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2605.21436 2026-05-21 astro-ph.CO

Euclid preparation: Testing multi-field inflation with galaxy power spectrum and bispectrum

Euclid准备:利用星系功率谱和双谱测试多场膨胀

Euclid Collaboration, D. Linde, A. Moradinezhad Dizgah, G. Parimbelli, K. Pardede, E. Sefusatti, M. S. Cagliari, G. D'Amico, V. Desjacques, A. Eggemeier, M. Biagetti, A. Veropalumbo, B. Camacho Quevedo, A. Chudaykin, M. Crocce, L. Castiblanco, E. Castorina, A. Farina, M. Guidi, M. Karcher, A. Pezzotta, A. Pugno, B. Altieri, S. Andreon, N. Auricchio, C. Baccigalupi, M. Baldi, S. Bardelli, P. Battaglia, A. Biviano, E. Branchini, M. Brescia, S. Camera, G. Canas-Herrera, V. Capobianco, C. Carbone, J. Carretero, S. Casas, M. Castellano, G. Castignani, S. Cavuoti, K. C. Chambers, A. Cimatti, C. Colodro-Conde, G. Congedo, L. Conversi, Y. Copin, F. Courbin, H. M. Courtois, H. Degaudenzi, S. de la Torre, G. De Lucia, H. Dole, M. Douspis, F. Dubath, X. Dupac, S. Escoffier, M. Farina, R. Farinelli, S. Ferriol, F. Finelli, P. Fosalba, S. Fotopoulou, M. Frailis, M. Fumana, S. Galeotta, K. George, B. Gillis, C. Giocoli, J. Gracia-Carpio, A. Grazian, F. Grupp, S. V. H. Haugan, W. Holmes, F. Hormuth, A. Hornstrup, K. Jahnke, B. Joachimi, S. Kermiche, A. Kiessling, B. Kubik, M. Kunz, H. Kurki-Suonio, A. M. C. Le Brun, S. Ligori, P. B. Lilje, V. Lindholm, I. Lloro, G. Mainetti, O. Mansutti, O. Marggraf, M. Martinelli, N. Martinet, F. Marulli, R. J. Massey, E. Medinaceli, S. Mei, M. Meneghetti, E. Merlin, G. Meylan, A. Mora, M. Moresco, L. Moscardini, C. Neissner, S. -M. Niemi, J. W. Nightingale, C. Padilla, S. Paltani, F. Pasian, K. Pedersen, W. J. Percival, V. Pettorino, S. Pires, G. Polenta, M. Poncet, L. A. Popa, F. Raison, A. Renzi, J. Rhodes, G. Riccio, E. Romelli, M. Roncarelli, R. Saglia, Z. Sakr, A. G. Sanchez, D. Sapone, B. Sartoris, A. Secroun, G. Seidel, E. Sihvola, P. Simon, C. Sirignano, G. Sirri, A. Spurio Mancini, L. Stanco, P. Tallada-Crespi, A. N. Taylor, I. Tereno, N. Tessore, S. Toft, R. Toledo-Moreo, F. Torradeflot, I. Tutusaus, L. Valenziano, J. Valiviita, T. Vassallo, G. Verdoes Kleijn, Y. Wang, J. Weller, G. Zamorani, F. M. Zerbi, E. Zucca, M. Ballardini, E. Bozzo, C. Burigana, R. Cabanac, M. Calabrese, T. Castro, J. A. Escartin Vigo, J. Garcia-Bellido, J. Macias-Perez, R. Maoli, J. Martin-Fleitas, N. Mauri, R. B. Metcalf, P. Monaco, M. Pontinen, I. Risso, V. Scottez, M. Sereno, M. Tenti, M. Tucci, M. Viel, M. Wiesmann, Y. Akrami, I. T. Andika, G. Angora, M. Archidiacono, F. Atrio-Barandela, S. Avila, L. Bazzanini, J. Bel, D. Bertacca, M. Bethermin, F. Beutler, A. Blanchard, L. Blot, H. Bohringer, M. Bonici, S. Borgani, M. L. Brown, S. Bruton, A. Calabro, F. Caro, C. S. Carvalho, F. Cogato, A. R. Cooray, S. Davini, G. Desprez, A. Diaz-Sanchez, S. Di Domizio, J. M. Diego, V. Duret, M. Y. Elkhashab, A. Enia, Y. Fang, A. Finoguenov, A. Franco, K. Ganga, T. Gasparetto, F. Giacomini, F. Gianotti, G. Gozaliasl, A. Gruppuso, C. M. Gutierrez, A. Hall, C. Hernandez-Monteagudo, H. Hildebrandt, J. Hjorth, J. J. E. Kajava, Y. Kang, V. Kansal, D. Karagiannis, K. Kiiveri, J. Kim, C. C. Kirkpatrick, S. Kruk, M. Lattanzi, L. Legrand, M. Lembo, F. Lepori, G. Leroy, G. F. Lesci, J. Lesgourgues, T. I. Liaudat, S. J. Liu, G. Maggio, M. Magliocchetti, A. Manjon-Garcia, F. Mannucci, C. J. A. P. Martins, L. Maurin, C. Moretti, G. Morgante, S. Nadathur, K. Naidoo, A. Navarro-Alsina, S. Nesseris, L. Pagano, D. Paoletti, F. Passalacqua, K. Paterson, L. Patrizii, C. Pattison, A. Pisani, D. Potter, G. W. Pratt, S. Quai, M. Radovich, K. Rojas, W. Roster, S. Sacquegna, M. Sahlen, D. B. Sanders, E. Sarpa, A. Schneider, M. Schultheis, D. Sciotti, E. Sellentin, L. C. Smith, K. Tanidis, F. Tarsitano, G. Testera, R. Teyssier, S. Tosi, A. Troja, A. Venhola, D. Vergani, F. Vernizzi, G. Verza, S. Vinciguerra, N. A. Walton, A. H. Wright, H. W. Yeung

AI总结 本文基于Euclid任务的观测需求,通过验证基于红移空间功率谱和双谱的分析管道,利用Abacus-PNG N-body模拟中的Gaussian和local-PNG初始条件,测试多场膨胀,通过双谱约束其他PNG组合以缓解退化,并提出基于物理的先验分布以获得无偏f_NL。

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AI中文摘要

原始非高斯性(PNG)是探测宇宙结构起源的强大探针。阶段IV调查如Euclid将测量高信噪比下的星系2点和3点聚类,其利用需要稳健的联合分析。我们通过在Abacus-PNG N-body模拟中使用Gaussian和local-PNG初始条件的Euclid-like mocks上验证了一个红移空间功率谱和双谱管道(one-loop P_ℓ,tree-level B_ℓ)来准备Euclid的光谱样本。我们通过压力测试分析选择——PNG偏差参数化、先验和尺度切割——并进行无PNG的零测试。在“先验无关设置”中,单红移bin中主导PNG项∝f_NL b_ϕ的检测困难;然而,双谱对其他PNG组合提供约束,部分缓解退化。我们提出一个基于物理的先验分布,以获得无偏f_NL的同时考虑理论不确定性,并确定尺度切割,以获得无偏ΛCDM和f_NL。在四个快照(0.8≤z≤1.7)中,有效体积V_eff=16h^{-3}Gpc^3,我们的似然分析恢复f_NL和ΛCDM的<1σ偏移。在固定切割下,B_ℓ单独将σ(f_NL)减少约29-46%,相对于P_ℓ,联合功率谱-双谱分析进一步收紧约8-13%;从z=0到1.7的累积增益约为2.3(联合情况)。双谱四极距是关键。我们最强的结果出现在z=1.7:1.9σ for f_NL b_ϕ(先验无关)和2.35σ for f_NL(先验基于)。因此,联合分析提供了测试多场膨胀的强烈前景,有待在完整的Euclid几何中进行端到端验证以考虑观测系统误差。

英文摘要

Primordial non-Gaussianity (PNG) is a powerful probe of the origin of cosmic structure. Stage-IV surveys like \Euclid will measure galaxy $2$- and $3$-point clustering at high signal-to-noise, whose exploitation requires robust joint analysis. We prepare for Euclid's spectroscopic sample by validating a redshift-space power-spectrum and bispectrum pipeline (one-loop $P_\ell$, tree-level $B_\ell$) on Euclid-like mocks from Abacus-PNG $N$-body simulations with Gaussian and local-PNG initial conditions, using a halo occupation distribution (HOD) tuned to Euclid Flagship 2. We stress-test analysis choices -- PNG-bias parametrisation, priors, and scale cuts -- and perform null tests without PNG. In a `prior-agnostic setup', detection of the dominant PNG term $\propto f_{\rm NL} \, b_ϕ$ in single redshift bins is difficult; nevertheless, the bispectrum provides constraints on other PNG combinations that partially lift degeneracies. We propose a physically motivated prior on $b_ϕ$ that yields unbiased $f_{\rm NL}$ while accounting for theory uncertainty, and determine scale cuts that give unbiased $Λ$CDM and $f_{\rm NL}$. With $V_{\rm eff}=16\,h^{-3}\,{\rm Gpc}^3$ across four snapshots ($0.8\le z\le1.7$), our likelihood analyses recover $<1σ$ bias in $f_{\rm NL}$ and $Λ$CDM. At fixed cuts, $B_\ell$ alone reduces $σ({f_{\rm NL}})$ by $\sim29$--$46\%$ relative to $P_\ell$, and joint power spectrum-bispectrum analysis tightens a further $\sim8$--$13\%$; the cumulative gain from $z=0.8$ to $1.7$ is $\sim2.3$ for the joint case. The bispectrum quadrupole is key. Our strongest results are at $z=1.7$: $1.9σ$ for $f_{\rm NL} \, b_ϕ$ (prior-agnostic) and $2.35σ$ for $f_{\rm NL}$ (prior-based). Joint analyses thus offer strong prospects for testing multi-field inflation, pending end-to-end validation in the full Euclid geometry with observational systematics.

