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2606.08801 2026-06-09 cond-mat.stat-mech 新提交

Fluctuation-stable generalized entropy probes of spectral heterogeneity

谱异质性的涨落稳定广义熵探针

Arpita Goswami

AI总结 本文提出涨落稳定性框架,证明广义熵在q>1时抑制弱振幅谱涨落,并引入熵梯度磁化率χ_q作为谱异质性探针,通过Aubry-André模型区分均匀局域化转变与迁移率边共存。

Comments 9 pages, 3 figures

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AI中文摘要

广义熵度量广泛用于表征局域化和多重分形,且经验发现q>1区域通常表现出更好的数值稳定性和更清晰的标度行为。本文为广义熵诊断建立了一个涨落稳定性框架,并表明弱振幅谱涨落在q<1时被放大,在q>1时被抑制,从而为物理上稳健的q>1区域提供了理论基础。热力学标度分析进一步识别出超过临界阈值的渐近稳定区域。作为应用,我们引入熵梯度磁化率χ_q作为谱异质性的粗粒化探针。利用Aubry-André和广义Aubry-André模型,我们证明χ_q能清晰区分均匀局域化转变与迁移率边共存区域。我们的结果确立了涨落稳定性作为准周期系统中广义熵诊断的指导原则。

英文摘要

Generalized entropy measures are widely used to characterize localization and multifractality, and the regime \(q>1\) is often empirically found to exhibit improved numerical stability and cleaner scaling behavior. Here, we develop a fluctuation-stability framework for generalized entropy diagnostics and show that weak-amplitude spectral fluctuations are amplified for \(q<1\) and suppressed for \(q>1\), thereby providing a theoretical basis for the physically robust \(q>1\) regime. A thermodynamic scaling analysis further identifies an asymptotically stable regime beyond a critical threshold. As an application, we introduce the entropy-gradient susceptibility \(χ_q\) as a coarse-grained probe of spectral heterogeneity. Using the Aubry-André and generalized Aubry-André models, we demonstrate that \(χ_q\) sharply distinguishes homogeneous localization transitions from mobility-edge coexistence regimes. Our results establish fluctuation stability as a guiding principle for generalized entropy diagnostics in quasiperiodic systems.

2606.08798 2026-06-09 math.DS 新提交

State-Feedback Control of Logistic-Based Gene Regulatory Networks: Closed-Form Lyapunov Certificates, Monostabilization, and Delay-Uniform Stability

基于逻辑斯蒂的基因调控网络的状态反馈控制:闭环李雅普诺夫证书、单稳态化与延迟一致稳定性

Ismail Belgacem

AI总结 针对逻辑斯蒂基因调控网络,提出加性状态反馈框架,证明全局指数稳定性条件,给出闭环形式收敛速率,并实现双稳态开关的单稳态化与延迟一致稳定性。

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AI中文摘要

基因调控网络(GRN)是治疗和合成生物学控制的高价值目标。经典的Hill模型存在结构缺陷:当激活子缺失时,生产项消失,导致乘法驱动下的可控性丧失和加法驱动下的网络耦合崩溃——而这正是生物操作最常发生的区域。基于逻辑斯蒂函数作为稳健的Hill替代,我们为基于逻辑斯蒂的GRN开发了一个加性状态反馈框架,并附带两个标量结果。一个前馈加比例定律将任何正设定点转化为闭环平衡点,无论非受控动力学如何。我们证明了在Gershgorin增益界下的局部指数稳定性,并通过基于逻辑斯蒂扇形界的公共二次李雅普诺夫函数,在显式条件$(γ_1+K_1)(γ_2+K_2)>κ_1κ_2λ^2/64$下证明了全局指数稳定性,并给出了闭环形式速率。一个对角李雅普诺夫证书$P=\mathrm{diag}(B,A)$给出了显式的稳定时间界(在模拟的1%以内)和一个ISS最终界估计。我们进一步为双稳态自激活开关建立了参数一致的单稳态化预算$K^{*}=κλ/4-γ$,以及一个Halanay型延迟一致全局指数稳定性定理,条件为$γ+K>κλ/4$,并给出了双边闭环形式速率界。与Hill对应物的数值比较证实了在标称范围内的稳健跟踪,同时暴露了在正象限边界附近的结构性分歧:当$x_{d,1}\to0$时,Hill耦合$|[J_f]_{21}|=Θ(x_{d,1}^{n-1})\to0$,而逻辑斯蒂耦合保持严格正。

英文摘要

Gene regulatory networks (GRNs) are high-value targets for therapeutic and synthetic-biology control. Classical Hill models carry a structural defect: the production term vanishes when the activator is absent, causing loss of controllability under multiplicative actuation and a collapse of network coupling under additive actuation -- precisely where biological operation is most common. Building on logistic functions as robust Hill alternatives, we develop an additive state-feedback framework for logistic-based GRNs, with two companion scalar results. A feedforward-plus-proportional law turns any positive setpoint into a closed-loop equilibrium, regardless of the uncontrolled dynamics. We prove local exponential stability under a Gershgorin gain bound and, via a common quadratic Lyapunov function built on the logistic sector bound, global exponential stability under the explicit condition $(γ_1+K_1)(γ_2+K_2)>κ_1κ_2λ^2/64$, with a closed-form rate. A diagonal Lyapunov certificate $P=\mathrm{diag}(B,A)$ yields an explicit settling-time bound (within $1\%$ of simulation) and an ISS ultimate-bound estimate. We further establish a parameter-uniform monostabilization budget $K^{*}=κλ/4-γ$ for bistable self-activation switches, and a Halanay-type delay-uniform global exponential stability theorem under $γ+K>κλ/4$, with two-sided closed-form rate bounds. Numerical comparison with the Hill counterpart confirms robust tracking in the nominal range while exposing the structural divergence near the boundary of the positive orthant: the Hill coupling $|[J_f]_{21}|=Θ(x_{d,1}^{n-1})\to0$ as $x_{d,1}\to0$, whereas the logistic coupling stays strictly positive.

2606.08796 2026-06-09 cs.CE 新提交

A Non-Overlapping Schwarz Hybrid Finite Element-Neural Operator Framework for Solid Mechanics on Irregular Domains

不规则区域固体力学的一种非重叠Schwarz混合有限元-神经算子框架

Wei Wang, Abhinav Gupta, Haihui Ruan, Somdatta Goswami

AI总结 提出非重叠Schwarz交替法结合Neumann-Dirichlet界面交换,消除重叠层并减少内迭代;Point-DeepONet处理不规则几何,从位移算子解析导出应变应力算子,降低参数量并保证力学一致性。

Comments 40 Pages,19 figures

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AI中文摘要

有限元方法是固体力学仿真的基准,但对于局部非线性、细尺度特征或长时间动态演化问题,其计算成本变得过高。在我们早期的有限元-神经算子混合框架[1]中,通过具有Dirichlet-Dirichlet界面交换的重叠区域分解,将物理信息深度算子网络与有限元求解器耦合,加速了密集子域同时保持其他区域的有限元保真度。仍存在两个限制:重叠公式需要冗余的界面计算,增加了内Schwarz迭代次数;卷积特征提取器将神经算子子域限制在结构化网格上,排除了不规则几何。本文采用具有Neumann-Dirichlet界面交换的非重叠Schwarz交替方法替代,将牵引力从神经算子传递到有限元而非位移。这消除了重叠层并减少了内Schwarz迭代,同时在所有测试时间范围内保持有界误差累积。对于任意形状的子域,Point-DeepONet在非结构化有限元点云上运行而无需插值,将其扩展到非凸和不规则几何。应变和应力算子通过运动学方程从位移算子解析导出,而非作为独立网络,从而减少可训练参数集并通过构造强制执行力学一致性。该框架在三个基准上得到验证:静态线弹性、准静态超弹性和具有规则及不规则几何的弹性动力学。这些结果建立了一种几何灵活、参数高效且收敛稳定的非重叠有限元-神经算子耦合范式,为大规模动态固体力学中基于物理和算子学习的混合求解器提供了途径。

英文摘要

Finite element (FE) methods are the benchmark for solid mechanics simulations, yet their computational cost becomes prohibitive for problems with localised nonlinearities, fine-scale features, or long-time dynamic evolution. In our earlier FE-neural operator (FE-NO) hybrid framework [1], physics-informed deep operator networks were coupled with FE solvers through overlapping domain decomposition with Dirichlet-Dirichlet interface exchange, accelerating intensive subdomains while preserving FE fidelity elsewhere. Two limitations remained: the overlapping formulation required redundant interface computations that increased inner Schwarz iteration counts, and the convolutional feature extractor restricted the NO subdomain to structured grids, precluding irregular geometries. A non-overlapping Schwarz alternating method with Neumann-Dirichlet interface exchange replaces it, transmitting traction from the NO to FE rather than displacement. This eliminates the overlap layer and reduces inner Schwarz iterations while maintaining bounded error accumulation across all tested time horizons. For arbitrarily shaped subdomains, a Point-DeepONet operates on unstructured FE point clouds without interpolation, extending it to non-convex and irregular geometries. Strain and stress operators are derived analytically from the displacement operators via kinematic equations, rather than as independent networks, reducing trainable parameter sets while enforcing mechanical consistency by construction. The framework is validated on three benchmarks: static linear elasticity, quasi-static hyperelasticity, and elastodynamics with regular and irregular geometries. These results establish a non-overlapping FE-NO coupling paradigm that is geometry-flexible, parameter-efficient, and convergence-stable, providing a pathway for hybrid physics-based and operator-learning solvers in large-scale dynamic solid mechanics.

