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2605.16158 2026-05-18 cs.GR

Smart target point control for Gaussian Splatting methods

智能目标点控制用于高斯溅射方法

Pratik Singh Bisht, Andreas Kolb

AI总结 本文提出一种智能目标点控制方案,通过调整高斯溅射的参数以跟踪二次目标计数轨迹,确保所有方法和视图获得相等的密集化和修剪周期,实现更公平的评估。

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AI中文摘要

标准的高斯溅射方法依赖于启发式的密集化和修剪来适应性地分配基础元素,而由此产生的高斯计数强烈影响重建质量和运行时间。这使得方法间的比较容易产生偏差:改进可能源于更高的表示能力而非算法设计。常见的解决方法是在达到目标计数时停止或预算密集化/修剪,这会偏训练,因为不同方法在不同时间达到上限,导致不同视图的密集化/修剪暴露不均和点分布不均。我们提出了一种目标点控制方案,保留标准的密集化窗口和节奏,但仅调整现有的密集化和透明度剔除超参数以跟踪二次目标计数轨迹。此配额控制器在15000次迭代内达到所需计数,确保所有方法和视图获得相等的密集化和修剪周期,实现更公平、容量匹配的评估。

英文摘要

Standard Gaussian splatting methods rely on heuristic densification and pruning to adaptively allocate primitives during training, and the resulting Gaussian count strongly influences both reconstruction quality and runtime. This makes comparisons across methods fragile: improvements can stem from higher representational capacity rather than algorithmic design. A common and naive workaround for this is hard-stopping or budgeting densification/pruning once a target count is reached, which biases training because different methods hit the cap at different times, yielding non-uniform densify/prune exposure across views and uneven point distributions. We propose a target point control scheme that preserves the standard densification window and cadence, but adjusts only the existing densification and opacity-culling hyper-parameters to track a quadratic target count trajectory. This quota-governor reaches the desired count by 15k iterations without abrupt cutoffs, ensuring that all methods and views receive equal densification and pruning cycles, enabling fairer, capacity-matched evaluation.

2605.16157 2026-05-18 cs.LO

Verifiers and Generators: Epistemic Semantics for Intuitionistic Logic (Long Version)

验证者与生成器:直觉逻辑的认知语义(长版本)

Pablo Barenbaum

AI总结 本文探讨了认知可实现性,一种可判定性部分的可实现性形式。通过为每个命题A分配验证程序和生成程序,提出最小逻辑、二阶直觉逻辑和高阶直觉逻辑的认知可实现性解释,并证明每个系统在该语义下都是正确且完备的。

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AI中文摘要

本文探讨了认知可实现性,一种可判定性部分的可实现性形式。在该框架中,每个命题A被分配一个验证程序,用于检查数据X是否为A的实化,以及一个生成程序,作为X的通用实化。我们为最小逻辑、二阶直觉逻辑和高阶直觉逻辑提出了认知可实现性解释,并证明每个系统在所提出的语义下都是正确且完备的。

英文摘要

This paper explores epistemic realizability, a form of realizability in which the property that a piece of data constitutes evidence for a logical proposition is semi-decidable. In this framework, each proposition A is assigned a verifier} program that checks whether a datum X is a realizer for A, and a dual generator program that behaves as a generic realizer for X. We propose epistemic realizability interpretations for minimal logic, second-order intuitionistic logic, and higher-order intuitionistic logic, proving that each system is sound and complete under the proposed semantics.

2605.16155 2026-05-18 astro-ph.CO gr-qc

Study of dark interactions through strong gravitational lenses

通过强引力透镜研究暗物质相互作用

F. Villalobos, J. Magana, T. Verdugo

AI总结 本文通过强引力透镜数据研究暗物质与暗能量的相互作用,提出三种新的耦合模型,并发现其相互作用强度β值显著大于以往结果,表明暗能量相互作用场景。

Comments 13 pages, 8 Figures, 1 Table, to be submitted

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AI中文摘要

暗物质和暗能量之间的可能相互作用是标准ΛCDM宇宙模型的有吸引力替代方案。本文提出三种新的相互作用模型,其耦合项Q依赖于减速参数q,并与暗物质、暗能量和总能量密度成比例。通过结合强引力透镜数据,研究发现相互作用强度β值取决于耦合项Q的选择,所有模型均给出负β值,表明暗能量相互作用场景。本文得到的β值在 magnitude 上显著大于以往使用Ia型超新星、CMB和BAO数据的结果。强透镜约束表明宇宙加速转变发生在更早的红移(z_t ~ 1.8-2.1)比ΛCDM模型预测的更早,但仍与宇宙钟测量一致。因此,本文表明强引力透镜数据提供了独立且具有竞争力的宇宙学探针,能够测试相互作用的暗能量场景。透镜观测对膨胀历史的敏感性使我们能够获取关于暗物质动态的互补信息,超越标准宇宙学探针。

英文摘要

The possible interaction between the dark components of the Universe (dark matter and dark energy) stands as an attractive alternative to the standard $Λ$CDM cosmological model. In this work, we present a novel analysis of three sign-changeable interaction models whose coupling term $Q$ depends explicitly on the deceleration parameter $q$ and is proportional to different energy densities: dark matter, dark energy, and total energy density. To constrain these models, we combine strong gravitational lensing data on two complementary scales: a sample of early-type galaxies acting as lenses and the galaxy cluster Abell 1689. Our results show that the interaction strength $β$ depends on the choice of the coupling term $Q$, with all models yielding negative values of $β$, indicative of a dark interaction scenario. The $β$ values obtained in this work are significantly larger in magnitude than those previously reported using Type Ia supernovae, CMB, and BAO. The strong-lensing constraints indicate a transition to cosmic acceleration at earlier redshifts ($z_t \sim 1.8-2.1$) than that predicted by the $Λ$CDM model, while remaining consistent with cosmic chronometer measurements within the reconstructed confidence regions. Therefore, our study shows that strong gravitational lensing data provide an independent and competitive cosmological probe capable of testing interacting dark energy scenarios. The sensitivity of lensing observables to the expansion history enables access to complementary information about dark-sector dynamics beyond standard cosmological probes.

2605.16152 2026-05-18 math.CO

Whitney's 2-isomorphism theorem for graphings

图形的惠特尼2同构定理

Márton Borbényi, Grigory Terlov, László Márton Tóth

AI总结 本文证明了图形在可测意义下的惠特尼定理,引入了弱同构的概念,并展示了无限端点图形的弱同构性与同构性的关系,发展了最近由Lovász发起的极限理论。

Comments 32 pages, 14 figures

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AI中文摘要

我们证明了可测意义下的惠特尼经典定理关于有限图的弱同构性。在局部有限图形的设定中,我们引入了弱同构的概念,即一种保持边测度和循环及超有限子图的Borel双射,模去零测集。我们首先证明了一个刚性定理,证明对于弱3连通无限端点图形,每个弱同构都是由图形的同构诱导的。到目前为止,这给出了可测组合学中第一个一般充分条件,用于证明两个给定图形之间的同构存在性。接着,我们给出了惠特尼定理的完整可测版本,证明了每个图形之间的弱同构都可以通过可数多个可测惠特尼操作实现,我们在该设定中引入了这些操作。证明需要新的可测组合工具,包括对无限端点子森林的仔细分析。这项工作进一步发展了最近由Lovász发起的 matroid 极限理论。

英文摘要

We prove measurable analogues of Whitney's classical theorems on weak isomorphisms of finite graphs. In the setting of locally finite graphings, we introduce a notion of weak isomorphism as an edge-measure-preserving Borel bijection that preserves cycles and hyperfinite subgraphs, modulo null sets. We first show a rigidity theorem, proving that for weakly 3-connected infinitely-ended graphings, every weak isomorphism is induced by an isomorphism of graphings. To our knowledge, this gives the first general sufficient condition in measurable combinatorics for the existence of an isomorphism between two given graphings. Next, we give a full measurable version of Whitney's theorem, showing that every weak isomorphism between graphings can be implemented by countably many measurable Whitney operations, which we introduce in this setting. The proofs require new measurable-combinatorial tools, including a careful analysis of infinitely-ended subforests. This work further develops the limit theory of matroids recently initiated by Lovász.