2605.21434 2026-05-21 cs.SE

Agentic Model Checking

代理模型检查

Youcheng Sun, Jiawen Liu, Daniel Kroening, Jason Xue

AI总结 本文提出了一种代理模型检查方法,结合LLM代理与受限模型检查后端,通过代理提出任务并由求解器验证,以解决LLM生成系统代码的验证难题,包括规范缺失和安全合同隐式编码的问题。

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AI中文摘要

验证LLM生成的系统代码具有挑战性:bug普遍存在,形式化规范缺失,且安全合同在调用站点隐式编码而非在函数边界强制执行。我们提出了代理模型检查,一种将LLM代理与受限模型检查后端结合的范式,基于代理提出、求解器验证的原则:代理处理需要语义判断的任务(规范推断、检查选择、反例分类、细化建议),而BMC处理所有与正确性相关决策。该范式基于三个承诺:规范从调用者上下文自顶向下推断,使用受限的DSL,确定性地转换为后端的assume/assert原语,可选的功能正确性条款将验证从无恐慌性提升到行为忠实性。验证是组合的:每个函数独立检查其规范,调用者替换为后置条件约束的占位符,因此每次查询的成本与单个函数的状态空间成比例,细化自动传播到调用者。反例不是bug报告:它们通过验证流水线(可达性、调用者可行性、动态回放、现实审计)区分活跃的树内崩溃与潜在的公共API故障,同时建模艺术驱动细化循环而非被抑制。我们实例化该方法为BMC-Agent,并在C和Rust生成的内核和编译器代码以及成熟的OSS-Fuzz加固库上评估,确认了真实缺陷,生成了在高度模糊化表面的有界干净验证,并在选定的算法函数上建立了功能等价性。

英文摘要

Verifying LLM-generated systems code is hard: bugs are prevalent, formal specifications are missing, and safety contracts are encoded implicitly at call sites rather than enforced at function boundaries. We propose agentic model checking, a paradigm that couples LLM agents with a bounded model checking backend under the principle agents propose, solvers verify: agents handle tasks requiring semantic judgment (spec inference, check selection, counterexample classification, refinement proposal) while BMC discharges every soundness-relevant decision. The paradigm rests on three commitments. Specifications are inferred top-down from caller context in a restricted DSL that translates deterministically into the backend's assume/assert primitives, with optional functional-correctness clauses lifting verification from panic-freeness to behavioural faithfulness. Verification is compositional: each function is checked in isolation against its spec with callees replaced by postcondition-constrained stubs, so per-query cost scales with a single function's state space and refinements propagate automatically to callers. Counterexamples are not bug reports: they pass through a validation pipeline (reachability, callee feasibility, dynamic replay, realism audit) that distinguishes active in-tree crashes from latent public-API failures, while modelling artifacts drive a refinement loop rather than being suppressed. We instantiate the approach in BMC-Agent and evaluate it on LLM-generated kernel and compiler code in C and Rust alongside mature OSS-Fuzz-hardened libraries, confirming real defects, producing bounded clean verifications on heavily-fuzzed surfaces, and establishing functional equivalence on selected algorithmic functions.

2605.21432 2026-05-21 physics.optics

Intraband and Interband Competition Drives Ultrafast Modulations of Indium Tin Oxide

In带内和带间竞争驱动氧化铟锡的超快调制

Anthony C Harwood, Sean Z J Lim, T V Raziman, Yan Li, Joseph Stones, John W G Tisch, Simon A R Horsley, Stefano Vezzoli, John B Pendry, Riccardo Sapienza

AI总结 研究通过分析氧化铟锡的带内和带间竞争,揭示了其超快折射率调制机制,发现高驱动能量下非单调振荡行为,为超快光子器件和光学开关的折射率工程提供了直接指导。

Comments 10 pages, 4 figures

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AI中文摘要

在接近介电接近零频率时,透明导电氧化物表现出接近单位的超快折射率调制,推动了时间变化超材料领域的发展,但高驱动能量下的载流子动力学仍不明确。本文报道了氧化铟锡的反射率和透射率的超快调制以及非单调振荡行为。这种现象在通过光学门控技术GRUMPY FROG直接从泵浦-探测光谱图中提取的复费舍尔系数的时间演化中尤为明显。所提取的等离子体频率和阻尼系数的动力学由一个包含竞争非线性带间过程的扩展双温度模型很好地捕捉:在高能量下,热传导电子的阿赫尔型散射促进价带载流子,增加等离子体频率,同时加速热电子冷却并提高阻尼系数。这些结果阐明了氧化铟锡在高驱动能量下的异常动力学起源,并识别出一种可调制的动态行为,对超快折射率工程在时间变化光子器件和光学开关中有直接应用。

英文摘要

Transparent conducting oxides near their epsilon-near-zero frequency exhibit near-unity ultrafast modulations of the refractive index which have enabled the field of time-varying metamaterials, yet the underlying carrier dynamics at high driving fluences remain poorly understood. Here, we report ultrafast modulations in the reflectivity and transmissivity of indium tin oxide, and a non-monotonic oscillatory behavior. This is especially evident in the time evolution of the complex Fresnel coefficients retrieved directly from pump-probe spectrograms using a optical gating technique, GRUMPY FROG. The dynamics of the retrieved plasma frequency and damping coefficient are well captured by an extended two-temperature model incorporating a competing nonlinear interband process: at high fluences, Auger-type scattering of hot conduction electrons promotes valence band carriers, increasing the plasma frequency while accelerating hot-electron cooling and raising the damping coefficient. These results clarify the origin of anomalous high-fluence dynamics in indium tin oxide and identify a fluence-tuneable modulation dynamic with direct implications for ultrafast refractive index engineering in time-varying photonic devices and optical switching

2605.21430 2026-05-21 physics.optics

Holographic EUV Lithography at 40 nm Resolution

40纳米分辨率的全息光刻技术

Ziqi Li, Iason Giannopoulos, Lisong Dong, Dimitrios Kazazis, Xu Ma, Zongqiang Yu, Zhiyuan Niu, Yasin Ekinci, Yayi Wei, Iacopo Mochi

AI总结 本文提出了一种基于全息技术的EUV光刻方法,实现了在13.5纳米波长下进行任意非周期性曲线图案的制备,展示了亚50纳米分辨率、曲线设计自由度和无透镜光学系统的结合,为EUV波长下的纳米结构原型制作提供了独特灵活的工具,并为超越EUV波长的非周期性图案原型制作提供了自然路径。

Comments 20 pages, 5 figures

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AI中文摘要

极紫外(EUV)光刻是制造7纳米节点及更先进集成电路的关键技术,但其依赖多元件反射投影光学使其难以用于小规模研究和原型开发。EUV干涉光刻(EUV-IL)提供了一种无透镜的替代方案,但本质上仅限于周期性结构。本文演示了EUV全息光刻(EUV-HL)作为一种无透镜途径,实现了在13.5纳米波长下任意、非周期性、曲线图案的制备。我们引入了一个逆向设计框架用于计算机生成全息图,该框架在移不变卷积模型中捕捉了EUV掩模衍射的主要物理效应,该模型适用于完整的掩模布局。使用此框架,我们通过直接写入电子束光刻在氢硅氧烷中设计和制造了透射全息掩模,用同步辐射产生的EUV辐射曝光,并以关键尺寸降至40纳米的精度打印目标布局,这比EUV-HL之前的最先进水平提高了近一个数量级。所展示的亚50纳米分辨率、曲线设计自由度和无透镜光学系统的结合,使EUV-HL成为在EUV波长下纳米结构原型制作的独特灵活工具,并为超越EUV(BEUV)波长的非周期性图案原型制作提供了自然路径,而干涉方法目前无法达到。

英文摘要

Extreme ultraviolet (EUV) lithography is the cornerstone of the fabrication of advanced integrated circuits at the 7-nm node and beyond, but its reliance on multi-element reflective projection optics makes it inaccessible for small-scale research and prototyping. EUV interference lithography (EUV-IL) provides a lensless alternative but is intrinsically restricted to periodic structures. Here we demonstrate EUV holographic lithography (EUV-HL) as a lensless route to arbitrary, non-periodic, curvilinear patterning at the EUV wavelength of 13.5 nm. We introduce an inverse-design framework for computer-generated holograms that captures the dominant physical effects of EUV mask diffraction within a shift-invariant convolution model that is tractable for full mask layouts. Using this framework, we design and fabricate transmissive holographic masks by direct-write electron-beam lithography in hydrogen silsesquioxane, expose them with synchrotron-generated EUV radiation, and print target layouts with critical dimensions down to 40 nm, nearly an order of magnitude finer than the previous state of the art in EUV-HL. The demonstrated combination of sub-50 nm resolution, curvilinear design freedom, and a lensless optical setup establishes EUV-HL as a uniquely flexible tool for nanostructure prototyping at EUV wavelengths, and provides a natural pathway to non-periodic pattern prototyping at beyond-EUV (BEUV) wavelengths, which is currently inaccessible to interference-based methods.

2605.21425 2026-05-21 math.NA cs.NA

Achieving Material Robustness via Symmetric Stress Finite Element Discretizations

通过对称应力有限元离散化实现材料鲁棒性

Pablo Brubeck, Charles Parker, Umberto Zerbinati

AI总结 本文研究了在连续力学变分问题中对称应力张量的离散化方法,指出强对称性和弱对称性对数值方案的精度有显著影响,并提出了一种统一理论来解释材料鲁棒性。

Comments 43 pages, 8 figures

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AI中文摘要

在连续力学变分问题中对称应力张量的离散化过程中,必须决定如何强制应力张量的对称性:(i) 通过要求离散张量在每个点上对称,或者 (ii) 通过引入拉格朗日乘数进行弱化。对于Hellinger-Reissner弹性力学和不可压缩流体的速度-应力格式,其中Cauchy应力张量的对称性与角动量守恒相关,我们表明这一选择可能显著影响数值方案的精度。通过一系列具有各向异性本构定律的基准问题,受纤维增强材料、液晶聚合物网络和极性流体启发,我们表明强制弱对称性的方案可以产生任意差的应力近似——即使在零应力配置下。然而,强制强对称性的方案能够独立于本构定律提供准确的应力近似,这一特性我们称为材料鲁棒性。我们提出了一种统一理论,严格解释了这种行为。

英文摘要

When discretizing symmetric stress tensors in variational problems arising in continuum mechanics, one has to choose how to enforce the symmetry of the stress tensor: (i) strongly by requiring the discrete tensors to be pointwise symmetric or (ii) weakly by introducing a Lagrange multiplier. For $H(\mathrm{div})$-conforming finite element discretizations of Hellinger--Reissner elasticity and velocity--stress formulations of incompressible flow, where symmetry of the Cauchy stress tensor is tied to the conservation of angular momentum, we show that this choice may substantially impact the accuracy of the numerical scheme. Through a series of benchmark problems featuring anisotropic constitutive laws inspired by fiber reinforced material, liquid crystal polymer networks, and polar fluids, we show that schemes enforcing symmetry weakly can yield arbitrarily poor stress approximations -- even for zero-stress configurations. However, schemes enforcing symmetry strongly deliver accurate stress approximations independently of the constitutive law, a property we term material robustness. We present a unifying theory that rigorously explains this behavior.