2606.08794 2026-06-09 quant-ph cond-mat.dis-nn physics.chem-ph 新提交

Graph Neural Networks for Fast Operator Selection in Adaptive VQE

用于自适应VQE中快速算子选择的图神经网络

Javad Vahedi, Hadi H. Arefi

AI总结 提出图神经网络策略,从相互作用图和状态可观测量直接预测纠缠算子,替代梯度扫描,大幅降低自适应VQE的经典成本。

Comments 15 pages, 7 figures

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AI中文摘要

自适应变分量子算法如ADAPT-VQE通过基于梯度准则从池中迭代选择算子来构建定制化拟设。虽然这避免了过大的参数空间,但重复扫描整个池会产生与池大小线性相关的经典成本——对于长程相互作用或大算子集的系统,这是一个主要瓶颈。在这里,我们将自适应算子选择重新表述为基于图的决策问题,并引入一种图神经网络(GNN)策略,该策略直接从相互作用图和状态可观测量预测下一个纠缠算子。训练数据来自无序长程自旋链的精确模拟,使用梯度幅度作为监督信号。学习到的策略准确地再现了贪婪梯度选择规则的主导结构,显著优于仅基于相互作用强度的启发式方法。集成到变分量子本征求解器(VQE)工作流中,这种GNN-VQE方法在实现接近标准ADAPT-VQE的能量误差的同时,大幅减少了全池梯度评估。为了测试超出自旋模型的可迁移性,我们在小型活性空间分子基准(LiH和BeH$_2$)上评估了该策略。我们发现GNN作为候选列表生成器非常有效:仅对少数GNN提出的候选进行精确重新评分,就能恢复接近神谕的展开行为,同时仅搜索池的一小部分。这些结果表明,自适应电路构建包含可学习的结构,可用于加速变分量子算法。

英文摘要

Adaptive variational quantum algorithms like ADAPT-VQE construct tailored ansätze by iteratively selecting operators from a pool using gradient-based criteria. While this avoids oversized parameter spaces, repeatedly scanning the full pool incurs a classical cost that scales linearly with pool size-a major bottleneck for systems with long-range interactions or large operator sets. Here, we reformulate adaptive operator selection as a graph-based decision problem and introduce a graph neural network (GNN) policy that predicts the next entangling operator directly from the interaction graph and state-dependent observables. Training data are generated from exact simulations of disordered long-range spin chains, using gradient magnitudes as supervision signals. The learned policy accurately reproduces the dominant structure of the greedy gradient-based selection rule, significantly outperforming heuristics based solely on interaction strength. Integrated into a variational quantum eigensolver (VQE) workflow, this GNN-VQE approach achieves energy errors close to standard ADAPT-VQE while drastically reducing full-pool gradient evaluations. To test transferability beyond spin models, we evaluate the policy on small active-space molecular benchmarks (LiH and BeH_$2$). We find the GNN is highly effective as a shortlist generator: exact rescoring over just a few GNN-proposed candidates recovers near-oracle rollout behavior while searching only a small fraction of the pool. These results demonstrate that adaptive circuit construction contains learnable structure that can be exploited to accelerate variational quantum algorithms.

2606.08789 2026-06-09 math-ph math.MP 新提交

Elastodynamics from a variational standpoint: integral equalities and inequalities

从变分角度看弹性动力学:积分等式与不等式

Yury Grabovsky, Lev Truskinovsky

AI总结 本文推广诺特定理到非线性弹性动力学中的冲击解,得到包含动能和弹性能的新积分关系,并证明在热力学允许的解中,经典等式变为不等式,且动能可从动态存储的弹性能表达式中完全消除。

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AI中文摘要

众所周知,非线性弹性动力学方程的解(作用泛函的极值)可能形成冲击。我们将艾米·诺特的经典方法推广到这类奇异极值,并在变分法中推导出适当广义的积分关系。我们将它们应用于带冲击的弹性动力学极值,得到涉及动能和弹性能的新积分关系。对于对应双曲欧拉-拉格朗日方程的热力学允许(熵)解的极值,表征诺特变分方法的经典等式预期地变为不等式。我们表明,相当引人注目的是,尽管材料速度在完全惯性能量再分布过程中起关键作用,但即使在存在冲击的情况下,动能也可以从动态存储的弹性能表达式中完全消除。

英文摘要

As it is well known, solutions of equations of nonlinear elastodynamics, representing extremals of the action functional, can form shocks. We adapt the classical approach of Emmy Noether to such singular extremals and derive the appropriately generalized integral relations within Calculus of Variations. We apply them to elastodynamical extremals with shocks, obtaining new integral relations involving kinetic and elastic energies. For the extremals representing thermodynamically admissible (entropy) solutions of the corresponding hyperbolic Euler-Lagrange equations, the classical equalities, characterizing the variational approach of Noether, expectedly transform into ineqalities. We show that, rather remarkably, despite the crucial role of material velocity in the fully inertial energy redistribution processes, the corresponding kinetic energy can be completely eliminated from the expression for the dynamically stored elastic energy, even in the presence of shocks.

2606.08787 2026-06-09 hep-ph 新提交

Connected Sequential Bargmann Invariants and CP-Sensitive Geometric Correlation Structures in Neutral Meson Systems

连通顺序Bargmann不变量与中性介子系统中的CP敏感几何关联结构

Swarup Sangiri

AI总结 基于Bargmann不变量框架,引入连通顺序四阶不变量,通过投影态直接重叠关联两衰变道,定义重相位不变比以量化关联,揭示小CP破坏下的标度行为与几何性质。

Comments 19 pages, 1 figure

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AI中文摘要

我们在Bargmann不变量框架下研究了关联中性介子系统中的连通顺序几何结构。基于先前发展的涉及衰变投影条件态的三阶和四阶重相位不变几何结构,我们引入了一个连通顺序四阶Bargmann不变量,其中与两个衰变道相关的衰变投影态通过相应投影态之间的直接重叠连接。这种构造在循环重叠链中包含了显式的投影-投影关联。连通顺序不变量编码了衰变投影态之间的几何关系,从而扩展了为关联中性介子系统发展的几何关联框架。为了表征所得几何结构,我们定义了重相位不变比,用于量化连通顺序关联,并与先前研究的非连通几何关联进行直接比较。利用标准重相位不变干涉参数以及小不对称展开,在小CP破坏区域内分析了这些量的行为。我们表明,连通顺序比表现出由混合不对称和相对干涉相位对齐共同控制的特征标度行为,导致与非连通结构不同的几何标度性质。我们进一步讨论了连通顺序不变量的几何解释及其与关联中性介子系统可能的相关性。所得框架扩展了与中性介子混合和衰变相关的Bargmann不变量几何关联的层次结构,为CP敏感干涉现象提供了互补的几何视角。

英文摘要

We investigate connected sequential geometric structures in correlated neutral meson systems within the framework of Bargmann invariants. Building upon previously developed third- and fourth-order rephasing-invariant geometric structures involving decay-projected conditional states, we introduce a connected sequential fourth-order Bargmann invariant in which the decay-projected states associated with two decay channels are linked through a direct overlap between the corresponding projected states. This construction incorporates explicit projection-projection correlations within the cyclic overlap chain. The connected sequential invariant encodes the geometric relation between decay-projected states, thereby extending the geometric correlation framework developed for correlated neutral meson systems. To characterize the resulting geometric structures, we define rephasing-invariant ratios that quantify connected sequential correlations and provide a direct comparison with the previously studied disconnected geometric correlations. The behavior of these quantities is analyzed in the regime of small CP violation using the standard rephasing-invariant interference parameters together with a small-asymmetry expansion. We show that the connected sequential ratios exhibit characteristic scaling behaviors governed by both mixing asymmetry and relative interference-phase alignment, leading to geometric scaling properties distinct from those of the disconnected structures. We further discuss the geometric interpretation of the connected sequential invariants and their possible relevance to correlated neutral meson systems. The resulting framework extends the hierarchy of Bargmann invariant geometric correlations associated with neutral meson mixing and decay, providing a complementary geometric perspective on CP-sensitive interference phenomena.

2606.08786 2026-06-09 stat.ME 新提交

Inference for Balance in Dynamic Signed Networks

动态符号网络中平衡性的推断

Ergan Shang, Yuan Zhang, Weijing Tang

AI总结 针对动态符号网络,提出非参数推断方法估计指定时间点的结构平衡度,采用核平滑估计器利用时间平滑性,并基于Edgeworth展开建立高阶分布近似,理论证明时间平滑可降低稀疏网络中的观测噪声方差。

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AI中文摘要

符号网络由正负关系组成,结构平衡理论为理解其全局张力结构提供了重要的概念框架。现有统计方法主要关注评估单个观测网络中的平衡性经验证据,而许多现实世界的符号关系随时间演化。本文针对动态符号网络,在指定时间点对结构平衡的总体程度进行非参数推断,目标时间可能观测到也可能未观测到快照。我们考虑一个动态符号图模型,其中边的形成和符号的生成均由随时间平滑变化的图函数控制。为利用时间平滑性,我们构建了一个核平滑估计器,从目标时间点附近的快照中借用信息。我们的理论分析建立了一个学生化推断程序,并基于Edgeworth展开给出了高阶分布近似,表明时间平滑通过减少观测噪声的方差(直至平滑偏差和时间离散化误差)来改进稀疏网络中的推断。通过大量模拟研究和对政治科学中动态国际关系网络的应用,我们展示了所提方法的有限样本性能和实际效用。

英文摘要

Signed networks consist of both positive and negative relations, and structural balance theory provides an important conceptural framework for understanding their global tension structure. While existing statistical methods mainly focus on assessing empirical evidence of balance in a single observed network, many real-world signed relations evolve over time. This paper develops nonparametric inference for the population degree of structural balance at specified time points in dynamic signed networks, where the target time may or may not coincide with an observed snapshot. We consider a dynamic signed graphon model in which both edge formation and sign generation are governed by smoothly time-varying graphon functions. To exploit temporal smoothness, we construct a kernel-smoothed estimator that borrows information from snapshots near the target time point. Our theoretical analysis establishes a studentized inference procedure and a higher-order distributional approximation based on Edgeworth expansion, showing that temporal smoothing improves inference in sparse networks by reducing variance of observation noise, up to smoothing bias and time-discretization errors. We demonstrate the finite-sample performance and practical usefulness of the proposed method through extensive simulation studies and an application to a dynamic international relation network in political science.

