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Related papers: On the stability of covariant BSSN formulation

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We address the problem of observation noise misspecification in Bayesian filtering of dynamical systems via recent advances in generalised Bayesian inference. Mis-match in tail decay between the true data generating process and an assumed…

Statistics Theory · Mathematics 2026-05-27 Hans Reimann , Sebastian Reich

This contribution presents an improved low-order 3D finite element formulation with hourglass stabilization using automatic differentiation (AD). Here, the former Q1STc formulation is enhanced by an approximation-free computation of the…

Computational Engineering, Finance, and Science · Computer Science 2025-02-21 Njomza Pacolli , Ahmad Awad , Jannick Kehls , Bjorn Sauren , Sven Klinkel , Stefanie Reese , Hagen Holthusen

The structure of the renormalization-group flows in a model with three quartic coupling constants is studied within the $\epsilon$-expansion method up to three-loop order. Twofold degeneracy of the eigenvalue exponents for the…

Statistical Mechanics · Physics 2009-10-31 Andrei Mudrov , Konstantin Varnashev

The scalar auxiliary variable (SAV) approach of Shen et al. (2018), which presents a novel way to discretize a large class of gradient flows, has been extended and improved by many authors for general dissipative systems. In this work we…

Numerical Analysis · Mathematics 2025-01-16 Kei Fong Lam , Ru Wang

The study of third-order statistics in large-scale structure analyses has been hampered by the increased complexity of bispectrum estimators (compared to power spectra), the large dimensionality of the data vector, and the difficulty in…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-20 Lea Harscouet , Jessica A. Cowell , Julia Ereza , David Alonso , Hugo Camacho , Andrina Nicola , Anže Slosar

The paper presents an algebraic framework for optimization problems expressible as Valued Constraint Satisfaction Problems. Our results generalize the algebraic framework for the decision version (CSPs) provided by Bulatov et al. [SICOMP…

Computational Complexity · Computer Science 2016-05-03 Marcin Kozik , Joanna Ochremiak

This article concerns the stability of a model for mass-spring systems with positive damping and negative stiness. It is well known that when the coefficients are frozen in time the system is unstable. Here we find conditions on the…

Classical Analysis and ODEs · Mathematics 2007-06-01 Julio G. Dix , Cesar A. Terrero-Escalante

We develop a new, efficient code for solving the second-order Einstein-Boltzmann equations, and use it to estimate the intrinsic CMB non-Gaussianity arising from the non-linear evolution of density perturbations. The full calculation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Guido W. Pettinari , Christian Fidler , Robert Crittenden , Kazuya Koyama , David Wands

We revisit the inverse problem of reconstructing a spatially varying diffusion coefficient in stationary elliptic equations from boundary Cauchy data. From a theoretical perspective, we introduce a gradient-weighted modification of the…

Numerical Analysis · Mathematics 2026-02-05 Sahat Pandapotan Nainggolan , Julius Fergy Tiongson Rabago , Hirofumi Notsu

In this work, we study the positive definiteness (PDness) problem in covariance matrix estimation. For high dimensional data, many regularized estimators are proposed under structural assumptions on the true covariance matrix including…

Methodology · Statistics 2019-04-16 Young-Geun Choi , Johan Lim , Anindya Roy , Junyong Park

A combination of control Lyapunov functions (CLFs) and control barrier functions (CBFs) forms an efficient framework for addressing control challenges in safe stabilization. In our previous research, we developed an analytical control…

Systems and Control · Electrical Eng. & Systems 2023-12-06 Ming Li , Zhiyong Sun

A possible avenue towards the covariant formulation of the bosonic Matrix Theory is explored. The approach is guided by the known covariant description of the bosonic membrane. We point out various problems with this particular…

High Energy Physics - Theory · Physics 2009-10-30 H. Awata , D. Minic

This paper addresses the development of a covariance matrix self-adaptation evolution strategy (CMSA-ES) for solving optimization problems with linear constraints. The proposed algorithm is referred to as Linear Constraint CMSA-ES…

Neural and Evolutionary Computing · Computer Science 2018-09-24 Patrick Spettel , Hans-Georg Beyer , Michael Hellwig

We introduce extensions of stability selection, a method to stabilise variable selection methods introduced by Meinshausen and B\"uhlmann (J R Stat Soc 72:417-473, 2010). We propose to apply a base selection method repeatedly to random…

Methodology · Statistics 2016-10-26 Andre Beinrucker , Ürün Dogan , Gilles Blanchard

Quality gain is the expected relative improvement of the function value in a single step of a search algorithm. Quality gain analysis reveals the dependencies of the quality gain on the parameters of a search algorithm, based on which one…

Optimization and Control · Mathematics 2018-05-14 Youhei Akimoto , Anne Auger , Nikolaus Hansen

The numerical analysis of stochastic time fractional evolution equations presents considerable challenges due to the limited regularity of the model caused by the nonlocal operator and the presence of noise. The existing time-stepping…

Numerical Analysis · Mathematics 2024-01-22 Minghua Chen , Jiankang Shi , Zhen Song , Yubin Yan , Zhi Zhou

The flux reconstruction (FR) approach offers a flexible framework for describing a range of high-order numerical schemes; including nodal discontinuous Galerkin and spectral difference schemes. This is accomplished through the use of…

Numerical Analysis · Mathematics 2020-06-25 Will Trojak , Freddie Witherden

We make a comprehensive investigation of the observational effect of the inflation consistency relation. We focus on the general single-field inflation model with the consistency relation $r=-8c_s n_t$, and investigate the observational…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Cheng Cheng , Qing-Guo Huang , Xiao-Dong Li , Yin-Zhe Ma

In this paper, we propose a general framework for designing sensing matrix $\boldsymbol{A} \in \mathbb{R}^{d\times p}$, for estimation of sparse covariance matrix from compressed measurements of the form $\boldsymbol{y} =…

Information Theory · Computer Science 2022-11-16 Muralikrishnna G. Sethuraman , Hang Zhang , Faramarz Fekri

We present a notion of bilinear stability, which is to numerical stability what bilinear complexity is to time complexity. In bilinear complexity, an algorithm for evaluating a bilinear operator $\beta : \mathbb{U} \times \mathbb{V} \to…

Numerical Analysis · Mathematics 2023-10-13 Zhen Dai , Lek-Heng Lim
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