2605.21424 2026-05-21 math.PR

A dice game, a multinomial walk, and the inverted Dirichlet distribution

骰子游戏、多项式漫步与反向Dirichlet分布

Gunther Leobacher, Alexander Steinicke

AI总结 本文通过研究一个简单的骰子游戏,探讨了多项式漫步的有趣性质,利用Gamma与泊松分布、负多项式与反向Dirichlet分布之间的共轭关系,分析了游戏的胜负概率,并展示了正则化Beta函数的单调性及其对游戏胜负概率的影响,还研究了游戏参数趋于无穷时的渐进行为以及游戏最后获胜的概率。

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AI中文摘要

我们考虑一个简单的骰子游戏,这导致了对多项式漫步的引人入胜的研究,具有出人意料且似乎矛盾的性质。通过Gamma与泊松分布、以及负多项式与反向Dirichlet分布之间的共轭关系,研究了一般版本游戏的胜负概率。我们展示了正则化Beta函数的单调性性质,这表明了胜负概率的单调性。此外,分析了游戏在其中一个或几个参数趋于无穷时的渐进行为,以及游戏最后获胜的概率。

英文摘要

We consider a simple dice game, which leads to an intriguing study of multinomial walks, with surprising and seemingly paradoxical properties. The winning and losing probabilities of a general version of the game are investigated via conjugacy relations between Gamma and Poisson distributions, as well as between negative multinomial and inverted Dirichlet distributions. We show a monotonicity property of the regularized beta function, which implies a monotonicity property of the winning probability. Furthermore, the asymptotic behavior of the game for one or several parameters of the game tending to infinity is analyzed, as well as the probability of being last in the game.

2605.21423 2026-05-21 cond-mat.dis-nn cond-mat.mes-hall

Temperature-induced optical enhancement near a localization transition

温度诱导的近局域化转变处的光学增强

Raul Liquito, Miguel Gonçalves, Bruno Amorim, Eduardo V. Castro

AI总结 研究探讨了在准周期系统近局域化转变处温度对有限频率光学电导的影响,发现特定共振频率下低温下的光学电导显著增强,源于Pauli阻塞跃迁的热激活机制。

Comments 19 pages, 12 figures

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AI中文摘要

准周期系统是介于周期晶体和无序系统之间的中间类系统,著名地在二维中表现出金属-绝缘体转变(MIT)。尽管其输运性质已广泛研究,但对临界点附近有限频率光学电导的系统分析仍缺乏。在本工作中,我们对典范的 Aubry-André 模型进行了详细研究。我们发现零温度低频光学信号受到准周期势的强烈重构,表现出在接近 MIT 时连续关闭的光学间隙。最引人注目的是,我们发现在某些共振频率下,低温下的有限频率光学电导出现显著增强。这种增强源于 Pauli 阻塞跃迁在强共振 van Hove 奇点之间的热激活。该机制为准周期系统中有限频率输运提供了新的见解,并为在局域化转变附近操控光学性质提供了新路径。此外,我们的发现确立了光学响应作为一种强大且实验可访问的工具,用于探测非平凡的准周期性效应。

英文摘要

Quasiperiodic systems are an intermediate class of systems between periodic crystals and disordered systems, famously exhibiting metal-insulator transitions (MITs) even in one dimension. While their transport properties have been studied extensively, a systematic analysis of the finite-frequency optical conductivity near the critical point has been lacking. In this work, we carry out a detailed study of the optical conductivity in the paradigmatic Aubry-André model. We find that the zero-temperature low-frequency optical signal is strongly restructured by the quasiperiodic potential, exhibiting an optical gap that closes discontinuously as the system approaches the MIT. Most strikingly, we uncover a mechanism for a strong enhancement of the low-frequency finite temperature optical conductivity at certain resonant frequencies. This enhancement stems from the thermal activation of Pauli-blocked transitions between strongly resonant van Hove singularities. This mechanism provides new insight into finite-frequency transport in quasiperiodic systems and a new pathway for manipulating optical properties near a localization transition. Furthermore, our findings establish the optical response as a powerful, experimentally accessible tool for probing non-trivial quasiperiodicity effects.

2605.21419 2026-05-21 hep-ph astro-ph.CO gr-qc hep-th

Cosmological Collider Signatures from Right-Handed Neutrino Loop

从右旋中微子环看宇宙学碰撞特征

Jingtao You, Linghao Song, Chengcheng Han, Hong-Jian He, Xingang Chen, Zhong-Zhi Xianyu

AI总结 研究通过右旋中微子环在膨胀与中微子锯齿机制结合下的宇宙学碰撞特征,提出一种维度为5的算符,诱导出慢滚背景中的有效化学位移,增强碰撞特征,并展示重右旋中微子可能在原始非高斯性中留下可观测印记。

Comments 73 pages

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AI中文摘要

我们研究了在膨胀与中微子锯齿机制结合下,由右旋中微子环产生的宇宙学碰撞(CC)特征。我们通过一个独特的维度为5的算符来建立inflaton与右旋中微子的相互作用,该算符尊重位移对称性,从而在慢滚背景中诱导出有效的化学位移,导致右旋中微子的偏振依赖性产生,并增强CC特征。右旋中微子由双组分韦伊尔费尔子描述,具有马约拉纳质量项。利用施维纳-凯尔迪什(SK)形式主义,我们推导出一组用于右旋马约拉纳中微子费尔子传播子的种子积分。利用这些积分,我们计算了由右旋中微子三角环产生的三阶inflaton相关子的非本地贡献。我们展示化学位移可以显著削弱重质量玻尔兹曼抑制,并放大与主导偏振模式相关的振荡非高斯性特征。这些结果为分析宇宙学碰撞物理中的费尔子环特征提供了系统框架,并证明与锯齿机制相关的重右旋中微子可能在原始非高斯性中留下可观测印记。

英文摘要

We study cosmological collider (CC) signatures generated by right-handed neutrino loops in the setup of inflation combined with neutrino seesaw mechanism. We formulate the inflaton interaction with the right-handed neutrino through a unique dimension-5 operator respecting shift symmetry, which induces an effective chemical potential in the slow-roll background, leading to helicity-dependent right-handed-neutrino production and enhancing the CC signatures. The right-handed neutrino is described by two-component Weyl spinor with Majorana mass term. Using the Schwinger-Keldysh (SK) formalism, we derive a set of seed integrals for fermion propagators of the right-handed Majorana neutrino. With these we compute the factorized nonlocal contributions to the three-point inflaton correlator generated by the right-handed-neutrino triangle loop. We show that the chemical potential can substantially soften the heavy-mass Boltzmann suppression and amplify the oscillatory non-Gaussianity signatures associated with the dominant helicity mode. These provide a systematic framework for analyzing the fermion loop signatures in the cosmological collider physics and demonstrate that the heavy right-handed neutrinos associated with seesaw mechanism may leave observable imprints in the primordial non-Gaussianities.

2605.21416 2026-05-21 math.ST stat.ME stat.TH

Data driven extreme value distribution estimation: Derivation of the Mean Integrated Squared Error, optimal bandwidth selection and stability conditions

数据驱动的极值分布估计:均方误差的推导、最优带宽选择和稳定性条件

Michael Sandbichler, Tobias Hell

AI总结 本文提出了一种数据驱动的极值分布估计器,推导了其均方误差,用于计算最优带宽并建立了带宽优化过程的稳定性条件。

Comments 37 pages, 5 figures

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AI中文摘要

我们介绍了一种数据驱动的极值分布(DDEVD)估计器,一种基于核的方法,用于从数据中估计极值分布。我们详细推导了其均方误差(MISE),利用它来计算最优带宽,并建立了带宽优化过程的稳定性条件。

英文摘要

We introduce the data driven extreme value distribution (DDEVD) estimator, a kernel-based method for estimating extreme value distributions from data. We derive its mean integrated squared error (MISE) in detail, use it to compute the optimal bandwidth and establish stability conditions for the bandwidth optimization procedure.

2605.21415 2026-05-21 cond-mat.mtrl-sci

Phonon Interactions in Metal Halide Perovskites elucidated by Raman Scattering

金属卤化物钙钛矿中的声子相互作用通过拉曼散射得到阐明

Alejandro R. Goñi

AI总结 本文通过拉曼散射研究金属卤化物钙钛矿中声子相互作用的机制,探讨了声子频率、线宽和寿命受晶格势非谐性及静态/动态无序的影响,并解释了强拉曼背景信号的起源。

Comments 29 pages, 6 figures

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AI中文摘要

目前普遍认为金属卤化物钙钛矿(MHPs)的优异光电性质主要归因于无机笼状晶格与A位阳离子亚晶格之间的独特相互作用。这种相互作用显著影响MHPs的振动光谱(声子频率、线宽和寿命),这是由于晶格势非谐性和/或静态/动态无序的影响。拉曼散射是一种探测固体中声子相互作用的合适技术,允许对化学环境进行原位表征,揭示晶格振动的性质。在本文中,将回顾现有的实验证据,特别强调理解拉曼特征,取决于耦合主要由氢键或立体阻碍介导。关于强拉曼背景信号的起源的争议将被特别讨论。该背景信号通常在立方相和四方相稳定温度范围内观察到,当A位阳离子动态展开时,该信号主要是由于无序诱导的二级声子拉曼散射。这一解释在其他具有纳米级结构无序的半导体系统中得到支持,其中中心拉曼峰要么来自多层异质结构中Ge量子点的垂直错位,要么来自短周期GaAs/AlAs超晶格的界面粗糙度。通过这种方式,提供了MHPs中声子相互作用的统一图景以及它们如何影响不同拉曼过程,这对于解释其拉曼光谱至关重要。

英文摘要

There is a growing consensus that the exceptional optoelectronic properties of metal halide perovskites (MHPs) are largely due to the peculiar interplay between the inorganic cage lattice, composed of a labile network of corner-sharing metal halide octahedra, and the A-site cationic sublattice. This interaction significantly affects the vibrational spectrum of MHPs (phonon frequencies, linewidths, and lifetimes), resulting from the effects of lattice potential anharmonicity and/or static/dynamic disorder. Raman scattering is a suitable technique to probe phonon interactions in solids, allowing for the in-situ characterization of chemical environments, revealing the nature of lattice vibrations. In this perspective, the available experimental evidence of the aforementioned interplay will be reviewed with special emphasis on understanding Raman signatures depending on whether the coupling is principally mediated by hydrogen bonding or steric hindrance. The controversy about the origin of a strong Raman background, steeply rising towards zero Raman shift and called central peak, will be specifically addressed. This background signal, which is typically observed in the temperature range of stability of cubic and tetragonal phases when the A-site cation dynamics unfold, will be shown to be mostly due to disorder-induced second-order acoustic-phonon Raman scattering. This interpretation receives support from other semiconductor systems with nanoscale structural disorder, where the central Raman peak arises either from the vertical misalignment of Ge quantum dots in multi-stack heterostructures or from the interface roughness exhibited by short-period GaAs/AlAs superlattices. In this way, a unifying picture of phonon interactions in MHPs and how they impact different Raman processes is provided, which is key to interpreting their Raman spectra.

