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2505.09130 2026-06-03 math.AG

Quartic curves in the quintic del Pezzo threefold

五次 del Pezzo 三维簇上的四次曲线

Kiryong Chung, Jaehyun Kim, Jeong-Seop Kim

AI总结 本文证明五次 del Pezzo 三维簇 X5 上有理四次曲线的 Hilbert 概形 H4(X5) 同构于 X5 上直线的 Hilbert 概形上的 Grassmannian 丛,因此光滑且不可约。

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AI中文摘要

在本文中,我们证明了五次 del Pezzo 三维簇 X5 上有理四次曲线的 Hilbert 概形 H4(X5) 同构于 X5 上直线的 Hilbert 概形上的 Grassmannian 丛。特别地,H4(X5) 是光滑且不可约的。我们的方法基于 Fanelli-Gruson-Perrin 在关于 X5 的稳定映射模空间的工作中研究的 X5 上有理四次曲线的几何性质。

英文摘要

In this paper, we prove that the Hilbert scheme $\mathbf{H}_4(X_5)$ of rational quartic curves on the quintic del Pezzo threefold $X_5$ is isomorphic to a Grassmannian bundle over the Hilbert scheme of lines on $X_5$. In particular, $\mathbf{H}_4(X_5)$ is smooth and irreducible. Our approach builds upon the geometry of rational quartic curves on $X_5$ studied by Fanelli-Gruson-Perrin in their work on the moduli space of stable maps to $X_5$.

2505.06338 2026-06-03 hep-th astro-ph.HE hep-ph

Towards holographic color superconductivity in QCD

全息QCD中的色超导研究

Jesús Cruz Rojas, Tuna Demircik, Christian Ecker, Matti Järvinen

AI总结 通过引入带电标量场描述解禁闭相中夸克对的凝聚,扩展全息V-QCD模型,得到了包含一级解禁闭相变及其临界端点以及二级配对-非配对夸克物质相变的相图,并发现均匀配对相的生长速率低于调制相。

Comments 34 pages, 5 figures, 1 appendix

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AI中文摘要

我们通过引入一个带电标量场扇区来表示解禁闭相中配对夸克物质的凝聚,从而扩展了全息V-QCD模型。通过将这个新扇区纳入先前建立的核物质和夸克物质框架,我们得到了一个相图,除了具有一级解禁闭相变及其临界端点外,还显示了配对和非配对夸克物质之间的二级相变。夸克配对的临界温度对化学势的依赖性较弱,可以达到高达$T_\mathrm{crit} \approx 30~ m MeV$的值。比较均匀配对相形成的生长速率与先前发现的调制相的生长速率,表明前者弱于后者。

英文摘要

We extend the holographic V-QCD model by introducing a charged scalar field sector to represent the condensation of paired quark matter in the deconfined phase. By incorporating this new sector into the previously established framework for nuclear and quark matter, we obtain a phase diagram that, in addition to the first-order deconfinement transition and its critical end-point, also features a second-order transition between paired and unpaired quark matter. The critical temperature for quark pairing exhibits only a mild dependence on the chemical potential and can reach values as high as $T_\mathrm{crit} \approx 30~\rm MeV$. Comparison of the growth rate for the formation of homogeneous paired phases to the growth rate of previously discovered modulated phases suggests that the former is subdominant to the latter.

2505.05921 2026-06-03 math.PR math-ph math.MP

Limit Theorems for step reinforced random walks with regularly varying memory

具有正则变化记忆的步增强随机游走的极限定理

Aritra Majumdar, Krishanu Maulik

AI总结 研究步增强随机游走的极限行为,通过线性时间尺度下的几乎必然和L^1收敛的强数定律,以及基于记忆序列有界性的相变,得到扩散或超扩散行为,并发现临界点p_c=(γ+1/2)/(γ+1)处的新现象。

Comments Continuity of the weak limit as a process in the subcritical and the appropriate critical cases under appropriate scalings have been added. Additional Remarks are provided for better understanding. Remarks 2.15 and 5.40 highlights these contributions as well as the choices of the time and the space scalings in comparison to the traditional ones. Remark 2.20 comments on negative reinforcement

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AI中文摘要

对于广义步增强随机游走,从原点出发,第一步根据创新序列的第一个元素进行。在后续时刻,它以与正则变化序列$\{\mu_n\}$(指标$\gamma>-1$)成比例的概率回忆过去时刻;以概率$p$回忆并重复该步,或以概率$1-p$从创新序列中取新步。创新序列假设为独立同分布,均值为零。我们研究相应的步增强随机游走过程,其时间线性缩放为$[0,\infty)$上的r.c.l.l.函数。我们证明了线性缩放过程的强数定律和$L^1$收敛性,适用于所有可能的$p$和$\gamma$值。假设创新序列具有有限二阶矩,我们基于与$\{\mu_n\}$相关的序列的有界性获得了有趣的相变。当该序列有界时,适当缩放的随机游走几乎必然收敛到一个可能非高斯的过程;否则,它依分布收敛到一个高斯过程。这一相变引入了临界点$p_c=\frac{\gamma+1/2}{\gamma+1}$(对于$\gamma>-\frac12$)。在亚临界区域,过程是扩散的;而在超临界区域,过程是超扩散的。然而,在临界区域,缩放过程可以几乎必然收敛或依分布收敛,具体取决于序列$\{\mu_n\}$的选择。临界区域的几乎必然收敛是新的。在临界区域,缩放可以包括除$\sqrt{n \log n}$之外的许多新选择。此外,我们使用线性时间尺度和与时间无关的尺度,即使对于临界区域也是如此。我们认为临界区域的指数时间尺度是不自然的。所有区域中的收敛性都是针对作为r.c.l.l.函数的过程获得的。

英文摘要

For a generalized step reinforced random walk, starting from the origin, the first step is taken according to the first element of an innovation sequence. Then in subsequent epochs, it recalls a past epoch with probability proportional to a regularly varying sequence $\{μ_n\}$ of index $γ>-1$; recalls and repeats the step taken with probability $p$, or with probability $1-p$ takes a fresh step from the innovation sequence. The innovation sequence is assumed to be i.i.d.\ with mean zero. We study the corresponding step reinforced random walk process with linearly scaled time as an r.c.l.l.\ function on $[0, \infty)$. We prove law of large numbers for the linearly scaled process almost surely and in $L^1$ for all possible values of $p$ and $γ$. Assuming finite second moments for the innovation sequence, we obtain interesting phase transitions based on the boundedness of a sequence associated with $\{μ_n\}$. The random walk suitably scaled converges almost surely to a process, which may not be Gaussian, when the sequence is bounded and the convergence is in distribution to a Gaussian process otherwise. This phase transition introduces the point of criticality at $p_c=\frac{γ+1/2}{γ+1}$ for $γ>-\frac12$. For the subcritical regime, the process is diffusive, while it is superdiffusive otherwise. However, for the critical regime, the scaled process can converge almost surely or in distribution depending on the choice of sequence $\{μ_n\}$. Almost sure convergence in the critical regime is new. In the critical regime, the scaling can include many more novel choices in addition to $\sqrt{n \log n}$. Further, we use linear time scale and time independent scales even for the critical regime. We argue the exponential time scale for the critical regime is not natural. All the convergences in all the regimes are obtained for the process as an r.c.l.l.\ function.