2606.08785 2026-06-09 physics.class-ph 新提交

Magnetic Field Applied to the Classical Hydrogen Atom Treated in Classical Electrodynamics with Classical Zero-Point Radiation

经典电动力学与经典零点辐射处理下的经典氢原子外加磁场

Timothy H. Boyer

AI总结 研究外加磁场下经典氢原子与经典零点辐射的共振条件,解释斯特恩-格拉赫实验和塞曼效应。

Comments 13 pages

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AI中文摘要

将外加磁场应用于经典电磁理论(包括经典电磁零点辐射)处理的经典氢原子。在之前的一篇文章中,由于电子周期轨道与随机经典零点辐射之间的共振,电子的每个作用变量的平均值表现为离散值,对应于旋转群的表示。这里表明,在存在磁场的情况下,由于共振,电子的经典轨道运动仅当轨道取向与磁场方向所成角度取整数值(但排除 m=0 取向,即磁场平行于电子轨道平面)时才与随机经典零点辐射共振。给出了斯特恩-格拉赫结果和塞曼效应的经典电磁解释。

英文摘要

An external magnetic field is applied to the classical hydrogen atom treated in classical electromagnetic theory including classical electromagnetic zero-point radiation. In an earlier article, it was shown that the average value of each of the electron's action variables appears as a discrete value, corresponding to a representation of the rotation group, because of resonance between the periodic orbit of the electron and the random classical zero-point radiation. Here it is shown that, in the presence of a magnetic field and because of resonance, the classical orbital motion of the electron is in resonance with random classical zero-point radiation only for orientations of the orbit which take integer values for the angle made with the direction of the magnetic field, but excluding the m=0 orientation where the magnetic field is parallel to the orbital plane of the electron. Classical electromagnetic explanations are given for the Stern-Gerlach result, and for the Zeeman effect.

2606.08784 2026-06-09 quant-ph 新提交

Randomized simulation of quantum channels using small ancilla

使用小辅助系统的量子信道随机模拟

Marcin Kotowski, Michał Kotowski

AI总结 研究利用小辅助系统通过经典随机化和输出失败标志实现量子信道的概率精确模拟,证明单信道的成功概率与辅助维度的关系,并给出最优性证明。

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AI中文摘要

我们研究使用小辅助系统通过经典随机化和输出失败标志的后选择来实现量子信道的问题。该模拟是概率性的,但在成功时是精确的。我们证明,任何在 $d$ 维系统上的单信道都可以用辅助维度 $k$ 和成功概率 $\Omega(\frac{k}{\log d})$ 来模拟。等价地,每个 $n$ 量子比特上的单信道都可以仅使用 $O(\log n)$ 个辅助量子比特以恒定成功概率模拟。我们通过构造一族信道来证明这种权衡是最优的,这些信道的成功概率不能优于 $O(\frac{k}{\log d})$。我们还表明,高度非交换信道类(包括随机信道)仅需一个辅助量子比特即可实现恒定成功概率的模拟。我们进一步证明,这种模拟模型对于强非单信道必然失败,并讨论了涉及适应性的可能扩展。在技术方面,我们依赖于基于分区的协议和矩阵浓度不等式,包括 Bandeira、Boedihardjo 和 van Handel 最近对非交换 Khintchine 不等式的改进。

英文摘要

We study the problem of implementing a quantum channel using a small ancilla with classical randomization and postselection on an output failure flag. The simulation is probabilistic, but exact conditioned on success. We prove that any unital channel on a $d$-dimensional system can be simulated with ancilla dimension $k$ and success probability $Ω(\frac{k}{\log d})$. Equivalently, every unital channel on $n$ qubits can be simulated with constant success probability using only $O(\log n)$ ancillary qubits. We show that this tradeoff is best possible by constructing a family of channels which cannot be simulated with success probability better than $O(\frac{k}{\log d})$. We also show that the class of \textit{highly noncommutative} channels, which includes random channels, admits constant-success simulation with just a single ancillary qubit. We further show that this model of simulation necessarily fails for strongly non-unital channels and discuss possible extensions involving adaptivity. On the technical side we rely on a partition-based protocol and matrix concentration inequalities, including the recent refinement of noncommutative Khintchine inequalities due to Bandeira, Boedihardjo and van Handel.

2606.08782 2026-06-09 astro-ph.GA 新提交

JWST Absorption-Line Analysis of UV-Bright Galaxies at $z=7.2-10.6$: Early Chemical Enrichment Traced by C, O, Mg, Al, Si, and Fe

JWST对$z=7.2-10.6$紫外亮星系的吸收线分析:C、O、Mg、Al、Si和Fe示踪的早期化学增丰

Minami Nakane, Masami Ouchi

AI总结 利用JWST/NIRSpec中分辨率光谱分析8个高红移紫外亮星系的冷气体吸收线,发现5个星系有低电离态吸收线,通过拟合覆盖因子和柱密度推导化学丰度比,表明两个$z\sim7$星系已高度富Fe,且无奇偶效应,支持Ia型超新星起源。

Comments 22 pages, 11 figures, submitted to ApJ

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AI中文摘要

我们利用从档案数据中均匀选取的深JWST/NIRSpec中分辨率光谱,研究了8个亮($-21.9<M_\mathrm{UV}<-20.5$)星系在$z=7.2-10.6$处的紫外吸收线,这些谱线追踪冷气体。我们在5个星系中识别出多条低电离态物种(LIS)的吸收线,而其余3个星系仅有一个或没有显著探测。平均LIS等值宽度$\mathrm{EW_{LIS}}$表明,在致密($r_\mathrm{e}\lesssim 100$ pc)、具有高$L_\mathrm{Hβ}/L_\mathrm{UV}$和高$Σ_\mathrm{SFR}$的星系中吸收线较弱,暗示由于强烈恒星形成或核活动导致的吸收线抑制。我们同时拟合多条LIS线,同时考虑覆盖因子$C_f$和柱密度$N$,发现这5个星系遵循局域$C_f$-$N$关系。通过LIS线拟合,我们推导了化学丰度比。这5个星系在[Si/O]-[C/O]和[Fe/Si]-[Al/Si]平面上的丰度比与阻尼Ly$α$(DLA)系统相似,表明其吸收气体与DLA类似。我们发现两个$z\sim 7$的星系已经高度富Fe,$\mathrm{[Fe/Si]}\simeq -0.2$,接近太阳丰度比。虽然高Fe增丰可能源于早期Ia型超新星(SNe Ia)或对不稳定超新星(PISNe),但这两个星系也显示出$\mathrm{[Al/Si]}\sim0$,没有PISNe预期的强奇偶效应特征,因此倾向于SNe Ia。

英文摘要

We investigate UV absorption lines tracing cool gas in eight bright ($-21.9<M_\mathrm{UV}<-20.5$) galaxies at $z=7.2-10.6$ using deep JWST/NIRSpec medium-resolution spectra homogeneously selected from archival data. We identify multiple absorption lines of low-ionization species (LIS) in five galaxies, while the remaining three show only one or no significant detections. The average LIS equivalent widths $\mathrm{EW_{LIS}}$ indicate weaker absorption lines in compact ($r_\mathrm{e}\lesssim 100$ pc) galaxies with high $L_\mathrm{Hβ}/L_\mathrm{UV}$ and $Σ_\mathrm{SFR}$, suggestive of absorption-line suppression due to intense star formation or nuclear activity. We simultaneously fit multiple LIS lines, accounting for both covering fraction $C_f$ and column density $N$, and find that the five galaxies follow the local $C_f$-$N$ relation. Through the LIS-line fitting, we derive chemical abundance ratios. The five galaxies have abundance ratios similar to those of damped Ly$α$ (DLA) systems in the [Si/O]-[C/O] and [Fe/Si]-[Al/Si] planes, suggesting that their absorbing gas is similar to that of DLAs. We find that two galaxies at $z\sim 7$ are already highly Fe-enriched, with $\mathrm{[Fe/Si]}\simeq -0.2$, near the solar abundance ratio. While the high Fe enrichment may originate from early Type-Ia supernovae (SNe Ia) or pair-instability supernovae (PISNe), these two galaxies also show $\mathrm{[Al/Si]}\sim0$, with no signature of the strong odd-even effect expected from PISNe, favoring SNe Ia.