2605.21410 2026-05-21 math.SG math.DG

A Serre type vanishing property of the twisted primitive cohomology

辛 manifold 的 twisted primitive cohomology 的 Serre 类消失性质

Hao Zhuang

AI总结 本文证明了辛 manifold 的 twisted primitive cohomology 的 Serre 类消失性质,基于 Tseng 和 Zhou 的 symplectic flatness 下的消失性质,强调了在将复几何中 sheaf cohomology 的某些结果推广到辛几何中 primitive cohomology 时 symplectic flatness 的必要性。

Comments 6 pages. Comments are welcome

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AI中文摘要

我们证明了辛 manifold 的 twisted primitive cohomology 的 Serre 类消失性质。它基于 Tseng 和 Zhou 在 symplectic flatness 下的消失性质。这些消失性质强调了在将复几何中 sheaf cohomology 的某些结果推广到辛几何中 primitive cohomology 时 symplectic flatness 的必要性。

英文摘要

We prove a Serre type vanishing property for the twisted primitive cohomology of a symplectic manifold. It is based on Tseng and Zhou's vanishing property under the symplectic flatness. These vanishing properties emphasizes the necessity of the symplectic flatness when generalizing certain results from the sheaf cohomology in complex geometry to the primitive cohomology in symplectic geometry.

2605.21409 2026-05-21 q-fin.PM q-fin.CP

Portfolio Preference Elicitation in Institutional Crossing Markets

机构交叉市场中的投资偏好挖掘

Yoontae Hwang

AI总结 本文研究了机构交叉市场中如何通过有限信息获取投资偏好,提出了一种混合查询方法,通过需求查询和价值查询相结合,提高了流动性发现的效率,并验证了在不同通信预算下混合方法在恢复福利方面的有效性。

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AI中文摘要

机构交叉平台面临一个信息隐藏问题:投资者将交易视为投资组合,但流动性发现通常围绕个别证券进行。我们模型将投资组合交叉视为有限通信下的偏好挖掘过程,平台首先使用价格导向的需求查询搜索投资组合空间,然后通过价值查询验证选定的包; incumbent验证查询记录在进一步探索前发现的需求分配。最终的分配来自挖掘报告,因此学习模型指导查询但不决定福利。分析显示了搜索和验证的互补性。需求查询定位非分离投资组合空间中的高价值区域,但除非验证选定的包,否则只能提供保守的福利证据。价值查询提供精确的福利比较,但当应用于目标不佳的包时效果不佳。使用美国、韩国、日本和德国的股权面板进行市场校准实验,结果显示仅需求或仅价值的设计在有限查询预算下只能恢复约全部信息福利的一半,而混合程序在通信扩展时可恢复88%并接近95%。我们还比较了精确证券级包与因子完成的篮子包在同一分配规则下的表现。证券级包是当精确证券披露成本低时的无调整效率模式。因子完成的篮子包在预交易信息传递成本高时更受欢迎。结果将投资组合交叉描述为一个选择性验证问题,并识别披露敏感的包表示作为隐藏流动性平台的核心设计选择。

英文摘要

Institutional crossing platforms face a hidden-information problem: investors value trades as portfolios, but liquidity discovery is typically organized around individual securities. We model portfolio crossing as limited-communication preference elicitation over signed portfolio trades. The platform first uses price-directed demand queries to search the portfolio space and then verifies selected packages through value queries; an incumbent verification query records the demand-discovered allocation before further exploration. Final allocations are chosen from elicited reports, so the learning model guides queries but does not determine welfare. The analysis shows why search and verification are complementary. Demand queries locate high-value regions of a nonseparable portfolio space, but they provide only conservative welfare evidence unless selected packages are verified. Value queries provide exact welfare comparisons, but they are ineffective when applied to poorly targeted packages. Market-calibrated experiments using equity panels from the United States, Korea, Japan, and Germany show that demand-only and value-only designs recover only about half of full-information welfare under a limited query budget, whereas the hybrid procedure recovers 88\% and approaches 95\% as communication expands. We then compare exact security-level packages with factor-completed basket packages within the same allocation rule. Security-level packages are the unadjusted-efficiency mode when exact-securities disclosure is inexpensive. Factor-completed baskets become preferable when pretrade message informativeness is costly. The results characterize portfolio crossing as a selective verification problem and identify disclosure-sensitive package representation as a core design choice for hidden liquidity platforms.

2605.21408 2026-05-21 stat.ME

TCARD: Nearly Balanced Two-Level Designs with Treatment Cardinality Constraints with an Application to LLM Prompt Engineering

TCARD: 近似平衡的双水平设计与处理基数约束及其在大语言模型提示工程中的应用

Kexin Xie, Ryan Lekivetz, Xinwei Deng

AI总结 本文研究了在处理基数约束下近似平衡的双水平设计,提出了一种新的无模型目标函数,用于优化设计的平衡性和均匀性,并通过数值实验验证了其在不同问题规模和约束强度下的有效性。

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AI中文摘要

现代实验设计常常面临所谓的处理基数约束,即每个处理中包含的因素数量的限制。在工程模拟、人工智能系统调优和大规模系统验证中,这种约束非常常见。这需要开发适当的设计以在可行约束下实现统计效率。本文研究了在该k-处理基数约束(TCARD)下的双水平设计,其中设计矩阵X∈{0,1}^{n×p}具有恒定的行和等于k。尽管TCARD与平衡不完全块设计(BIBD)密切相关,但许多实际(n,p,k)组合无法获得精确的BIBD结构。这导致了近似平衡TCARD的概念,我们证明了它们最小化广义字长模式的第一两个组件。我们还显示,在这种情况下良好的投影行为由两种基于计数的规律控制:平衡因素重复和均匀的成对共现。受此表征的启发,我们提出了一种无模型目标函数,即平衡共现偏差(Φ_BCD),它联合惩罚重复不平衡和共现分散。我们进一步表明,这一准则与经典最优原则密切相关,包括(M,S)-最优性、中心UE(s²)准则和贝叶斯D-最优性。为了构造最小化Φ_BCD的设计,我们开发了一种坐标交换(CE)算法,具有高效的增量更新,以及基于模拟的程序用于校准准则权重以适应预期的下游任务。数值实验确认,所提出的方法在不同问题规模和约束强度下均优于现有替代方法。

英文摘要

Modern experimental designs often face the so-called treatment cardinality constraint, which is the constraint on the number of included factors in each treatment. Experiments with such constraints are commonly encountered in engineering simulation, AI system tuning, and large-scale system verification. This calls for the development of adequate designs to enable statistical efficiency for modeling and analysis within feasible constraints. In this work, we study two-level designs under this $k$-treatment cardinality constraint (TCARD), where the design matrix $\mathbf{X} \in \{0,1\}^{n \times p}$ has constant row sums equal to $k$. Although TCARDs are closely related to balanced incomplete block designs (BIBDs), exact BIBD structure is unavailable for many practical $(n,p,k)$ combinations. This leads to the notion of nearly balanced TCARDs, which we prove minimize the first two components of the generalized word-length pattern. We also show that good projection behavior in this setting is governed by two count-based regularities: balanced factor replications and uniform pairwise concurrences. Motivated by this characterization, we then propose the Balanced Concurrence Deviation ($Φ_{\mathrm{BCD}}$), a model-free objective that jointly penalizes replication imbalance and concurrence dispersion. We further show that this criterion is closely connected to classical optimality principles, including $(M,S)$-optimality, centered $\mathrm{UE}(s^2)$ criterion, and Bayesian $D$-optimality. To construct designs minimizing $Φ_{\mathrm{BCD}}$, we develop a coordinate-exchange (CE) algorithm with efficient incremental updates, together with a simulation-based procedure for calibrating the criterion weights to the intended downstream task. Numerical experiments confirm that the proposed method compares favorably with existing alternatives across a range of problem sizes and constraint strengths.