2505.04743 2026-06-03 quant-ph

Offline recovery of magic and entanglement from noisy Pauli product states

从噪声泡利乘积态中离线恢复魔力和纠缠

Erika Lloyd, Alexandre Fleury, Marc P. Coons, James Brown, Maritza Hernandez

AI总结 通过经典纯化技术,从泡利乘积公式生成的噪声态中恢复量子计算特有的资源(魔力和纠缠),并发现态内相关性比魔力对噪声更鲁棒,为设计低误差算法提供指导。

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AI中文摘要

量子算法对态保真度的依赖难以解析表征,最好在硬件规模扩大且噪声模拟变得棘手时通过实验探索。虽然低保真度态常被忽略,但只要它们的主本征向量接近目标态,仍可能保留有价值的信息。通过经典纯化,我们展示了从泡利乘积公式(许多量子算法的常见子程序)生成的噪声态中恢复量子计算特有资源(如魔力和纠缠)的能力。此外,我们表明纯化态的保真度取决于魔力和纠缠产生的幅度和顺序,这可用于指导ansatz中算符的顺序。在IonQ的Aria量子设备上的模拟和实验中一致发现,态内的相关性比魔力对噪声更鲁棒,并且我们展示了针对这些低误差态设计算法的优势。本研究使用量子信息工具在噪声框架下分析和优化量子算法。

英文摘要

The dependence of quantum algorithms on state fidelity is difficult to characterize analytically and is best explored experimentally as hardware scales and noisy simulations become intractable. While low fidelity states are often disregarded, they may still retain valuable information, as long as their dominant eigenvector approximates the target state. Through classical purification, we demonstrate the ability to recover resources specific to quantum computing such as magic and entanglement from noisy states generated by Pauli product formulas, which are common subroutines of many quantum algorithms. Additionally we show that the fidelity of the purified state is dependent on both the magnitude and order in which magic and entanglement are generated, which can be used to inform the order of operators within an ansatz. Consistent across simulation and experiment on IonQ's Aria quantum device, correlations within a state are found to be much more robust to noise than magic, and we show the advantage of designing algorithms targeting these low error states. This study uses quantum informatic tools for analyzing and optimizing quantum algorithms in a noisy framework.

1203.5428 2026-06-03 math.NA cond-mat.stat-mech cs.NA physics.chem-ph physics.comp-ph

Rational Construction of Stochastic Numerical Methods for Molecular Sampling

分子采样的随机数值方法的合理构造

Benedict Leimkuhler, Charles Matthews

AI总结 本文通过Baker-Campbell-Hausdorff引理形式展开Langevin动力学数值方法的不变测度,比较不同积分器的不变分布,发现一种方法在高摩擦极限下具有超收敛性(四阶精度),并可简化为Brownian动力学的Euler-Maruyama方法的非马尔可夫修正,在分子模拟中显著提高构型采样精度。

Journal ref Applied Mathematics Research eXpress, Volume 2013, Issue 1, 2013, Pages 34-56

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AI中文摘要

本文关注构型Gibbs-Boltzmann分布的采样,即计算恒定温度下分子N体系统位置坐标函数的平均值。我们展示了如何使用Baker-Campbell-Hausdorff引理直接获得Langevin动力学数值方法不变测度的形式级数展开。然后,我们比较了Langevin动力学积分器的不变分布,并证明了其中一种方法在高摩擦极限下的超收敛性质(预期二阶精度但实际达到四阶精度);此外,该方法可简化为Brownian动力学的Euler-Maruyama方法的简单修正,涉及非马尔可夫(有色噪声)随机过程。在Brownian动力学情况下,不变密度达到二阶精度。所有考虑的方法对于分子应用都是高效的(每步只需一次力评估)且形式简单。在完全解析(长时间运行)的分子动力学模拟中,对于我们偏好的方法,在给定步长下,构型采样精度提高了两个数量级,且与常见替代方法相比,最大可用步长没有明显减小。

英文摘要

In this article, we focus on the sampling of the configurational Gibbs-Boltzmann distribution, that is, the calculation of averages of functions of the position coordinates of a molecular $N$-body system modelled at constant temperature. We show how a formal series expansion of the invariant measure of a Langevin dynamics numerical method can be obtained in a straightforward way using the Baker-Campbell-Hausdorff lemma. We then compare Langevin dynamics integrators in terms of their invariant distributions and demonstrate a superconvergence property (4th order accuracy where only 2nd order would be expected) of one method in the high friction limit; this method, moreover, can be reduced to a simple modification of the Euler-Maruyama method for Brownian dynamics involving a non-Markovian (coloured noise) random process. In the Brownian dynamics case, 2nd order accuracy of the invariant density is achieved. All methods considered are efficient for molecular applications (requiring one force evaluation per timestep) and of a simple form. In fully resolved (long run) molecular dynamics simulations, for our favoured method, we observe up to two orders of magnitude improvement in configurational sampling accuracy for given stepsize with no evident reduction in the size of the largest usable timestep compared to common alternative methods.

math/0605361 2026-06-03 math.PR cs.NA math.NA

Weak approximation of stochastic differential equations and application to derivative pricing

随机微分方程的弱逼近及其在衍生品定价中的应用

Syoiti Ninomiya, Nicolas Victoir

AI总结 本文提出一种新的简单算法用于随机微分方程的弱逼近,并将其应用于Heston随机波动模型下的亚式期权定价,结合拟蒙特卡洛方法显著提高计算速度。

Comments 15 pages, 2 figures, 1 table Minor errors in the numerical expample, fixed

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AI中文摘要

作者提出了一种新的简单算法,用于在[1]和[2]的精神下弱逼近随机微分方程。他们将该算法应用于Heston随机波动模型下的亚式期权定价问题,并与其他已知方法进行了比较。结果表明,该算法与拟蒙特卡洛方法相结合可使计算速度极快。 [1] Shigeo Kusuoka,“扩散过程期望的逼近与数理金融”,《纯数学高级研究》,1998年奈良最终谷口研讨会论文集(T. Sunada编),第31卷,2001年,第147-165页。[2] Terry Lyons和Nicolas Victoir,“Wiener空间上的求体积”,《伦敦皇家学会会刊A辑:数学与物理科学》,第460卷,2004年,第169-198页。

英文摘要

The authors present a new simple algorithm to approximate weakly stochastic differential equations in the spirit of [1] and [2]. They apply it to the problem of pricing Asian options under the Heston stochastic volatility model, and compare it with other known methods. It is shown that the combination of the suggested algorithm and quasi-Monte Carlo methods makes computations extremely fast. [1] Shigeo Kusuoka, ``Approximation of Expectation of Diffusion Process and Mathematical Finance,'' Advanced Studies in Pure Mathematics, Proceedings of Final Taniguchi Symposium, Nara 1998 (T. Sunada, ed.), vol. 31 2001, pp. 147--165. [2] Terry Lyons and Nicolas Victoir, ``Cubature on Wiener Space,'' Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences 460 (2004), pp. 169--198.

2504.16569 2026-06-03 math.AG

The versal deformation of elliptic m-fold point curve singularities

椭圆m重点曲线奇点的通用形变

Jan Stevens

AI总结 本文给出了n维仿射空间中过原点的n+1条直线处于一般位置的奇点L_{n+1}^n的通用形变的显式高度对称方程,并证明了当n>4时其基空间同构于L_n^{n-1}的全空间,进而通过归纳得出基空间不可约且为Gorenstein环,同时讨论了与模空间紧化的联系。

Comments 17 pages

Journal ref Res Math Sci 12, 66 (2025)

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AI中文摘要

我们给出了奇点 $L_{n+1}^n$ 的通用形变的显式、高度对称的方程,该奇点由 n 维仿射空间中处于一般位置的过原点的 n+1 条直线组成。这些方程表明,当 n>4 时,$L_{n+1}^n$ 的通用形变的基空间同构于 $L_n^{n-1}$ 的全空间。通过归纳法,基空间是不可约且 Gorenstein 的。我们讨论了与 genus 1 的 (n+1) 标记曲线模空间的模紧化之间的已知联系。对于其他椭圆划分曲线,通常计算通用形变似乎是不可行的。基空间是否为 Gorenstein 是可疑的。对于有理划分曲线,我们证明基空间通常具有不同维数的分支。

英文摘要

We give explicit, highly symmetric equations for the versal deformation of the singularity $L_{n+1}^n$ consisting of n+1 lines through the origin in n-dimensional affine space in generic position. These make evident that the base space of the versal deformation of $L_{n+1}^n$ is isomorphic to the total space for $L_{n}^{n-1}$, if n>4. By induction it follows that the base space is irreducible and Gorenstein. We discuss the known connection to a modular compactification of the moduli space of (n+1)-pointed curves of genus 1. For other elliptic partition curves it seems unfeasable to compute the versal deformation in general. It is doubtful whether the base space is Gorenstein. For rational partition curves we show that the base space in general has components of different dimensions.

