advances: an intrinsic alignment model with redshift and mass dependence, a baryon correction model validated on multiple hydrodynamical simulations, and corrections for reduced shear and source clustering. Combining COSEBIs with third-order aperture mass statistics in KiDS-Legacy yields $Ω_m = 0.297^{+0.056}_{-0.040}$ and $S_8 = 0.806^{+0.025}_{-0.023}$, significantly tightening the $Ω_m$ constraints and more than doubling the figure of merit in the $Ω_m$--$S_8$ plane compared to the two-point analysis alone. The third-order measurements pass stringent internal consistency tests, are fully compatible with the KiDS-Legacy 2-point constraints, other 2+3-point lensing results and with Planck CMB measurements within $1σ$, providing no evidence for an $S_8$ tension and demonstrating the maturity of 3-point cosmic shear as a key probe for forthcoming surveys.

2606.12388 2026-06-11 math.AP 新提交

Schauder-type Estimates and Log-Critical Well-posedness for the Two-Phase Muskat Problem with Surface Tension

具有表面张力的两相Muskat问题的Schauder型估计和对数临界适定性

Ke Chen, Ruilin Hu, Quoc-Hung Nguyen

AI总结 针对具有表面张力、不同黏度和密度对比的两相Muskat问题,通过推导适应对数临界尺度的Schauder型估计,证明了在任意维度下大初始数据的短时间适定性。

Comments This manuscript corresponds to one part of a study initially published on arXiv (arXiv:2407.05313). The original comprehensive preprint has been divided into a series of papers, each separately addressing the well-posedness of certain free boundary problems, the general case of the Muskat problem, and problems with fixed boundaries. The present article forms Part II of this series

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AI中文摘要

我们证明了具有表面张力的Muskat问题在全两相环境下的短时间适定性,允许不同的黏度、任意的密度对比和刚性边界。特别地,没有对密度对比施加Rayleigh-Taylor符号条件。界面被假定为图形,与固定边界均匀分离,初始数据可以在对数临界类$\dot C^{1,\log^\varkappa}\cap H^1$中很大,其中$\varkappa>1$。因此,结果达到了自然Lipschitz阈值,仅差一个对数修正。主要困难在于,在存在黏度跳跃和边界的情况下,界面方程不是由封闭的显式轮廓动力学定律给出的。相反,法向速度通过移动域中的椭圆传输问题恢复,得到的演化是一个真正的非局部拟线性方程。我们推导了适应于对数临界尺度的尖锐Schauder型估计,用于由体Darcy流生成的传输算子。这些估计识别了由表面张力产生的三阶抛物机制,并控制了界面几何与椭圆传输结构之间的非线性耦合。证明建立在本文系列第一部分\cite{CHN1}中发展的Schauder框架之上,但需要对移动域中的Muskat传输问题进行新的分析。将这一椭圆理论与轮廓公式以及时间加权Hölder估计相结合,我们得到了任意维度下大界面的存在性、唯一性、光滑性和稳定性。

英文摘要

We prove short-time well-posedness for the Muskat problem with surface tension in the full two-phase setting, allowing different viscosities, arbitrary density contrast, and rigid boundaries. In particular, no Rayleigh--Taylor sign condition on the density contrast is imposed. The interface is assumed to be a graph, uniformly separated from the fixed boundaries, and the initial data may be large in the log-critical class $\dot C^{1,\log^\varkappa}\cap H^1$, with $\varkappa>1$. Thus the result reaches the natural Lipschitz threshold up to a logarithmic correction. The main difficulty is that, in the presence of viscosity jump and boundaries, the interface equation is not given by a closed explicit contour dynamics law. Instead, the normal velocity is recovered through an elliptic transmission problem in moving domains, and the resulting evolution is a genuinely nonlocal quasilinear equation. We derive sharp Schauder-type estimates, adapted to the log-critical scale, for the transmission operators generated by the bulk Darcy flow. These estimates identify the third-order parabolic mechanism produced by surface tension and control the nonlinear coupling between the interface geometry and the elliptic transmission structure. The proof builds on the Schauder framework developed in Part~I of this series \cite{CHN1}, but requires a new analysis of the Muskat transmission problem in moving domains. Combining this elliptic theory with the contour formulation and time-weighted Hölder estimates, we obtain existence, uniqueness, smoothing, and stability for large interfaces in arbitrary dimension.

2606.12383 2026-06-11 quant-ph 新提交

The Simplified Stabilizer ZX-Calculus is Minimal

简化稳定子ZX-演算是极小的

Harry K. Stoltz

AI总结 通过反模型论证,证明稳定子ZX-演算中红/绿紧致结构重合规则和双代数规则相对于连接性元规则都是必要的,从而确立arXiv:1709.08903中的规则集无冗余。

Comments 15 pages

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AI中文摘要

ZX演算的稳定子片段是该理论中最重要的片段之一。密切相关的Clifford+T片段是近似通用的(arXiv:1705.11151)。此外,稳定子演算可以用一小部分重写规则描述,其中大多数已被证明是必要的(arXiv:1709.08903)。然而,描述红/绿紧致结构重合和重要双代数定律的两条规则尚未被证明是必要的。我们提出了一个反模型风格的论证,表明这两条规则相对于Backens--Perdrix--Wang(arXiv:1709.08903)的连接性元规则都是单独必要的,从而确立了arXiv:1709.08903中提出的规则集没有冗余的重写规则。

英文摘要

The stabilizer fragment of the ZX calculus is amongst the most important fragments of the theory. The closely related Clifford+T fragment is approximately universal (arXiv:1705.11151). Additionally, the stabilizer calculus can be described by a small collection of rewrites, most of which have been shown to be necessary (arXiv:1709.08903). However, two rules, describing the red/green compact-structure coincidence and the important bialgebra law, had not been shown to be necessary. We present a countermodel-style argument showing that both of these rules are individually necessary relative to the connectivity meta-rule of Backens--Perdrix--Wang (arXiv:1709.08903), and hence establish that the rule set presented in arXiv:1709.08903 has no redundant rewrite rule.