2606.08778 2026-06-09 astro-ph.GA astro-ph.SR 新提交

From filaments to clumps: filament properties with synthetic Herschel observations

从纤维到团块:基于合成赫歇尔观测的纤维性质

Zhen-Xing Ma, Zu-Jia Lu

AI总结 利用3D数值模拟的合成赫歇尔观测和FILFINDER算法,分析8832条纤维的物理性质及其与嵌入团块的关系,发现纤维承载了94%的团块和93%的恒星。

Comments 19 pages, 13 figures, Accepted for publication in ApJ

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AI中文摘要

系统性的纤维巡天已被用于研究其性质及其与恒星形成过程的关系。本文利用源自3D数值模拟的合成赫歇尔观测计算柱密度图,然后使用\texttt{FILFINDER}算法识别纤维。我们获得了包含8,832条纤维的大样本,并将其进一步分解为110,193个分支。我们表征了这些纤维结构的物理性质,并探索了它们与嵌入团块的相关性。此外,我们直接将合成结果与赫歇尔红外银河平面巡天(Hi-GAL)的32,059条纤维观测星表进行比较。结果表明,纤维在恒星形成过程中起核心作用,承载了合成观测中94%的团块和3D数值模拟中93%的恒星。承载团块的纤维具有更高的中值柱密度($1.1\times10^{21}\,\rm{cm}^{-2}$),而不含团块的纤维中值柱密度为$3.8\times10^{20}\,\rm{cm}^{-2}$。我们发现合成纤维质量和长度的幂律分布,幂律指数分别为$\alpha_{\rm M}=-0.86$和$\alpha_{\rm L} = -1.71$。我们还发现纤维密度与背景密度的关系为$N_{\rm{fs}} \propto N_{\rm{bs}}^{0.78}$。从二维合成观测中测得的纤维性质与Hi-GAL巡天中的纤维性质定性一致。

英文摘要

Systematic surveys of filaments have been conducted to study their properties and their relationship to the process of star formation. In this paper, we use synthetic Herschel observations derived from 3D numerical simulations to compute column density maps, then use the \texttt{FILFINDER} algorithm to identify filaments. We obtain a large sample of 8,832 filaments that we further decompose into 110,193 branches. We characterize the physical properties of these filamentary structures and explore their correlations with embedded clumps. Furthermore, we directly compare our synthetic results with an observational catalogue of 32,059 filaments from the Herschel Infrared Galactic Plane Survey (Hi-GAL). Our results show that filaments are central to the star formation process, hosting $94\%$ of clumps from synthetic observations and $93\%$ of stars from our 3D numerical simulation. Filaments that host clumps have higher median column densities ($1.1\times10^{21}\,\rm{cm}^{-2}$) than those without ($3.8\times10^{20}\,\rm{cm}^{-2}$). We find power-law distributions for our synthetic filament masses and lengths, with power-law indexes of $α_{\rm M}=-0.86$ and $α_{\rm L} = -1.71$, respectively. We also find that the relation between the density of filaments and the background density is $N_{\rm{fs}} \propto N_{\rm{bs}}^{0.78}$. The measured properties of the filaments from the 2D synthetic observations are qualitatively consistent with those of the filaments from the Hi-GAL survey.

2606.08776 2026-06-09 math.PR 新提交

Approximation of certain stochastic integrals with anticipating integrands

某些带预期被积函数的随机积分的逼近

Hannah Geiss, Stefan Geiss, Onni Hinkkanen

AI总结 研究在初始扩大滤子下用离散时间逼近某些随机积分的定量误差,发现逼近率与无额外信息时相同,但渐近常数更优。

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AI中文摘要

我们研究某些随机积分的定量逼近,其中我们在初始扩大滤子下使用离散时间逼近。结果表明,逼近率通常与无额外信息的情况相同,但渐近常数有所改善。

英文摘要

We study the quantitative approximation of certain stochastic integrals, where we use discrete time approximations under initial enlargement of filtration. It turns out that the approximation rate is in general the same as in the case of no additional information, however, the asymptotic constant improves.

2606.08774 2026-06-09 cs.IT math.IT 新提交

Non-Uniform Codebook Design for Optical IRS-Assisted VLC Systems

面向光学IRS辅助VLC系统的非均匀码本设计

Rashid Iqbal, Dimitrios Bozanis, Dimitrios Tyrovolas, Christos K. Liaskos, Muhammad Ali Imran, George K. Karagiannidis, Hanaa Abumarshoud

AI总结 针对光学智能反射面辅助室内可见光通信系统中均匀码本导致用户平面覆盖不均的问题,提出基于几何光学的非均匀码本设计,使反射波束更均匀分布,仿真验证了其优越性。

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AI中文摘要

光学智能反射面(OIRS)可以改善室内可见光通信(VLC)系统的覆盖范围,然而实际部署需要有限的离线码本,以避免对镜子方向进行重复的实时优化。具有固定角度步长的均匀码本无法在用户平面上提供均匀覆盖,因为从转向角度到用户平面上反射位置的映射是非线性的。为了解决这个问题,本文提出了一种基于几何光学的非均匀码本设计,用于OIRS辅助的VLC系统。所提出的方法根据每个IRS元素的几何位置为其构建单独的码本,使得反射波束在用户平面上分布更均匀。使用信道误差矩阵的Frobenius范数评估码本精度。仿真结果表明,与均匀码本相比,所提出的设计以更少的码字提供了更均匀的空间映射,并且扫描角度分辨率对码本精度的影响比倾斜角度分辨率更强。

英文摘要

Optical intelligent reflecting surfaces (OIRS) can improve the coverage of indoor visible light communication (VLC) systems, however, practical deployment requires a finite offline codebook to avoid repeated real-time optimisation of mirror orientations. A uniform codebook with fixed angular steps does not provide uniform coverage on the user plane, because the mapping from steering angles to reflection locations on the user plane is nonlinear. To address this problem, this paper proposes a geometric-optics-based non-uniform codebook design for OIRS-assisted VLC systems. The proposed method constructs an individual codebook for each IRS element according to its geometric position, so that the reflected beams are distributed more uniformly over the user plane. The codebook accuracy is evaluated using the Frobenius norm of the channel error matrix. Simulation results show that the proposed design provides more uniform spatial mapping with fewer codewords than the uniform codebook, and that the sweep-angle resolution has a stronger effect on the codebook accuracy than the tilt-angle resolution.

2606.08773 2026-06-09 astro-ph.SR astro-ph.HE 新提交

Mapping the Landscape of M Dwarf X-ray Flares: New Discoveries in Context

M矮星X射线耀斑的景观映射:新发现及其背景

Imri A. Dickstein, Maayane T. Soumagnac, Eran O. Ofek, Param Rekhi, Volker Perdelwitz, Sagi Ben-Ami, Thomas Kupfer

AI总结 通过交叉匹配eROSITA和钱德拉数据发现7颗M矮星的11次新X射线耀斑,结合文献样本分析M0-M6星的耀斑频率分布,并估算宜居行星大气完全流失的时间上限为0.5-30 Myr。

Comments Submitted to ApJ

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AI中文摘要

我们报告了通过将eROSITA对明亮、邻近M矮星的观测与钱德拉望远镜档案进行交叉匹配,发现了7颗此前未知存在耀斑活动的M矮星的11次X射线耀斑。为了在更广泛的背景下分析这些耀斑的特性,我们汇编了文献中已识别的15颗M矮星的所有已报告X射线耀斑样本。利用这个组合样本,我们推导出M0-M6星的X射线耀斑频率分布约束。我们测得的平均耀斑发生率为$\sim 10^{-1}\,\rm ks^{-1}$(相当于每天约9次耀斑)。该样本中的X射线耀斑能量范围从$10^{29}\,\rm erg$到$10^{33}\,\rm erg$,并显示出耀斑强度与持续时间之间的强相关性。我们表征的耀斑特性包括其持续时间、通量和温度增强以及时间不对称性。利用这些结果和最近关于耀斑驱动大气逃逸的模拟,我们推导出围绕这些M矮星运行的宜居类地行星完全失去其大气层所需的时间上限:0.5-30 Myr。

英文摘要

We report the discovery of 11 X-ray flares from 7 M dwarfs previously unknown to exhibit flaring activity, by cross-matching eROSITA observations of bright, nearby M dwarfs with the Chandra telescope archive. To analyze the properties of these flares in a broader context, we compile the sample of all reported X-ray flares from the 15 M dwarfs identified as flaring in the literature. We use this combined sample to derive constraints on the X-ray flare frequency distributions of M0-M6 stars. The average flare occurrence rate we measure is $\sim 10^{-1}\,\rm ks^{-1}$ (corresponding to $\sim 9$ flares per day). The X-ray flares in this sample span energies from $10^{29}\,\rm erg$ to $10^{33}\,\rm erg$ and exhibit a strong correlation between flare strength and duration. The flare properties we characterize include their durations, flux and temperature enhancements, and temporal asymmetries. Using these results and recent simulations of flare-driven atmospheric escape, we derive an upper limit on the time required for habitable Earth-like planets orbiting these M dwarfs to completely lose their atmospheres: 0.5-30 Myr.

2606.08772 2026-06-09 math.CO 新提交

Pairwise meets of antichains in $\mathbb{Z}^d$

$\mathbb{Z}^d$ 中反链的成对交

Guillermo Rey

AI总结 本文证明了 $\mathbb{Z}^d$ 中任意有限反链 $A$ 至少有 $c_d |A|^{d/(d-1)}$ 个不同的成对交,指数最优,并推导出下集等周不等式和整数最大公约数的下界。

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AI中文摘要

$\mathbb{Z}^d$ 中两个点的交是它们按坐标取最小值。我们证明 $\mathbb{Z}^d$ 中任意有限反链 $A$ 至少有 $c_d |A|^{d/(d-1)}$ 个不同的成对交,其中 $c_d > 0$ 仅依赖于 $d$,且指数 $d/(d-1)$ 是最优的。作为推论,我们得到下集的一个等周不等式:$\mathbb{Z}^d_{\geq 0}$ 中任意有限下集 $D$ 满足 $|D| \geq c_d |\max(D)|^{d/(d-1)}$,其中 $\max(D)$ 是其极大元集合。通过素因子分解,交的界也给出了最大公约数的下界:一个由至多 $d$ 个素数支撑的 $N$ 个整数的原始集合至少有 $c_d N^{d/(d-1)}$ 个不同的成对最大公约数。

英文摘要

The meet of two points in $\mathbb{Z}^d$ is their coordinatewise minimum. We show that every finite antichain $A$ in $\mathbb{Z}^d$ has at least $c_d |A|^{d/(d-1)}$ distinct pairwise meets, where $c_d > 0$ depends only on $d$, and that the exponent $d/(d-1)$ is best possible. As a corollary we obtain an isoperimetric inequality for downsets: every finite downset $D$ in $\mathbb{Z}^d_{\geq 0}$ satisfies $|D| \geq c_d |\max(D)|^{d/(d-1)}$, where $\max(D)$ is its set of maximal elements. By prime factorization the meet bound also yields a lower bound on greatest common divisors: a primitive set of $N$ integers supported on at most $d$ primes has at least $c_d N^{d/(d-1)}$ distinct pairwise gcds.