2504.15538 2026-06-03 physics.plasm-ph astro-ph.GA nlin.CD physics.flu-dyn

Local relaxation and scale-dependent alignment in compressible, magnetized turbulence

可压缩磁化湍流中的局域弛豫和尺度依赖的对齐

James R. Beattie, Amitava Bhattacharjee

AI总结 通过高达10,368^3分辨率的驱动净通量和无净通量MHD湍流模拟,发现能量均分尺度以下存在符号混合的速度-磁场、速度-涡度和磁-电流对齐斑块,并建立了预测标度指数的恒定通量输运模型。

Comments 6 pages main text. 3 main figures. 14 pages total. 2 figures in Supp. Material. Submitted to PRL

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AI中文摘要

驱动的净通量和无净通量MHD湍流模拟高达$10,\!368^3$分辨率,揭示了在能量均分尺度以下存在符号混合的速度-磁场、速度-涡度和磁-电流对齐斑块。前两个角度按$λ^{1/8}$和$λ^{1/16}$标度,而磁-电流对齐随尺度变化较弱。我们开发并测试了一个用于偏离弛豫状态的恒定通量输运模型,该模型预测了这两个指数。这些发现影响涡旋各向异性、重联介导的湍流起始、大尺度发电机以及磁化湍流的本质。

英文摘要

Driven net- and no-net-flux MHD turbulence simulations up to $10,\!368^3$ reveal sign-mixed velocity-magnetic, velocity-vorticity, and magnetic-current aligned patches below the energy equipartition scale. The first two angles scale as $λ^{1/8}$ and $λ^{1/16}$, while magnetic-current alignment varies weakly with scale. We develop and test a constant-flux transport model for departures from relaxed states, which predicts both exponents. These findings affect eddy anisotropy, reconnection-mediated turbulence onset, large-scale dynamos, and the nature of magnetized turbulence.

2406.09110 2026-06-03 quant-ph cs.CR

A Practical Protocol for Quantum Oblivious Transfer from One-Way Functions

基于单向函数的量子不经意传输实用协议

Eleni Diamanti, Alex B. Grilo, Adriano Innocenzi, Pascal Lefebvre, Verena Yacoub, Álvaro Yángüez

AI总结 提出一种基于单向函数的量子不经意传输协议,在普通模型中实现模拟安全性,并通过改进效率和提供错误校正分析,促进实验实现。

Comments 31 pages, benchmarking added

Journal ref Quantum 10, 2124 (2026)

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AI中文摘要

我们提出了一种新的基于单向函数的量子不经意传输(QOT)协议,在普通模型中实现了模拟安全性。该协议注重实际实现,在效率上超越了先前的工作,有望实现可行的实验验证。我们处理了潜在实验误差及其校正,并提供了分析表达式以方便所需量子资源的分析。在技术上,我们通过一种模糊且松弛可提取的量子比特承诺实现了QOT的模拟安全性。

英文摘要

We present a new simulation-secure quantum oblivious transfer (QOT) protocol based on one-way functions in the plain model. With a focus on practical implementation, our protocol surpasses prior works in efficiency, promising feasible experimental realization. We address potential experimental errors and their correction, offering analytical expressions to facilitate the analysis of the required quantum resources. Technically, we achieve simulation security for QOT through an equivocal and relaxed-extractable quantum bit commitment.

2502.21184 2026-06-03 math.RT math.CO

Bubble sort and Howe duality for staircase matrices

阶梯矩阵的冒泡排序与Howe对偶

Anton Khoroshkin, Ievgen Makedonskyi

AI总结 本文利用Bruhat偏序集的组合结构和冒泡排序过程,独立证明了阶梯矩阵的Cauchy恒等式,并推广了经典Howe对偶。

Comments Minor correction, polishing some technical proofs

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AI中文摘要

本文利用Bruhat偏序集的组合结构和冒泡排序过程,独立证明了arXiv:2411.03117中最初发现的阶梯矩阵的Cauchy恒等式。此外,我们推导了这些恒等式中出现的某些系数的新见解。论文第一部分聚焦于组合方面,内容自包含且具有独立意义,引入了树状偏序集上单调函数的抛物型Bruhat图的推广。第二部分考察给定可积表示中Demazure模的交集。最后,我们根据相应的Demazure子模分配格提出了阶梯矩阵的经典Howe对偶的推广。计算相关特征标得到所需的阶梯矩阵Cauchy恒等式。

英文摘要

In this paper, we present an independent proof of the Cauchy identities for staircase matrices, originally discovered in arXiv:2411.03117, using the combinatorics of the Bruhat poset and the bubble-sort procedure. Additionally, we derive new insights into certain coefficients appearing in one of these identities. The first part of the paper focuses on combinatorial aspects. It is self-contained, of independent interest, and introduces a generalization of parabolic Bruhat graphs for monotone functions on an arborescent poset. The second part examines the intersections of Demazure modules within a given integrable representation. Finally, we propose a generalization of the classical Howe duality for staircase matrices in terms of the corresponding distributive lattice of Demazure submodules. Computing the associated character yields the desired Cauchy identities for staircase matrices.

2404.06803 2026-06-03 stat.ME math.ST stat.TH

A new way to evaluate G-Wishart normalising constants via Fourier analysis

一种通过傅里叶分析评估G-Wishart归一化常数的新方法

Ching Wong, Giusi Moffa, Jack Kuipers

AI总结 针对贝叶斯高斯图模型中G-Wishart分布归一化常数的计算难题,本文利用随机矩阵理论和傅里叶分析,为非弦图类推导了适合数值计算的新精确结果,并开发了比现有方法高效数个数量级的蒙特卡洛方案。

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AI中文摘要

G-Wishart分布是高斯图模型贝叶斯分析中作为精度矩阵共轭先验的核心组成部分。评估此类模型的边际似然通常需要计算高维积分以确定G-Wishart归一化常数。对于可分解图或弦图,已知有闭式结果,而对于一般图,最近已推导出形式级数展开的显式表示。然而,嵌套无穷和并不适合计算,实际价值有限。借鉴随机矩阵理论和傅里叶分析的技术,我们为弦图之外的图类提供了适合归一化常数数值评估的新精确结果。此外,我们为一般图开发了一种蒙特卡洛方案,其效率可比当前方法高出数个数量级。

英文摘要

The G-Wishart distribution is a core component for the Bayesian analysis of Gaussian graphical models as the conjugate prior for the precision matrix. Evaluating the marginal likelihood of such models usually requires computing high-dimensional integrals to determine the G-Wishart normalising constant. Closed-form results are known for decomposable or chordal graphs, while an explicit representation as a formal series expansion has been derived recently for general graphs. The nested infinite sums, however, do not lend themselves to computation, remaining of limited practical value. Borrowing techniques from random matrix theory and Fourier analysis, we provide novel exact results well suited to the numerical evaluation of the normalising constant for classes of graphs beyond chordal graphs. We additionally develop a Monte Carlo scheme for general graphs, which can be orders of magnitude more efficient than current approaches.