2605.21407 2026-05-21 astro-ph.SR astro-ph.EP

Lithium Enrichment in a Subgiant Star with a Brown Dwarf Companion: A Planetary Engulfment Candidate

亚巨星星中伴有一颗褐矮星的锂富集:一个行星吞噬候选体

Brooke Kotten, Melinda Soares-Furtado, Ricardo Yarza, Andrew C. Nine, Seth A. Jacobson, Noah Vowell, Olivia Maynard, Allyson Bieryla, Andrew Vanderburg, Jack Schulte, Claudia Aguilera-Gomez, Enrico Ramirez-Ruiz, Joseph E. Rodriguez, David W. Latham

AI总结 研究通过分析亚巨星TOI-5882的锂含量,验证了行星吞噬理论,发现其锂富集可能源于吞噬了一颗超级地球至海王星质量的行星。

Comments 21 pages, 6 figures, 2 tables. Accepted to The Astrophysical Journal

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AI中文摘要

理论模型预测,在狭窄质量范围内存在的亚巨星可以保留可检测的行星吞噬引起的锂富集特征。我们通过TOI-5882进行测试,该星体处于有利的亚巨星参数空间,并拥有一颗质量大的褐矮星伴星(22 M_J,周期7.1天),能够动态扰动内行星。我们调查了以下问题:(1)TOI-5882是否在相似的亚巨星中表现出锂增强;(2)行星物质是否会被沉积到对流层;(3)所需的吞噬质量是否在合理的行星吞噬范围内。利用Tillinghast反射镜光谱仪的光谱数据,我们测得Li I等效宽度为75.39±3.58 mA,以及A(Li)=2.49±0.12 dex。将这些值与来自GALactic Archaeology with HERMES (GALAH) DR4调查的61个亚巨星对照样本相比,发现TOI-5882在两个指标中均处于第98.4百分位,证实了显著的锂富集。我们通过建模对流层沉积和估计相对于对照样本所需的吞噬质量来评估吞噬情景。我们进行了吞噬行星质量的估计,考虑CI碳质球粒陨石的锂丰度,因为通过核心吸积形成的行星富含重元素,锂与这些金属结合。这导致所需的吞噬质量为9-95 M_⊕--比由原太阳假设所暗示的5.6 M_J小一个数量级。TOI-5882的锂过剩可能源于吞噬了一颗超级地球至海王星质量的行星,这促使进一步研究以测试这一情景。

英文摘要

Theoretical models predict that subgiants within a narrow mass regime can retain detectable lithium enrichment signatures from planetary engulfment. We test this prediction using TOI-5882, selected because it occupies this favorable subgiant parameter space and hosts a massive brown dwarf ($22 \, M_{ \rm J}$, $P=7.1 \,{\rm d}$) companion capable of dynamically perturbing inner planets. We investigate whether: (1) TOI-5882 exhibits lithium enhancement among similar subgiants, (2) planetary material would be deposited in the convective zone, and (3) the required engulfed mass lies within a plausible range for planetary engulfment. Using spectra from the Tillinghast Reflector Echelle Spectrograph, we measured a Li I equivalent width of $75.39 \pm 3.58$ mA and an abundance of A(Li) $=2.49 \pm 0.12$ dex. Comparing these values to a control sample of 61 subgiants from the GALactic Archaeology with HERMES (GALAH) DR4 survey, we find that TOI-5882 ranks in the 98.4th percentile in both metrics, confirming significant lithium enrichment. We evaluate the engulfment scenario by modeling convective zone deposition and estimating the mass required to reproduce the observed enhancement relative to the control sample. We perform an estimate of the engulfed planetary mass incorporating CI chondritic Li abundances, as planets formed via core accretion are enriched in heavy elements and lithium partitions with these metals. This yields a required engulfed mass of $9$-$95\,M_\oplus$--an order of magnitude lower than the $5.6 \, M_{\rm J}$ implied by proto-solar assumptions. TOI-5882's lithium excess can plausibly result from the ingestion of a super-Earth to Neptune-mass planet, motivating further studies to test this scenario.

2605.21399 2026-05-21 eess.SY cs.SY

Output Feedback Control of Linear Time-Invariant Systems with Operational Constraints

线性时不变系统输出反馈控制与操作约束

Marcel Menner, Heather Hussain, Eugene Lavretsky

AI总结 本文提出了一种系统的方法,用于在存在操作约束的情况下设计鲁棒线性控制器,利用Nagumo定理和比较引理保证约束满足,同时结合受控屏障函数启发的最小范数最优控制原理,设计出连续分段线性输出反馈控制器,保持闭环系统分析的可线性化。通过飞行控制贸易研究,展示了该框架在安全关键航空器控制中的实际相关性。

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AI中文摘要

本文介绍了一种系统的方法,用于在存在操作约束的情况下设计鲁棒线性控制器。该设计利用Nagumo定理和比较引理来保证约束满足,同时结合受控屏障函数启发的最小范数最优控制原理。所得到的控制器是一种连续分段线性输出反馈策略,保持闭环系统使用线性系统理论分析的可分析性。由于线性控制设计,多输入多输出(MIMO)鲁棒裕度可以在有无主动操作约束的情况下推导出来。本文表明,可以通过基于观测器的输出反馈控制设计满足系统状态的操作约束。通过飞行控制贸易研究,我们展示了该框架在安全关键航空器控制中的实际相关性。

英文摘要

This paper introduces a systematic method for designing robust linear controllers using output feedback in the presence of operational constraints. The design uses Nagumo's Theorem and the Comparison Lemma to guarantee constraint satisfaction, while incorporating min-norm optimal control principles inspired by Control Barrier Functions. The resulting controller is a continuous piecewise-linear output feedback policy that preserves the closed-loop system's analyzability using linear systems theory. Due to the linear control design, multi-input multi-output (MIMO) robustness margins can be derived with and without active operational constraints. This paper shows that operational constraints on the system's state can be satisfied using an observer-based output feedback control design. Through flight control trade studies, we demonstrate the practical relevance of the framework in safety-critical aircraft control applications.

2605.21396 2026-05-21 eess.SY cs.SY

Grid-Aware Peer-to-Peer Energy Trading: A Learning-Augmented Framework

考虑网格的点对点能源交易:一种学习增强的框架

Devangi, Ankit Singhal, Yashasvi Bansal

AI总结 本文提出了一种学习增强的点对点能源交易和电网运营商接口,通过监督变压器回归模型使微电网能够本地预测电网运营商的响应,从而减少交易开销,减轻电网运营商负担并保护信息隐私。

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AI中文摘要

配电网络由于分布式能源资源(DERs)的日益整合而从被动系统向主动系统转变。点对点(P2P)能源交易作为一种可行的框架,使参与者之间能够进行本地能源交换,此处表示为聚合微电网(MGs)。将网络约束纳入其中对于确保P2P交易在物理上可行且符合电网运行限制至关重要。然而,现有的P2P框架仍然缺乏先进的预测机制,使生产者消费者(prosumers)在交易制定过程中无法预知网络可行性或电网运营商(DSO)的响应。本文提出了一种学习增强的P2P和DSO接口,该接口预测DSO对所提出的P2P交易的响应,使生产者消费者能够自我评估并改进其交易决策。一个监督变压器基于回归模型被训练以使MGs能够本地预测DSO的响应而无需共享其提出的交易,从而减少交易开销,减轻DSO负担并保护信息隐私。所提出的框架在修改后的IEEE 33 bus配电电力系统上进行了验证,该系统包含互联微电网。通过案例研究验证了所提模型在市场效率、交易接受度和计算负担方面的有效性。

英文摘要

Distribution networks are transitioning from passive to active systems due to the growing integration of distributed energy resources (DERs). Peer to Peer (P2P) energy trading has emerged as a viable framework that enables local energy exchange among participants, represented here as aggregated microgrids (MGs). Incorporating network constraints is essential to ensure that P2P transactions remain physically feasible and consistent with grid's operating limits. However, existing P2P frameworks still lack advanced predictive mechanisms that allow prosumers to anticipate network feasibility or the distribution system operator (DSO) response during trade formulation. This paper proposes a learning augmented P2P and DSO interface that predicts the DSOs response to the proposed P2P trades, allowing prosumers to self-assess and refine their trading decisions. A supervised transformer based regression model is trained to enable MGs to locally predict the DSOs response without sharing their proposed trades, thereby reducing transaction overhead, alleviating DSO burden, and preserving information privacy. The proposed framework is validated on the modified IEEE 33 bus distribution power system with interconnected microgrids. Case studies are presented to validate the effectiveness of the proposed model in terms of market efficiency, trade acceptance and computational burden.

2605.21394 2026-05-21 math.AP

Similarity Solutions for the Flux limited Keller Segel System with Time Varying Chemical Decay Rate

针对具有时间变化化学衰减率的有限流凯勒-塞格尔系统的相似解

Ahmed Abbas Jaber Al Furaiji, Ghorbanali Haghighatdoost, Mustafa Bazghandi

AI总结 本文研究了一个一维有限流凯勒-塞格尔系统(FLKS),其中化学衰减率可以显式地随时间变化,这一特性受到酶促调节和化学趋化信号环境变化的启发。通过将衰减率视为任意函数,系统地进行了偏微分方程系统的对称性分析,并利用等价变换进行完整的群分类,识别了任意衰减函数允许的对称性代数,并确定了三种区分情况,扩展了常数衰减率、反时间(幂律)衰减和指数衰减的对称性代数。对于每种情况,构建了子代数的最优系统并推导了相应的相似约简。最后,我们为FLKS模型找到了一些显式解。我们的结果为理解哪些时间衰减模式允许相似约简提供了严谨的数学基础,从而促进了具有现实时间变化降解机制的有限流趋化模型的分析进展。

Comments 22, 4

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AI中文摘要

我们研究了一个一维有限流凯勒-塞格尔系统(FLKS),其中化学衰减率被允许显式地随时间变化,这一特性受到酶促调节和化学趋化信号环境变化的启发。将衰减率视为任意函数,我们对由此得到的PDE系统进行了系统性的对称性分析,并利用等价变换进行完整的群分类,我们识别了任意衰减函数允许的对称性代数,并确定了三种区分情况,扩展了常数衰减率、反时间(幂律)衰减和指数衰减的对称性代数。对于每种情况,我们构建了子代数的最优系统并推导了相应的相似约简。最后,我们为FLKS模型找到了一些显式解。我们的结果为理解哪些时间衰减模式允许相似约简提供了严谨的数学基础,从而促进了具有现实时间变化降解机制的有限流趋化模型的分析进展。

英文摘要

We investigate a one dimensional flux limited Keller Segel system (FLKS) in which the chemical decay rate is allowed to vary explicitly in time, a feature motivated by enzymatic regulation and environmental variability in chemotactic signalling. Treating the decay rate as an arbitrary function, we carry out a systematic Lie symmetry analysis of the resulting PDE system and employ equivalence transformations to perform a complete group classification, we identify the kernel symmetry algebra admitted for arbitrary decay functions and determine three distinguished cases that extend the symmetry algebra constant decay rates, inverse time (power law) decay, and exponential decay. For each case, we construct an optimal system of subalgebras and derive the corresponding similarity reductions. Finally, we find some explicit solutions for our FLKS model. Our results provide a rigorous mathematical foundation for understanding which temporal decay patterns admit similarity reductions, thereby enabling analytical progress on flux limited chemotaxis models with realistic time varying degradation mechanisms.