2606.12381 2026-06-11 math.PR 新提交

Markov property and path regularity for the solutions to SPDEs driven by cylindrical-martingale valued measures

由柱形鞅值测度驱动的SPDE解的马尔可夫性与路径正则性

Santiago Cambronero, David Campos, C. A. Fonseca-Mora, Darío Mena

AI总结 研究由柱形正交鞅值测度驱动的随机偏微分方程的马尔可夫性,证明在时间依赖系数下解具有马尔可夫性,在时间独立系数下解具有Feller性,并在C0-半群拟压缩时解存在càdlàg版本。

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AI中文摘要

本文证明了由柱形正交鞅值测度驱动的随机偏微分方程解的马尔可夫性。我们假设系数是时间依赖的,并满足某些增长和Lipschitz条件。我们还证明,对于时间独立的系数,并且在柱形正交鞅值测度的温和假设下,我们的随机偏微分方程的解是Feller的。最后,在$C_{0}$-半群是拟压缩的情况下,我们证明我们的随机偏微分方程的解具有càdlàg版本。

英文摘要

In this paper we prove the Markov property for the solution to stochastic partial differential equations driven by a cylindrical orthogonal martingale-valued measure. We assume our coefficients are time-dependent and satisfy some growth and Lipschitz conditions. We also prove that for time-independent coefficients and under mild assumptions on the cylindrical orthogonal martingale-valued measure, the solutions to our stochastic partial differential equations are Feller. Finally, in the case that the $C_{0}$-semigroup is quasi-contraction, we show that the solution to our stochastic partial differential equation possesses a càdlàg version.

2606.12380 2026-06-11 math.CO 新提交

Forbidden Intersection Theorems for Matrix Spaces

矩阵空间中的禁止交定理

Esty Kelman, Nathan Lindzey, Ohad Sheinfeld

AI总结 研究一般线性群中矩阵族避免特定维数核交的问题,证明当t小于常数倍n时,极大家族仅由t-共治族及其对偶构成,并给出Frankl-Rödl型构造表明t>n/2时行为改变。

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AI中文摘要

一个$m \times n$矩阵族$\mathcal{F} \subseteq \mathbb{F}_q^{m \times n}$称为{$(t-1)$-无交}的,如果对所有$A,B \in \mathcal{F}$有$\dim \ker(A-B) \neq t-1$。对于矩阵集合的\emph{禁止$(t-1)$-交问题},要求在该集合中寻找极值$(t-1)$-无交族的大小和结构。我们在$\mathrm{GL}(n,q)$中解决了该问题,对所有满足$t<c\cdot n$的$(n,t)$对,其中$c$是普适常数。我们证明$t$-共治族及其对偶是仅有的极大$(t-1)$-无交族$\mathcal{F} \subset \mathrm{GL}(n,q)$。这里,$t$-共治族定义为所有在某个固定$t$维子空间上一致的矩阵族,其对偶族定义为转置在该子空间上一致的矩阵族。先前最好的结果由Ellis、Kindler和Lifshitz给出,他们在假设$n \geq e^{Ct\log t}$($C>0$为常数)下建立了该界。我们还给出了Frankl-Rödl型构造,表明该$t$的范围几乎是最好可能的:我们证明当$t>n/2$时极值行为改变,且不存在类似的简洁类比。我们的证明基于Evra、Kindler和Lifshitz最近的矩阵空间全局超收缩性结果,并广泛适用于任何足够稠密的矩阵类。

英文摘要

A family of $m \times n$ matrices $\mathcal{F} \subseteq \mathbb{F}_q^{m \times n}$ is {$(t-1)$-intersection-free} if $\dim \ker(A-B) \neq t-1$ for all $A,B \in \mathcal{F}$. A \emph{forbidden $(t-1)$-intersection problem} for a collection of matrices asks for the size and structure of extremal $(t-1)$-intersection-free families within that collection. We solve this problem in $\mathrm{GL}(n,q)$ for all pairs $(n,t)$ such that $t<c\cdot n$ where $c$ is a universal constant. We show that the $t$-umvirates and their duals, are the only maximal $(t-1)$-intersection-free families $\mathcal{F} \subset \mathrm{GL}(n,q)$. Here, a $t$-umvirate is defined as the family of all matrices that agree on a fixed $t$-dimensional subspace, and its dual as those whose transposes agree on it. The best previously known result, due to Ellis, Kindler, and Lifshitz, established this bound under the assumption $n \geq e^{Ct\log t}$ for some constant $C>0$. We also give Frankl--Rödl-type constructions showing that this range of $t$ is almost the best possible: we show that for values of $t>n/2$ the extremal behavior changes and no clean analogue is expected. Our proof builds upon recent global hypercontractivity results for matrix spaces due to Evra, Kindler, and Lifshitz, and broadly applies to any sufficiently dense class of matrices.

2606.12379 2026-06-11 math.DG 新提交

A Local Singularity Analysis for the Ricci Flow and its Applications to Ricci Flows with Bounded Scalar Curvature -- Part II

Ricci流的局部奇异性分析及其在有界标量曲率Ricci流中的应用——第二部分

Reto Buzano, Gianmichele Di Matteo

AI总结 本文延续arXiv:2006.16227的局部奇异性分析框架,研究一般Ricci流中的Type I奇点,证明标量曲率在Type I点处以Type I速率爆破,从而有界标量曲率Ricci流不会出现Type I奇点;并应用于古代Ricci流,分析曲率在负无穷时间的行为。

Comments 21 pages

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AI中文摘要

我们继续在arXiv:2006.16227中启动的Ricci流局部奇异性分析。基于该框架,我们研究一般Ricci流中的Type I奇点,不假设任何全局Type I曲率界,并证明在所有维度上,标量曲率在每个这样的点处必须以Type I速率爆破。作为推论,具有有界标量曲率的Ricci流不能发展出Type I奇点。这扩展了第一作者与Enders和Topping以及Mantegazza的早期结果,这些结果依赖于全局Type I假设。然后,我们将相同的局部视角应用于古代Ricci流,并分析曲率随时间趋于负无穷时的行为,特别表明每个古代Type I点都表现出古代Type I阶的标量曲率行为。

英文摘要

We continue our local singularity analysis for Ricci flow initiated in ArXiv:2006.16227. Building on that framework, we study Type I singular points in general Ricci flows, without assuming any global Type I curvature bound, and prove that the scalar curvature must blow up at a Type I rate at each such point in all dimensions. As a consequence, Ricci flows with bounded scalar curvature cannot develop Type I singular points. This extends earlier results of the first author with Enders and Topping and with Mantegazza that relied on a global Type I assumption. We then adapt the same local perspective to ancient Ricci flows and analyse the curvature behaviour as time goes to negative infinity, showing in particular that every ancient Type I point exhibits scalar curvature behaviour of ancient Type I order.