2605.16151 2026-05-18 quant-ph

Generalized measurement incompatibility

广义测量不兼容性

Edwin Peter Lobo, Maria Balanzó-Juandó, Stefano Pironio

AI总结 本文研究了广义部分联合可测性,提出两种数学表征,并证明其可通过半正定规划决定。研究发现,在不可信测量设备中,只有当测量集部分联合可测时,攻击者才能完美猜测结果,并推导出检测效率阈值。

Comments 12+7 pages, 4 figures

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AI中文摘要

量子测量可以不兼容,即无法同时测量。Masini等人提出了较弱的联合可测性概念,称为部分联合可测性。本文进一步将其推广到仅需部分测量结果由经典变量确定的场景。我们提供了两种数学表征,并证明可通过单个半正定规划决定。证明在不可信测量设备中,攻击者若受限于经典侧信息,只有当测量集部分联合可测时才能完美猜测结果。推导出检测效率阈值,表明通用测量在该阈值以下成为部分联合可测。这些界限直接限制了设备无关和半设备无关量子密码协议对检测效率的鲁棒性。特别地,研究强调了在安全分析中对后选择的谨慎处理的重要性。

英文摘要

Quantum measurements can be incompatible, i.e., they can fail to be jointly measurable. Recently, a weaker notion of joint-measurability, called partial joint-measurability, was proposed by Masini et al. in [Quantum 8, 1574 (2024)]. In this work, we further generalize this notion to the setting where only a subset of the outcomes of each measurement is required to be jointly determined by classical variables. We provide two mathematical formulations of partial joint-measurability and show that, like full joint-measurability, it can be decided by solving a single semidefinite program. We prove that in the case of an untrusted measurement device, an adversary Eve, limited to classical side information, can perfectly guess the outcomes of the measurement device if and only if the set of measurements is partially jointly measurable. We derive analytical thresholds on the detection efficiency below which generic measurements become partially jointly measurable. Such bounds directly yield limits on the robustness of device-independent and semi-device-independent quantum cryptographic protocols against detection inefficiency. In particular, our results highlight the importance of a careful treatment of postselection in security analyses.

2605.16149 2026-05-18 physics.plasm-ph cond-mat.stat-mech

Beyond Maxwell-Boltzmann: Transport in Quasiequilibrium Plasmas

超越麦克斯韦-玻尔兹曼:准平衡等离子体中的输运

Kamel Ourabah

AI总结 研究准平衡等离子体中输运现象,通过超统计学方法推导输运系数,发现非麦克斯韦分布显著增强输运系数,解释为高能粒子的增加。

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AI中文摘要

空间等离子体通常表现出非麦克斯韦分布,具有超热粒子群,这通常通过现场观测揭示。这种偏离标准麦克斯韦分布可以理解为准平衡状态的特征,其中介质的分布可以表示为连续超位置麦克斯韦分布的叠加,即通过超统计学。本文构建了连接通量与其相关驱动力的宏观关系,在此类等离子体中,超统计效应通过输运系数进入。通过将结果超统计分布与日球层中观测到的电子分布进行比较,我们转向准平衡等离子体的动能响应,并推导出相应的输运系数,包括电导率、热导率、迁移率和扩散系数。我们进一步将分析扩展到粘性等离子体,并计算剪切粘度和体积粘度系数。总体而言,准平衡效应被发现系统性地增强了输运系数相对于麦克斯韦值。我们为超统计学的三种主要普遍类别的输运系数量化了这种增强,这些类别在实验和观测情况下最常遇到,并将其解释为非麦克斯韦尾部中高能粒子数量增加的结果。

英文摘要

Space plasmas are generally characterized by non-Maxwellian distributions with suprathermal populations, as routinely revealed by in situ observations. Such departures from standard Maxwellian distributions can be understood as signatures of quasiequilibrium states, in which the distribution of the medium can be expressed as a continuous superposition of Maxwellian distributions, namely through superstatistics. Here, we construct macroscopic relations linking fluxes to their associated driving forces in such plasmas, where superstatistical effects enter the picture through the transport coefficients. After comparing the resulting superstatistical distributions with observed electron distributions in the solar wind, we turn to the kinetic response of quasiequilibrium plasmas and derive the corresponding transport coefficients, including the electric and thermal conductivities, the mobility, and the diffusion coefficient. We further extend the analysis to viscous plasmas and compute the shear and bulk viscosity coefficients. Overall, quasiequilibrium effects are found to systematically enhance the transport coefficients relative to their Maxwellian values. We quantify this enhancement for the three main universality classes of superstatistics, which are the most commonly encountered in experimental and observational situations, and interpret it as a consequence of the increased population of energetic particles in the non-Maxwellian tails.

2605.16146 2026-05-18 q-bio.NC

The Complex Brain Hypothesis: Resolving the Entropy-Content Conundrum in Minimal Phenomenal Experience

复杂大脑假说:解决最小现象体验中的熵-内容困境

Jonas Mago, Edmundo Lopez-Sola, Jakub Vohryzek, Michael Lifshitz, Robin Carhart-Harris, Karl Friston, Shamil Chandaria

AI总结 本文提出复杂大脑假说,认为现象丰富性应由大脑复杂性而非熵来衡量,通过分析不同意识状态的神经机制,澄清了最小现象体验与高内容体验之间的差异。

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AI中文摘要

最小现象体验(MPEs)是意识状态,其中清醒保持但现象内容低或缺失。熵脑假说(EBH)将自发脑活动的熵视为'现象丰富性'的标志,例如高内容迷幻体验(HCPEs)。然而,最近的人脑成像研究显示,由冥想或5-MeO-DMT诱导的MPEs表现出增加的神经生理熵。这给EBH带来困境:脑熵在现象丰富性增加或减少时都升高。本文提出复杂大脑假说(CBH),认为现象丰富性应由复杂性而非熵来衡量。我们论证大脑复杂性受推理粒度调节:某些HCPEs体现细粒度模式,放松约束放大波动产生丰富内容;某些MPEs体现粗粒度模式,简单模型溶解多样性产生'无内容'意识。两种模式均可与高脑熵相关,但现象学和扰动特征不同。通过解决熵-内容困境,CBH改进EBH并强调MPEs作为意识计算理论的重要测试案例。

英文摘要

Minimal Phenomenal Experiences (MPEs) are states of consciousness in which wakefulness is preserved but phenomenal content is low or absent. The Entropic Brain Hypothesis (EBH) is a model of conscious processes that regards the entropy of spontaneous brain activity as a marker of 'phenomenal richness', exemplified by high-content psychedelic experiences (HCPEs). Yet recent human neuroimaging studies of MPEs induced by meditation -- and possibly 5-MeO-DMT -- suggest that these states, defined by their phenomenological simplicity, also show signs of increased neurophysiological entropy. This presents a conundrum for the EBH: brain entropy is elevated with increased and decreased richness of the phenomenal experience. Here, we put forward the Complex Brain Hypothesis (CBH), which proposes that the richness of experience differentiating MPEs from HCPEs is better indexed by complexity than by entropy. We argue that brain complexity is modulated by the grain of inference through which the brain resolves uncertainty: some HCPEs exemplify a fine-grained regime, in which loosened constraints amplify fluctuations into proliferating content, whereas some MPEs exemplify a coarse-grained regime, in which a simpler model dissolves variety into an experience of 'contentless' awareness. Both regimes can be associated with elevated brain entropy, but they diverge in phenomenology and perturbational signatures. By resolving the entropy-content conundrum, the CBH refines the EBH and highlights MPEs as an important test case for computational theories of consciousness.

2605.16144 2026-05-18 eess.SP cs.MA cs.NI

MAxLM: Multi-Agent Language Model-Based Scheduling and Resource Allocation in MU-MIMO-OFDMA-Enabled Wireless Networks

MAxLM:基于多智能体语言模型的MU-MIMO-OFDMA无线网络调度与资源分配

Adnan Quadri, Hongxiang Li

AI总结 本文提出MAxLM框架,利用预训练语言模型优化无线网络的上行调度接入,通过WiSER平台实现自主调度与资源分配,实验表明其在不同STA数量和天线设置下均优于基准方法。

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AI中文摘要

无线网络通过MIMO和OFDMA技术支持多用户通信,本文研究了联合MU-MIMO-OFDMA传输模式下用户调度与资源分配(SRA)的优化方法。我们提出一种多智能体(MA)框架,利用预训练的小型/中型语言模型(xLM)进行SRA优化,并引入AI辅助的无线系统工程与研究(WiSER)平台以实现自主SRA。通过在WLAN接入点上评估不同STA数量和天线设置的网络场景,数值结果证实所提技术在上行调度接入(UL-SA)吞吐量上优于基准方法。

英文摘要

Wireless networks support multi-user (MU) communication with multiple-input multiple-output (MIMO) and orthogonal frequency-division multiple access (OFDMA) technologies. In the joint MU-MIMO-OFDMA-enabled transmission mode, network throughput can be significantly increased by effectively utilizing the multi-channel resources to schedule numerous wireless users/stations (STAs) simultaneously. In this paper, we study ways to optimize the user scheduling and resource allocation (SRA) for the UL scheduled access (UL-SA) of a joint MU-MIMO-OFDMA-enabled wireless local area network (WLAN). In particular, we propose a multi-agent (MA) framework that utilizes an openly available pretrained small/medium-sized Language Model (xLM) to perform SRA for the UL-SA. To facilitate autonomous SRA using our proposed technique, we introduce the AI-assisted Wireless Systems Engineering and Research (WiSER) platform. We evaluate the performance of MAxLM-optimized SRA for network scenarios with a varying number of STAs and antenna settings on the WLAN Access Point. Numerical results confirm that our proposed technique achieves higher UL-SA throughput than the benchmark techniques.