2605.21393 2026-05-21 gr-qc

Versal transition scenarios in inflationary cosmology: slow roll, ultra-slow roll, and oscillatory exit

inflationary cosmology中的Versal过渡场景:慢-roll,超慢-roll和振荡退出

Spiros Cotsakis

AI总结 本文提出了一种面向物理的持久性/过渡多样性框架,用于标量场宇宙学,特别针对膨胀动力学。该框架认为,观测上可行的膨胀模型通常最好被理解为由持久阶段串联而成,这些阶段由普遍的过渡事件分隔。慢roll表现为稳定的持久平衡,超慢roll表现为接近非双曲组织集的瓶颈通过,而振荡后期行为则表现为重复的退出部分。通过指数模型作为参考制度图谱和质量案例作为斜率漂移的动力学实现,展示了这些历史如何被组织和读取几何学。所得到的框架明确指出,相关的制度过渡精确发生在双曲性丧失或谱跨过虚轴的地方,因此无法被纯粹双曲或渐近处理所看到。

Comments 27 pages, 1 figure

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AI中文摘要

我们开发了一种面向物理的持久性/过渡多样性框架的版本,用于标量场宇宙学,专门针对膨胀动力学。核心思想是,观测上可行的膨胀模型通常最好被理解为由持久阶段串联而成,而不是单一渐近阶段。在这一图景中,慢roll表现为稳健的持久平衡,超慢roll表现为接近非双曲组织集的瓶颈通过,而振荡后期行为则表现为重复的退出部分。通过指数模型作为参考制度图谱和质量案例作为斜率漂移的动力学实现,我们展示了这些历史如何被组织和读取几何学。所得到的框架明确指出,相关的制度过渡精确发生在双曲性丧失或谱跨过虚轴的地方,因此无法被纯粹双曲或渐近处理所看到。

英文摘要

We develop a physics-facing version of the persistence/transition-variety framework for scalar-field cosmology, tailored to inflationary dynamics. The guiding idea is that observationally viable inflationary models are often best understood not as single asymptotic phases but as concatenations of persistent regimes separated by universal transition episodes. In this picture, slow roll appears as a robust persistent balance, ultra-slow roll as a bottleneck passage near a nonhyperbolic organising set, and oscillatory post-inflationary behaviour as a recurrent exit sector. Using the exponential model as a reference regime atlas and the massive case as a dynamical realisation of slope drift, we show how such histories may be organised and read geometrically. The resulting framework makes explicit that the relevant regime transitions are organised precisely where hyperbolicity is lost or the spectrum crosses the imaginary axis, and are therefore invisible to a purely hyperbolic or asymptotic treatment.

2605.21392 2026-05-21 cs.CR

VIPER-MCP: Detecting and Exploiting Taint-Style Vulnerabilities in Model Context Protocol Servers

VIPER-MCP: 检测和利用模型上下文协议服务器中的污点式漏洞

Pengyu Sun, Qishu Jin, Enhao Huang, Zifeng Kang, Xin Liu, Dakun Shen, Song Li

AI总结 本文提出VIPER-MCP,一种用于模型上下文协议服务器的端到端自动漏洞审计框架,能够检测污点式漏洞并动态验证其可利用性,通过生成具体的概念验证提示。该框架引入了两种新技术:一种是双阶段静态分析策略中的锚查询,增强了标准污点警报的功能性上下文;另一种是反馈驱动的提示进化机制,通过双变异调度和适应度评分的种子选择,逐步优化自然语言提示以达到易受攻击的sink。

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AI中文摘要

模型上下文协议(MCP)已成为连接LLM代理到外部工具的标准接口。由于MCP服务器将诸如shell执行、网络访问和文件系统操作等特权操作暴露给由代理驱动的调用,工具处理程序的实现缺陷可能导致从自然语言输入直接到达安全敏感的sink,从而可能授予攻击者远程代码执行或完整系统控制。现有方法要么产生未经验证的静态警报,要么依赖于固定的模板库,缺乏代码层面的指导,并无法触发需要特定参数形状或多步骤污点路径的漏洞。在本文中,我们提出了VIPER-MCP,这是首个针对MCP服务器的端到端自动漏洞审计框架,不仅能够检测污点式漏洞,还能通过生成具体的概念验证提示动态验证其可利用性。VIPER-MCP引入了两种新技术:(1)一种双阶段静态分析策略中的锚查询,增强了标准污点警报的功能性上下文,将文件级静态特征解析为特定的MCP工具处理程序,并生成漏洞锚定的调用链;(2)一种反馈驱动的提示进化机制,通过双变异调度独立纠正工具选择漂移并加深参数渗透,结合适应度评分的种子选择,逐步优化自然语言提示以达到易受攻击的sink。在对39,884个真实世界的开源MCP服务器仓库进行大规模扫描中,VIPER-MCP发现了106个零日漏洞,所有均通过端到端的利用跟踪得到确认,目前已有67个CVE ID被分配。我们已负责任地向受影响的开发者披露所有确认的发现,并协调CVE分配。

英文摘要

Model Context Protocol (MCP) has emerged as a standard interface for connecting LLM agents to external tools. Because MCP servers expose privileged operations such as shell execution, network access, and file-system manipulation to agent-driven invocation, implementation flaws in tool handlers can create a direct path from natural-language input to security-sensitive sinks, potentially granting attackers remote code execution or full system compromise. Existing approaches either produce unconfirmed static alerts without dynamic validation, or rely on fixed template libraries that lack code-level guidance and fail to trigger vulnerabilities requiring specific parameter shapes or multi-step taint paths. In this paper, we present VIPER-MCP, the first end-to-end automated vulnerability auditing framework for MCP servers that not only detects taint-style vulnerabilities but also dynamically confirms their exploitability by producing concrete proof-of-concept prompts. VIPER-MCP introduces two novel techniques: (1) an anchor-query pass in a two-pass static analysis strategy that augments standard taint alerts with function-level structural context, resolving file-level static artifacts to specific MCP tool handlers and producing vulnerability-anchored call chains; and (2) a feedback-driven prompt evolution mechanism that employs dual-mutator scheduling that independently corrects tool-selection drift and deepens parameter penetration, together with fitness-scored seed selection to iteratively refine natural-language prompts toward vulnerable sinks. In a large-scale scan of 39,884 real-world open-source MCP server repositories, VIPER-MCP discovered 106 0-day vulnerabilities, all of which were confirmed through end-to-end exploit traces, with 67 CVE IDs assigned to date. We responsibly disclosed all confirmed findings to the affected developers and coordinated CVE assignment where applicable.

2605.21389 2026-05-21 cond-mat.mes-hall cond-mat.mtrl-sci

Huge ultrafast spin Seebeck effect mediated by laser-excited superdiffusive magnon currents

由激光激发的超扩散磁子电流介导的巨大超快自旋Seebeck效应

Luca Mikadze, Peter M. Oppeneer, Markus Weißenhofer

AI总结 该研究提出了一种基于量子玻尔兹曼方程的微观框架,用于模拟超快激光诱导去磁化过程,揭示了超扩散磁子传输现象,并预测了技术相关幅度的超快自旋Seebeck效应。

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AI中文摘要

铁磁金属的亚皮秒激光激发诱导了涉及电子、声子和磁子散射和传输的强烈非平衡动力学。广泛使用的理论方法,如三温模型和扩散方程,无法在超快时间尺度上捕捉这些过程。在这里,我们提出了一种基于初值参数化的微观框架,通过量子玻尔兹曼方程纳入非热磁子散射和传输。我们应用这种方法来模拟超快激光诱导去磁化在bcc铁薄膜中的过程。该模型预测了超快自旋Seebeck效应,其特征是强爆发的快速移动磁子自旋电流达到技术相关幅度。此外,我们识别出超扩散传输区域:从最初球形的磁子传输到后来的扩散区域的过渡。为了将我们的理论预测与实验可访问的可观测性连接起来,我们计算了由预测的深度解析磁化分布所产生的磁光 Kerr 角度。我们的框架提供了一种描述超快非热磁子传输的方法,超越了扩散模型,并将有助于时间分辨自旋传输实验的设计和解释。

英文摘要

Subpicosecond laser excitation of ferromagnetic metals induces strongly nonequilibrium dynamics involving scattering and transport of electrons, phonons, and magnons. Widely used theoretical approaches, such as the three-temperature model and diffusion equations, are ill-suited to capture these processes on ultrafast timescales. Here, we present an ab initio-parameterized microscopic framework that incorporates nonthermal magnon scattering and transport via the quantum Boltzmann equation. We apply this approach to simulate ultrafast laser-induced demagnetization in bcc Fe films. The model predicts an ultrafast spin Seebeck effect, characterized by a strong burst of fast-moving magnonic spin current reaching technologically relevant amplitudes. Furthermore, we identify a superdiffusive transport regime: a crossover from initially ballistic magnon transport to a diffusive regime at later times. To connect our theoretical predictions to experimentally accessible observables, we calculate the magneto-optical Kerr angles resulting from the predicted depth-resolved magnetization profiles. Our framework provides a route to describe ultrafast nonthermal magnon transport beyond diffusive models and will aid in the design and interpretation of time-resolved spin-transport experiments.