2606.12377 2026-06-11 math.CV 新提交

Cohomology of CR structures on compact Lie groups

紧李群上CR结构的上同调

Howard Jacobowitz, Max Reinhold Jahnke, Vinícius Novelli, Konstantin Wehler

AI总结 本文证明在除法条件下,紧李群上左不变CR结构的切Cauchy-Riemann上同调可在合适的最大环面上计算,从而得出该上同调有限维,并给出必要性条件。

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AI中文摘要

我们证明,在除法条件下,具有左不变CR结构的紧李群的切Cauchy--Riemann上同调可以在一个合适的最大环面上计算。因此,我们得出结论,切Cauchy--Riemann上同调是有限维的。我们还证明,对于一类CR结构,这个除法条件是总上同调有限维的必要条件。证明结合了紧李群上的傅里叶分析、最高权表示和李代数上同调。这不仅推广了Pittie的类似结果以及Jacobowitz和Jahnke得到的Levi-flat CR结构的推广,而且为它们提供了全新的证明。

英文摘要

We show that, under a division condition, the tangential Cauchy--Riemann cohomology of a compact Lie group with a left-invariant CR structure can be computed on a suitable maximal torus. As a consequence, we conclude that the tangential Cauchy--Riemann cohomology is finite-dimensional. We also show that, for a class of CR structures, this division condition is necessary for the total cohomology to be finite-dimensional. The proof combines Fourier analysis on compact Lie groups, highest-weight representations and Lie algebra cohomology. This not only generalizes but provides completely new proofs for the analogous result due to Pittie and for its extensions to Levi-flat CR structures, obtained by Jacobowitz and Jahnke.

2606.12376 2026-06-11 math.NT 新提交

A note on a conjecture of Ng

关于Ng猜想的一个注记

Andrew Pearce-Crump

AI总结 本文在黎曼假设和zeta函数零点均为单零点的条件下,证明了zeta函数非平凡零点上zeta函数比值第二矩的下界是猜想值的一半。

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AI中文摘要

在这篇注记中,我们给出了黎曼zeta函数非平凡零点上zeta函数比值第二矩的一个下界,该下界是猜想值的一半。我们的结果依赖于黎曼假设以及zeta函数的所有非平凡零点均为单零点的假设。

英文摘要

In this note we give a lower bound for the second moment of a ratio of zeta functions summed over the non-trivial zeros of the Riemann zeta function that is half the size of the conjectured value. Our result is conditional on the assumption of the Riemann Hypothesis and that all the non-trivial zeros of the zeta function are simple.

2606.12375 2026-06-11 cs.CE cs.NA math.NA physics.comp-ph 新提交

A coupled finite element formulation for chemo-mechano-thermodynamical contact and its application to bonding and debonding

化学-力学-热力学接触的耦合有限元公式及其在粘接与脱粘中的应用

Roger A. Sauer

AI总结 提出一种基于Sauer等人接触理论的耦合有限元公式,用于模拟化学-力学-热力学大变形接触,重点研究粘接与脱粘的演化及其与机械和热接触状态的耦合,并通过多个算例验证其通用性。

Comments 42 pages, 22 figures, 6 tables

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AI中文摘要

本文提出了一种用于耦合化学-力学-热力学大变形接触的有限元公式。该公式基于Sauer等人(2022)的接触理论,包含六个耦合但独立的场:两个接触体的变形和温度,以及界面粘接场和界面温度。后者由界面处的化学和机械能量耗散控制。这里重点研究粘接和脱粘的演化,以及它们如何与机械和热接触状态耦合。基于二次接触势,提出了几个基本模型。由此产生的接触公式变得非常通用和灵活,通过几个具有挑战性的算例进行了说明。这些算例包括压力依赖和间隙依赖的粘接、放热粘接反应、热硬化和热膨胀,以及同时发生的粘接和脱粘。它们基于使用经典和等几何形函数以及隐式时间积分的整体有限元实现。还提供了牛顿-拉夫逊求解方法所需的完全线性化。如果粘接点是材料点,则粘接变量可以在局部凝聚掉。

英文摘要

This work presents a finite element formulation for coupled chemo-mechano-thermodynamical large deformation contact. The formulation is based on the contact theory of Sauer et al. (2022) that contains six coupled (but separate) fields: the deformation and temperature of the two contacting bodies, as well as an interfacial bonding field and interfacial temperature. The latter is governed by the chemical and mechanical energy dissipation at the interface. Here the focus is placed on the evolution of bonding and debonding, and how it is coupled to the mechanical and thermal contact state. Several elementary models are proposed for this based on a quadratic contact potential. The resulting contact formulation becomes very general and versatile, which is illustrated by several challenging examples. They include pressure- and gap- depended bonding, exothermic bonding reactions, thermal hardening and thermal expansion, as well as simultaneous bonding and debonding. They are based on a monolithic finite element implementation using classical and isogeometric shape functions together with implicit time integration. Its full linearization, required for the Newton-Raphson solution method, is also provided. If bonding sites are material points, the bonding variable can be condensed-out locally.