2605.16141 2026-05-18 eess.SP

SiFo: Wireless Foundation Model for Low-Overhead Site-Specific CSI Feedback

SiFo:面向低开销的特定站点信道状态信息反馈无线基础模型

Cheng-Jie Zhao, Zhaolin Wang, Zongyao Zhao, Yuanwei Liu

AI总结 SiFo提出一种基于无线基础模型的框架,通过预训练和轻量级校准实现高效特定站点CSI反馈,提升频谱效率。

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AI中文摘要

SiFo,一种基于无线基础模型的框架,被提出用于低开销的特定站点信道状态信息(CSI)反馈。在3GPP NR中,类型II反馈提供了一种基于代码表的CSI表示,但需要大量的参考信号开销、用户端搜索和反馈。基于学习的特定站点反馈可以通过利用部署相关的传播结构来减少这些在线成本,同时保持高质量的子空间表示。然而,现有特定站点设计通常为每个新站点训练专用神经网络,这在部署数量大时限制了可扩展性。SiFo通过在源站点上预训练CSI反馈模型,并通过轻量级校准适应目标站点来解决可扩展性问题。一小组目标站点用户报告低维参考信号接收功率(RSRP)指纹,并将基于完整CSI的子空间标签存储为校准记忆。在在线操作期间,被服务用户通过相同的SSB探测和RSRP报告过程与校准用户匹配,因此附近的校准样本提供特定站点的子空间指导,而无需更新模型参数。SiFo因此在转移通用传播知识的同时保留了本地适应性。在十个城市场景中的数值结果表明,SiFo(i)在相同的目标站点标记预算下,比单独训练的特定站点学习基线具有更高的CSI捕获效率;(ii)仅使用在线SSB探测期间收集的RSRP测量值即可接近高开销3GPP NR类型II反馈参考;(iii)在有限的目标站点数据下,将高CSI捕获效率和低开销转化为有效的频谱效率提升。

英文摘要

SiFo, a wireless foundation model-based framework, is proposed for low-overhead site-specific channel state information (CSI) feedback. In 3GPP NR, Type-II feedback provides an expressive codebook-based CSI representation, but it requires substantial reference-signal overhead, UE-side search, and feedback. Learning-based site-specific feedback can reduce these online costs while retaining high-quality subspace representation by exploiting deployment-dependent propagation structure. However, existing site-specific designs typically train a dedicated neural network for each new site, which limits scalability when the number of deployments is large. SiFo addresses this scalability issue by pretraining a CSI feedback model across source sites and adapting it to a target site through lightweight calibration. A small set of target-site users reports low-dimensional reference signal received power (RSRP) fingerprints, and their full-CSI-based subspace labels are stored as calibration memory. During online operation, a served user is matched to calibrated users through the same SSB probing and RSRP reporting procedure, so nearby calibration samples provide site-specific subspace guidance without updating model parameters. SiFo therefore transfers common propagation knowledge while retaining local adaptation. Numerical results across ten city scenarios demonstrate that SiFo (i) achieves higher CSI-capture efficiency than separately trained site-specific learning baselines under the same target-site labeled budget, (ii) approaches the high-overhead 3GPP NR Type-II feedback reference using only RSRP measurements collected during online SSB probing, and (iii) converts the high CSI-capture efficiency and low overhead into effective spectral efficiency improvement under limited target-site data.

2605.16140 2026-05-18 cs.IT cs.SY eess.SY math.IT math.ST stat.TH

Covert Bayesian Quickest Change Detection

隐蔽的贝叶斯最快变化检测

Yun-Feng Lo, Matthieu R. Bloch

AI总结 研究在贝叶斯和无限时间框架下隐蔽最快变化检测问题,提出隐蔽预算指标,分析在误报概率和隐蔽预算约束下检测延迟的第二阶界限,并提出可行方案。

Comments 36 pages, 2 figures. Submitted to IEEE ITW 2026

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AI中文摘要

我们研究在贝叶斯和无限时间框架下隐蔽最快变化检测问题。一个合法实体通过主动探测离散无记忆信道来尽可能快地检测状态变化,同时确保其探测行为对监控主动传感的对手保持隐蔽。我们引入预期隐蔽预算(ECB)作为可分析的隐蔽度量指标,该指标界定了主动和被动传感诱导的观测序列之间的相对熵上限。在误报概率(PFA)和ECB约束下,我们建立了平均检测延迟的第二阶渐进对偶界,当PFA约束趋近于零时,对于任何正的ECB约束,明确量化了最大平方根阶隐蔽传感增益。此外,我们提出了一种利用恒定传感概率的Shiryaev型策略的可行方案,并展示了该方案与第二阶渐进对偶界的一致性。我们通过数值示例来说明结果。

英文摘要

We investigate the problem of covert quickest change detection in a Bayesian and infinite-horizon setting. A legitimate entity seeks to detect a change in the state of a discrete memoryless channel as quickly as possible by actively probing it. Simultaneously, the entity must ensure its probing remains covert from an adversary monitoring the channel for active sensing. We introduce the expected covertness budget (ECB) as an analytically tractable covertness metric that bounds from above the relative entropy between the observation sequences induced by active and passive sensing. Under constraints on both the probability of false alarm (PFA) and the ECB, we establish a second-order asymptotic converse bound on the average detection delay as the PFA constraint approaches zero, for any positive ECB constraint, explicitly quantifying the maximum square-root-order covert sensing gain possible. Furthermore, we propose an achievability scheme utilizing a constant-sensing-probability Shiryaev-type policy and show that it matches the second-order asymptotic converse. We illustrate our result with a numerical example.

2605.16139 2026-05-18 math.FA

Block-equivalent finite Gabor frames

块等价有限Gabor框架

Oleg Asipchuk, Laura De Carli, Luis Rodriguez

AI总结 本文研究了通过显式且计算高效的酉变换将有限向量系统框架算子矩阵酉等价于块对角矩阵的系统,证明当调制集或位移集为Z_N子群时,Gabor系统为块等价,并探讨了框架算子矩阵对角化的条件。

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AI中文摘要

我们研究了通过显式且计算高效的酉变换将有限向量系统的框架算子矩阵酉等价于块对角矩阵的系统,称为块等价系统。我们证明当调制集L或位移集K为Z_N子群时,Gabor系统G=G(g,L×K)⊂C^N是块等价的。我们还刻画了框架算子矩阵成为对角矩阵的情况。最后,我们证明几何条件迫使某些框架算子矩阵的对角线消失,从而产生额外的稀疏性和块结构。

英文摘要

We study finite systems of vectors whose frame operator matrices are unitarily equivalent, via explicit and computationally efficient unitary transformations, to block-diagonal matrices. We call such systems block-equivalent. We show that a Gabor system $\mathcal{G}=\mathcal{G}(g,L\times K)\subset \mathbb C^N$ is block-equivalent when either the modulation set $L$ or the translation set $K$ is a subgroup of $\mathbb Z_N$. We also characterize situations in which the frame operator matrix becomes diagonal. Finally, we show that geometric conditions on subsets of $\mathbb Z_N$ force certain diagonals of the frame operator matrix of $\mathcal{G}$ to vanish, yielding additional sparsity and block structures.

2605.16136 2026-05-18 nlin.SI

Lie symmetry classification of a coupled nonlinear cross-diffusion system in radial geometry

径向几何中耦合非线性交叉扩散系统的Lie对称分类

Manjit Singh, Radhika

AI总结 本文通过Lie对称分析研究了具有变化横截面几何的耦合非线性交叉扩散系统,揭示了其在径向结构下的对称性质及非线性耦合对对称性的限制。

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AI中文摘要

本文对具有变化横截面几何的耦合非线性交叉扩散系统进行了Lie对称分析。该系统描述了两个相互作用的量,其材料属性,即容量函数和扩散系数,非线性地依赖于依赖变量。经典Lie不变性准则产生了一组十六个确定方程用于无穷小对称生成元。通过建立允许生成元的通用几何结构,并根据状态空间中的不变性性质对构成函数进行分类,解这些确定方程。研究表明,系统始终允许时间平移和抛物线缩放作为核对称性,仅在笛卡尔情况下允许额外的空间平移。通过关于构成函数的精确结构假设,获得了如平移、缩放和依赖变量平面中的旋转等进一步对称性。分析显示,强非线性耦合在一般情况下禁止新的点对称性出现,而更大的对称代数仅在退化或可线性化的特殊情况下才能实现。本文获得的对称性与 governing 方程的抛物线和径向结构在几何上一致。

英文摘要

In this work, Lie symmetry analysis is performed on a coupled nonlinear cross-diffusion system with varying cross-section geometry. The system describes two interacting quantities whose material properties, namely the capacity functions and the diffusion coefficients, depend nonlinearly on the dependent variables. The classical Lie invariance criterion produces a set of sixteen determining equations for infinitesimal symmetry generators. The determining equations are solved by first establishing the universal geometric structure of the admitted generators and then classifying the constitutive functions according to their invariance properties in the state space. It is shown that the system always admits time translation and parabolic scaling as kernel symmetries, with an additional spatial translation admitted only in the Cartesian case. Further symmetries, such as translations, scalings, and rotations in the dependent-variable plane, are obtained by making precise structural assumptions about the constitutive functions. The analysis shows that the strong nonlinear coupling in the governing equations prohibits any new point symmetries from arising in the general case, and that larger symmetry algebras are only attainable in degenerate or linearizable special cases. The symmetries obtained in this work are geometrically consistent with parabolic and radial structure of governing equations.