2504.07432 2026-06-03 q-bio.PE

A model for cholera with infectiousness of deceased individuals and vaccination

考虑死者传染性和疫苗接种的霍乱模型

Annour Saad Abdramane, Julien Arino, Patrick M Tchepmo Djomegni, Mahamat S Daoussa Haggar

AI总结 建立了一个包含水源传播、水平传播及死者传染性的霍乱传播模型,研究了环境双稳态与疫苗驱动双稳态的相互作用,并评估了疫苗接种策略、疫苗效力、免疫衰减以及葬礼传播的影响。

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AI中文摘要

本文构建了一个霍乱传播模型,该模型整合了水源传播、水平传播以及死者的传染性。模型考虑了环境中细菌的Allee效应以及不完全和衰减的疫苗接种。研究了模型的数学性质,表明环境双稳态与疫苗驱动的双稳态相结合,尽管对后者的计算搜索未能在现实参数范围内检测到其存在。计算分析还考虑了疫苗接种策略、疫苗效力和衰减之间的相互作用,以及葬礼期间疾病传播的影响。评估了诸如WASH(水、环境卫生和个人卫生)或安全且有尊严的埋葬等控制情景的效果。

英文摘要

A cholera transmission model is formulated that incorporates water-borne and horizontal transmissions as well as infectivity of deceased individuals. The model includes an Allee effect for the bacteria in the environment and imperfect and waning vaccination. Mathematical properties of the model are investigated, with an environmental bistability shown to combine with a vaccine-driven one, although a computational search for the latter fails to detect its presence in realistic parameter ranges. The computational analysis also considers the interplay between vaccination strategy, vaccine efficacy and waning, as well as the effect of transmission of the disease during funeral rites. The effect of control scenarios such as WASH or Safe and dignified burials are assessed.

2504.06981 2026-06-03 eess.SY cs.SY

LCL Resonance Analysis and Damping in Single-Loop Grid-Forming Wind Turbines

单环构网型风力发电机中的LCL谐振分析与阻尼

Meng Chen, Yufei Xi, Frede Blaabjerg, Lin Cheng, Ioannis Lestas

AI总结 本文发现单环构网型控制方案中采用下垂-I控制的无功功率控制会导致开环不稳定极点,揭示了高频稳定性降低的新机制,并提出了相应的有源阻尼设计。

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AI中文摘要

在跟网型和构网型控制系统中,一个常见的假设是它们在高频谐振附近是开环稳定的。因此,经典环路整形方法常用于建立稳定裕度和设计有源阻尼策略。本文表明,采用广泛使用的无功功率控制(称为下垂-I控制)的单环构网型控制方案可能导致开环不稳定极点。这一发现揭示了一种新的不稳定机制,导致高频稳定裕度和鲁棒性降低。详细分析了该现象对无功功率和电气参数的敏感性。提出了一种明确考虑新识别的不稳定机制的有源阻尼设计。我们还提供了此类单环构网型与经过充分研究的跟网型控制方案之间的比较,突出了它们之间截然不同的谐振特性。通过实验进行了验证。

英文摘要

A common assumption in both grid-following (GFL) and grid-forming (GFM) control systems is that they are open-loop (OL) stable in the vicinity of high-frequency resonances. Hence classical loop-shaping approaches are often used for establishing stability margins and designing active damping (AD) strategies. This paper shows that single-loop GFM (SL-GFM) control schemes incorporating a widely used class of reactive power (RAP) control, referred to as droop-I control, can lead to OL unstable poles. This finding reveals a novel instability mechanism resulting in a reduced stability margin and robustness at high frequencies. The sensitivity of this phenomenon to both RAP and electrical parameters is analyzed in detail. An AD design that explicitly accounts for the newly identified instability mechanism is proposed. We also provide a comparison between such SL-GFM and well-studied GFL control schemes, highlighting quite different resonance features between them. Validation is performed through experiments.

2504.04809 2026-06-03 cs.CR

SEEM: Exploiting Black-Box Text Attacks to Manipulate Tool Selection

SEEM:利用黑盒文本攻击操纵工具选择

Liuji Chen, Hao Gao, Jinghao Zhang, Qiang Liu, Shu Wu, Liang Wang

AI总结 提出SEEM方法,通过词级和字符级的粗到细扰动,在黑盒条件下增加目标工具被选中的概率,揭示工具选择机制的安全漏洞。

Comments 2026 IEEE International Conference on Acoustics, Speech, and Signal Processing

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AI中文摘要

工具学习已成为一种强大的辅助机制,扩展了大语言模型(LLM)的能力,使其能够处理需要实时相关性或高精度操作的复杂任务。然而,在这种优势之下隐藏着显著的安全风险。先前的研究主要集中在破坏所调用工具的输出上,而很大程度上忽略了工具选择过程本身的脆弱性。为填补这一空白,我们引入了一种黑盒、基于文本的攻击,该攻击显著增加了目标工具被选中的可能性。我们提出了SEEM,一种在词级和字符级上操作的两级粗到细扰动方法。通过全面的实验,我们表明仅扰动工具的文本信息就能显著提高目标工具在候选工具中被优先考虑和排名更高的概率。我们的发现揭示了工具选择机制中的关键弱点,并为开发防御措施以保护这一关键过程奠定了基础。

英文摘要

Tool learning has emerged as a powerful auxiliary mechanism that extends the capabilities of large language models (LLMs), enabling them to address complex tasks that demand real-time relevance or high-precision operations. However, beneath this strength lie significant security risks. Prior studies have primarily concentrated on corrupting the outputs of invoked tools, while largely overlooking the vulnerability of the tool selection process itself. To bridge this gap, we introduce a black-box, text-based attack that substantially increases the likelihood of a target tool being selected. We propose SEEM, a two-level coarse-to-fine perturbation method that operates at both the word and character levels. Through comprehensive experiments, we show that merely perturbing the textual information of tools can markedly raise the probability of the target tool being prioritized and ranked higher among candidates. Our findings expose critical weaknesses in the tool selection mechanism and lay the groundwork for developing defenses to secure this essential process.

2403.02052 2026-06-03 hep-ph nucl-th

A Global View of the EDM Landscape

电偶极矩景观的全局视角

Skyler Degenkolb, Nina Elmer, Tanmoy Modak, Margarete Mühlleitner, Tilman Plehn

AI总结 本文基于有效量子场论和SFitter全局分析框架,系统解读现有电偶极矩测量对强子尺度拉格朗日量的约束,发现部分参数受限于高精度测量不足,理论不确定性可通过全局分析控制。

Journal ref SciPost Phys. 20, 151 (2026)

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AI中文摘要

永久电偶极矩(EDM)是基本粒子对称性结构的灵敏探针,而对称性结构与宇宙中的重子不对称性密切相关。EDM测量的有意义的解释框架必须基于有效量子场论。我们使用SFitter全局分析框架,以强子尺度拉格朗日量的形式解释迄今为止进行的测量。我们发现该拉格朗日量的部分参数受到很好的约束,而一些参数则因高精度测量不足而受限。理论不确定性导致模型约束较弱,但可以在全局分析中得到控制。

英文摘要

Permanent electric dipole moments (EDMs) are sensitive probes of the symmetry structure of elementary particles, which in turn is closely tied to the baryon asymmetry in the universe. A meaningful interpretation framework for EDM measurements has to be based on effective quantum field theory. We interpret the measurements performed to date in terms of a hadronic-scale Lagrangian, using the SFitter global analysis framework. We find that part of this Lagrangian is constrained very well, while some of the parameters suffer from too few high-precision measurements. Theory uncertainties lead to weaker model constraints, but can be controlled within the global analysis.