2606.12369 2026-06-11 cs.CY 新提交

Should LLM Agents Decide in Social Simulations? Comparing Finite-State and LLM-Based Decision Policies

LLM智能体应在社会模拟中做决策吗?比较有限状态与基于LLM的决策策略

Alejandro Buitrago López, Javier Pastor-Galindo, José A. Ruipérez-Valiente

AI总结 研究评估LLM作为在线社交网络模拟中动作选择器时,是否保持可解释的参考策略,发现LLM在某些配置下可近似但不可靠地保持策略,且速度远慢于马尔可夫链采样。

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AI中文摘要

大型语言模型(LLMs)越来越多地被用作社会模拟中的决策组件。这引入了一种方法论风险:模拟可能偏离研究者定义的显式行为策略。在在线社交网络(OSN)模拟中,动作选择塑造系统动态、交互模式和模型可解释性。本文评估了LLM动作选择器在OSN模拟中是否保持可解释的参考策略。参考策略是一个实现为一阶马尔可夫模型的有限状态机,其转移概率取决于用户类型。评估使用包含1000个智能体和10000个动作决策的合成网络。测试了三种开放权重LLM:LLaMA 3.1、GPT-OSS和Mistral 24B。每个模型在三种提示策略下评估:基础、引导和概率。使用带有拉普拉斯平滑的詹森-香农散度衡量对齐度,并报告执行时间。结果表明,LLM在某些配置下可以近似参考策略,但不能可靠地保持它。对齐度因模型和提示而异,额外的引导可能引入系统性动作偏差。即使是最佳对齐的LLM配置也比直接马尔可夫链采样慢几百倍。这些发现表明,基于LLM的动作选择不能直接替代显式决策策略:它可能改变预期行为,同时增加计算成本。

英文摘要

Large language models (LLMs) are increasingly used as decision-making components in social simulations. This introduces a methodological risk: the simulation may deviate from the explicit behavioral policy defined by the researcher. In online social network (OSN) simulations, action choices shape system dynamics, interaction patterns, and model interpretability. This paper evaluates whether LLM action selectors preserve an interpretable reference policy in an OSN simulation. The reference is a finite state machine implemented as a first-order Markov model, with transition probabilities depending on the user type. The evaluation uses a synthetic network with 1,000 agents and 10,000 action decisions. Three open-weight LLMs are tested: LLaMA 3.1, GPT-OSS, and Mistral 24B. Each model is evaluated under three prompting strategies: base, guided, and probabilistic. Alignment is measured using Jensen-Shannon Divergence with Laplace smoothing, and execution time is reported. Results show that LLMs can approximate the reference policy in some configurations, but do not preserve it reliably. Alignment varies across models and prompts, and additional guidance can introduce systematic action biases. Even the best-aligned LLM configurations are several hundred times slower than direct Markov chain sampling. These findings indicate that LLM-based action selection is not a direct replacement for explicit decision policies: it can alter the intended behavior while increasing computational cost.

2606.12363 2026-06-11 quant-ph 新提交

Fermions are fundamentally more nonlocal than Bosons

费米子本质上比玻色子更非局域

Fatemeh Moradi Kalarde, Sadra Boreiri, Xiangling Xu, Lucas Tendick, Salman Beigi, Paolo Perinotti, Tommaso Guaita, Marc-Olivier Renou

AI总结 通过量子网络传输的不可区分费米子能产生比可区分粒子或不可区分玻色子更强的关联,证明费米子本质上更非局域,并引入费米子反交换和不可区分性作为操作资源。

Comments 66 pages, 9 figures; Supplementary Materials (55 pages + 7 figures) included. Comments welcome!

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AI中文摘要

贝尔定理表明,纠缠的量子粒子可以展现出经典粒子在没有额外非局域资源(如通信)的情况下无法复现的关联。在这个意义上,量子粒子本质上比经典粒子更非局域,纠缠在物理学中变得不可避免。这里我们在量子理论内部证明了类似的结果:通过量子网络传输的不可区分费米子可以产生可区分粒子或不可区分玻色子在没有额外通信的情况下无法复现的关联。在同样的意义上,费米子本质上比玻色子或可区分粒子更非局域,从而激励费米子反交换和不可区分性作为不可避免的操作资源。我们的结果进一步表明,对于某些分布式计算任务,费米子可以严格超越所有基于量子比特的协议,证明对信息处理的完整理解需要超越量子比特,走向费米子信息载体——febit。

英文摘要

Bell's theorem shows that entangled quantum particles can exhibit correlations that classical particles cannot reproduce without an additional nonlocal resource, such as communication. In this sense, quantum particles are fundamentally more nonlocal than classical ones, and entanglement becomes unavoidable in physics. Here we prove the analogous result within quantum theory itself: indistinguishable fermions transmitted through a quantum network can generate correlations that distinguishable particles or indistinguishable bosons cannot reproduce without additional communication. In the same sense, fermions are fundamentally more nonlocal than bosons or distinguishable particles, motivating fermionic anticommutation and indistinguishability as unavoidable operational resources. Our result further implies that fermions can strictly surpass all qubit-based protocols for certain distributed computing tasks, demonstrating that a complete understanding of information processing requires going beyond qubits to fermionic information carriers - febits.

2606.12361 2026-06-11 astro-ph.SR 新提交

Three-Phase Evolution of Aspect Ratio in Fast and Slow CMEs from the Sun to 1 AU

快速与慢速日冕物质抛射从太阳到1 AU的纵横比三相演化

Wageesh Mishra, Anjali Agarwal, Nandita Srivastava

AI总结 利用多视角日冕仪观测和GCS模型,结合1 AU处磁云原位测量,发现CME纵横比呈现低日冕上升、中间饱和、行星际下降的三相演化,且快速CME早期膨胀更强,慢速CME则更平缓。

Comments 16 pages, 6 figures, 3 tables; Accepted for publication in MNRAS

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AI中文摘要

日冕物质抛射(CME)在从太阳传播到1 AU的过程中经历显著的几何演化,影响其径向尺寸、膨胀和空间天气影响。我们研究了四个快速和四个慢速地球定向CME的纵横比和膨胀动力学演化。利用多视角日冕仪观测,结合渐变圆柱壳(GCS)模型和1 AU处相关磁云(MC)的校正原位测量,我们追踪了从低中冕到行星际空间的纵横比演化。我们发现纵横比并非恒定,而是呈现系统的三相演化:低中冕($\lesssim10$-$15\\,R_{\odot}$)的上升相、中间高度的饱和相,以及行星际空间的下降相。径向膨胀速度与前缘速度之比($V_{\rm exp}/V_{\rm LE}$)从日冕到1 AU显著下降,表明行星际传播过程中径向膨胀效率降低。纵横比和$V_{\rm exp}/V_{\rm LE}$的一致演化表明,从日冕中磁主导的膨胀过渡到日益受日球层环境控制的机制。我们注意到,快速CME表现出更强的早期膨胀,演变为更大、更径向延伸的结构,而慢速CME则呈现更平缓的上升和更陡峭的下降。这些结果表明,CME几何形状在传播过程中显著演化,并强调需要在模型中纳入纵横比演化,以改进对CME尺寸、到达时间和地磁效应的预测。