2605.16135 2026-05-18 quant-ph physics.optics

Sub-picosecond inter-core skew characterization in multicore fibers via Hong--Ou--Mandel interference

多芯光纤中亚皮秒级芯间偏移特性 characterization via Hong--Ou--Mandel 干涉

L. Lira Tacca, L. Marques Fagundes, M. Morales Lillo, M. Navarro, I. Machuca, S. Gómez, G. H. dos Santos, J. Cariñe, G. Saavedra, E. S. Gómez, G. Lima, S. P. Walborn

AI总结 本文通过光纤集成的4×4多端口光束分离器利用双光子Hong--Ou--Mandel干涉测量多芯光纤中芯间偏移特性,实现了±0.11 ps的高精度测量,展示了随机游走尺度的验证。

Comments 15 pages, 4 figures. Comments welcome!

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AI中文摘要

芯间偏移(ICS),多芯光纤(MCF)中各芯群延迟差的关键参数,对于经典空间分割复用通信和量子光网络均至关重要。我们通过双光子Hong--Ou--Mandel(HOM)干涉在光纤集成的4×4多端口光束分离器中,对商用四芯光纤中的ICS进行了高精度测量。通过提取所有十二个芯对组合中的HOM干涉凹陷和峰值中心位置,我们获得了具有±0.11 ps精度的单个ICS值,该精度受限于延迟阶段定位不确定性。根均方ICS随着σ_τ(L) = κ√L + c增长,其中κ=48.7±2.5 ps/√km,c=9.76±1.2 ps,在7.7 m至1300 m的光纤长度范围内。通过HOM对一阶路径波动的不敏感性,实现了从实验室到现场部署尺度的随机游走尺度的首次直接验证,这使得经典干涉测量方法在长安装光纤中不切实际。所展示的±0.11 ps精度代表了与相关光学时域反射计(C-OTDR)相比的约180倍改进。Fisher信息分析建立了皮秒范围内的Cramér-Rao精度极限,表明通过更好的延迟控制可以进一步改进。这些结果建立了一个实际平台,用于在基于多芯光纤的网络中表征时间均匀性,适用于量子和经典空间分割复用应用。

英文摘要

Inter-core skew (ICS), the differential group delay between cores of a multicore fiber (MCF), is a critical parameter for both classical space-division multiplexed communications and quantum photonic networks. We present a high-precision measurement of ICS in a commercially available four-core fiber using two-photon Hong--Ou--Mandel (HOM) interference in a fiber-integrated $4\times4$ multiport beam splitter. By extracting the center position of HOM interference dips and peaks across all twelve core-pair combinations, we obtain individual ICS values with a demonstrated precision of $\pm0.11\,$ps, limited by the delay-stage positioning uncertainty. The root-mean-square ICS grows as $σ_τ(L) = κ\sqrt{L}+c$ with $κ= 48.7 \pm 2.5\,\mathrm{ps}/\!\sqrt{\mathrm{km}}$ and $c = 9.76 \pm 1.2\,$ps, over fiber lengths from $7.7\,$m to $1300\,$m. This first direct validation of the stochastic random-walk scaling across a length range spanning laboratory to field-deployed scales was made possible by HOM's immunity to first-order path fluctuations, which renders classical interferometric methods impractical for long installed fibers. The demonstrated $\pm0.11\,$ps precision represents a $\sim\!180$-fold improvement over correlation optical time-domain reflectometry (C-OTDR), the standard method for long-fiber ICS characterization. Fisher information analysis establishes a fundamental Cramér--Rao precision limit in the femtosecond range, indicating further improvement is achievable with better delay control. These results establish a practical platform for characterising timing uniformity in MCF-based networks for both quantum and classical space-division multiplexed applications.

2605.16133 2026-05-18 cs.SE

The Dangers of Non-Self-Fixed Architecture Technical Debt and Its Impact on Time-to-Fix

非自修复架构技术债的危险及其对修复时间的影响

Edi Sutoyo, Paris Avgeriou, Andrea Capiluppi

AI总结 本文研究了非自修复架构技术债的修复责任及影响,通过分析开源项目发现自修复与非自修复技术债在修复时间和协作因素上有显著差异,为维护者提供识别高风险技术债和减少交接成本的指导。

Comments This manuscript is currently under review

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AI中文摘要

技术债(TD)指的是开发人员为短期交付而优先于质量改进工作所产生长期成本。架构技术债(ATD)发生在架构决策(如技术选择、模式或分解)优先考虑短期进展而非未来可维护性和可扩展性时。由于ATD影响系统核心结构并传播通过架构依赖,其修复通常比局部代码级债务更昂贵和破坏性。尽管ATD已被广泛研究,但偿还责任这一重要但未被深入探讨的方面仍缺乏实证证据。本文通过分析大型Apache开源项目中的自修复ATD和非自修复ATD,追踪Jira工件和版本控制历史以重建ATD生命周期,识别引入和偿还点并归因开发者角色。研究探讨了自修复ATD的普遍性、自修复与非自修复项目之间的修复时间差异,以及与代码变更和协作指标相关的偿还速度因素。通过描述性统计、非参数检验和生存分析,研究发现自修复和非自修复ATD在偿还动态和变更共享方式上存在显著差异。特别是非自修复ATD在变更分散到多个开发者时更可能长期未解决。这些结果为维护者提供了识别高风险ATD项目和通过增加引入者参与及在偿还时记录设计理由以减少交接成本的可行指导。

英文摘要

Technical Debt (TD) refers to the long-term costs incurred when developers prioritize short-term delivery over quality-improving work. Architectural Technical Debt (ATD) arises when architectural decisions (e.g., technology choices, patterns, or decomposition) prioritize near-term progress over future maintainability and evolvability. Because ATD affects a system's core structure and propagates through architectural dependencies, it is often more expensive and disruptive to remediate than localized code-level debt. Although ATD has been widely studied, an important but underexplored aspect of repayment is who performs it. Prior work provides limited empirical evidence on repayment responsibility in ATD and its relationship to time-to-fix. We empirically study self-fixed ATD, where the introducer also repays the debt, and contrast it with non-self-fixed ATD in large Apache open-source projects. We reconstruct ATD lifecycles by tracing Jira artifacts to version-control history to identify introduction and repayment points and attribute developer roles. We address three research questions on the prevalence of self-fixed ATD, time-to-fix differences between self-fixed and non--self-fixed items, and how factors related to code change and collaboration metrics relate to repayment speed. Using descriptive statistics, non-parametric tests, and survival analysis, we show that self-fixed and non--self-fixed ATD exhibit distinct repayment dynamics and differences in how changes are shared on ATD-affected files. In particular, non--self-fixed ATD is more likely to remain unresolved longer when changes are spread across many developers. These results provide actionable guidance for maintainers to identify high-risk ATD items and to reduce handoff costs by increasing introducer involvement when possible and documenting the design rationale during repayment.

2605.16132 2026-05-18 astro-ph.HE

Nucleosynthesis in the fast ejecta of a neutron star merger

中子星合并的快速抛射物中的核合成

Lukas Schnabel, Stephan Rosswog, Friedrich-Karl Thielemann, Moritz Reichert

AI总结 研究中子星合并快速抛射物中核合成的三个通道,发现自由中子在r过程冻结后仍能存活,其β衰变主导加热率,产生显著的蓝前导光变,可能被ULTRASAT观测到。

Comments Submitted to MNRAS, 15 pages, 14 figures

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AI中文摘要

中子星合并被认为是快速中子捕获元素的主要产生地。尽管大部分物质以高速但非相对论性速度(约0.2c)逃逸,一小部分动态抛射物以 mildly 相对论性速度(>0.6c)逃逸。此前有建议指出,在这些抛射物中中子可能避免被捕获,其衰变可能驱动主千赫诺娃事件之前的蓝色前导光变。本文通过核网络计算研究了这些快速抛射物中的核合成,沿参数化和数值相对论轨迹进行。研究发现核合成可分为三个通道,其中一通道中大量自由中子在r过程冻结后仍存活。我们提供了一个(半)解析模型用于存活自由中子,与网络计算结果非常吻合。如果自由中子的质量分数超过约0.05,其β衰变将主导核加热率在约100至10^4秒之间。这种主导导致显著的千赫诺娃前导光变,对于合理的抛射物参数,应能被ULTRASAT观测到约200 Mpc范围。由于在低电子分数下自由中子即使在中等速度下也能存活,具有大潮汐抛射物的合并,如不对称中子星合并或有利的中子星黑洞合并,可能产生特别明亮的蓝前导光变。

英文摘要

Neutron star mergers are today considered a major production site for rapid neutron capture elements. While the bulk of the matter escapes at fast, but non-relativistic velocities (${\sim} 0.2\,c$), a small amount of the dynamically ejected mass reaches mildly relativistic velocities (${\gtrsim}0.6\,c$). It has been suggested earlier, that in such ejecta parts neutrons may avoid being captured and that their decay could power an early blue precursor to the main kilonova event. Here we study in detail the nucleosynthesis in such fast ejecta with nuclear network calculations along both parametrized and numerical relativity trajectories. We find that the nucleosynthesis can be divided into three channels, in one of which a substantial amount of free neutrons survives when the main r-process has frozen out. We provide a (semi-)analytical model for surviving free neutrons which agrees very well with the network calculations. If the mass fraction of the free neutrons exceeds ${\sim} 0.05$, their $β^-$-decay dominates the nuclear heating rate between ${\sim} 100$ and ${\sim} 10^4$ seconds. This dominance leads to a pronounced kilonova precursor that should for plausible ejecta parameters be visible for ULTRASAT out to ${\sim}200\,\rm Mpc$. Since at low electron fractions free neutrons can survive even for moderate velocities, mergers with large tidal ejecta, such as asymmetric neutron star mergers or favorable neutron star black hole mergers, may produce particularly bright blue precursors to their subsequent kilonovae.

