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Related papers: A Regularized Free Form Estimator for Dark Energy

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In this paper, we develop a relative error bound for nuclear norm regularized matrix completion, with the focus on the completion of full-rank matrices. Under the assumption that the top eigenspaces of the target matrix are incoherent, we…

Machine Learning · Computer Science 2024-05-30 Lijun Zhang , Tianbao Yang , Rong Jin , Zhi-Hua Zhou

The understanding of the accelerated expansion of the Universe poses one of the most fundamental questions in physics and cosmology today. Whether or not the acceleration is driven by some form of dark energy, and in the absence of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 E. Piedipalumbo , E. Della Moglie , M. De Laurentis , P. Scudellaro

The current paper provides a comprehensive examination of a dark energy cosmological model in the classical regime, in which a generic scalar field is regarded as a dark energy source. Einstein's field equations are solved in model…

General Relativity and Quantum Cosmology · Physics 2022-09-07 Ritika Nagpal , Shibesh Kumar Jas Pacif , Abhishek Parida

The response of a nucleus to an electromagnetic probe is a key quantity to simulate photabsorption or photodeexcitation processes. For large calculations at the scale of the entire mass table, this response can be estimated by linear…

Nuclear Theory · Physics 2024-04-05 Tong Li , Nicolas Schunck

We describe two fitting schemes that aim to represent the high-density part of realistic equations of state for numerical simulations such as neutron star oscillations. The low-density part of the equation of state is represented by an…

High Energy Astrophysical Phenomena · Physics 2024-05-20 Gaël Servignat , Philip J. Davis , Jérôme Novak , Micaela Oertel , José A. Pons

We present a novel energy-based numerical analysis of semilinear diffusion-reaction boundary value problems. Based on a suitable variational setting, the proposed computational scheme can be seen as an energy minimisation approach. More…

Numerical Analysis · Mathematics 2022-02-16 Mario Amrein , Pascal Heid , Thomas P. Wihler

A Maximum Likelihood recursive state estimator is derived for non-linear and non-Gaussian state-space models. The estimator combines a particle filter to generate the conditional density and the Expectation Maximization algorithm to compute…

Methodology · Statistics 2021-03-22 Mohammad S. Ramadan , Robert R. Bitmead

An adaptive regularization strategy for stabilizing Newton-like iterations on a coarse mesh is developed in the context of adaptive finite element methods for nonlinear PDE. Existence, uniqueness and approximation properties are known for…

Numerical Analysis · Mathematics 2015-01-27 Sara Pollock

We develop a method for computing exact one-loop quantum corrections to the energies of static classical backgrounds in renormalizable quantum field theories. We use a continuum density of states formalism to construct a regularized Casimir…

High Energy Physics - Theory · Physics 2009-09-25 N. Graham

Based on a suite of state-of-the-art high-resolution $N$-body simulations, we revisit the so-called halofit model (Smith et al. 2003) as an accurate fitting formula for the nonlinear matter power spectrum. While the halofit model has been…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Ryuichi Takahashi , Masanori Sato , Takahiro Nishimichi , Atsushi Taruya , Masamune Oguri

When classical particle filtering algorithms are used for maximum likelihood parameter estimation in nonlinear state-space models, a key challenge is that estimates of the likelihood function and its derivatives are inherently noisy. The…

Computation · Statistics 2017-11-30 Andreas Svensson , Fredrik Lindsten , Thomas B. Schön

From the statistical learning perspective, complexity control via explicit regularization is a necessity for improving the generalization of over-parameterized models. However, the impressive generalization performance of neural networks…

Machine Learning · Computer Science 2021-02-09 Taejong Joo , Uijung Chung

Regularization plays an important role in solving ill-posed problems by adding extra information about the desired solution, such as sparsity. Many regularization terms usually involve some vector norm, e.g., $L_1$ and $L_2$ norms. In this…

Numerical Analysis · Mathematics 2021-03-10 Weihong Guo , Yifei Lou , Jing Qin , Ming Yan

We study the problem of finding structured low-rank matrices using nuclear norm regularization where the structure is encoded by a linear map. In contrast to most known approaches for linearly structured rank minimization, we do not (a) use…

Systems and Control · Computer Science 2015-09-09 Adams Wei Yu , Wanli Ma , Yaoliang Yu , Jaime G. Carbonell , Suvrit Sra

Approximate dynamic programming has been used successfully in a large variety of domains, but it relies on a small set of provided approximation features to calculate solutions reliably. Large and rich sets of features can cause existing…

Artificial Intelligence · Computer Science 2015-03-17 Marek Petrik , Gavin Taylor , Ron Parr , Shlomo Zilberstein

In this paper, we present a novel optimization algorithm designed specifically for estimating state-space models to deal with heavy-tailed measurement noise and constraints. Our algorithm addresses two significant limitations found in…

Signal Processing · Electrical Eng. & Systems 2024-11-19 Yifan Yu , Shengjie Xiu , Daniel P. Palomar

For electrical impedance tomography (EIT), most practical reconstruction methods are based on linearizing the underlying non-linear inverse problem. Recently, it has been shown that the linearized problem still contains the exact shape…

Numerical Analysis · Mathematics 2018-11-20 Moon Kyung Choi , Bastian Harrach , Jin Keun Seo

The power method is one of the most fundamental tools for extracting top principal components from data through low-rank matrix approximation. Yet, when the target rank is large, the cost of matrix multiplication associated with this…

Numerical Analysis · Mathematics 2026-05-12 Shabarish Chenakkod , Michał Dereziński

We compare current and forecasted constraints on dynamical dark energy models from Type Ia supernovae and the cosmic microwave background using figures of merit based on the volume of the allowed dark energy parameter space. For a…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Michael J. Mortonson , Dragan Huterer , Wayne Hu

Regression by composition provides a flexible framework for constructing conditional distributions through sequential group actions. However, when multiple flows act on the same distribution, the model becomes non-identifiable, leading to…

Methodology · Statistics 2026-03-30 Safaa K. Kadhem