2412.19383 2026-06-03 math.AG hep-th math-ph math.MP math.NT math.RT

On the Quantum K-theory of Quiver Varieties at Roots of Unity

单位根处的箭图簇量子K理论

Peter Koroteev, Andrey Smirnov

AI总结 本文证明了Nakajima簇的量子差分方程基本解矩阵在单位根处无极点,并给出了量子连接p-曲率谱的显式描述。

Comments 25 pages, expanded sections 4 and 5, other minor changes

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AI中文摘要

设$Ψ(\textbf{z},\textbf{a},q)$为Nakajima簇$X$的量子差分方程的基本解矩阵。本文证明了算子$$ Ψ(\textbf{z},\textbf{a},q) Ψ\left(\textbf{z}^p,\textbf{a}^p,q^{p^2}\right)^{-1} $$在原始复数$p$次单位根$q=ζ_p$处无极点。作为副产品,我们证明了来自$X$上$q$-差分方程的算子${\bf M}_{\mathcal{L}}(\textbf{z},\textbf{a},q )$的迭代乘积:$$ {\bf M}_{\mathcal{L}} (\textbf{z} q^{(p-1)\mathcal{L}},\textbf{a},q) \cdots {\bf M}_{\mathcal{L}} (\textbf{z} q^{\mathcal{L}},\textbf{a},q) {\bf M}_{\mathcal{L}} (\textbf{z} ,\textbf{a},q) $$在$q=ζ_p$处求值后,与${\bf M}_{\mathcal{L}} (\textbf{z}^p,\textbf{a}^p,q^p)$具有相同的特征值。将$X$的量子差分方程约化为有限特征域上的量子微分方程后,上述迭代乘积转化为相应量子连接的Grothendiek-Katz $p$-曲率,而${\bf M}_{\mathcal{L}} (\textbf{z}^p,\textbf{a}^p,q^p)$成为该连接的某种Frobenius扭曲。由此,我们给出了Nakajima簇量子连接$p$-曲率谱的显式描述。

英文摘要

Let $Ψ(\textbf{z},\textbf{a},q)$ a the fundamental solution matrix of the quantum difference equation of a Nakajima variety $X$. In this work, we prove that the operator $$ Ψ(\textbf{z},\textbf{a},q) Ψ\left(\textbf{z}^p,\textbf{a}^p,q^{p^2}\right)^{-1} $$ has no poles at the primitive complex $p$-th roots of unity $q=ζ_p$. As a byproduct, we show that the iterated product of the operators ${\bf M}_{\mathcal{L}}(\textbf{z},\textbf{a},q )$ from the $q$-difference equation on $X$: $$ {\bf M}_{\mathcal{L}} (\textbf{z} q^{(p-1)\mathcal{L}},\textbf{a},q) \cdots {\bf M}_{\mathcal{L}} (\textbf{z} q^{\mathcal{L}},\textbf{a},q) {\bf M}_{\mathcal{L}} (\textbf{z} ,\textbf{a},q) $$ evaluated at $q=ζ_p$ has the same eigenvalues as ${\bf M}_{\mathcal{L}} (\textbf{z}^p,\textbf{a}^p,q^p)$. Upon a reduction of the quantum difference equation of $X$ to the quantum differential equation over the field of finite characteristic, the above iterated product transforms into a Grothendiek-Katz $p$-curvature of the corresponding quantum connection whreas ${\bf M}_{\mathcal{L}} (\textbf{z}^p,\textbf{a}^p,q^p)$ becomes a certain Frobenius twist of that connection. In this way, we give an explicit description of the spectrum of the $p$-curvature of quantum connection for Nakajima varieties.

2409.12721 2026-06-03 q-fin.CP

Market Simulation under Adverse Selection

逆向选择下的市场模拟

Luca Lalor, Anatoliy Swishchuk

AI总结 针对逆向选择问题,提出考虑成交概率和逆向成交影响的交易策略模拟框架,实证表明该方法能更准确反映策略真实表现。

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AI中文摘要

本文研究了成交概率和逆向成交对交易策略模拟过程的影响。我们特别关注一个随机最优控制做市问题,并在CME(芝加哥商品交易所)上市的最具流动性的期货合约ES(E-mini标普500)、NQ(E-mini纳斯达克100)、CL(原油)和ZN(10年期国债)上测试该策略。我们提供了经验证据,表明成交概率和逆向成交如何显著影响绩效,并提出了一个更审慎的模拟框架来处理这一问题。许多先前的工作旨在衡量限价订单簿(LOB)中不同类型的逆向选择,然而,它们通常独立模拟价格过程和市价订单。这有可能极大地夸大短期交易策略的绩效。我们的研究表明,在策略模拟过程中使用更现实的成交概率并追踪逆向成交,能更准确地显示这些类型的交易策略在现实中的表现。

英文摘要

In this paper, we study the effects of fill probabilities and adverse fills on the trading strategy simulation process. We specifically focus on a stochastic optimal control market-making problem and test the strategy on ES (E-mini S\&P 500), NQ (E-mini Nasdaq 100), CL (Crude Oil) and ZN (10-Year Treasury Note), which are some of the most liquid futures contracts listed on the CME (Chicago Mercantile Exchange). We provide empirical evidence that shows how fill probabilities and adverse fills can significantly affect performance and propose a more prudent simulation framework to deal with this. Many previous works aim to measure different types of adverse selection in the limit order book (LOB), however, they often simulate price processes and market orders independently. This has the ability to largely inflate the performance of a short-term style trading strategy. Our studies show that using more realistic fill probabilities and tracking adverse fills in the strategy simulation process more accurately shows how these types of trading strategies would perform in reality.

2501.19096 2026-06-03 math.GT math.QA

An action of the Witt algebra on Khovanov-Rozansky homology

Witt 代数在 Khovanov-Rozansky 同调上的作用

Alexis Guérin, Felix Roz

AI总结 本文构造了 Witt 代数正部分在 Khovanov-Rozansky gl_N 链环同调上的作用,并证明链环配边诱导同调的扭转之间的等变映射,同时将简单网的状态空间等同于多项式上的标准 Witt 代数表示,由此推导出与 Lee 同调和亏格界的简单关系。

Comments 39 pages, many figures. Revisions throughout. Section 7 was rewritten and expanded

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AI中文摘要

我们构造了 Witt 代数正部分在 Khovanov--Rozansky $\mathfrak{gl}_N$-链环同调上的作用,并证明链环配边诱导同调的扭转之间的等变映射。此外,简单网的状态空间被等同于多项式上的标准 Witt 代数表示。通过分析这一表示,推导出与 Lee 同调和亏格界的一些简单关系。

英文摘要

We construct an action of the positive part of the Witt algebra on Khovanov--Rozansky $\mathfrak{gl}_N$-link homology and show that link cobordisms induce equivariant maps between twists of the homology. Moreover, the state spaces of simple webs are identified with standard representations of the Witt algebra on polynomials. Some simple relations to Lee homology and genus bounds are derived from the analysis of this presentation.