2605.16131 2026-05-18 quant-ph cond-mat.quant-gas

Extensive mixed-state entanglement in kinetically constrained superradiance

大量混合态纠缠在动能受限的超辐射中

Lucas Winter, Jan Kumlin, Thomas Pohl, Andreas Nunnenkamp

AI总结 研究通过引入局部动能约束,在保持Dicke超辐射核心特征的同时,产生大量混合态纠缠。分析得出发射率下限,推导出峰值强度与时间关系,并展示其在中性原子阵列中的实验实现可能性。

Comments 5 pages, 4 figures, 24 pages supplemental information

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AI中文摘要

由量子发射体集体产生的超辐射产生集体辐射爆发,但无混合态纠缠。我们展示添加本地动能约束可生成大量混合态纠缠,同时保持超辐射核心特征。对于任意局部布尔约束,推导出发射率下限,推导出峰值强度∝N²和峰值时间∝(log N)/N(N为自旋数)。该效应使超辐射加速制备纠缠暗态。Hilbert空间碎片化导致指数分支衰减树生成暗态层级。这些不连通 manifold 包含指数多的长程纠缠singlet暗态。探索的动能约束和超辐射动力学可在中性原子阵列与光学腔耦合中实现,并提出简单可检测的混合态纠缠见证方法。此外,纠缠生成对原子衰减和集体退相位具有鲁棒性,应在最近报告的实验条件下可观测。我们的结果提供了一般框架和实验可行方法,用于通过超辐射增强的耗散工程制备纠缠暗态。

英文摘要

Dicke superradiance by an ensemble of quantum emitters produces a collective burst of radiation, but no entanglement in the mixed state of the emitters. We show that adding a local kinetic constraint between the emitters generates extensive mixed-state entanglement, while otherwise preserving all key features of Dicke superradiance. Specifically, for any local Boolean constraint, we analytically derive a lower bound for the emission rate which implies a peak intensity $\propto N^2$ and a peak time $\propto (\log N)/N$ with number of spins $N$. This effect enables the superradiantly accelerated preparation of entangled dark states. Hereby, Hilbert-space fragmentation of the Dicke ladder leads to an exponentially branching decay tree that generates a hierarchy of dark states. Importantly, these disconnected manifolds include exponentially many long-range entangled singlet dark states. The explored kinetic constraints and superradiant dynamics can be realized in neutral-atom arrays coupled to an optical cavity, and we suggest a simple and accessible witness to detect the predicted mixed-state entanglement in such experiments. Moreover, we show that entanglement generation is robust against atomic decay and collective dephasing, and should be observable under recently reported experimental conditions. Our results, thereby, offer a general framework and experimentally viable approach for the dissipative engineering of entangled dark states enhanced by superradiance.

2605.16130 2026-05-18 nlin.AO

Length-scale selection in adaptive transport networks

适应性运输网络中的长度尺度选择

Sidney Holden, Mia C. Morrell, Geoffrey Vasil, Eleni Katifori

AI总结 研究通过连续模型揭示适应性运输网络中长度尺度选择机制,发现由模式形成不稳定性驱动的各向异性结构形成,推翻传统能量景观理论。

Comments 8 pages, 4 figures

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AI中文摘要

生物和物理系统中的适应性运输网络表现出分层组织、特征通道间距和稳健的尺度关系。现有基于晶格的适应性网络模型能再现许多观察到的拓扑和导管尺度定律;然而,选择网络密度和空间间距的机制仍不明确。本文在连续框架中研究,导电性作为张量场与压力驱动流动耦合。线性化关于均匀导电状态,发现控制参数中具有-1/4优选波长尺度的有限波长不稳定性。完整方程模拟验证了分析预测,并展示了阈值以上形成的各向异性导电结构。这些结果建立了适应性运输网络形成的尺度选择原理,该原理源于模式形成不稳定性而非仅来自非凸能量景观的松弛。不稳定性机制将适应性运输系统置于更广泛的非平衡模式形成介质类别中,其中构成性运输反馈生成空间组织。除再现分层尺度定律外,该理论还预测了运输网络的固有密度和资源输送的空间尺度。

英文摘要

Adaptive transport networks in biological and physical systems exhibit hierarchical organization, characteristic channel spacing, and robust scaling relations. Existing adaptive network models, formulated on a lattice, successfully reproduce many observed topologies and conduit scaling laws; however, the mechanism that selects network density and spatial spacing remains unclear. We address this in a continuum formulation where conductivity evolves as a tensor field coupled to pressure-driven flow. Linearizing about a homogeneous conducting state, we identify a finite-wavelength instability with a $-1/4$ preferred wavelength scaling in the control parameter. Simulations of the full equations confirm the analytical predictions and demonstrate the formation of anisotropic conducting structures above threshold. These results establish a scale-selection principle for adaptive transport network formation which arises from a pattern-forming instability rather than solely from relaxation within a nonconvex energy landscape. The instability mechanism places adaptive transport systems within a broader class of nonequilibrium pattern-forming media in which constitutive transport feedback generates spatial organization. Beyond reproducing hierarchical scaling laws, the theory additionally predicts the intrinsic density of transport networks and the spatial scale of resource delivery.

2605.16128 2026-05-18 math.DS

Evaluating the skill of a geometric early warning for tipping in a rapidly forced nonlinear system

评估几何早期预警在快速强迫非线性系统临界转变中的技能

Paul D. L. Ritchie, Sneha Kachhara, Peter Ashwin

AI总结 研究通过几何早期预警评估快速强迫非线性系统临界转变的技能,对比传统方法,以大西洋经向翻转环流模型为例展示其有效性。

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AI中文摘要

非线性系统未来行为的演变可能对强迫剖面和系统内部自然波动敏感。对于速率诱导临界转变,强迫推动系统接近未来行为的盆地边界,微小强迫变化可能导致剧烈行为差异。此敏感性可能仅在特定时期存在,如强迫最快速变化时。基于临界减缓的方法在此情况下失效。本文研究几何早期预警以评估系统是否处于敏感状态,通过计算R-临界指标(即近似R-临界阈值的有号距离)来实现。后者是动态状态,融合系统和未来强迫行为的知识。本文将此方法与基于分岔诱导临界转变的早期预警对比,以大西洋经向翻转环流(AMOC)的3箱模型为例,展示在指定快速强迫下,几何早期预警在预测未来状态方面的技能,其效果优于简单阈值方法。

英文摘要

The future behavioural fate of a forced nonlinear system can depend sensitively on the forcing profile as well as natural fluctuations within the system. This is especially the case for rate-induced tipping, where the forcing pushes the system to a basin boundary of a future behaviour and small changes in the forcing can lead to drastically different eventual behaviours. This sensitivity may be present only for a limited period of time, for example when the forcing is most rapidly changing. Moreover, critical slowing down based methods fail to be informative in such cases. We investigate a geometric early warning to evaluate when a system is in such a sensitive state. This involves computing the R-tipping indicator, namely the signed distance to an approximate R-tipping threshold. The latter is a dynamic state that embeds knowledge of the system and future behaviour of the forcing. We contrast this with early warnings of bifurcation-induced tipping, where tipping is associated with passing a threshold on slow variation of forcing. As an example, we consider methods of early prediction of the future state for a 3-box model of the Atlantic Meridional Overturning Circulation (AMOC) with specified rapid forcing. We show that the skill of the geometric early warning compares favourably with simple thresholds.