2605.21387 2026-05-21 stat.ME

Clustering Craters on the Moon with Dysfunctional Families

用功能失调家族方法对月球陨石坑进行聚类

Nathan Weed, Emily Castleton, Dave Osthus, Brian Weaver, Richard L. Warr

AI总结 本文提出了一种新的聚类方法,结合功能失调家族约束到贝叶斯非参数聚类方法中,以解决专家陨石坑识别列表的整合问题,并提供聚类不确定性估计。

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AI中文摘要

对地球天体上的陨石坑数量和大小分布的总结对于理解太阳系的历史至关重要。然而,识别陨石坑却未被自动化,因此依赖专家陨石坑计数员标记静态图像。Robbins等人(2014)(以下简称R14)表明,与之前假设相反,专家陨石坑计数员的识别陨石坑列表之间存在显著差异。如何最佳地结合多个专家的识别陨石坑列表以了解太阳系的历史是一个开放且重要的问题。R14通过修改流行的DBSCAN聚类方法进行聚类。然而,他们的方法并未利用所有可用的约束信息,也未提供聚类不确定性的估计。为了解决DBSCAN方法的不足,我们提出了一种新的聚类方法,可以结合同一图像中多个感兴趣的物体列表。关键创新是将功能失调家族约束纳入贝叶斯非参数聚类方法,即中文餐厅过程(CRP),该方法自然考虑了陨石坑标识信息。功能失调家族中文餐厅过程(DFCRP)提供了聚类不确定性的估计。在本工作中,我们提供了超参数规范的指导,提出了一个吉布斯采样器,并进行了模拟研究,以比较DFCRP与CRP的性能。最后,我们将DFCRP应用于R14的陨石坑识别问题,比较结果,并展示了使用后验抽样聚类分配所进行的分析类型。

英文摘要

Summaries of craters on terrestrial bodies, such as the number and size distribution, are essential for understanding the history of the Solar System. Identifying craters, however, has not been automated and thus relies on expert crater-counters marking static images. Robbins et al. (2014) (hereafter R14) showed that, contrary to previously held assumptions, there exists large variability across expert crater-counters' identified crater lists. How best to combine identified crater lists across multiple experts for the purposes of learning about the Solar System is an open and consequential question. R14 combined identified crater lists via clustering through a modification of the popular DBSCAN clustering method. Their approach did not, however, make use of all the constraining information available nor did it provide an estimate of clustering uncertainty. To address the shortcomings of the DBSCAN method, we present a novel clustering approach that can combine multiple lists of identified objects of interest from the same image. The key innovation is incorporating a dysfunctional family constraint into the Bayesian nonparametric clustering approach, the Chinese restaurant process (CRP), which naturally takes into account information about the crater identifier. The dysfunctional family Chinese restaurant process (DFCRP) provides an estimate of clustering uncertainty. In this work, we provide guidance on hyperparameter specification, present a Gibbs sampler, and perform a simulation study to compare the performance of the DFCRP to the CRP. Finally, we apply the DFCRP to the crater identification problem of R14, comparing results, and also demonstrate the types of analyses that can be performed with posterior draws of cluster assignments.

2605.21386 2026-05-21 cond-mat.str-el

Strange metallicity in the Kagome metal Ni$_3$In: a DMFT investigation

Kagome金属Ni₃In中的奇异金属性:一种DMFT研究

Ruslan Mushkaev, Francesco Petocchi, Philipp Werner

AI总结 该研究通过DMFT方法探讨了Kagome金属Ni₃In中的奇异金属性,发现其电阻率随温度线性变化,并揭示了局部磁矩的形成及重费米液体行为的出现。

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AI中文摘要

奇异金属性,其电阻率随温度线性变化,在广泛的相关材料中被观察到,包括重费米子化合物和铜基超导体。最近,Kagome金属Ni₃In也被报告出现这种现象,其原因在于部分扁平带导致几乎局域化的和它inerant电子自由度共存。我们通过在最小单带Hubbard模型上进行动态平均场理论(DMFT)计算,研究了Ni₃In的相关电子结构和输运性质。尽管带填充较大,即使对于中等Hubbard排斥作用,我们仍观察到自能的非费米液体频率依赖性,以及局部磁矩的形成。随着空穴掺杂的增加,发现向重费米液体行为的过渡。我们将这些结果解释为近似填充的窄带在k_z=0附近的有效模型。

英文摘要

Strange metallicity, characterized by a linear temperature dependence of the resistivity, is observed in a broad range of correlated materials, including heavy-fermion compounds and cuprate superconductors. It has also recently been reported for the Kagome metal Ni$_3$In, where almost localized and itinerant electronic degrees of freedom coexist as a result of a partially flat band. We investigate the correlated electronic structure and transport properties of Ni$_3$In with dynamical mean field theory (DMFT) calculations performed on a minimal single-band Hubbard model, constructed from compact molecular orbitals. Despite the large band filling, even for moderate Hubbard repulsion, we observe a non-Fermi-liquid like frequency dependence of the self-energy, as well as the formation of local magnetic moments. With increased hole doping, a crossover to a heavy Fermi-liquid regime is found. We interpret these results in terms of an effective model for the partially filled narrow band near $k_z=0$.

2605.21383 2026-05-21 astro-ph.EP astro-ph.SR

Producing planetary debris exterior to white dwarf Roche radii through sublimative rotational fission

通过亚limative旋转分裂产生白矮星Roche半径以外的行星碎片

Dimitri Veras, Jordan K. Steckloff, Kathryn Volk

AI总结 研究探讨了通过亚limative出气导致的旋转分裂在白矮星Roche半径外产生行星碎片的条件,比较了SYORP和YORP效应的效率,并指出即使在较短的冷却时间尺度内,水冰出气也能在可观察的时间尺度内产生碎片。

Comments Accepted for publication in MNRAS

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AI中文摘要

大多数宿主周期性 transit 行星碎片的白矮星位于 rubble-pile Roche极限之外,这与传统潮汐破坏小行星的形成模型相矛盾。本文量化了在1-5 Roche半径范围内,由于sublimative出气导致的旋转分裂(

英文摘要

The majority of white dwarfs that host periodic transiting planetary debris do so at distances that exceed the rubble-pile Roche limit, in disagreement with canonical formation models that focus on the tidal disruption of minor planets. Here, we quantify the conditions by which rotational fission due to sublimative outgassing ("SYORP" break-up) can occur outside of the Roche sphere in the distance range of 1-5 Roche radii. We use the Many Materials Orbital Sublimation (MaMOS) model to quantify the outgassing properties of three representative types of planetary materials: cores (iron), mantles (forsterite olivine) and comets (water ice), and characterise the resulting spin-up rate analytically by adopting SYORP coefficients in the range of $10^{-5}-10^{-3}$. We then compare this rate to that generated by the radiative YORP effect with YORP coefficients of $10^{-3}-10^{-2}$, and focus on planetesimals with radii of 0.1, 1.0, and 10 km. We find that for white dwarf cooling ages of up to $\sim$ 1 Gyr, sublimative fission of planetesimals and fragments $\lesssim$ 0.1 km in size due to water ice outgassing occur on observable timescales (within 10 yr), regardless if the spin-up is monotonic or stochastic. Further, these timescales are orders of magnitude shorter than the corresponding YORP fission timescales. For drier planetesimals, both iron and forsterite outgassing can be effective at 10-100 Myr cooling ages. Our results do not substantially differ for strengthless rubble piles versus objects with 1 kPa of internal strength. These findings add to growing evidence that gravitationally scattered comets and asteroids do not need to adopt pericentres within a white dwarf's Roche radius to eventually enrich, or pollute, the star with metals.

2605.21382 2026-05-21 math.GT math.QA math.SG

Flow loops and quantum groups

流环与量子群

Sunghyuk Park

AI总结 本文通过研究结的量子群不变量与莫尔斯流的动力学,定义了一个双变量级数不变量,用于描述结补集中的莫尔斯流环,推测该动力学级数与结补集的BPS q级数一致,后者源于量子群的Verma模,编码所有着色Jones多项式。

Comments 33 pages, many figures

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AI中文摘要

本文将两种看似不同的结研究方法联系起来:量子群不变量和莫尔斯流的动力学。对于纤维化结,我们通过计数莫尔斯流环在补集中的数量,定义了一个双变量级数不变量。该动力学级数被推测与结补集的BPS q级数一致,后者源于量子群的Verma模,并编码所有着色Jones多项式。我们证明了这种对应关系对于所有辫对称结成立。

英文摘要

This paper connects two seemingly different ways of studying knots: quantum group invariants and the dynamics of Morse flows. For fibered knots, we define a two-variable series invariant by counting Morse flow loops in the complement. This dynamical series is conjectured to agree with the BPS $q$-series of the knot complement, which arises from Verma modules for quantum groups and encodes all colored Jones polynomials. We prove this correspondence for all braid-homogeneous knots.

2605.21380 2026-05-21 quant-ph

Modeling and Resource Optimization for Quantum Oracles

量子 oracle 的建模与资源优化

Zhihang Li, Bo Zhao, Chuanbing Han, Jie Zhao, Jinchen Xu, Guoqiang Shu, Yimin Gao, Woji He, Zheng Shan

AI总结 本文提出了一种分层递归合成-评估模型,用于形式化描述和精确分析量子门复杂度,同时提出了一种自适应空间-深度权衡算法,在固定量子比特约束下生成 oracle 结构,并证明了该算法在给定量子比特数下达到最优门数。

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AI中文摘要

量子计算在特定应用中展现出对超算显著的优势,并在机器学习、密码学、金融等领域展现出广阔前景。量子 oracle 在许多量子算法中非常常见,oracle 资源消耗直接影响算法性能。然而,现有 oracle 设计往往表现出高资源开销和有限的兼容性。此外,结构化描述工具和复杂度分析方法缺乏。在本工作中,我们引入了一种分层递归合成-评估(HRSE)模型,能够实现 oracle 的形式化描述和精确量子门复杂度分析。基于该模型,我们提出了一种自适应空间-深度权衡(ASDT)算法,用于在固定量子比特约束下生成 oracle 结构。我们提供了一个理论证明,显示 ASDT 算法在给定量子比特数下达到最优门数。实验结果表明,与 W-cycle 方法相比,ASDT 算法在变量数分别为 10、15 和 20 时,将平均量子电路深度减少了 53.99%。

英文摘要

Quantum computing has demonstrated its significant advantage over supercomputing for specific applications and shown promising prospect, such as machine learning, cryptography, finance, etc.. Quantum oracles are very common in many quantum algorithms and oracle resource consumption directly affects algorithm performance. However, existing oracle designs often exhibit high resource overhead and limited compatibility. Moreover, structured description tools and complexity analysis methods are lacked. In this work, we introduces a Hierarchical Recursive Synthesis-Evaluation (HRSE) model, enabling formal description and precise quantum gate complexity analysis of oracles. Based on this model, we propose an Adaptive Space-depth Trade-off (ASDT) algorithm for generating oracle structures under a fixed qubit constraint. We provide a theoretical proof showing that the ASDT algorithm achieves the optimal gate count for a given number of qubits. Experimental results show that the ASDT algorithm reduces the average quantum circuit depth by 53.99% compared with the W-cycle approach, with the number of variables being 10, 15, and 20, respectively.