2606.08771 2026-06-09 quant-ph cs.IT math.IT 新提交

Algebra of Bivariate-Bicycle Surface Codes

双变量-自行车-曲面码的代数

Renyu Wang, Leonid P. Pryadko

AI总结 通过有限域上双变量多项式的公共根代数重数,确定双变量-自行车-曲面码的维数,并揭示倾斜边界结构,提出无需角修正的构造方法。

Comments 22 pages, 8 figures included

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AI中文摘要

我们将双变量-自行车-曲面(BBS)码的性质与它们在扩域中公共根的数量和位置联系起来,这些码由有限域上的一对双变量多项式构造。具有有限非零坐标的根$(x,y)$的数量(按代数重数计数)决定了码的维数。该维数在洛朗多项式环的单项式自同构下不变。相反,具有零或无穷大$x$或$y$坐标的根表明在相应边界附近需要专门的生成元(例如,对于$x$为零或无穷大的根,分别对应左边界或右边界)。这些根在单项式变换下可能出现或消失,这揭示了倾斜边界的结构。基于这些结果,我们制定了一个构造BBS码的方案,该方案适用于具有矩形、对角线和任意倾斜边界的区域。该方法的一个关键优势是,只要多项式满足特定方向的边缘条件,就无需角修正。

英文摘要

We relate the properties of bivariate-bicycle-surface (BBS) codes, constructed from a pair of bivariate polynomials over a finite field, to the number and location of their common roots in the extension field. The number of roots $(x,y)$ with finite, non-zero coordinates -- counted with algebraic multiplicity -- determines the dimension of the codes. This dimension is invariant under monomial automorphisms of the Laurent polynomial ring. Conversely, roots with zero or infinite $x$- or $y$-coordinates indicate that specialized generators are required near the corresponding boundary (e.g., the left or right boundary for a root where $x$ is zero or infinite, respectively). These roots can appear or disappear under monomial transformations, which reveals the structure of tilted boundaries. Based on these results, we formulate a prescription for constructing BBS codes that works for regions with rectangular, diagonal, and arbitrarily tilted boundaries. A key advantage of this approach is that no corner corrections are needed, provided the polynomials satisfy orientation-specific edge conditions.

2606.08767 2026-06-09 hep-th astro-ph.CO gr-qc 新提交

Fire at the Tip of the Throat: Hagedorn Phase after brane-antibrane inflation?

喉尖之火:膜-反膜暴胀后的哈格多恩相?

Dibya Chakraborty, Ahmed Rakin Kamal

AI总结 研究微扰模稳定膜-反膜暴胀后的开弦哈格多恩相,分析湮灭能量能否驱动可见区进入该相,并探讨对暗辐射的影响。

Comments 9 pages+ references

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AI中文摘要

我们在微扰模稳定的膜-反膜暴胀中研究了暴胀后的开弦哈格多恩相。在这类模型中,体积模量通过微扰修正而非超势的非微扰效应来稳定,从而避免了标准的膜-反膜$\eta$问题。由于暴胀通过快子凝聚和膜-反膜湮灭结束,终点本质上是弦论的,不必立即由普通辐射浴描述。我们分析了湮灭释放的能量能否将可见区驱动到开弦哈格多恩相,并研究了其对暗辐射的影响。如果标准模型膜位于与湮灭发生的同一喉中,我们发现,释放能量中沉积到幸存可见开弦中的一小部分就足以进入哈格多恩区域,并可以将相对论性物种的有效数量$\Delta N_{\rm eff}$压低到当前观测界限以下。如果标准模型位于不同的喉中,结果取决于喉间能量转移:即时或延迟转移仍可能产生可见的哈格多恩相。然而,当标准模型喉中的局部弦尺度低于或接近于湮灭喉中的弦尺度时,该机制最为有效。

英文摘要

We study the post-inflationary open-string Hagedorn phase in perturbatively moduli stabilized brane-antibrane inflation. In this class of models, the volume modulus is stabilized by perturbative corrections rather than by non-perturbative effects to the superpotential, thereby avoiding the standard brane-antibrane $η$-problem. Since inflation ends through tachyon condensation and brane-antibrane annihilation, the endpoint is intrinsically stringy and need not be described immediately by an ordinary radiation bath. We analyze whether the energy released at annihilation can drive the visible sector into an open-string Hagedorn phase, and study the consequences for dark radiation. If the Standard Model (SM) branes lie in the same throat as where the annihilation occurs, we find that a modest fraction of the released energy deposited into surviving visible open strings is sufficient to enter the Hagedorn regime and can suppress the effective number of relativistic species $ΔN_{\rm eff}$ below current observational bounds. If the SM lies in a different throat, the result depends on inter-throat energy transfer: prompt or delayed transfer can still yield a visible Hagedorn phase. However, the mechanism is most efficient when the local string scale in the SM throat is lower than or comparable to that in the annihilation throat.

2606.08764 2026-06-09 gr-qc 新提交

Non-Perturbative Bounds on Cosmological Backreaction, the Non-Linear Scale, and Gauge-Invariant Mutual Information from the Matter Power Spectrum

宇宙学反作用的非微扰界限、非线性尺度以及来自物质功率谱的规范不变互信息

Bob Osano

AI总结 利用介观粗粒化框架,推导了宇宙学反作用的非微扰下界,将累积量展开收敛半径与物质功率谱非线性尺度关联,并证明高斯场中互信息的规范不变性。

Comments 8 pages

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AI中文摘要

我们将~\cite{OsanoMeso,OsanoExtensivity,OsanoPerturbation}的介观粗粒化框架应用于宇宙学微扰理论和反作用争论中的三个问题。\textbf{(i)}~基于Gibbs--Bogoliubov不等式,推导了Buchert方程中运动学反作用$\QD$的非微扰下界:只要系统满足稳定性和温和性,无论非线性程度如何,$\QD$不能被抑制到其线性微扰理论值以下。\textbf{(ii)}~介观累积量展开的收敛半径等于$O(\kNL^{-1})$,即物质功率谱的非线性尺度,这为为什么标准微扰理论在$k>\kNL$时失效提供了KAM定理解释。\textbf{(iii)}~对于高斯物质场,单元间的互信息恰好为$I(i,j)=-\tfrac{1}{2}\ln(1-r_{ij}^2)$,在线性阶是规范不变的,可直接从观测的$P(k)$计算;对于$\ell=50\,\mathrm{Mpc}\,h^{-1}$的$Λ$CDM模型,$I_{\rm NN}\approx 0.10$。总互信息提供了对FRW自由能反作用修正的可数据计算度量。规范证明在线性阶成立;KAM识别是精确的;反作用下界基于一个陈述的猜想。

英文摘要

We apply the mesoscopic coarse-graining framework of~\cite{OsanoMeso,OsanoExtensivity,OsanoPerturbation} to three problems in Cosmological Perturbation Theory and the backreaction debate. \textbf{(i)}~A non-perturbative lower bound on the kinematic backreaction $\QD$ in the Buchert equations, derived from the Gibbs--Bogoliubov inequality: $\QD$ cannot be suppressed below its linear-perturbation-theoryvalue, regardless of the degree of non-linearity, provided the system satisfies stability and temperedness. \textbf{(ii)}~The radius of convergence of the mesoscopic cumulant expansion equals $O(\kNL^{-1})$, the non-linear scale of the matter power spectrum, providing a KAM-theorem explanation for why standard perturbation theory fails at $k>\kNL$. \textbf{(iii)}~For a Gaussian matter field, the inter-cell mutual information is exactly $I(i,j)=-\tfrac{1}{2}\ln(1-r_{ij}^2)$, gauge-invariant at linear order and computable directly from the observed $P(k)$; for $Λ$CDM at $\ell=50\,\mathrm{Mpc}\,h^{-1}$, $I_{\rm NN}\approx 0.10$.The total mutual information gives a data-computable measure of the backreaction correction to the FRW free energy. The gauge proof holds at linear order; the KAM identification is exact; the backreaction bound rests on a stated conjecture.

2606.08763 2026-06-09 cond-mat.soft 新提交

Energy Barriers for Reversible Chain Scission and Healing under Tension with Displacement Control

位移控制下可逆链断裂与愈合的能垒

Mohammad A. Ansari, Kenneth M. Liechti, Dmitrii E. Makarov, Rui Huang

AI总结 提出可断裂自由连接链模型,揭示位移控制下聚合物链可逆断裂与愈合的能垒机制,预测速率依赖的断裂力存在上下界。

Comments Under review

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AI中文摘要

聚合物链断裂是软材料断裂的关键机制。单分子力谱实验已知,链断裂的临界条件取决于加载速率和其他环境效应(如温度和溶剂)。描述链断裂动力学的常用方法通常假设力控制条件,即聚合物链由预定力拉伸。由于这一假设,链断裂是不可逆的,排除了愈合的可能性。然而,在许多软材料中,断裂后观察到自愈合,表明可能存在可逆的链断裂。这里,我们证明在位移控制条件下,即聚合物链以预设的端到端距离拉伸时,可逆链断裂是可能的。我们提出了一个可断裂的自由连接链模型,假设当聚合物链的一个键断裂而其他键保持近乎刚性时,链断裂。在预设的端到端距离下,链的自由能有两个局部极小值和一个局部极大值(过渡态),从而产生链断裂和愈合的能垒。随着预设位移的增加,断裂的能垒降低而愈合的能垒升高,这取决于链长(键数)和键的势能。利用这些能垒,我们采用动力学方法预测单根聚合物链在拉伸下的统计和动力学行为,首先通过积分速率方程,然后通过动力学蒙特卡洛模拟。值得注意的是,本模型预测了速率依赖的链断裂,断裂力的下界可能比上界(接近共价键的理论强度)低几个数量级。

英文摘要

Polymer chain scission is a key mechanism for fracture of soft materials. It is well known from single-molecule force spectroscopy experiments that the critical condition for chain scission depends on the loading rate and other environmental effects (e.g., temperature and solvent). Common approaches to describing the kinetics of chain scission often assume force-controlled conditions, that is, when a polymer chain is stretched by a prescribed force. As a result of this assumption, chain scission is irreversible, excluding the possibility of healing. In many soft materials, however, self-healing has been observed after fracture, suggesting possibly reversible chain scission. Here, we show that reversible chain scission is possible under displacement-controlled conditions, that is, when a polymer chain is stretched with a prescribed end-to-end distance. We present a breakable freely-jointed chain model, assuming that a polymer chain breaks when one of its links breaks while the other links remain nearly rigid. At a prescribed end-to-end distance, the free energy of the chain has two local minima and a local maximum (the transition state), giving rise to energy barriers for chain scission and healing. As the prescribed displacement increases, the energy barrier decreases for scission but increases for healing, depending on the chain length (number of links) and the potential energy of the link. With the energy barriers, we adopt a kinetic approach to predict the statistics and kinetics of a single polymer chain under tension, first by integrating the rate equation and then by kinetic Monte Carlo simulations. Notably, the present model predicts rate-dependent chain scission, with a lower bound for the rupture force that could be several orders of magnitude lower than the upper bound (which is close to the theoretical strength of the covalent bonds).