2605.16125 2026-05-18 cond-mat.stat-mech nlin.CD physics.flu-dyn

Staggering domino-like blast front motion in a one-dimensional cold gas

一维冷气体中阶梯式多米诺式爆波运动

Taras Holovatch, Yuri Kozitsky, Krzysztof Pilorz, Yurij Holovatch

AI总结 研究一维冷气体中多米诺式爆波运动的机制,分析不同质量比下的动力学行为,发现特定质量比下爆波呈现阶梯式运动特性。

Comments 21 pages, 4 figures

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AI中文摘要

一维交替粒子系统广泛用于研究气体中爆波的流体动力学与牛顿动力学之间的联系。我们研究了点粒子质量为m,μ,m,μ,…(m≥μ)分布于正实轴R_+上的模型。其动力学由给最左粒子赋予正速度启动,粒子经历弹性碰撞。对于m/μ=2的情况,已知随机初始位置的动力学与欧拉流体动力学方程预测一致。本文针对非随机(通常等距)初始位置和不同m/μ值,给出该模型的动力学结果。对于m/μ=2和等距初始位置,结果与上述一致。同时发现无限多个数{M_k},当m/μ=M_k时,流体动力学行为发生剧烈变化:每个时刻仅有一个三元组m,μ,m在运动,其余粒子静止。因此,爆波以平均速度等同于初始速度呈阶梯式多米诺式运动。此精确解提供了M_k及粒子速度和位置的显式公式。

英文摘要

One-dimensional alternating particle systems are widely used to study interconnections between the hydrodynamics of blast waves in a gas-like medium and the Newtonian dynamics of its corpuscular constituents. We study the model in which point particles with masses $m,μ, m,μ,\dots, (m\geqμ)$ are distributed on the positive half-line $\mathbb{R}_{+}$. Their dynamics are initiated by giving a positive velocity to the leftmost particle; in its course, the particles undergo elastic collisions. For this model with $m/μ=2$, it has previously been established that the dynamics that start from random initial positions are consistent with predictions based on Euler's hydrodynamic equation. In particular, they have the following properties: (i) the position of the rightmost particle (shock front) evolves as $t^δ$ with $δ<1$; (ii) recoiled particles behind the front enter the negative half-axis; (iii) particles with locations $x\leq0$ move ballistically and eventually take over the total energy of the system. In this paper, we present numerical and analytical results for the dynamics of this model with nonrandom (typically equidistant) initial positions and various values of $m/μ$. For $m/μ=2$ and equidistant initial positions, our results qualitatively agree with those just mentioned. At the same time, we found an infinite family of numbers $\{\mathcal{M}_k\}$ such that, for $m/μ=\mathcal{M}_k$, the hydrodynamic behavior mentioned changes drastically to the following. At each moment, only a single triplet $m,μ, m$ is in motion, whereas all other particles are at rest. As a result, the shock front moves ballistically with an average velocity equal to the initial one. Such a `staggering domino-like' picture is obtained as an exact solution, which yields, in particular, explicit formulas for $\mathcal{M}_k$ and the particle velocities and positions.

2605.16124 2026-05-18 math.FA

Moment problems on compacts of characters of an unital commutative algebra

在单位可换代数紧致上的动量问题

Dragu Atanasiu

AI总结 本文研究了单位可换R代数上的线性泛函,给出了非负泛函在阿基米德锥上的积分表示,并解决了区间乘积上的动量问题,确定了泛函在紧致上的动量条件。

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AI中文摘要

在本文中,我们考虑了单位可换R代数上的线性泛函。我们给出了非负泛函在阿基米德锥上的积分表示,其中不假设该锥是半环或二次模块。我们还解决了区间乘积上的动量问题,并确定了泛函在紧致上的动量条件。

英文摘要

In this note we consider linear functionals on an unital commutative R-algebra. We give an integral representation of a nonnegative functional on an Archimedean cone where we do not assume that this cone is a semiring or a quadratic module. We also give a solution of the moment problem on a product of intervals and determine conditions for a functional to be a moment functional on a compact of characters.

2605.16123 2026-05-18 cond-mat.mtrl-sci

Thermal conductivity of seifertite and pyrite-type SiO$_2$: A comparative study

蛇纹石和黄铁矿型SiO₂的热导率:比较研究

Doyoon Park, Yihang Peng, Jie Deng

AI总结 本文通过分子动力学模拟计算了蛇纹石和黄铁矿型SiO₂的晶格热导率,采用Green-Kubo方法和机器学习势能函数,发现其热导率比声子准粒子方法高119%,并指出地幔中可能形成热绝缘层。

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AI中文摘要

热导率是理解行星内部动力学和演化的基本材料属性。尽管其重要性,蛇纹石和黄铁矿型SiO₂的热导率仍未知。本文利用分子动力学模拟和两种机器学习势能函数(基于SCAN和PBEsol交换-相关泛函)计算了蛇纹石和黄铁矿型SiO₂的晶格热导率,精度达到从头计算水平。此外,通过声子准粒子方法进行比较。Green-Kubo方法预测热导率比声子准粒子方法高119%,温度依赖性接近T⁻¹,因该方法能完全捕捉高温下的扩散型声子。蛇纹石到黄铁矿型相变过程中热导率下降19%,表明超地球地幔中可能形成热绝缘层。

英文摘要

Thermal conductivity is a fundamental material property that plays a crucial role in understanding the dynamics and evolution of planetary interiors. Despite its importance, the thermal conductivity of seifertite and pyrite-type SiO$_2$ remains unknown. Here, we calculate the lattice thermal conductivities of seifertite and pyrite-type SiO$_2$ using the Green-Kubo method based on molecular dynamics (MD) simulations driven by two machine learning potentials (MLPs) constructed from the SCAN and PBEsol exchange-correlation functionals, with $\textit{ab initio}$-level accuracy. To demonstrate our methodology, we also compute thermal conductivities using the phonon quasiparticle approach for comparison. Overall, the Green-Kubo method predicts up to 119 % higher thermal conductivity with a temperature dependence close to $T^{-1}$, as it fully captures diffusion-like phonons at high temperatures that are missed by the phonon quasiparticle approach. The 19 % reduction in thermal conductivity across the phase transition from seifertite to the pyrite-type phase suggests the potential formation of a thermally insulating layer in the mantle of super-Earths.

2605.16120 2026-05-18 cs.IR

MERVIN: A Unified Framework for Multimodal Event Retrieval in Vietnamese News Videos

MERVIN:一种用于越南新闻视频多模态事件检索的统一框架

Anh-Tai Pham-Nguyen, Tung-Duong Le-Duc, Anh-Duy Le, Trung-Hieu Truong-Le

AI总结 本文提出MERVIN框架,整合关键帧、转录文本和视频摘要,通过Gemini 1.5 Flash提升转录质量,利用Perception Encoder提取视觉特征,并结合越南语言模型生成文本嵌入,实现高效的多模态事件检索。

Comments Accepted to SOICT 2025

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AI中文摘要

在线视频平台的增长推动了有效、语义导向事件检索的需求。我们提出了MERVIN,一种用于越南新闻视频的统一多模态框架,整合关键帧、转录文本和视频摘要。通过Gemini 1.5 Flash提升转录质量,减少口音、背景噪音和识别错误的影响。视觉特征通过Perception Encoder提取,而越南语言模型生成文本嵌入;两者在Milvus中进行索引,实现高效的相似性检索。此外,基于React的界面允许在不同模态间进行迭代查询优化,提高语义对齐。在越南新闻视频上的实验结果展示了所提系统的有效性,MERVIN在AI Challenge HCMC 2025资格赛中获得79/88分,并在决赛轮中成功检索了每个查询的所有结果。

英文摘要

The growth of online video platforms drives the need for effective, semantically grounded event retrieval. We present MERVIN, a unified multimodal framework for Vietnamese news videos that integrates keyframes, transcripts, and video summaries. Transcript quality is enhanced via Gemini 1.5 Flash, reducing noise from accents, background sounds, and recognition errors. Visual features are extracted with Perception Encoder, while a Vietnamese language model produces textual embeddings; both are indexed in Milvus for efficient similarity-based retrieval. In addition, a React-based interface enables iterative query refinement across modalities, improving semantic alignment. Experimental results on Vietnamese news videos demonstrate the effectiveness of the proposed system, with MERVIN achieving 79 out of 88 points in AI Challenge HCMC 2025 qualification phase and successfully retrieved all results for every query in the final round.

2605.16119 2026-05-18 hep-th cond-mat.stat-mech

Boundary anomalous dimensions from BCFT: $ϕ^{3}$ theories with a boundary and higher-derivative generalizations

边界异常维数从BCFT:带有边界的ϕ³理论及其高导数推广

Yongwei Guo, Wenliang Li

AI总结 本文研究了带有边界的ϕ³理论在ε展开中的边界基本算符标度维数修正,结合共形多重集合并边界交叉对称性,推导出单场和多场情况下的结果,并推广到高导数理论。

Comments 29 pages, 1 figure

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AI中文摘要

我们考虑了自由边界共形场论在ε展开中的bulk ϕ³变形。我们确定了边界基本算符和某些边界算符展开系数的主导修正。我们的方法结合了共形多重集合并边界交叉对称性。结果涵盖了单场情况和具有S_{N+1}全局对称性的多场情况,分别与Yang-Lee模型和(N+1)态Potts模型相关。这些半无限模型描述了表面的树枝状聚合物、渗透和覆盖森林。我们还将这些结果推广到某些高导数理论。此外,我们研究了ϕ^{2n+1}理论(n>1),但仅获得了部分边界算符展开系数。

英文摘要

We consider the bulk $ϕ^3$ deformation of the free boundary conformal field theory in the $ε$ expansion. We determine the leading corrections to the scaling dimensions of boundary fundamental operators and some boundary operator expansion coefficients. Our procedure combines the conformal multiplet recombination with the boundary crossing symmetry. The results cover both the single field case and the multi-field case with $S_{N+1}$ global symmetry, which are associated with the Yang-Lee model and the $(N+1)$-state Potts model respectively. These semi-infinite models describe branched polymers, percolation, and spanning forest at a surface. We generalize these results to some higher derivative theories. In addition, we study the $ϕ^{2n+1}$ theories with $n>1$, but only obtain some boundary operator expansion coefficients.