2501.08802 2026-06-03 econ.TH

On the Dominance of Truth-Telling in Gradual Mechanisms

论逐步机制中诚实报告的主导性

Wenqian Wang, Zhiwen Zheng

AI总结 研究在逐步机制中诚实报告何时是占优策略,通过信息集划分的“照明”变换和单一反应无懈条件进行刻画,并应用于二价拍卖和顶级交易循环算法。

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AI中文摘要

近期文献强调了通过动态博弈形式实施社会规则的优势。我们刻画了在实施策略无懈可击的社会规则的逐步机制中,诚实报告何时仍然是占优策略,其中代理人逐步揭示自己的私人信息,同时在此过程中获取关于他人的信息。我们的第一个刻画依赖于对逐步机制的一种基本变换——称为“照明”——的激励保持性,该变换对信息集进行划分。第二个刻画依赖于单一反应无懈条件。我们通过应用于二价拍卖和顶级交易循环算法展示了两种刻画的有用性。

英文摘要

Recent literature highlights the advantages of implementing social rules via dynamic game forms. We characterize when truth-telling remains a dominant strategy in gradual mechanisms implementing strategy-proof social rules, where agents gradually reveal their private information while acquiring information about others in the process. Our first characterization hinges on the incentive-preservation of a basic transformation on gradual mechanisms called illuminating that partitions information sets. The second relies on a single reaction-proofness condition. We demonstrate the usefulness of both characterizations through applications to second-price auctions and the top-trading cycles algorithm.

2503.15046 2026-06-03 math.CO

Refined enumeration of planar Eulerian orientations

平面欧拉定向的精细枚举

Mireille Bousquet-Mélou, Andrew Elvey Price

AI总结 通过组合论证和函数方程,研究四价平面地图欧拉定向按顶点数、交替顶点数和顺时针面数的三参数精细枚举,并求解三种特殊情况。

Comments 65 pages, one Maple session

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AI中文摘要

我们研究四价平面地图的欧拉定向按三个参数的枚举:顶点数、交替顶点数(具有入/出/入/出关联边)和顺时针定向面数。这是Kostov、Zinn-Justin和Elvey Price研究的六顶点模型的细化,其中只考虑前两个参数。通过Ambjorn和Budd的双射,我们的问题等价于一般平面地图的欧拉部分定向的枚举,按边数、无向边数和顶点数计数。我们首先从组合论证推导出刻画关联三变量级数$Q(t,ω,v)$的函数方程组。然后从这个系统推导出该级数的紧凑刻画。我们用它来确定三种双参数情况下的$Q(t,ω,v)$。前两种情况对应于将计数交替顶点(或AB双射后的无向边)的变量$ω$设为$0$或$1$:当$ω=0$时,我们按边和顶点计数一般平面地图的欧拉定向;当$ω=1$时,我们按顶点和顺时针面计数四次地图的欧拉定向。这两个级数$Q(t,0,v)$和$Q(t,1,v)$的最终形式细化了作者在早期论文中针对$v=1$得到的结果。我们解决的第三种情况,即$v=1$(但$ω$任意),是标准的六顶点模型,我们为其提供了Elvey Price和Zinn-Justin涉及Jacobi theta函数的公式的新证明。这个新推导仍然纯粹在形式幂级数的世界中,不依赖于复分析。我们的结果还使用了更直接的方法来求解函数方程,与先前工作中使用的猜测和检查方法形成对比。

英文摘要

We address the enumeration of Eulerian orientations of 4-valent planar maps according to three parameters: the number of vertices, the number of alternating vertices (having in/out/in/out incident edges), and the number of clockwise oriented faces. This is a refinement of the six vertex model studied by Kostov, then Zinn-Justin and Elvey Price, where one only considers the first two parameters. Via a bijection of Ambjorn and Budd, our problem is equivalent to the enumeration of Eulerian partial orientations of general planar maps, counted by the number of edges, the number of undirected edges, and the number of vertices. We first derive from combinatorial arguments a system of functional equations characterising the associated trivariate series $Q(t,ω,v)$. We then derive from this system a compact characterisation of this series. We use it to determine $Q(t,ω,v)$ in three two-parameter cases. The first two cases correspond to setting the variable $ω$ counting alternating vertices (or undirected edges after the AB bijection) to $0$ or $1$: when $ω=0$ we count Eulerian orientations of general planar maps by edges and vertices, and when $ω=1$ we count Eulerian orientations of quartic maps by vertices and clockwise faces. The final forms of these two series, namely $Q(t,0, v)$ and $Q(t,1,v)$, refine those obtained by the authors in an earlier paper for $v=1$. The third case that we solve, namely $v=1$ (but $ω$ arbitrary), is the standard six-vertex model, for which we provide a new proof of the formula of Elvey Price and Zinn-Justin involving Jacobi theta functions. This new derivation remains purely in the world of formal power series, not relying on complex analysis. Our results also use a more direct approach to solving the functional equations, in contrast to the guess and check approaches used in previous work.

2406.11479 2026-06-03 math.NT

A proof of Sugawara's conjecture on Hasse-Weber ray class invariants

Sugawara关于Hasse-Weber射线类不变量的猜想的证明

Patrick Morton

AI总结 本文证明了Sugawara于1936年提出的猜想:虚二次域K上导子f的射线类域可由单个原始的f-分点τ函数值在K上生成。

Comments 81 pages; corrections have been made to Section 6.2; and an appendix has been added

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AI中文摘要

本文给出了Sugawara 1936年猜想的证明,即虚二次域K上导子$\mathfrak{f}$的射线类域可由单个原始的$\mathfrak{f}$-分点$\tau$-函数值在K上生成,该函数最初由Weber定义,后由Hasse在其1927年论文中修改,为复乘法提供了新基础。

英文摘要

In this paper a proof is given of Sugawara's conjecture from 1936, that the ray class field of conductor $\mathfrak{f}$ over an imaginary quadratic field $K$ is generated over $K$ by a single primitive $\mathfrak{f}$-division value of the $τ$-function, first defined by Weber and then modified by Hasse in his 1927 paper giving a new foundation of complex multiplication.

2503.05647 2026-06-03 quant-ph

Phase estimation with partially randomized time evolution

部分随机化时间演化的相位估计

Jakob Günther, Freek Witteveen, Alexander Schmidhuber, Marek Miller, Matthias Christandl, Aram Harrow

AI总结 本文提出部分随机化的哈密顿量模拟方法,通过将部分项确定性处理、其余项随机采样,加速量子相位估计中的乘积公式,在量子化学基准系统中实现数量级改进,并展示与最优量子化方法竞争的系统规模渐近标度。

Comments 42 pages, 19 figures

Journal ref PRX Quantum 7, 020332, 2026

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AI中文摘要

量子相位估计结合哈密顿量模拟是在量子计算机上计算基态能量最有前景的算法框架。其主要计算开销来自哈密顿量子程序。本文利用随机化加速乘积公式(哈密顿量模拟的标准方法之一)。我们提出了新的部分随机化哈密顿量模拟方法,其中一些项保持确定性处理,另一些项随机采样。我们针对量子化学中的基准系统,使用部分随机化乘积公式对单辅助比特相位估计进行了详细的资源估计,与其他基于乘积公式的模拟相比,获得了数量级的改进。当应用于氢链时,我们的数值证据表明,我们的方法在系统规模上的渐近标度与已知最优的量子化方法相当。

英文摘要

Quantum phase estimation combined with Hamiltonian simulation is the most promising algorithmic framework to computing ground state energies on quantum computers. Its main computational overhead derives from the Hamiltonian simulation subroutine. In this paper we use randomization to speed up product formulas, one of the standard approaches to Hamiltonian simulation. We propose new partially randomized Hamiltonian simulation methods in which some terms are kept deterministically and others are randomly sampled. We perform a detailed resource estimate for single-ancilla phase estimation using partially randomized product formulas for benchmark systems in quantum chemistry and obtain orders-of-magnitude improvements compared to other simulations based on product formulas. When applied to the hydrogen chain, we have numerical evidence that our methods exhibit asymptotic scaling with the system size that is competitive with the best known qubitization approaches.