2606.08762 2026-06-09 math.CO 新提交

Many holes but no large one: maximizing $k$-holes while forbidding $(k+1)$-holes

多孔但无大孔:在禁止$(k+1)$-孔的情况下最大化$k$-孔

Martin Andričík, Alica Dományová, Adam Džavoronok, Aleksa Džuklevski, Matouš Šafránek

AI总结 研究平面一般位置点集不含空凸$(k+1)$-边形时最多空凸$k$-边形个数$m_{k,k+1,n}$,确定小过剩情形精确值$m_{k,k+1,k+a}=2^a$,并给出比例情形和固定$k$情形的上下界。

Comments 18 pages, 7 figures

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AI中文摘要

我们研究平面一般位置$n$点集不含空凸$\ell$-边形时最多空凸$k$-边形($k$-孔)个数$m_{k,\ell,n}$,聚焦于第一个非平凡情形$\ell=k+1$。我们的主要结果确定了小过剩情形的精确值:对于$n=k+a$且$a\le k/2-1$,我们证明$m_{k,k+1,k+a}=2^a$。我们还描述了达到等式的极值构型。超出此精确范围,我们在比例情形$n=\alpha k$以及$k$固定且$n$趋于无穷的情形中给出了上下界。在最后提及的情形中,我们证明$m_{k,k+1,n}=\Omega_k(n^{\lfloor\frac{k}{3}\rfloor})$和$m_{k,k+1,n}=O_k(n^{\lceil\frac{k}{2}\rceil+1})$。

英文摘要

We study the maximal number $m_{k,\ell,n}$ of empty convex $k$-gons ($k$-holes) determined by an $n$-point set in the plane in general position that contains no empty convex $\ell~$-gon, focusing on the first nontrivial case $\ell=k+1$. Our main result determines the exact value in the small-excess regime: for $n=k+a$ with $a\le k/2-1$, we prove $m_{k,k+1,k+a}=2^a.$ We also describe the extremal configurations attaining equality. Beyond this exact range, we provide upper and lower bounds in the proportional regime $n=αk$ and in the regime where $k$ is fixed and $n$ goes to infinity. In the last mentioned regime we prove that $m_{k,k+1,n}=Ω_k(n^{\lfloor\frac{k}{3}\rfloor})$ and $m_{k,k+1,n}=O_k(n^{\lceil\frac{k}{2}\rceil+1}).$

2606.08760 2026-06-09 quant-ph physics.comp-ph 新提交

Visual-to-Code Authoring, Tensor-Network Debugging, and Quantum-Circuit Inspection Tools in Python

Python中的可视化到代码创作、张量网络调试和量子电路检查工具

Alejandro Mata Ali

AI总结 提出三个互补包:张量网络可视化、张量网络编辑器和量子电路绘制器,分别用于视觉调试、可视化到代码创作和电路检查,以增强张量网络和量子电路的结构可见性和可编辑性。

Comments 15 pages, 6 figures, 6 tables

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AI中文摘要

张量网络和量子电路是结构对象,其含义取决于连接性、索引、收缩顺序、门放置、测量和相关设计选择。它们通常比代码更容易通过视觉进行推理,但在Python中,它们通常通过后端特定对象或紧凑符号表达式进行构建、转换和检查。这可能会使结构错误在开发、调试和通信过程中难以察觉。本文提出了三个互补包:Tensor-Network-Visualization,用于支持张量网络和跟踪einsum工作流的视觉调试和结构检查;Tensor-Network-Editor,用于可视化到代码创作、后端代码生成、JSON保存、导出和设计级分析;以及Quantum Circuit Drawer,用于清晰的电路渲染、检查以及电路或文档化结果分布的补充比较。这些包在现有张量网络库、基于数组的科学Python工作流和量子SDK之上形成了一个视觉创作和检查层。它们不是模拟器:它们不实现新的收缩算法,不执行量子电路,也不保证任意后端之间的完全语义等价。它们的贡献是使结构工件在这些生态系统中可见、可编辑、可检查、可比较、可导出和可重现。

英文摘要

Tensor networks and quantum circuits are structural objects whose meaning depends on connectivity, indices, contraction order, gate placement, measurements, and related design choices. They are often easier to reason about visually than as code, yet in Python they are frequently constructed, transformed, and checked through backend-specific objects or compact symbolic expressions. This can make structural mistakes hard to notice during development, debugging, and communication. This paper presents three complementary packages: Tensor-Network-Visualization for visual debugging and structural inspection of supported tensor-network and traced einsum workflows; Tensor-Network-Editor for visual-to-code authoring, backend code generation, JSON preservation, export, and design-level analysis; and Quantum Circuit Drawer for clear circuit rendering, inspection, and complementary comparison of circuits or documented result distributions. The packages form a visual authoring and inspection layer around existing tensor-network libraries, array-based scientific Python workflows, and quantum SDKs. They are not simulators: they do not implement new contraction algorithms, execute quantum circuits, or guarantee full semantic equivalence across arbitrary backends. Their contribution is to make structural artifacts visible, editable, inspectable, comparable, exportable, and reproducible within those ecosystems.

2606.08759 2026-06-09 physics.plasm-ph 新提交

Direct experimental measurement of ion properties in extreme plasma condition

极端等离子体条件下离子性质的直接实验测量

Evan M. Aguirre, Surabhi Jaiswal, Sergey Khrapak, Parth Mehrotra

AI总结 利用激光诱导荧光在电容耦合等离子体放电中直接测量离子性质,发现离子定向运动速度远超热运动,且离子温度高于室温,为等离子体加工和尘埃等离子体研究提供了关键数据。

Comments 10 pages, 4 figures

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AI中文摘要

我们演示了在电容耦合等离子体(CCP)放电中利用激光诱导荧光(LIF)直接测量最关键的离子性质,该放电模式适用于与等离子体加工和尘埃等离子体研究相关的广泛等离子体研究,这些研究多年来一直无法实现。在存在和不存在尘埃颗粒的情况下的离子流测量表明,离子的定向运动速度远快于热运动预期,并且在存在尘埃颗粒时观察到速度降低。还发现离子温度超过室温,这与尘埃等离子体领域的常见假设相反。这些发现代表了实验等离子体研究的重大进展,为改进离子驱动过程模型提供了关键信息,其见解跨越多个研究领域。

英文摘要

We have demonstrated Laser Induced Fluorescence (LIF) in a Capacitively Coupled Plasma (CCP) discharge to directly measure the most crucial ion properties at a discharge regime suitable for a broad range of plasma research related to plasma processing and dusty plasma investigations that has been impossible for many years. The ion flow measurements in the presence and absence of dust particles show that ions move much faster directionally than expected from thermal motion, with reductions observed in the presence of dust particles. Ion temperatures are also found to exceed room temperature, contrary to a common assumption in the dusty plasma community. These findings represent a significant advancement in experimental plasma research, providing vital information to refine ion-driven process models with insights that span multiple research fields.

2606.08758 2026-06-09 quant-ph 新提交

Neural network decoder confidence as a learned proxy for the logical gap

神经网络解码器置信度作为逻辑间隙的学习代理

David Dentelski

AI总结 研究利用图神经网络解码器的logit作为逻辑间隙的代理,通过后选择降低逻辑错误率,并发现其置信度更接近理想值。

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AI中文摘要

为了利用量子纠错码,解码器必须从测量的综合征中推断逻辑扇区。除了产生硬逻辑决策外,一些解码器还提供估计该决策可靠性的软信息。对于最小权重完美匹配(MWPM),一种常见的置信度度量是互补间隙或逻辑间隙。这里我们测试图神经网络(GNN)解码器的logit是否可以作为逻辑间隙的学习代理。使用在均匀电路级噪声下旋转表面码的预训练GNN [Physical Review Research, 7(2):023181, 2025],我们在相同采样的综合征上将其软输出与MWPM互补间隙进行比较。我们发现基于GNN logit的后选择产生的逻辑错误率低于基于MWPM间隙的后选择。逐次来看,有符号的GNN置信度分布在低和中间值处类似于有符号的MWPM间隙,但对许多正确解码的shots赋予更高的置信度。虽然两个分数都近似于后验对数似然比,但GNN置信度幅度更接近其理想值。这些结果表明,仅基于综合征和逻辑标签训练的神经网络解码器同时学习了类似间隙的判别能力和定量置信度尺度,从而在MWPM间隙估计不可用、成本高或与噪声模型不匹配时,能够实现基于置信度的后选择。

英文摘要

To utilize quantum error-correcting codes, a decoder must infer the logical sector from the measured syndrome. Beyond producing a hard logical decision, some decoders provide soft information that estimates the reliability of that decision. For minimum-weight perfect matching (MWPM), a common confidence measure is the complementary, or logical, gap. Here we test whether the logit of a graph neural network (GNN) decoder can act as a learned proxy for the logical gap. Using a pretrained GNN for the rotated surface code under uniform circuit-level noise [Physical Review Research, 7(2):023181, 2025], we compare its soft output with the MWPM complementary gap on the same sampled syndromes. We find that post-selection based on the GNN logit yields a lower logical error rate than one based on the MWPM gap. Shot-by-shot, the signed GNN confidence distribution resembles the signed MWPM gap at low and intermediate values, but assigns higher confidence to many correctly decoded shots. While both scores approximate the posterior log-likelihood ratio, the GNN confidence magnitude is closer to its ideal value. These results show that a neural-network decoder trained only on syndromes and logical labels learns both gap-like discrimination and a quantitative confidence scale, enabling confidence-based post-selection when MWPM gap estimates are unavailable, costly, or poorly matched to the noise model.