2605.16110 2026-05-18 cond-mat.mtrl-sci cs.IT math.IT

Causation-guided mechanism identification and interpretable reduced-order modeling of damage-driving grain-boundary stress in creep

基于因果引导的机制识别与可解释降阶建模的蠕变驱动晶界应力

Weichen Kong, Yanwei Dai, Yinglin Zhang, Yinghua Liu

AI总结 本文通过结合位错攀爬影响的晶粒塑性有限元模拟与因果引导机器学习框架,识别晶界应力的关键特征并建立可解释的降阶模型,揭示了晶界几何、晶体学兼容性、蠕变应力松弛和微机械对比的耦合作用。

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AI中文摘要

晶界(GB)局部应力是多晶超合金长期蠕变损伤起始和演化的核心因素。由于GB应力响应与多种晶体学、微观结构和微机械特性之间存在高维非线性关系,仍难以识别控制GB应力的关键特性并阐明其影响机制。通过结合位错攀爬影响的晶粒塑性有限元模拟与集成的因果引导机器学习框架,其中力学指导的描述符通过因果熵分析来识别控制机制,然后被提炼成降阶回归形式以实现可解释的GB法向应力预测。在18个物理驱动的特性中,发现晶界倾角、滑移传递、与攀爬相关的Schmid型指标以及弹性模量不匹配是主导因素,揭示了界面几何、晶体学兼容性、蠕变应力松弛和微机械对比的耦合作用。识别出的特性层次和功能表示在多轴加载下仍有效,并可通过物理可解释的非局部增强扩展到三晶粒系统,当纯局部描述不足时,展示了强物理一致性和在物理条件下的稳健泛化能力。提取的候选函数也提高了多个机器学习模型类别的替代模型性能,为所识别表示的物理相关性和效率提供了证据。所提出的方法在开发可解释机器学习模型和研究微尺度非局部损伤研究中显示出强大潜力。

英文摘要

Grain-boundary (GB) local stress is central to the initiation and evolution of long-term creep damage in polycrystalline superalloys. Owing to the high-dimensional nonlinear relationships between the GB stress response and multiple crystallographic, microstructural, and micromechanical characteristics, it remains challenging to identify the key characteristics governing GB stress and to elucidate their mechanisms of influence. Dislocation-climb-affected crystal-plasticity finite-element simulations of minimal grain clusters are combined with an integrated causation-guided machine-learning framework, in which mechanics-informed descriptors are analyzed by causation entropy to identify governing mechanisms and then distilled into a reduced-order regression form for interpretable prediction of GB normal stress. Among 18 physically motivated characteristics, the GB inclination angle, the slip transmission, the climb-related Schmid-type indicator, and the elastic-modulus mismatch are found to be dominant, revealing the coupled roles of interfacial geometry, crystallographic compatibility, creep stress relaxation, and micromechanical contrast. The identified characteristics hierarchy and functional representation remain effective under multiaxial loading and can be extended to tricrystal systems through physically interpretable nonlocal augmentation when a purely local description becomes insufficient, demonstrating strong physical consistency and robust generalizability across physical conditions. The extracted candidate functions also improve surrogate-model performance across multiple machine-learning model classes, providing supporting evidence for the physical relevance and efficiency of the identified representation. The proposed methods demonstrate strong potential for the development of interpretable machine-learning models and for the study of microscale nonlocal damage.

2605.16106 2026-05-18 cond-mat.mtrl-sci

Long-range magnetic ordering and structural phase transition in disordered high-entropy spinel chromites

长程磁序和结构相变在无序高熵-spinel铬氧化物中

Sushanta Mandal, Koushik Chakraborty, Isha, Arvind Kumar Yogi, S. D. Kaushik, Sourav Marik, Tirthankar Chakraborty

AI总结 研究了Cr基高熵-spinel的温度演变,发现其在室温下以立方结构结晶,并在Néel温度以下发生反铁磁序,同时在约55K和85K时发生结构相变,高熵促进全局结构稳定,保留原始-spinel系统的长程序和对称性破缺转变。

Comments 10 pages, 7 figures

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AI中文摘要

高熵-spinel氧化物为研究熵稳定相关系统提供了良好平台,本文系统研究了Cr基高熵-spinel的结构和磁性性质。结果表明,两种系统在室温下以立方结构(空间群Fd3m)结晶。每个系统在Néel温度T_N=49 K和35 K以下发生反铁磁序。中子衍射测量证实了长程磁序的出现,具有螺旋自旋排列。两种系统分别在约55 K和85 K时从立方Fd3m结构转变为正交结构Fddd对称性。值得注意的是,尽管A位存在显著化学无序,两种系统表现出与低熵-spinel系统相似的转变行为。这种行为表明,高配位熵可能促进全局结构稳定,尽管存在局部化学无序,从而保留长程序和原始-spinel系统的特征对称性破缺转变。

英文摘要

High-entropy spinel oxides provide an excellent platform for investigating entropy-stabilized correlated systems with strong configurational disorder. In this work, we systematically study the temperature evolution of the structural and magnetic properties of Cr-based high-entropy spinels with compositions $(Mn_{0.2}Co_{0.2}Ni_{0.2}Cu_{0.2}Zn_{0.2})Cr_2O_4$ and $(Mg_{0.2}Co_{0.2}Ni_{0.2}Cu_{0.2}Zn_{0.2})Cr_2O_4$. Our results reveal that both systems crystallize in cubic structure with space group \textit{$Fd\overline{3}m$} at room temperature. Each system undergoes antiferromagnetic ordering below the Néel temperatures $ T_N$ = 49 K and 35 K, respectively. Neutron diffraction measurements confirm the emergence of long-range magnetic order with spiral spin arrangement. Both systems exhibit a structural phase transition from cubic \textit{$Fd\overline{3}m$} to orthorhombic \textit{Fddd} symmetry at approximately 55 K and 85 K, respectively. Notably, despite the significant chemical disorder at the A site, both systems undergo transitions analogous to those observed in low entropy spinel systems. This behavior suggests that high configurational entropy may promote global structural stabilization despite local chemical disorder, thereby preserving long-range orderings and the characteristic symmetry-breaking transitions of the pristine spinel systems.

2605.16105 2026-05-18 astro-ph.GA

Kinematic hints of a nuclear bar in the Milky Way

银河系中的核棒动能暗示

Karl Fiteni, Mattia C. Sormani, Victor P. Debattista, Francisco Nogueras-Lara, Rainer Schödel, Jason L. Sanders, Mathias Schultheis, Xingchen Li, Arianna Vasini, Zi-Xuan Feng, Marco Donati

AI总结 研究通过结合KMOS NSD调查的径向速度与VIRAC2的自行数据,发现银河系核星盘可能存在核棒结构,其顶点偏差显著且各向异性特征与预期相符。

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AI中文摘要

银河系拥有一种扁平的核星盘(NSD),其引力势在银河系内几百年秒范围内占据主导地位。NSD是否纯粹轴对称或包含核棒仍是一个开放问题。我们通过结合KMOS NSD调查的径向速度与VIRAC2的自行数据,构建了(v_ℓ, v_los)速度椭圆,以检测核棒的存在。在应用严格质量切割以最小化大尺度棒星污染后,我们对多个子样本测量了顶点偏差l_v和各向异性β。对于我们的主样本(|ℓ| < 0.9°, -0.4° < b < 0.25°, [Fe/H] > -0.3),我们发现显著的负顶点偏差l_v = -54.8±13.1_-14.8°,中等各向异性β=0.16±0.08_-0.05。一个限制在最内四区的子样本产生更强烈的信号,l_v = -64.3±12.1_-12.2°,β=0.38±0.12_-0.07。最大速度分散方向沿银河系经度方向,与大尺度棒主导样本观察到的方向相反。这些特征在消光驱动的不完整性、主棒污染和金属度阈值选择方面都稳健。它们与轴对称NSD或与主棒垂直的NSD不一致,但与核棒沿太阳-银河系中心线约60°-75°方向倾斜且近侧指向正经度方向的预期相符。尽管需要更大更精确的样本确认,我们的结果提供了银河系中可能核棒的首个动能迹象。

英文摘要

The Milky Way hosts a flattened nuclear stellar disc (NSD) that dominates the gravitational potential in the inner few hundred parsecs. Whether the NSD is purely axisymmetric or contains a nuclear bar remains an open question. We test for the presence of a nuclear bar using kinematic diagnostics by combining line-of-sight velocities from the KMOS NSD survey with proper motions from VIRAC2 to construct the $ (v_\ell, v_\mathrm{los}) $ velocity ellipse. After applying strict quality cuts to minimise contamination from large-scale bar stars, we measure the vertex deviation $ l_v $ and anisotropy $ β$ for several subsamples. For our primary sample ($ |\ell| < 0.9^\circ $, $ -0.4^\circ < b < 0.25^\circ $, $ \mathrm{[Fe/H]} > -0.3 $), we find a significant negative vertex deviation $ l_v = -54.8^{+13.1}_{-14.8}\,^\circ $ with moderate anisotropy $ β= 0.16^{+0.08}_{-0.05} $. A subsample restricted to the innermost four fields yields an even stronger signal with $ l_v = -64.3^{+12.1}_{-12.2}\,^\circ $ and $ β= 0.38^{+0.12}_{-0.07} $. The direction of maximum velocity dispersion is oriented along Galactic longitude, opposite to that observed in large-scale bar-dominated samples. These signatures are robust against extinction-driven incompleteness, primary-bar contamination, and the choice of metallicity threshold. They are inconsistent with an axisymmetric NSD or one oriented orthogonally to the primary bar, but match expectations for a nuclear bar oriented at $ α\approx 60^\circ $-$75^\circ$ to the Sun-Galactic-Centre line with its near side pointing toward positive Galactic longitude. While definitive confirmation awaits larger and more precise samples from upcoming surveys, our results provide the first kinematic indication of a possible nuclear bar in the Milky Way.