2605.21377 2026-05-21 hep-th hep-ph math-ph math.MP nucl-th

Causal UV completions of relativistic hydrodynamics

相对论流体动力学的因果UV完备性

Robbe Brants

AI总结 本文研究了相对论流体动力学的有效场论固有非因果性,并提出通过引入瞬时紫外模式来恢复因果性,同时探讨了非流体动力学模式的出现和限制。

Comments 9 pages

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AI中文摘要

相对论流体动力学成功地为许多非平衡系统的低能区域提供了有效场论描述。另一方面,本文证明了任何独立的流体动力学有效场论本质上都是非因果的,因此需要添加瞬时紫外模式以恢复因果性。这得以实现是因为耗散性流体动力学在光锥的大部分区域呈现指数衰减,使得在晚期时间尺度上仍能还原为流体动力学的因果描述。我们随后研究了这些因果紫外完备性中非流体动力学模式的出现和可能的限制。

英文摘要

Relativistic hydrodynamics successfully provides an effective field theory description for the low energy regime of many out-of-equilibrium systems. On the other hand, in this paper we proof that any stand-alone hydrodynamic EFT is inherently acausal and therefore requires the addition of transient UV modes in order to restore causality. This is made possible by the exponential decay of dissipative hydrodynamics in a majority of the lightcone, allowing the possibility of a causal description that still reduces to the hydrodynamic one at late timescales. We then investigate the emergence and possible restrictions of the non-hydrodynamic modes in these causal UV completions.

2605.21376 2026-05-21 cs.CY

Privacy Without Remedy: An Assessment of Data Broker Compliance with California Privacy Law

隐私无救济:对数据经纪商遵守加州隐私法的评估

Anna-Maria Gueorguieva, Jennifer King, Apoorva Panidapu, Daniel E Ho

AI总结 本文评估了数据经纪商对2018年加州消费者隐私法案(CCPA)和2023年删除法案的合规情况,发现仅有9%的数据经纪商在删除法案生效后完全符合透明度要求,并揭示了数据经纪商在消费者权利请求处理过程中存在的缺陷及改进方案。

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AI中文摘要

加州的消费者隐私法被广泛认为是美国最严格的隐私保护法律之一,是少数明确规范第三方实体(数据经纪商)购买和出售消费者数据的法律之一。我们提供了首次对数据经纪商遵守2018年加州消费者隐私法案(CCPA)和2023年删除法案的实证评估。首先,我们证明在删除法案生效后,522家注册的数据经纪商中仅有9%完全符合透明度要求,尽管我们发现随着时间的推移有所改善。其次,我们描述了数据经纪商在接收到的消费者权利请求数量上存在广泛异质性,许多报告没有收到任何请求。我们引入外部商业数据来探索与此变化相关的相关因素,这在一般缺乏对经纪商业务实践的透明度的情况下是一项挑战。第三,在对250家数据经纪商消费者请求流程的审计中,我们发现43%的数据经纪商使消费者无法行使所有隐私权利,64%的数据经纪商至少引入了一个设计特征,使消费者请求流程产生显著摩擦。最后,我们展示了这些缺陷源于合规决策的去中心化、执法限制和监管模糊性。我们提出了改进消费者隐私、经纪商实践透明度和遵守这些法律的改革方案。

英文摘要

California's consumer privacy law is widely deemed to be the most protected in the United States, one of the few to expressly regulate third party entities that buy and sell consumer data (data brokers). We offer the first empirical assessment of data broker compliance with the 2018 California Consumer Privacy Act (CCPA) and the 2023 Delete Act, which requires data brokers to register with the state and report consumer rights requests metrics annually. First, we demonstrate that only 9% of 522 registered data brokers were fully compliant with transparency requirements after the Delete Act took effect, although we do identify slight improvements over time. Second, we descriptively characterize wide heterogeneity across data brokers in the volume of consumer rights requests received, with many reporting none. We bring in external business data to explore correlates associated with this variation, a challenge given the general lack of opacity into broker business practices. Third, in an audit of a sample of 250 data brokers' consumers request processes, we find that 43% make it impossible for consumers to exercise all privacy rights and 64% introduce at least one design feature that creates substantial friction into the consumer request process. Last, we show how these deficiencies stem from the decentralization of compliance decisions to brokers themselves, enforcement limitations, and regulatory ambiguity. We articulate reforms that could improve consumer privacy, transparency in broker practices, and compliance with these laws.

2605.21375 2026-05-21 astro-ph.HE

Compact Object Astrophysics with Frontline Astrometry

用前沿天体测量法研究致密天体

P. Gandhi

AI总结 本文通过高精度天体测量法探讨了中子星和黑洞等致密天体的特性,分析了胎动 kick 和 Gaia 数据释放3 的最新结果,并展望了未来通过月球表面科学机会提升X射线收集面积和天体测量精度的潜力。

Comments Based on invited talk and proceedings for the ISSAC-2024 symposium, University of Delhi

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AI中文摘要

天体测量——即对天体位置和运动的精确测量——正在多个波长下进入微弧秒(μas)时代,使我们能够对所有质量尺度的致密天体获得新的见解。本文回顾了高精度天体测量如何推动我们对致密天体——中子星(NSs)和黑洞(BHs)——的理解。我们提供了高精度天体测量的背景,然后讨论了胎动 kick 和 Gaia 数据释放3(DR3)的最新结果。我们强调了吸积双星中质量依赖性异常速度的证据,并揭示了中子星和黑洞之间的相似性。下一代调查将发现银河系核中的 recoiling 超大质量黑洞(SMBHs),探讨引力波诱导 kick 的运作方式。利用月球表面的科学机会可能有助于在X射线中实现比目前可行的更大收集面积和天体测量精度。

英文摘要

Astrometry - the precise measurement of celestial positions and motions - is entering the micro-arcsecond ($μ$as) era at multiple wavelengths, enabling new insights on compact objects across all mass scales. Here we review how high-precision astrometry is advancing our understanding of compact objects - neutron stars (NSs) and black holes (BHs). We provide the context for high precision astrometry before discussing natal kicks and the latest results from Gaia Data Release 3 (DR3). We highlight the evidence for mass-dependent peculiar velocities of accreting binaries, and also reveal a close similarity between NSs and BHs. Next-generation surveys will find recoiling supermassive BHs (SMBHs) in galactic nuclei, exploring how gravitational-wave-induced kicks operate. Exploitation of scientific opportunities on the lunar surface could facilitate much larger collecting areas and astrometric precision in X-rays than currently feasible.

2605.21374 2026-05-21 cs.HC

Combating Harms of Generative AI in CS1 with Code Review Interviews and a Flipped Classroom

用代码审查面试和翻转课堂对抗生成AI在CS1中的负面影响

Peter Fowles, Erik Falor, Sulove Bhattarai, John Edwards, Seth Poulsen

AI总结 本文通过每周的口头代码审查评估和翻转课堂方法,探讨如何减少生成式AI对学生学习的负面影响,并发现学生在使用AI工具的情况下仍能保持良好的学习效果。

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AI中文摘要

背景和语境:大型语言模型(LLMs)比以往任何时候都更加易于获取和准确,这给计算机教育工作者带来了重大担忧。一个主要的担忧是学生使用LLMs来绕过理解概念和元认知策略所必需的努力。目标:我们贡献了一种独特的评估和构建学生理解的方法,即每周的口头代码审查评估。这些形成性评估激励学生理解他们提交的代码,无论代码是否由AI工具生成。我们还使用翻转课堂来提供时间让学生在课堂外学习概念,并为学生安排代码审查面试提供充足的时间。方法:为了本文,我们收集了三个学年的数据。我们分析学生考试成绩、键盘敲击日志和调查,以了解新的课程政策如何影响学生的学习、行为和态度。发现:考试结果的配对比较显示,2025年秋季的平均分数相比以前的学期有统计学上不显著的增加。键盘敲击日志显示,2025年秋季在编码作业中输入的字符数中粘贴的字符数显著增加,这指向更高的AI使用率。调查结果显示,2025年秋季末学生对代码审查的积极情绪,几乎所有负面反馈都可以通过更好的安排和更严格的技术助教培训来解决。意义:结合翻转课堂的口头代码审查似乎能够有效缓解LLM使用带来的负面影响,同时为学生提供自由实验这些工具的空间。我们的研究显示,尽管在编码作业中LLM的使用大幅增加,2025年秋季的学生在书面考试中仍显示出足够的材料理解能力。

英文摘要

Background and Context: Large Language Models (LLMs) are more accessible and accurate than ever before, raising significant concerns for computing educators. One major concern is students using LLMs to bypass the effort needed to understand concepts and metacognitive strategies essential for success in computer science. Objectives: We contribute a unique approach to assessing and building up student understanding through weekly oral code review assessments. These formative assessments incentivize students to understand their submitted code, regardless of whether or not the code was generated by AI tools. We also use a flipped classroom to provide time for students to learn concepts outside of class and provide ample time for students to schedule code review interviews. Methods: For this paper, we collected data from three semesters. We analyze student exam scores, keystroke logs, and surveys to understand how the new course policies affected student learning, behavior, and attitudes. Findings: Pairwise comparison of exam results reveals a statistically insignificant increase in average scores for Fall 2025 compared to previous semesters. Keystroke logs show a significant increase in characters pasted per total characters input into coding assignments in Fall 2025, pointing towards higher AI usage. Survey results show positive student sentiment towards code reviews at the end of Fall 2025, with nearly all negative feedback being addressable through better scheduling and more rigorous TA training. Implications: Oral code reviews with a flipped classroom appear to be effective at mitigating harms of LLM use while providing space for students to freely experiment with these tools. Our work suggests that students in Fall 2025 still show adequate understanding of material covered in written exams, despite dramatic increases in LLM usage for coding assignments.

2605.21373 2026-05-21 math.KT

The Abel Summation Method and Infinite Euler Characteristic

阿贝尔求和方法与无限欧拉特征

Thomas Huettemann, Dan Kucerovsky

AI总结 本文利用阿贝尔求和方法定义了无限链复形的有限性概念,并建立了此类复形的代数K理论,证明其非平凡性,同时展示了从环R的常规代数K理论到新K理论的自然映射,并证明其像包含一个自然的无限循环子群。

Comments 11 pages

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AI中文摘要

我们利用阿贝尔求和方法,为一个交换noetherian整环R上的无界链复形发展出一种有限性概念。定义了此类复形的代数K理论,并证明其非平凡性。我们还展示了一个从R的常规代数K理论到新K理论的自然映射,并证明其像包含一个自然的无限循环子群。

英文摘要

We develop a finiteness notion for unbounded chain complexes over a commutative noetherian integral domain $R$ employing the Abel summation method. The algebraic K-theory of such complexes is defined, and shown to be non-trivial. We also exhibit a natural map from the (usual) algebraic K-theory of $R$ into the new K-theory and show that its image contains a canonical infinite cyclic subgroup.