英文摘要

Coronal mass ejections (CMEs) undergo significant geometric evolution as they propagate from the Sun to 1 AU, influencing their radial size, expansion, and space weather impact. We investigate the evolution of CME aspect ratio and expansion dynamics for four fast and four slow Earth-directed CMEs. Using multipoint coronagraphic observations with the Graduated Cylindrical Shell (GCS) model and corrected in situ measurements of associated magnetic clouds (MCs) at 1 AU, we track the evolution of aspect ratio from the low-middle corona to interplanetary space. We find that aspect ratio does not remain constant but exhibits a systematic three-phase evolution: a rise phase in the low-middle corona ($\lesssim10$-$15\,R_{\odot}$), a saturation phase at intermediate heights, and then a decline phase in the interplanetary space. The ratio of radial expansion speed to leading-edge speed ($V_{\rm exp}/V_{\rm LE}$) decreases substantially from the corona to 1 AU, indicating a reduction in radial expansion efficiency during interplanetary propagation. The consistent evolution of aspect ratio and $V_{\rm exp}/V_{\rm LE}$ suggests a transition from magnetically dominated expansion in the corona to a regime increasingly controlled by the heliospheric environment. We note that fast CMEs show stronger early expansion and evolve into larger, more radially extended structures, whereas slow CMEs exhibit a more gradual rise and a steeper decline. These results demonstrate that CME geometry evolves significantly during propagation and highlight the need to incorporate aspect ratio evolution in models to improve predictions of CME size, arrival time, and geoeffectiveness.

2606.12359 2026-06-11 math.NT math.CO 新提交

Capparelli's partition theorem as part of an infinite hierarchy: Combinatorial and Weighted Words extensions of recent work

Capparelli 划分定理作为无限层级的一部分:近期工作的组合与加权词扩展

Yazan Alamoudi, Krishnaswami Alladi

AI总结 本文在 Capparelli 定理基础上,建立了偶数阶划分定理的双射证明,揭示了四重无限层级结构,并通过加权词方法构建了涵盖所有阶的通用框架。

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AI中文摘要

在最近的一篇论文中,作者引入了一个无限的 $q$-超几何恒等式层级,其中前三个阶 $0$、$1$ 和 $2$ 分别与 Euler、Lebesgue 和 Capparelli 的划分定理相关,并陈述了位于 Capparelli 定理之外的阶 $4$ 的划分定理。这里,我们首先陈述了在 Capparelli 之后所有偶数阶成立的某些划分定理,并给出了这些定理的双射证明。在此过程中,我们展示了存在一个从 Capparelli 定理(作为基例)出发的四重无限划分定理层级。还证明了四个生成函数中两个的等式对所有阶(奇数和偶数)都成立。最后,通过加权词方法为剩余两个函数构建了一个非常通用的框架,涵盖了所有可能的阶,并产生了具有不同伸缩和平移的多个无限层级。

英文摘要

In a recent paper, the authors introduced an infinite hierarchy of $q$-hypergeometric identities, of which the first three orders, $0$, $1$, and $2$, relate to the partition theorems of Euler, Lebesgue, and Capparelli, and stated a partition theorem at order 4 which lies beyond Capparelli's theorem. Here, we first state certain partition theorems that hold at all even orders beyond Capparelli and provide bijective proofs for these theorems. In doing so, we show that there is a fourfold infinite hierarchy of partition theorems that emanates from Capparelli's theorem, which is the base case. It is also shown that the equality of two of the four generating functions holds for all orders, odd and even. Lastly, a very general framework for the remaining two functions is constructed via the method of weighted words, encompassing all possible orders and yielding several infinite hierarchies with different dilations and translations.

2606.12357 2026-06-11 math.CT 新提交

A higher-order Eckmann-Hilton argument

高阶Eckmann-Hilton论证

Eugenia Cheng, Alexander S. Corner

AI总结 本文提出纯代数的高阶高维Eckmann-Hilton论证,证明三个适当互换的幺半结构迫使每个典范辫成为对称,并应用于n-退化半严格(n+1)-范畴。

Comments 34 pages

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AI中文摘要

我们给出了一个完全代数的、高阶高维的Eckmann-Hilton论证。首先,我们给出一个显式论证,表明如果在一个范畴上有两个具有适当互换的幺半结构,我们可以推导出其中一个幺半结构上的辫结构。然后我们证明,给定第三个幺半结构,且任意一对幺半结构之间具有适当的互换,则每个典范辫必然是对称的。作为一个激励性例子,我们证明对于$n \geq 3$,任何$n$-退化半严格$(n+1)$-范畴在其单一同态范畴上有三个适当一致的幺半结构,因此该同态范畴具有对称幺半范畴的结构。

英文摘要

We give a higher-order higher-dimensional Eckmann-Hilton argument that is entirely algebraic. First we give an explicit argument showing that if we have two monoidal structures on a category with suitable interchange, we can derive a braiding on either of the monoidal structures. Then we show that given third monoidal structure, with suitable pairwise interchange on any pair of monoidal structures, each canonical braiding is forced to be a symmetry. As a motivating example, we show that for $n \geq 3$ any $n$-degenerate semi-strict $(n + 1)$-category has three suitably coherent monoidal structures on its single hom-category, thus the hom-category has the structure of a symmetric monoidal category.

