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We study the spectrum of inner-product kernel matrices, i.e., $n \times n$ matrices with entries $h (\langle \textbf{x}_i ,\textbf{x}_j \rangle/d)$ where the $( \textbf{x}_i)_{i \leq n}$ are i.i.d.~random covariates in $\mathbb{R}^d$. In…

Statistics Theory · Mathematics 2022-04-25 Theodor Misiakiewicz

The variation in mean-square nuclear charge radius of xenon isotopes was measured utilizing a new method based on extreme ultraviolet spectroscopy of highly charged Na-like ions. The isotope shift of the Na-like D1 (3s $^{2}$S$_{1/2}$ - 3p…

Quantum chemistry calculations are often performed using atom-centered basis sets which are chosen to balance accuracy and cost. While they are systematically improvable, the total energy converges slowly with basis set size towards the…

Chemical Physics · Physics 2026-05-18 Nicolas Grimblat , Gabriel Klassen , Guido Falk von Rudorff

This work describes the formalism for estimating thermonuclear reaction rates for astrophysical applications, emphasizing modern statistical approaches such as Monte-Carlo sampling and Bayesian models. We discuss related topics including…

Solar and Stellar Astrophysics · Physics 2026-03-11 Christian Iliadis , Richard Longland , Kiana Setoodehnia , Caleb Marshall , Peter Mohr , Athanasios Psaltis

Kernel ridge regression (KRR) is a foundational tool in machine learning, with recent work emphasizing its connections to neural networks. However, existing theory primarily addresses the i.i.d. setting, while real-world data often exhibits…

Machine Learning · Statistics 2025-10-20 Dechen Zhang , Zhenmei Shi , Yi Zhang , Yingyu Liang , Difan Zou

Reinforcement Learning (RL) problems are being considered under increasingly more complex structures. While tabular and linear models have been thoroughly explored, the analytical study of RL under nonlinear function approximation,…

Machine Learning · Computer Science 2025-09-12 Aya Kayal , Sattar Vakili , Laura Toni , Alberto Bernacchia

In this paper, we develop a quadrature framework for large-scale kernel machines via a numerical integration representation. Considering that the integration domain and measure of typical kernels, e.g., Gaussian kernels, arc-cosine kernels,…

Machine Learning · Computer Science 2021-06-14 Fanghui Liu , Xiaolin Huang , Yudong Chen , Johan A. K. Suykens

Study of the ground-state properties of Kr, Sr and Zr isotopes has been performed in the framework of the relativistic mean field (RMF) theory using the recently proposed relativistic parameter set NL-SH. It is shown that the RMF theory…

Nuclear Theory · Physics 2016-09-08 G. A. Lalazissis , M. M. Sharma

Global and national efforts to deliver high-quality nuclear data to users have a broad impact across applications such as national security, reactor operation, basic science, medical fields, and more. Cross section evaluation is a large…

Computational Physics · Physics 2025-05-08 Noah A. W. Walton , Oleksii Zivenko , William Fritsch , Jacob Forbes , Amanda Lewis , Jesse Brown , Vlad Sobes

The nuclear recoil effect, known also as the mass shift, is one of theoretical contributions to the energy levels in muonic atoms. Accurate theoretical predictions are therefore needed for extracting e.g. the nuclear charge radii from…

Atomic Physics · Physics 2023-12-08 Vladimir A. Yerokhin , Natalia S. Oreshkina

This paper proposes and studies a numerical method for approximation of posterior expectations based on interpolation with a Stein reproducing kernel. Finite-sample-size bounds on the approximation error are established for posterior…

Statistics Theory · Mathematics 2022-01-12 Alessandro Barp , Chris. J. Oates , Emilio Porcu , Mark Girolami

We present a high-accuracy calculation of the deuteron structure radius in chiral effective field theory. Our analysis employs the state-of-the-art semilocal two-nucleon potentials and takes into account two-body contributions to the charge…

Nuclear Theory · Physics 2020-03-06 A. A. Filin , V. Baru , E. Epelbaum , H. Krebs , D. Möller , P. Reinert

Lattice QCD calculations of nucleon form factors are restricted to discrete values of the Euclidean four-momentum transfer. Therefore, the extraction of radii typically relies on parametrizing and fitting the lattice QCD data to obtain its…

High Energy Physics - Lattice · Physics 2020-07-01 Constantia Alexandrou , Kyriakos Hadjiyiannakou , Giannis Koutsou , Konstantin Ottnad , Marcus Petschlies

The nuclear charge radius of $^{12}$Be was precisely determined using the technique of collinear laser spectroscopy on the $2s_{1/2}\rightarrow 2p_{1/2, 3/2}$ transition in the Be$^{+}$ ion. The mean square charge radius increases from…

Collinear-laser spectroscopy with bunched-beams technique was used for the study of neutron deficient Rb isotopes, out to $^{74}$Rb ($N=Z=37$) at TRIUMF. The measured hyperfine coupling constants of $^{76,78m}$Rb were in agreement with…

In this paper, we propose a fast surrogate leverage weighted sampling strategy to generate refined random Fourier features for kernel approximation. Compared to the current state-of-the-art method that uses the leverage weighted scheme…

Machine Learning · Computer Science 2019-11-22 Fanghui Liu , Xiaolin Huang , Yudong Chen , Jie Yang , Johan A. K. Suykens

Complete flavour decompositions of the scalar, axial and tensor charges of the proton, deuteron, diproton and $^3$He at SU(3)-symmetric values of the quark masses corresponding to a pion mass $m_\pi\sim806$ MeV are determined using lattice…

Kernel methods give powerful, flexible, and theoretically grounded approaches to solving many problems in machine learning. The standard approach, however, requires pairwise evaluations of a kernel function, which can lead to scalability…

Machine Learning · Computer Science 2021-04-08 Danica J. Sutherland , Jeff Schneider

We propose an experiment to measure the nuclear charge radii of light elements with up to 20~times higher accuracy. These are essential both for understanding nuclear physics at low energies, and for experimental and theoretical…

Reinforcement learning utilizing kernel ridge regression to predict the expected value function represents a powerful method with great representational capacity. This setting is a highly versatile framework amenable to analytical results.…

Machine Learning · Computer Science 2024-11-01 Sattar Vakili , Julia Olkhovskaya
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