2503.05364 2026-06-03 math.LO cs.LO

Classical Logic as Intuitionistic Logic with Duality

经典逻辑作为带对偶性的直觉主义逻辑

Alexander V. Gheorghiu, Yll Buzoku

AI总结 本文通过将原子命题替换为字面量并引入原始对偶性,提出一种基于证明论语义的经典逻辑替代方案,表明经典逻辑可视为直觉主义逻辑加上对偶性原则。

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AI中文摘要

证明论语义(P-tS)领域提供了一种基于推理和论证(而非模型中的真值)的逻辑意义替代方法。它已成功应用于多种逻辑;特别是,Sandqvist 为经典逻辑和直觉主义逻辑都开发了这样的语义。在经典逻辑的情况下,P-tS 提供了一种避免先验承诺二值原则的后果概念,解决了 Dummett 所认定的逻辑中一个重大的基础性挑战。在本文中,我们提出了一种替代的经典逻辑 P-tS,它本质上扩展了直觉主义逻辑的 P-tS,通过操作字面量而非原子命题。重要的是,字面量是原子的,并非由否定定义,而是通过原子层面推理编码的原始对偶性相关联。这种语义阐明了经典逻辑可以被理解为直觉主义逻辑加上对偶性原则的观点,为这两个系统之间的关系提供了新的见解。

英文摘要

The field of proof-theoretic semantics (P-tS) offers an alternative approach to meaning in logic that is based on inference and argument (rather than truth in a model). It has been successfully developed for various logics; in particular, Sandqvist has developed such semantics for both classical and intuitionistic logic. In the case of classical logic, P-tS provides a conception of consequence that avoids an a priori commitment to the principle of bivalence, addressing what Dummett identified as a significant foundational challenge in logic. In this paper, we propose an alternative P-tS for classical logic, which essentially extends the P-tS for intuitionistic logic by operating over literals rather than atomic propositions. Importantly, literals are atomic and not defined by negation but are related by a primitive duality encoded inferentially at the atomic level. This semantics illustrates the perspective that classical logic can be understood as intuitionistic logic supplemented by a principle of duality, offering fresh insights into the relationship between these two systems.

2502.21167 2026-06-03 math.DS q-bio.MN

Decomposable and essentially univariate mass-action systems: Extensions of the deficiency one theorem

可分解且本质上单变量的质量作用系统:亏数一定理的推广

Abhishek Deshpande, Stefan Müller

AI总结 本文通过引入单项式依赖概念,将亏数一定理推广到允许子网络具有任意亏数和任意数量吸收强成分的质量作用系统,并证明了更一般的依赖一定理。

Comments 37 pages, 1 table, 3 figures, 3 diagrams

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AI中文摘要

Feinberg 的经典和扩展亏数一定理适用于具有质量作用动力学的反应网络,这些网络具有独立的连接类或子网络,每个子网络的亏数至多为1且恰好有一个吸收强成分。该定理假设存在正平衡,并保证在每个化学计量相容性类中存在唯一的正平衡。在我们的工作中,我们使用$\textit{单项式依赖}$来扩展亏数的概念。首先,我们为本质上单变量且可分解的参数化多项式方程组提供了一个依赖一定理。作为主要结果,我们给出了质量作用系统的相应定理,该定理允许子网络具有任意亏数和任意数量的吸收强成分。最后,为了完善图像,我们将扩展的亏数一定理推导为我们更一般的依赖一定理的特例。

英文摘要

The classical and extended deficiency one theorems by Feinberg apply to reaction networks with mass-action kinetics that have independent linkage classes or subnetworks, each with a deficiency of at most one and exactly one absorbing strong component. The theorems assume the existence of a positive equilibrium and guarantee the existence of a unique positive equilibrium in every stoichiometric compatibility class. In our work, we use the $\textit{monomial dependency}$ which extends the concept of deficiency. First, we provide a dependency one theorem for parametrized systems of polynomial equations that are essentially univariate and decomposable. As our main result, we present a corresponding theorem for mass-action systems, which permits subnetworks with arbitrary deficiency and arbitrary number of absorbing strong components. Finally, to complete the picture, we derive the extended deficiency one theorem as a special case of our more general dependency one theorem.

1011.4237 2026-06-03 eess.SY cs.SY math.OC

A variational and symplectic framework for model-free control: preliminary results

无模型控制的变分与辛框架:初步结果

Loïc Michel

AI总结 本文提出一种基于变分法和辛结构的无模型控制自适应框架,通过优化控制器关键参数提高跟踪鲁棒性和闭环稳定性。

Comments 7 pages, 13 figures - submitted to IEEE CCTA'25

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AI中文摘要

无模型控制方法是一种先进的控制律,只需很少的过程信息即可进行控制。自2008年提出以来,已成功应用于众多领域,展现出对跟踪效率和干扰抑制的鲁棒性。本文提出无模型控制的变分方法以扩展其鲁棒性能力。利用辛框架下的变分法,提出控制器的自适应公式,将控制律视为优化问题以实现其主要关键参数的自整定。所提公式将无模型控制律与变分积分器耦合,以提高对过程变化的跟踪鲁棒性并强调闭环稳定性。通过一些示例讨论以证明所提方法的正确性。

英文摘要

The model-free control approach is an advanced control law that requires few information about the process to control. Since its introduction in 2008, numerous applications have been successfully considered, highlighting attractive robustness properties towards tracking efficiency and disturbance rejection. In this work, a variational approach of the model-free control is proposed in order to extend its robustness capabilities. An adaptive formulation of the controller is proposed using the calculus of variations within a symplectic framework, that aims to consider the control law as an optimization problem toward the auto-tuning of its main key parameter. The proposed formulation provides a coupling between the model-free control law and a variational integrator to improve the robustness of the tracking towards process changes and emphasize closed-loop stabilization. Some illustrative examples are discussed to highlight the rightness of the proposed approach.

2502.12457 2026-06-03 math.AP

Well-Posedness and Asymptotic Decay of Solutions to the Three-Dimensional Euler Equations with Damping

带阻尼的三维欧拉方程解的适定性和渐近衰减

Gui-Qiang G. Chen, Feimin Huang, Houzhi Tang, Shuxing Zhang, Weiyuan Zou

AI总结 针对等熵(γ>1)和等温(γ=1)情形,在初始数据部分大(L²范数大但三阶Sobolev范数小)条件下,证明了带阻尼的三维可压缩欧拉方程柯西问题的全局适定性和最优代数衰减率,并建立了等温极限。

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AI中文摘要

带阻尼的多维可压缩欧拉方程的全局适定性仍然是一个长期未解决的开放问题。该问题在等熵情形(即绝热指数γ>1)下对于小光滑初始数据已部分解决(参见文献\cite{WY, STW})。本文针对等熵情形γ>1和等温情形γ=1,建立了带阻尼的三维可压缩欧拉方程柯西问题光滑解的全局适定性和渐近衰减,允许初始数据部分大。更精确地说,初始数据的L²范数可以很大,而初始数据的三阶Sobolev范数假设很小。对于等熵情形,我们发展了一个新的分析框架,在该框架下,只要∫_0^T (‖∇ρ‖_{L^∞} + ‖∇u‖_{L^∞}) dt保持足够小,就可以导出解(ρ,u)所需的所有先验估计。此外,我们得到了全局解的最优代数衰减率。进一步,我们研究了等熵情形解当γ→1时的等温极限,并建立了带阻尼的等温欧拉方程解的全局适定性和渐近衰减。

英文摘要

The global well-posedness of the multi-dimensional compressible Euler equations with damping remains a longstanding open problem. This problem has been partially resolved in the isentropic regime ({\it i.e.}, the adiabatic exponent \(γ>1\)) for small smooth initial data (see \cite{WY, STW}). In this paper, we establish the global well-posedness and asymptotic decay of smooth solutions of the Cauchy problem of the three-dimensional compressible Euler equations with damping for the isentropic regime \(γ>1\) and the isothermal regime \(γ=1\), allowing for partially large initial data. More precisely, the \(L^2\)-norm of the initial data is allowed to be large, while the third-order Sobolev norm of the initial data is assumed to be small. For the isentropic case, we develop a new analytical framework in which all required {\it a priori} estimates of solution $(ρ,u)$ can be derived under the condition that $\int_0^T \big( \|\nablaρ\|_{L^\infty} + \|\nabla u\|_{L^\infty} \big) \, \mathrm{d}t$ remains sufficiently small. Moreover, we obtain the optimal algebraic decay rates of global solutions. Furthermore, we study the isothermal limit of solutions of the isentropic regime as $γ\to 1$, and establish the global well-posedness and asymptotic decay of solutions to the isothermal Euler equations with damping.