2606.12356 2026-06-11 astro-ph.HE 新提交

Stellar mass loading drives dissipation and reacceleration in AGN jets: Explaining VLBI-Gaia offsets and constraining jet power

恒星质量加载驱动AGN喷流中的耗散和再加速:解释VLBI-Gaia偏移并约束喷流功率

G. Fichet de Clairfontaine, M. Perucho, J. M. Martí, Y. Y. Kovalev

AI总结 通过RMHD模拟和辐射转移计算,发现恒星风质量加载在特定喷流功率范围内产生射电-光学质心偏移,可用于约束喷流功率和喷流-宿主耦合。

Comments Accepted for publication in A&A

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AI中文摘要

最近的甚长基线干涉测量(VLBI)和Gaia天体测量揭示了活动星系核(AGN)射电和光学质心之间存在系统性的毫角秒级偏移。这些“射电-光学偏移”并不改变标准的光深依赖的射电核心位移解释。相反,它们表明光学发射质心经常位于射电同步辐射光深$\tau = 1$面的下游,这意味着在相对论性喷流中,除了光深射电核心之外,还存在额外的耗散和粒子再加速。我们进行了AGN喷流的稳态轴对称相对论磁流体动力学(RMHD)模拟,包括来自恒星风的重子质量加载,并变化喷流动能和恒星核心半径。通过辐射传输代码生成射电和光学波段的合成同步辐射图像,并提取质心偏移以与观测比较。仅当喷流功率$L_{\rm j} \sim 10^{42.5} - 10^{44}\\,\rm{erg}\\,\rm{s}^{-1}$时,才出现秒差距尺度的射电-光学偏移。在此范围内,恒星风在固有距离约$10^2-10^3\\,\rm{pc}$处触发喷流减速,将光学质心向下游移动,产生约$0.1 - 4\\,\rm{mas}$(在$z=1$处对应几十秒差距)的偏移。偏移依赖于恒星分布、视角和光学喷流主导性,并在此功率范围外消失。我们重现了观测到的偏移发生率随红移的演化,将其与热脉动渐近巨星分支(TP-AGB)质量损失的宇宙演化联系起来。尽管恒星质量加载不太可能是唯一的耗散机制,但它在星系核中不可避免的存在使其成为能量耗散的自然基线。因此,射电-光学偏移为约束AGN喷流功率和喷流-宿主耦合提供了独立于传统射电瓣方法的手段。

英文摘要

Recent Very Long Baseline Interferometry (VLBI) and Gaia astrometry reveal systematic milliarcsecond-scale offsets between the radio and optical centroids of active galactic nuclei (AGN). These "radio-optical offsets" do not alter the standard opacity-driven interpretation of radio core shifts. Instead, they indicate that the optical emission centroid is frequently displaced downstream of the radio synchrotron optical depth $τ= 1$ surface, implying that additional dissipation and particle reacceleration occur beyond the opacity radio core within relativistic jets. We perform steady-state, axisymmetric relativistic magnetohydrodynamic (RMHD) simulations of AGN jets, including baryonic mass-load from stellar winds, varying jet kinetic power, and stellar core radius. Synthetic synchrotron emission maps in radio and optical bands are generated via a radiative transfer code, and centroid offsets are extracted for comparison with observations. Parsec-scale radio-optical offsets arise only for jet powers $L_{\rm j} \sim 10^{42.5} - 10^{44}\,\rm{erg}\,\rm{s}^{-1}$. In this regime, stellar winds trigger jet deceleration at intrinsic distances of a few $10^2-10^3\,\rm{pc}$, shifting the optical centroid downstream and producing offsets of $\sim 0.1 - 4\,\rm{mas}$ (a few tens of parsecs at $z=1$). Offsets depend on stellar distribution, viewing angle, and optical jet dominance, and vanish outside this power range. We reproduce the observed redshift evolution of offset incidence, linking it to the cosmic evolution of thermally pulsing asymptotic giant branch (TP-AGB) mass loss. Although stellar mass loading is unlikely to be the sole dissipation mechanism, its unavoidable presence in galactic nuclei makes it a natural baseline for energy dissipation. Radio-optical offsets therefore offer a constraint on AGN jet power and jet-host coupling, independent of traditional lobe-based methods.

2606.12355 2026-06-11 astro-ph.GA 新提交

Between Degeneracy and Evolution: UV-to-optical Insights into the BH$^*$ Model in Little Red Dots

介于简并与演化之间:来自紫外-光学波段对小红点中BH$^*$模型的洞察

Rosa M. Mérida, Marcin Sawicki, Chris J. Willott, Gaia Gaspar, Kartheik G. Iyer

AI总结 对66个小红点(LRDs)进行紫外-光学连续谱拟合,发现仅约6%的LRDs由BH$^*$模型最佳描述,大多数以恒星或AGN为主,表明BH$^*$与其他模型存在强简并性。

Comments 22 pages, 15 figures, 4 tables. Submitted for publication in A&A

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AI中文摘要

小红点(LRDs)是一类异质性天体,已有多种关于其物理本质和演化的理论模型。尽管这些理论已利用有限的光谱特征对个别LRDs进行了检验,但尚缺乏在宽波段范围内结合不同模型对LRD群体进行系统性贝叶斯分析。本研究利用JWST/NIRSpec PRISM光谱,对66个红移2<z<6的LRDs进行一致的紫外(UV)-光学连续谱拟合。采用修改版的Bagpipes——包括受巴尔默吸收影响的黑体(BB)辐射、经尘埃衰减的恒星和星云发射,以及活动星系核(AGN)成分——评估黑洞星(BH*)模型描述LRD群体的表现。我们采用宽先验,因此不施加任何特定的物理场景。结果显示,在具有统计稳健解的52个LRDs中,仅约6%在光学波段由BH*最佳拟合、在紫外波段由宿主星系最佳拟合。约8%的LRDs表现出BB主导的光学连续谱,但缺乏恒星成分或显示AGN紫外泄漏。大多数LRDs在光学波段由恒星和/或AGN发射主导,BB贡献较小。当我们采用不偏好强AGN连续谱的先验以强制BH*类解时,BH$^*$系统的比例增加到约40%,突显了BH*解与替代模型之间的强简并性。即使强制BH*类解,许多LRDs仍需要恒星主导的光学连续谱。这可能揭示了BH*模型的局限性,或指向一个演化序列:随着宿主增长,BB贡献减少,导致在较低红移处BB温度降低、恒星质量增大。在此情景下,更明显的“V”形对应LRD演化的较晚阶段。