2605.16104 2026-05-18 q-bio.GN q-bio.QM

StateXDiff: Cell State-Contextualized Multimodal Diffusion for Single-Cell Perturbation Prediction

StateXDiff: 单细胞扰动预测的细胞状态-上下文化多模态扩散框架

Peiting Shi, Ningfeng Que, Xianzhe Huang, Xiaofei Wang, Jianzhong Jeff Xi

AI总结 StateXDiff通过整合转录组与蛋白质特征,构建多模态细胞状态表示,并利用条件扩散模型生成药物扰动特异性变化,提升单细胞扰动预测的泛化能力。

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AI中文摘要

预测药物诱导的单细胞状态变化仍是虚拟细胞建模的核心挑战,特别是在分布外(OOD)条件下。当前方法主要依赖RNA基检测,难以充分捕捉药物反应下的多样化细胞状态。此外,条件分布偏移和低信噪比常导致模型学习虚假相关性而非真实状态转换。为此,我们引入StateXDiff,一种细胞状态-上下文化多模态(X)扩散框架,用于预测单细胞对药物扰动的响应。该框架分阶段操作:首先通过整合转录组谱与推断的蛋白质特征学习解耦的多模态细胞状态表示;其次利用条件扩散模型生成扰动特异性变化。我们的方法引入虚拟多模态细胞状态,将RNA基表示与蛋白质层面上下文相结合,并引入机制感知的药物-基因模板,整合多源生物学知识以实现准确的药物表示。生成由潜在空间扩散Transformer驱动,通过质量感知的三元组约束进行正则化,包括正向药物-蛋白质对或蛋白质-药物不匹配对,并明确蛋白质可靠性加权。广泛评估表明,StateXDiff在三个具有挑战性的设置中均提升了泛化性能:未见细胞系、未见药物和组合扰动。

英文摘要

Predicting drug-induced cellular state changes at single-cell resolution remains a central challenge in virtual cell modeling, particularly under out-of-distribution (OOD) conditions. Current approaches predominantly rely on RNA-based assays, which often fail to adequately capture the diverse cellular states underlying drug responses. Moreover, conditional distribution shifts and low signal-to-noise ratios frequently cause models to learn spurious correlations rather than genuine state transitions. To address these limitations, we introduce StateXDiff, a cell State-contextualized multimodal (X) Diffusion framework for predicting single-cell responses to drug perturbations. The framework operates sequentially: first, it learns a disentangled, multimodal representation of cellular state by integrating transcriptomic profiles with inferred protein features; second, it employs a conditional diffusion model to generate perturbation-specific changes. Our approach introduces a Virtual Multimodal Cell State, which augments RNA-based representations with protein-level context, and a Mechanism-aware Drug-Gene Template, which consolidates multi-source biological knowledge for accurate drug representation. Generation is driven by a latent-space diffusion Transformer, regularized through quality-aware triplet constraints, including positive drug-protein pairs or protein-drug mismatched pairs, and explicit protein-reliability weighting. Extensive evaluation demonstrates that StateXDiff consistently enhances generalization performance across three challenging settings: unseen cell lines, unseen drugs, and combinatorial perturbations.

2605.16102 2026-05-18 math.NA cs.NA

On the Convergence of a Spline Collocation Method for Nonlinear Fractional Boundary Value Problems with the Riesz-Caputo Operator

关于非线性分数边值问题的样条离散方法收敛性的研究

Chiara Sorgentone, Enza Pellegrino, Francesca Pitolli

AI总结 本文研究了涉及Riesz-Caputo算子的非线性分数边值问题,通过积分表示证明解的存在唯一性,并提出B-样条离散方法进行数值逼近,结合理论分析与实验验证其收敛性。

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AI中文摘要

分数边值问题常用于建模具有记忆效应和异常扩散特性的复杂系统和过程。本文考虑涉及Riesz-Caputo算子的分数边值问题,该算子特别适合建模具有对称扩散效应的物理现象。我们提供了解的积分表示,以证明分数微分问题的存在性和唯一性。我们引入B-样条离散方法来近似问题的解,并提供收敛性分析,包括理论见解和数值实验。

英文摘要

Fractional boundary value problems are often used to model complex systems and processes characterized by memory effects and anomalous diffusion. In this paper, we consider fractional boundary value problems involving the Riesz-Caputo operator, which is particularly suited for modeling physical phenomena exhibiting symmetric diffusive effects. We provide an integral representation of the solution to prove existence and uniqueness of the fractional differential problem. We introduce a B-spline collocation method to approximate the solution of the problem and provide a convergence analysis, with both theoretical insights and numerical experiments.

2605.16101 2026-05-18 quant-ph physics.hist-ph

Quantum Measurement without Ontology

量子测量无本体论

Richard Healey

AI总结 本文探讨量子测量与本体论的关系,指出测量结果的客观性在量子力学中面临挑战,但方法论规范仍维持测量结果的客观性。

Comments To appear in Coherentist Approaches to Quantum Metrology, Routledge Studies in the Philosophy of Mathematics and Physics, forthcoming

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AI中文摘要

测量是重要的科学活动。在大多数科学中,包括经典物理,测量可以被视为了解物理世界并以数值表示结果的方式。否定定理显示量子可观测量的测量不同于此:记录的结果通常是在量子测量中被创造而非揭示,因此可观测量先前值的客观事实不存在。其他否定定理显示,单位ary量子理论通常无法解释或甚至代表一个独特的记录结果,从而威胁该结果的客观性。然而,量子物理实践中固有的方法论规范仍然确立了量子测量唯一记录结果的客观性,以及科学家所认为代表的世界非量子特征的客观性。

英文摘要

Measurement is an important scientific activity. In most of science, including classical physics, is may be understood as a way of finding out about the physical world and representing the results numerically. No-go theorems show that measurement of quantum observables is not like that: the recorded outcome is typically created rather than revealed in a quantum measurement, in which case there is no objective fact about the observable's prior value. Other no-go theorems show that unitary quantum theory can generally neither explain nor even represent a unique recorded outcome, thereby threatening that outcome's objectivity. Methodological norms inherent in quantum physical practice nevertheless institute the objectivity, not only of unique recorded outcomes of quantum measurements, but also of non-quantum features of the world that physicists and other scientists take their models to represent.

2605.16100 2026-05-18 physics.atom-ph

Multipole blackbody radiation shift in Rydberg atoms

多极黑体辐射位移在瑞利原子中的作用

R. M. Potvliege

AI总结 研究高温下瑞利态受热辐射影响的能量位移中 retardation 的作用,发现非偶极位移在约2.5倍特征温度时主导偶极位移,并需考虑电四极热位移与反磁热位移的同等量级。

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AI中文摘要

我们研究了退相干在热辐射引起瑞利态能量位移中的作用,重点研究温度高于预期偶极近似适用的温度情况。正如Farley和Wing [Phys. Rev. A 23, 2397 (1981)] 所预见的,当温度达到 α mc²/(3k_B n²) 时,退相干需在计算中考虑,其中n是所考虑态的主量子数,m是电子质量,k_B 是玻尔兹曼常数。对应的非偶极位移在约2.5倍特征温度时主导偶极位移。我们还表明,电四极热位移与反磁热位移量级相当,因此在后者相关的情况下需予以考虑。

英文摘要

We study the role of retardation in the energy shift of Rydberg states induced by thermal radiation, focusing on the case of temperatures higher than those for which the electric-dipole approximation is expected to apply. As anticipated by Farley and Wing [Phys. Rev. A {\bf 23}, 2397 (1981)], retardation needs to be taken into account in calculations of this energy shift at and above the temperature $α\, mc^2/(3k_{\rm B}\,n^2)$, where $n$ is the principal quantum number of the state considered, $m$ is the mass of the electron and $k_{\rm B}$ is Boltzmann constant.The corresponding non-dipole shift dominates the electric-dipole shift at about 2.5 times that characteristic temperature. We also show that the electric-quadrupole thermal shift is of the same order of magnitude as the diamagnetic thermal shift and would thus need to be taken into account in the circumstances where the latter is relevant.