2606.08757 2026-06-09 cond-mat.mtrl-sci cond-mat.mes-hall 新提交

Chiral-Angle-Controlled Altermagnetic Spin Splitting in Nanotubes

纳米管中手性角控制的交变磁自旋劈裂

Ersoy Sasioglu, Tom. G. Saunderson, Börge Göbel, Ingrid Mertig, Samir Lounis

AI总结 通过将二维d波交变磁体卷成纳米管,利用维度投影将动量依赖的自旋劈裂转化为手性角控制的一维自旋劈裂,并展示其cos(2θ)依赖关系。

Comments 5 pages, 3 figures

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AI中文摘要

交变磁体表现出动量依赖的自旋劈裂,尽管净磁化强度为零。在这里,我们展示了将二维(2D)$d$波交变磁体卷成纳米管,通过维度投影将这种动量依赖的自旋劈裂转化为手性角控制的一维(1D)自旋劈裂。使用最小紧束缚模型和第一性原理计算,我们证明了纳米管自旋劈裂遵循特征性的$\cos(2θ)$依赖关系,在节点取向消失,在反节点取向达到极值。该机制在源自二维交变磁体的广泛纳米管类别中保持稳健。我们的结果确立了维度投影作为将动量依赖的交变磁自旋劈裂转移到一维系统的通用途径,并为在低维磁性材料中工程化自旋劈裂量子态提供了框架。

英文摘要

Altermagnets exhibit momentum-dependent spin splitting despite having zero net magnetization. Here, we show that rolling a two-dimensional (2D) $d$-wave altermagnet into a nanotube transforms this momentum-dependent spin splitting into chiral-angle-controlled one-dimensional (1D) spin splitting through dimensional projection. Using a minimal tight-binding model and first-principles calculations, we demonstrate that the nanotube spin splitting follows a characteristic $\cos(2θ)$ dependence, vanishing for nodal orientations and reaching extrema for antinodal orientations. The mechanism remains robust across a broad class of nanotubes derived from 2D altermagnets. Our results establish dimensional projection as a general route for transferring momentum-dependent altermagnetic spin splitting into 1D systems and provide a framework for engineering spin-split quantum states in low-dimensional magnetic materials.

2606.08756 2026-06-09 quant-ph cond-mat.dis-nn cond-mat.stat-mech 新提交

Quantum resource localizability transitions in deep thermalization

深度热化中的量子资源局域化转变

Xiaozhou Feng, Chang Liu, Zihan Cheng, Wen Wei Ho, Matteo Ippoliti

AI总结 研究量子资源约束如何影响深度热化,发现资源理论分为平滑局域化和阈值局域化两类,后者导致局域资源从无到有的尖锐转变,并揭示了零率量子纠错码中的新魔法转变。

Comments 29+6 pages,10 figures

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AI中文摘要

我们研究量子资源约束如何影响深度热化,即从量子多体态的部分测量中涌现的通用局部波函数分布。量子资源,如非稳定子性(魔法)、相干性、不对称性、虚数性和非高斯性,对于量子信息处理至关重要,对其全局丰度的约束可以重塑这些涌现分布。为了解决这个问题,我们在一般量子资源理论(QRTs)中开发了一个深度热化的统一框架。我们的核心结果是,QRTs分为两类:“平滑局域化”(SL)QRTs,其中局部后测量状态的资源含量随全局资源密度(由初始状态和测量基设定)连续变化,产生连续可调的波函数分布;以及“阈值局域化”(TL)QRTs,其中局部资源含量在超过临界全局资源阈值时从不连续地跳到接近最大,产生从无资源、“深度遍历性破缺”分布到资源丰富、最大随机分布的尖锐转变。我们将这种SL-TL二分法追溯到一个信息论机制——块锐化:通过将每个QRT视为希尔伯特空间中块之间的相干性,我们表明局部资源含量取决于测量将初始叠加态坍缩到单个无资源块的能力。我们的理论是可解析处理的,并定量预测了所有研究的QRTs中的相边界,我们通过大量数值模拟验证了这一点。最后,我们强调了两个后果:零率量子纠错码中的新型魔法转变——以前被认为只发生在有限速率下——以及基于后测量状态集合的量子资源认证协议的新含义。

英文摘要

We investigate how quantum resource constraints affect deep thermalization, the emergence of universal local wavefunction distributions from partial measurements of a quantum many-body state. Quantum resources, such as non-stabilizerness (magic), coherence, asymmetry, imaginarity, and non-Gaussianity, are essential for quantum information processing, and constraints on their global abundance can reshape these emergent distributions. To address this question, we develop a unified framework for deep thermalization within general quantum resource theories (QRTs). Our central result is that QRTs fall into two classes: ``smoothly localizable'' (SL) QRTs, where the resource content of local post-measurement states changes continuously with the global resource density, set by the initial state and measurement basis, yielding continuously tunable wavefunction distributions; and ``threshold localizable'' (TL) QRTs, where the local resource content jumps discontinuously from minimal to near-maximal past a critical global resource threshold, producing a sharp transition between a resourceless, ``deep-ergodicity breaking'' distribution and a resourceful, maximally random one. We trace this SL-TL dichotomy to an information-theoretic mechanism, block sharpening: by viewing each QRT as coherence between blocks in Hilbert space, we show that the local resource content depends on the measurement's ability to collapse an initial superposition into a single resourceless block. Our theory is analytically tractable and quantitatively predicts the phase boundaries across all studied QRTs, which we validate with extensive numerical simulations. Finally, we highlight two consequences: a novel magic transition in zero-rate quantum error-correcting codes--previously believed to occur only at finite rates--and new implications for quantum resource certification protocols based on post-measurement state ensembles.

2606.08754 2026-06-09 math.DS math.CV 新提交

On the support of measures of large entropy for Hénon-Sibony maps

关于Hénon-Sibony映射大熵测度的支撑集

Sobir Boymurodov

AI总结 研究Hénon-Sibony映射的大熵不变测度的支撑集,证明若测度熵大于某阈值则支撑在Julia集上。

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AI中文摘要

设$f$是$\mathbb{C}^k$上的Hénon-Sibony映射,代数次数$d_+\geq 2$,其逆$f^{-1}$的代数次数为$d_-$。$f$的拓扑熵等于$\log d_+^{p} = \log d_-^{k-p}$。我们证明,每个满足$h_ν(f)>\log \max\{ d_+^{p-1},d_-^{k-p-1}\}$的遍历$f$-不变测度$ν$的支撑集包含在$f$的Julia集$\mathcal{J}$中。

英文摘要

Let $f$ be a Hénon-Sibony map of $\mathbb{C}^k$ of algebraic degree $d_+\geq 2$, whose inverse $f^{-1}$ has algebraic degree $d_-$. The topological entropy of $f$ is equal to $\log d_+^{p} = \log d_-^{k-p}$. We show that every ergodic $f$-invariant measure $ν$ satisfying $h_ν(f)>\log \max\{ d_+^{p-1},d_-^{k-p-1}\}$ is supported on the Julia set $\mathcal{J}$ of $f$.

2606.08753 2026-06-09 math-ph math.MP 新提交

Tight-Binding Spectra of Finite Incidence Geometries: From Spatial Localization to $SU(6)$ Flavor Symmetry

有限关联几何的紧束缚谱:从空间局域化到$SU(6)$味对称性

Pawel Nurowski

AI总结 研究有限几何构型二分Levi图上的紧束缚谱,通过实平面嵌入导致空间局域化,复射影平面恢复布洛赫波;解析推导Schläfli双六和Cremona-Richmond构型的谱分解,发现几何受挫驱动的宏观零能平带;建立与标准模型SU(6)味对称性的结构同构,平带对应超重重子冻结。

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AI中文摘要

我们研究了定义在有限几何构型的二分Levi图上的紧束缚量子哈密顿量的谱性质。在第一部分中,我们分析了$10_3$ Desargues和Kantor构型,展示了由实平面嵌入($\mathbb{R}\mathbb{P}^2$)引起的确定性空间形变如何破坏平移对称性,导致结构波局域化。我们展示了在复射影平面($\mathbb{C}\mathbb{P}^2$)中的嵌入如何通过合成规范相位恢复布洛赫波传播。在第二部分中,我们评估了$\mathbb{R}^3$中的Schläfli双六($12_5, 30_2$)和Cremona-Richmond($15_3$)构型。我们解析推导了它们的精确谱分解,确认了完全由几何受挫驱动的宏观零能平带($E=0$)的存在。在第三部分中,我们建立了这些离散紧束缚网络与标准模型味对称性扇区之间的形式结构同构。我们将Schläfli图映射到$SU(6)$味多重态,其中平带对应于超重重子的运动学冻结。最后,我们讨论了互补的Cremona-Richmond $15_3$拓扑,展示了其独特的几何性质(基于三切平面而非点交点)如何为27条线的$W(E_6)$对称性提供纯代数的拓扑完备化。

英文摘要

We investigate the spectral properties of tight-binding quantum Hamiltonians defined on the bipartite Levi graphs of finite geometric configurations. In Part I, we analyze the $10_3$ Desargues and Kantor configurations, demonstrating how deterministic spatial deformations induced by real planar embeddings ($\mathbb{R}\mathbb{P}^2$) destroy translational symmetry, leading to structural wave localization. We show how embedding in the complex projective plane ($\mathbb{C}\mathbb{P}^2$) restores Bloch wave propagation via synthetic gauge phases. In Part II, we evaluate the Schläfli double six ($12_5, 30_2$) and the Cremona-Richmond ($15_3$) configurations in $\mathbb{R}^3$. We analytically derive their exact spectral decompositions, confirming the existence of macroscopic zero-energy flat bands ($E=0$) driven entirely by geometric frustration. In Part III, we establish a formal structural isomorphism between these discrete tight-binding networks and the flavor symmetry sector of the Standard Model. We map the Schläfli graph to the $SU(6)$ flavor multiplets, where the flat band corresponds to the kinematic freezing of ultra-heavy baryons. Finally, we discuss the complementary Cremona-Richmond $15_3$ topology, demonstrating how its distinct geometric nature (based on tritangent planes rather than point intersections) provides a purely algebraic, topological completion to the $W(E_6)$ symmetry of the 27 lines.