英文摘要

Little Red Dots (LRDs) are a heterogeneous class of objects, with several proposed scenarios for their physical nature and evolution. While these theories have been tested on individual LRDs using limited spectral features, a systematic Bayesian analysis of the LRD population incorporating the different models across a broad wavelength range is still lacking. In this study, we conduct a consistent ultraviolet (UV)-to-optical continuum fitting analysis of 66 LRDs at 2<z<6 using JWST/NIRSpec PRISM spectroscopy. Employing a modified version of Bagpipes--including blackbody (BB) emission affected by Balmer absorption, stellar and nebular emission attenuated by dust, and an active galactic nucleus (AGN) component--we assess the performance of the black hole star (BH*) model in describing the LRD population. We adopt broad priors and therefore do not impose any specific physical scenario. Our results show that only ~6% of LRDs with statistically robust solutions (52 objects in total) are best-fit by a BH* in the optical and a host galaxy in the UV. ~8% of LRDs show BB-dominated optical continua but lack a stellar component or exhibit AGN UV leakage. Most LRDs are dominated by stellar and/or AGN emission in the optical, with minor BB contribution. When we adopt a prior that disfavors a strong AGN continuum to enforce BH*-like solutions, the percentage of BH$^*$ systems increases to ~40%, highlighting the strong degeneracy between a BH* solution and alternative scenarios. Even when BH*-like solutions are enforced, many LRDs still require a stellar-dominated optical continuum. This may reveal limitations of the BH* model or point to an evolutionary sequence in which the BB contribution decreases as the host grows, leading to lower BB temperatures and higher stellar masses at lower z. In this scenario, more pronounced ''V'' shapes would correspond to later stages in LRD evolution.

2606.12354 2026-06-11 cs.CR 新提交

ECYSAP EYE: From Cyber Situational Awareness to Mission-Centric Decision Support for Enhanced Cyberspace Operations

ECYSAP EYE:从网络态势感知到以任务为中心的决策支持,增强网络空间行动

Pantaleone Nespoli, Daniel Díaz-López, Sergio Lopez Bernal, Francisco Oliva Bermejo, Pedro González Megías, Jorge Maestre Vidal, Víctor Sobrino García, Gregorio Martínez Pérez

AI总结 提出ECYSAP EYE系统之系统架构,通过七类任务相关制品(如RCyP、CySRs等)实现从感知到决策再到执行的过渡,支持增量部署与验证,提升网络空间任务规划与执行中的态势感知与决策支持能力。

Comments 4 pages, 1 figure, 1 table, paper in proceedings of the XI National Cybersecurity Research Conference (JNIC) in Barcelona, Spain, May, 2026

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AI中文摘要

运营组织越来越需要超越孤立技术警报的网络态势感知(CySA)能力,提供可嵌入异构工具链和网络安全或网络防御流程的任务相关制品。ECYSAP EYE通过一种面向采用的系统之系统(SoS)架构满足这一需求,该架构围绕七组以任务为中心的制品:识别网络空间图(RCyP)、网络态势报告(CySRs)、假设分析报告(WIAR)、选项建议(OPRE)、操作员仪表板/人机界面(DSH)、行动执行(AE)和事后报告(AAR)。ECYSAP EYE架构构建了从感知(全频谱RCyP视图)到面向决策的推理(WIAR/CySRs/OPRE),再到操作执行和学习(DSH/AE/AAR)的过渡,具有支持增量部署和验证的明确集成面。本文从技术转移角度介绍这一创新项目,总结了更新后的架构、七组制品的功能角色,以及在任务规划与执行背景下网络态势对决策过程的预期影响。

英文摘要

Operational organizations increasingly require Cyber Situational Awareness (CySA) capabilities that go beyond isolated technical alerts, providing mission-relevant artefacts that can be embedded into heterogeneous toolchains and cyber security or cyber defense processes. ECYSAP EYE addresses this need through an adoption-oriented System-of-Systems (SoS) architecture centered on seven groups of mission-focused artefacts: the Recognized Cyberspace Picture (RCyP), Cyber Situational Reports (CySRs), the What-If Analysis Report (WIAR), Option Recommendations (OPRE), an operator Dashboard/HMI (DSH), Action Enforcement (AE), and After-Action Reports (AAR). The ECYSAP EYE architecture structures the transition from perception (full-spectrum RCyP views), to decision-oriented reasoning (WIAR/CySRs/OPRE), and to operational execution and learning (DSH/AE/AAR), with explicit integration surfaces that support incremental deployment and validation. This paper presents this innovative project from a technology transfer perspective, summarizing the updated architecture, the functional role of seven groups of artefacts, and the expected impact of cyber situations on the decision-making process in the context of a mission planning and execution.

2606.12353 2026-06-11 cond-mat.mes-hall quant-ph 新提交

Gate-tunable spin-valley transport via carrier velocity in monolayer WSe$_2$

单层WSe$_2$中通过载流子速度实现栅极可调的自旋-谷输运

Otman Bouladiane, Hocine Bahlouli, Clarence Cortes, David Laroze, Ahmed Jellal

AI总结 基于有效大质量狄拉克哈密顿量,理论研究了单层WSe$_2$中自旋和谷分辨的量子输运,发现通过调控势垒速度、标量势等参数可连续调节自旋-谷极化电流的幅值和方向。

Comments 11 pages, 9 figures

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AI中文摘要

我们理论研究了由有效大质量狄拉克哈密顿量描述的单层二硒化钨(WSe$_2$)中自旋和谷分辨的量子输运。特别关注一个有限势垒区域,其特征是同时调制的费米速度和标量势。势垒速度$v_2$通过速度比$\xi=v_2/v_1$与外部速度$v_1$相关联,这是受斯涅尔-笛卡尔定律的光学类比启发。精确的折射条件取决于完整的自旋和谷分辨色散,而简单的比例$\xi=v_2/v_1$仅在无质量对称极限下恢复。导带和价带中由$\lambda_c$和$\lambda_v$量化的本征自旋-轨道耦合与自旋和谷依赖的塞曼场$M_s$和$M_v$的相互作用导致准粒子色散发生显著变化,从而引起输运特性的显著改变。通过求解狄拉克方程并在界面处施加电流守恒匹配条件,我们计算了自旋和谷依赖的透射概率和电导。我们的结果表明,势垒速度、标量势、入射角、入射能量和势垒宽度可作为输运的有效控制参数,产生强各向异性和共振隧穿特征。此外,我们展示了自旋和谷极化电流的幅值和方向可以通过速度和势垒调制连续调节。这些发现确立了速度和势垒联合工程作为控制二维过渡金属二硫族化物中自旋-谷物理的强大理论框架。