2406.05242 2026-06-03 stat.CO stat.ME stat.ML

Markov chain Monte Carlo without evaluating the target: an auxiliary variable approach

无需评估目标的马尔可夫链蒙特卡洛:一种辅助变量方法

Wei Yuan, Guanyang Wang

AI总结 针对目标分布难以评估的采样问题,提出一种统一的辅助变量MCMC框架,利用估计梯度指导提议移动,显著提升性能。

Comments ICML 2026 oral. Code: https://github.com/ywwes26/Auxiliary-MCMC

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AI中文摘要

在采样任务中,目标分布通常已知到归一化常数。然而,在许多情况下,即使评估未归一化的分布也可能是昂贵或不可行的。这个问题出现在诸如从大数据集的贝叶斯后验和“双重难处理”分布中采样等场景。在本文中,我们首先观察到看似不同的马尔可夫链蒙特卡洛(MCMC)算法,如交换算法、PoissonMH和TunaMH,可以在一个简单的共同程序下统一。然后,我们将该程序扩展为一个新颖的框架,允许在提议和接受-拒绝步骤中使用辅助变量。从这个框架中涌现出几种新的MCMC算法,它们使用估计梯度来指导提议移动。在合成和真实数据集上,它们表现出比现有方法显著更好的性能。我们还为新框架开发了理论,并用它来简化和扩展现有算法的结果。重现实验结果的代码可在https://github.com/ywwes26/Auxiliary-MCMC找到。

英文摘要

In sampling tasks, it is common for target distributions to be known up to a normalizing constant. However, in many situations, even evaluating the unnormalized distribution can be costly or infeasible. This issue arises in scenarios such as sampling from the Bayesian posterior for tall datasets and the `doubly-intractable' distributions. In this paper, we begin by observing that seemingly different Markov chain Monte Carlo (MCMC) algorithms, such as the exchange algorithm, PoissonMH, and TunaMH, can be unified under a simple common procedure. We then extend this procedure into a novel framework that allows the use of auxiliary variables in both the proposal and the acceptance--rejection step. Several new MCMC algorithms emerge from this framework that uses estimated gradients to guide the proposal moves. They have demonstrated significantly better performance than existing methods on both synthetic and real datasets. We also develop theory for the new framework and use it to simplify and extend results for existing algorithms. The code to reproduce the experimental results can be found at https://github.com/ywwes26/Auxiliary-MCMC.

2501.15983 2026-06-03 gr-qc

Rotating and non-linear magnetic-charged black hole with an anisotropic matter field

带有各向异性物质场的旋转非线性磁荷黑洞

Qi-Quan Li, Yu Zhang, Hoernisa Iminniyaz

AI总结 通过改进的Newman-Janis算法,构造了带有各向异性物质场的非线性磁荷黑洞及其旋转解,研究了其几何性质、热力学和彭罗斯过程。

Comments 12 pages, 6 figures

Journal ref Chinese Physics C, Vol. 49, No. 10 (2025) 105106

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AI中文摘要

我们给出了带有各向异性物质场的非线性磁荷黑洞的解,并进一步利用改进的Newman-Janis算法将其推广到相应的旋转黑洞解。从几何性质的角度研究了旋转黑洞的事件视界和能层,揭示了旋转黑洞最多可以有三个视界。从热力学角度推导了旋转黑洞的热力学第一定律和平方质量公式,在此基础上得到了热力学量并研究了旋转黑洞的热力学稳定性。此外,我们计算了旋转黑洞的彭罗斯过程,表明了各种黑洞参数对彭罗斯过程最大效率的影响。

英文摘要

We present the solution of a non-linear magnetic-charged black hole with an anisotropic matter field and further extend it to obtain the corresponding rotating black hole solution using the modified Newman-Janis algorithm. The event horizon and ergosphere of the rotating black hole are studied in terms of the perspective of geometric properties, revealing that the rotating black hole can have up to three horizons. The first law of thermodynamics and the squared-mass formula for the rotating black hole are derived from a thermodynamic perspective, based on which we obtain the thermodynamic quantities and study the thermodynamic stability of the rotating black hole. Additionally, we calculate the Penrose process for the rotating black hole, indicating the influence of various black hole parameters on the maximal efficiency of the Penrose process.

2501.14979 2026-06-03 physics.acc-ph physics.soc-ph

High-level environmental sustainability guidelines for large accelerator facilities

大型加速器设施的高层级环境可持续性指南

Hannah Wakeling, Philip Burrows, Jim Clarke, Jo Colwell, Niko Neufeld, Ben Shepherd, Dwayne Spiteri, John Thomason

AI总结 本文针对未来大型加速器设施的设计、建造、运行和退役阶段,提出高层级环境可持续性指南,旨在通过嵌入创新减排技术降低环境影响。

Comments 55 pages, 1 figure. Living document, version 2

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AI中文摘要

未来几十年拟建的新型粒子加速器设施——以及对现有设施的升级——为将创新的环境影响减少技术嵌入其设计提供了独特的机会。这份动态文档提供了高层级指南,旨在改善大型加速器设施在规划、建造、运行和退役阶段的环境可持续性。文中提供了各种资源集合,并附有现有和推荐实践的例子。

英文摘要

The proposed construction of new particle accelerator-based facilities in the coming decades -- and upgrades to existing facilities -- provides the unique opportunity to embed innovative environmental impact reduction techniques into their design. This living document provides high-level guidelines to improve environmental sustainability in the planning, construction, operational and decommissioning stages of large accelerator facilities. A collection of various resources is provided, with examples of some existing and suggested practices.

2407.21431 2026-06-03 math.NT math.AG

On $μ$-invariants and isogenies for abelian varieties over function fields

关于函数域上阿贝尔簇的$\mu$-不变量和同源

Sohan Ghosh, Jishnu Ray, Takashi Suzuki

AI总结 本文给出了函数域上阿贝尔簇在非分歧$\mathbb{Z}_{p}$扩张中Iwasawa $\mu$-不变量在同源下的变化公式,并证明了Birch--Swinnerton-Dyer猜想在同源下的不变性。

Comments Revised after referee report. 26 pages

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AI中文摘要

我们给出了函数域上阿贝尔簇在非分歧$\mathbb{Z}_{p}$扩张中Iwasawa $\mu$-不变量在同源下变化的几个公式。这些是数域情形下Schneider公式的类比。我们还证明了函数域上Birch--Swinnerton-Dyer猜想(包括首项系数公式)在同源下成立的不变性,而不使用Kato--Trihan的结果。

英文摘要

We give several formulas for how Iwasawa $μ$-invariants of abelian varieties over unramified $\mathbb{Z}_{p}$-extensions of function fields change under isogeny. These are analogues of Schneider's formula in the number field setting. We also prove that the validity of the Birch--Swinnerton-Dyer conjecture (including the leading coefficient formula) over function fields is invariant under isogeny, without using the result of Kato--Trihan.