2606.08752 2026-06-09 astro-ph.HE 新提交

On The Nature of Einstein Probe Transient EP250916a: Insights from X-ray, Optical, and Radio Observations

爱因斯坦探针瞬变源EP250916a的性质:来自X射线、光学和射电观测的见解

Gaurava K. Jaisawal, Giulia Illiano, Francesco Carotenuto, Astrid L. Bouquin, David M. Russell, Giorgos Leloudas, Andrea Sanna, Dalya Akl, Rob Fender, Sara Motta

AI总结 通过多波段观测,研究EP250916a的X射线快速增亮、硬谱、弱准周期振荡及无射电对应体等特征,支持其作为低光度硬态黑洞X射线双星候选体。

Comments Accepted for publication in The Astrophysical Journal, 16 pages, 7 figures

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AI中文摘要

我们报告了瞬变源EP250916a的多波段研究,该源由爱因斯坦探针于2025年9月16日探测到。位于低银纬,该源表现出快速的X射线增亮,达到未吸收的0.5--10 keV流量$(6.4 \pm 0.1) \times 10^{-10}$ erg cm$^{-2}$ s$^{-1}$,随后是一个平台和持续超过40天的两阶段衰减。Swift/XRT监测显示持续硬谱($Γ\approx 1.6$--2.2),衰减期间仅轻微软化,而NuSTAR观测确认了延伸至70 keV的硬态连续谱。XMM-Newton数据的时变分析揭示了一个约13 Hz的弱准周期振荡(QPO)。未探测到其他相干脉动或热核爆发。宽带谱建模倾向于具有部分覆盖吸收的非热幂律连续谱,且未显示显著的热盘成分。使用NOT/ALFOSC、LCO和GaiaDR3获得的光学成像在2角秒Swift/XRT位置不确定度内识别出两个暗弱源。MeerKAT在1.28 GHz的观测未发现射电对应体,3σ上限为60 $μ$Jy beam$^{-1}$。长时间爆发、硬非热X射线谱、弱QPO探测、缺乏相干时变特征以及暗弱潜在光学对应体的组合,不支持恒星耀发或河外起源,而支持吸积致密天体场景。与类似暗弱硬态瞬变源的比较将EP250916a置于一个不断增长的低光度硬态黑洞X射线双星候选体群体中。

英文摘要

We report multi-wavelength studies of the transient EP250916a, detected by the Einstein Probe on 2025 September 16. Located at low Galactic latitude, the source exhibited a rapid X-ray brightening, reaching an unabsorbed 0.5--10 keV flux of $(6.4 \pm 0.1) \times 10^{-10}$ erg cm$^{-2}$ s$^{-1}$, followed by a plateau and a two-stage decay lasting over 40 days. Swift/XRT monitoring shows a persistently hard spectrum ($Γ\approx 1.6$--2.2) with only modest softening during decay, while a NuSTAR observation confirms a hard-state continuum extending up to 70 keV. Timing analysis of XMM-Newton data reveals a weak quasi-periodic oscillation (QPO) at $\sim$13 Hz. No other coherent pulsations or thermonuclear bursts are detected. Broadband spectral modeling favors a nonthermal power-law continuum with partial-covering absorption, and shows no significant thermal disk component. Optical imaging obtained with NOT/ALFOSC, LCO, and GaiaDR3 identifies two faint sources within the 2 arcsec Swift/XRT positional uncertainty. A MeerKAT observation at 1.28 GHz yielded no radio counterpart, with a 3$σ$ upper limit of 60 $μ$Jy beam$^{-1}$. The combination of a long-lasting outburst, a hard nonthermal X-ray spectrum, a weak QPO detection, the absence of coherent timing features, and faint potential optical counterparts disfavors a stellar-flare or extragalactic origin and supports an accreting compact-object scenario. Comparisons with similar faint, hard-state transients place EP250916a within a growing population of low-luminosity, hard-state black hole X-ray binary candidates.

2606.08750 2026-06-09 cs.IT math.CO math.IT 新提交

New Codes from Cyclic and Negacyclic Codes of Even Length over $\mathbb{Z}_4$

来自 $\mathbb{Z}_4$ 上偶数长循环码和负循环码的新码

Nuh Aydin, Mohamed O. Belghith, Godwin Idowu, Trang T. T. Nguyen, Long B. Tran

AI总结 利用已有理论结果设计搜索算法,从偶数长循环码和负循环码中找到2500个新循环码和730个负循环码,并导出参数良好的二元量子码。

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AI中文摘要

本文利用文献中先前建立的理论结果,设计搜索算法,从 $\mathbb{Z}_4$ 上偶数长的循环码和负循环码中寻找新的线性码。通过这些搜索,我们找到了2500个新的循环码和730个负循环码。与先前已知的码相比,这些新码展现出改进的参数。此外,我们从这些 $\mathbb{Z}_4$ 码中获得了具有良好参数的二元量子码。

英文摘要

This paper uses theoretical results previously established in the literature to design search algorithms to find new linear codes over $\mathbb{Z}_4$ from cyclic and negacyclic codes of even length. As a result of these searches, we have found 2500 new cyclic codes and 730 negacyclic codes. These new codes exhibit improved parameters compared to previously known codes. Additionally, we have obtained binary quantum codes with good parameters from such $\mathbb{Z}_4$ codes.

2606.08749 2026-06-09 eess.IV 新提交

Active Source-free Domain Adaptation in Open-set Medical Image Segmentation via Decomposed Uncertainty and Prototype Discrepancy

基于分解不确定性和原型差异的开放集医学图像分割中的主动源自由域适应

Jin Yang, Yichi Zhang, Peijie Qiu, Xiaobing Yu

AI总结 提出一种主动源自由开放集域适应方法,通过类感知分解不确定性和类无关原型差异选择目标样本,结合目标精炼自训练策略,实现无源数据下的开放集医学图像分割。

Comments Early accepted by MICCAI 2026. This version is not the Version of Record and does not reflect post-acceptance improvements, or any corrections

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AI中文摘要

深度学习方法由于域偏移,在不同分割数据集上难以展现稳健性能,但主动域适应技术通过从目标域查询少量样本进行适应训练,增强了其泛化性能。然而在临床实践中,目标域通常包含源数据中未出现的新解剖结构或病理的私有类别,现有方法实现的是源域和目标域具有相同分割类别的封闭集分割。此外,由于严格的数据隐私规定,适应过程中通常无法访问源数据。为解决这些限制,我们提出了一种主动源自由开放集域适应(ASFOSDA)方法,这是首个在无源数据访问情况下,将主动学习用于开放集医学图像分割中深度学习模型适应的工作。该方法采用主动开放集查询策略,基于类感知分解不确定性(CDU)和类无关原型差异(CPD)选择最具信息量的目标样本来训练模型。CDU通过在随机过程中使用测试时增强,测量样本的偶然不确定性和模型的认知不确定性。CPD测量跨域和自域差异,以选择多样化的样本。随后,为通过增强训练样本来提升适应性能,提出了一种目标精炼自训练策略,为未选择样本生成高质量伪标签,从而将其与标记样本结合进行半监督训练。我们在跨域开放集体积医学图像分割任务上评估了该方法,它优于最先进的适应方法。

英文摘要

Deep learning (DL) methods are challenged to demonstrate robust performance across different segmentation datasets due to domain shifts, but active domain adaptation techniques enhance their generalization performance by querying a few samples from target domains for adaptation training. However in clinical practice, target domains often include private classes of new anatomical structures or pathologies that are not presented in the source data, and existing methods implement closed-set segmentation where source and target domains have the same segmentation classes. Additionally, source data are often inaccessible during adaptation due to strict data privacy regulations. To address these limitations, we propose an Active Source-free Open-set Domain Adaptation (ASFOSDA) method which is the first work to implement active learning for adapting DL models in open-set medical image segmentation without the access to source data. This method employs an active open-set query strategy to select the most informative target samples for training models based on Class-aware Decomposed Uncertainty (CDU) and Class-agnostic Prototype Discrepancy (CPD). CDU measures sample aleatoric uncertainty and model epistemic uncertainty by employing test time augmentation in stochastic processes. CPD measures cross-domain and self-domain discrepancy for selecting diverse samples. Subsequently, to boost the adaptation performance by enhancing training samples, a Target-refined Self-training strategy is proposed to generate high-quality pseudo labels for unselected samples, thus combining them with labeled samples for a semi-supervised training. We evaluated our method on cross-domain open-set volumetric medical image segmentation tasks, and it outperformed state-of-the-art adaptation methods.