英文摘要

We theoretically investigate spin- and valley-resolved quantum transport in monolayer tungsten diselenide (WSe$_2$) described by an effective massive Dirac Hamiltonian. Particular attention is devoted to a finite barrier region characterized by simultaneously modulated Fermi velocity and scalar potential. The barrier velocity $v_2$ is related to the external velocity $v_1$ through a velocity ratio $ξ=v_2/v_1$, motivated by an optical analogy with the Snell-Descartes law. The exact refraction condition depends on the full spin- and valley-resolved dispersion, and the simple ratio $ξ=v_2/v_1$ is recovered only in the massless, symmetric limit. The interplay of intrinsic spin-orbit coupling in the conduction and valence bands, quantified by $λ_c$ and $λ_v$, with spin- and valley-dependent Zeeman fields, $M_s$ and $M_v$, gives rise to substantial changes in the quasiparticle dispersion, leading to pronounced modifications of the transport characteristics. By solving the Dirac equation and enforcing current-conserving matching conditions at the interfaces, we compute the spin- and valley-dependent transmission probability and conductance. Our results demonstrate that the barrier velocity, scalar potential, incidence angle, incident energy, and barrier width serve as effective control parameters for transport, giving rise to strong anisotropy and resonant tunneling features. Furthermore, we show that both the magnitude and orientation of spin- and valley-polarized currents can be continuously tuned via velocity and potential modulation. These findings establish combined velocity and potential engineering as a powerful theoretical framework for controlling spin-valley physics in two-dimensional transition-metal dichalcogenides.

2606.12351 2026-06-11 math.AG math.NT 新提交

Moduli of Supersingular Abelian Varieties in Dimensions $g\leq 5$

超奇异阿贝尔簇在维数 $g\leq 5$ 上的模空间

Michael Burger

AI总结 建立极化旗型商的结构定理,证明顶层精细正规形和拟极化的可计算下降准则,完成旗型第一和最后一步分类,并计算 $g\leq 5$ 维的极化旗型商。

Comments 32 pages, comments welcome!

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AI中文摘要

我们建立了在超奇异阿贝尔簇模空间研究中出现的极化旗型商的结构定理。特别地,我们证明了这些旗的顶层的精细正规形,并推导了拟极化的显式可计算下降准则。这些结果提供了这些旗的第一步和最后一步的完整分类。作为应用,我们计算了维数 $g\leq 5$ 的极化旗型商,将截断态射的纤维描述为超奇异阿贝尔簇的分类对象。

英文摘要

We establish structure theorems for polarised flag type quotients arising in the study of the moduli space of supersingular abelian varieties. In particular, we prove a refined normal form for the top level of these flags and derive an explicit, computable descent criterion for quasi-polarisations. These results provide a complete classification of the first and last step of these flags. As an application, we compute polarised flag type quotients in dimensions $g\leq 5$, describing the fibers of the truncation morphisms as classification objects of supersingular abelian varieties.

2606.12348 2026-06-11 math.NA cs.NA 新提交

MATLAB-Based Layerwise Self-Adaptive Physics-Informed Neural Network in Applications to Multidimensional Coupled Burgers' Equations with High Reynolds Numbers

基于MATLAB的逐层自适应物理信息神经网络在高雷诺数多维耦合Burgers方程中的应用

Harish P. Bhatt, Xi Chen, Jingsai Liang

AI总结 提出一种逐层自适应加权策略的物理信息神经网络,结合双阶段优化,用于高雷诺数多维耦合Burgers方程的高精度求解,有效捕捉尖锐激波前沿。

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AI中文摘要

本文提出了一种改进的物理信息神经网络,用于模拟高雷诺数多维耦合Burgers方程的时空解剖面。随着时间演化,解中出现尖锐的激波前沿,给传统的基于网格的数值方法带来了巨大的计算挑战。特别是,有限差分和有限元等数值方法在解析陡峭解梯度时存在稳定性差和强网格依赖性的问题。为了应对这些挑战,所提出的框架采用了一种逐层自适应加权策略,在训练过程中动态调整物理残差、初始条件和边界条件的惩罚权重。此外,该框架使用双阶段优化策略以实现更稳定的收敛。为了检验所提框架的有效性和准确性,进行了一系列数值实验,将其与标准物理信息神经网络(PINN)以及使用有限记忆Broyden-Fletcher-Goldfarb-Shanno(L-BFGS)优化的PINN进行比较。数值结果表明,所提框架在相对$L_2$误差范数方面比标准PINN具有更高的精度,并且能够捕捉解中随时间演化的尖锐激波前沿的发展。

英文摘要

This paper presents an improved physics-informed neural network for simulating the spatio-temporal solution profile of the multidimensional coupled Burgers' equations with high Reynolds numbers. As time evolves, the sharp shock fronts emerge in the solution, creating significant computational challenges for the conventional mesh-based numerical methods. In particular, numerical methods such as finite differences and finite elements suffer from poor stability and strong mesh dependency when resolving the steep solution gradients. To address these challenges, the proposed framework employs a layerwise self-adaptive weighting strategy that dynamically adjusts the penalty weights for the physics residual, initial conditions, and boundary conditions throughout training. Moreover, the framework uses a dual-phase optimization strategy to achieve more stable convergence. To check the effectiveness and accuracy of the proposed framework, a set of numerical experiments is conducted to compare it with the standard Physics-Informed Neural Network (PINN) with and without Limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) optimization. Numerical results exhibit that the proposed framework achieves higher accuracy in terms of relative $L_2-$ error norm than the standard PINN and is able to capture the development of sharp shock fronts as time evolves in the solution.