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In the present paper we are concerned with a numerical algorithm for the approximation of the two-dimensional neural field equation with delay. We consider three numerical examples that have been analysed before by other authors and are…

Numerical Analysis · Mathematics 2015-11-04 Pedro M. Lima , Evelyn Buckwar

Relativistic quantum metrology provides an optimal strategy for the estimation of parameters encoded in quantum fields in flat and curved spacetime. These parameters usually correspond to physical quantities of interest such as proper…

Quantum Physics · Physics 2017-05-25 Dominik Šafránek , Jan Kohlrus , David Edward Bruschi , Antony R. Lee , Ivette Fuentes

Complex computer codes are often too time expensive to be directly used to perform uncertainty propagation studies, global sensitivity analysis or to solve optimization problems. A well known and widely used method to circumvent this…

Applications · Statistics 2008-04-06 Amandine Marrel , Bertrand Iooss , Francois Van Dorpe , Elena Volkova

A late time asymptotic perturbative analysis of curvature coupled complex scalar field models with accelerated cosmological expansion is carried out on the level of formal power series expansions. For this, algebraic analogues of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Roger Bieli

We present a comprehensive discussion on lattice techniques for the simulation of scalar and gauge field dynamics in an expanding universe. After reviewing the continuum formulation of scalar and gauge field interactions in Minkowski and…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-08 Daniel G. Figueroa , Adrien Florio , Francisco Torrenti , Wessel Valkenburg

Gravitational lensing has been identified as a powerful tool to address fundamental problems in astrophysics at different scales, ranging from exoplanet identification to dark energy and dark matter characterization in cosmology. Image…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-17 Andrés A. Plazas

Image simulations are essential tools for preparing and validating the analysis of current and future wide-field optical surveys. However, the galaxy models used as the basis for these simulations are typically limited to simple parametric…

Instrumentation and Methods for Astrophysics · Physics 2021-05-12 Francois Lanusse , Rachel Mandelbaum , Siamak Ravanbakhsh , Chun-Liang Li , Peter Freeman , Barnabas Poczos

Using cosmological N-body simulations, we study the abundance of local maxima (peaks) and minima (dips) identified in the smoothed distribution of halos and dark matter (DM) on scales of $10-100$s Mpcs. The simulations include Gaussian and…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-08 Adi Nusser , Matteo Biagetti , Vincent Desjacques

Many applications of Gaussian random fields and Gaussian random processes are limited by the computational complexity of evaluating the probability density function, which involves inverting the relevant covariance matrix. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-26 Theodor Bjorkmo , M. C. David Marsh

Automated searches for strong gravitational lensing in optical imaging survey datasets often employ machine learning and deep learning approaches. These techniques require more example systems to train the algorithms than have presently…

Instrumentation and Methods for Astrophysics · Physics 2021-02-08 Robert Morgan , Brian Nord , Simon Birrer , Joshua Yao-Yu Lin , Jason Poh

In recent years, the use of conformal transformation techniques has become widespread in the literature on gravitational theories alternative to general relativity, on cosmology, and on nonminimally coupled scalar fields. Typically, the…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Valerio Faraoni , Edgard Gunzig , Pasquale Nardone

The future astronomical imaging surveys are set to provide precise constraints on cosmological parameters, such as dark energy. However, production of synthetic data for these surveys, to test and validate analysis methods, suffers from a…

Gaussian graphical models are widely used to represent conditional dependence among random variables. In this paper, we propose a novel estimator for data arising from a group of Gaussian graphical models that are themselves dependent. A…

Machine Learning · Statistics 2016-09-01 Yuying Xie , Yufeng Liu , William Valdar

This paper deals with the Gaussian process based approximation of a code which can be run at different levels of accuracy. This method, which is a particular case of co-kriging, allows us to improve a surrogate model of a complex computer…

Statistics Theory · Mathematics 2012-09-25 Loic Le Gratiet

Recent developments in 3D Gaussian Splatting have made significant advances in surface reconstruction. However, scaling these methods to large-scale scenes remains challenging due to high computational demands and the complex dynamic…

Graphics · Computer Science 2025-06-24 Shihan Chen , Zhaojin Li , Zeyu Chen , Qingsong Yan , Gaoyang Shen , Ran Duan

Two algorithms are proposed to simulate space-time Gaussian random fields with a covariance function belonging to an extended Gneiting class, the definition of which depends on a completely monotone function associated with the spatial…

Computation · Statistics 2019-12-05 Denis Allard , Xavier Emery , Céline Lacaux , Christian Lantuéjoul

The large amount of cosmological data already available (and in the near future) makes necessary the development of efficient numerical codes. Many software products have been implemented to perform cosmological analyses considering one or…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-16 Sandro Dias Pinto Vitenti , Mariana Penna-Lima

Gaussian Markov random fields (GMRFs) are probabilistic graphical models widely used in spatial statistics and related fields to model dependencies over spatial structures. We establish a formal connection between GMRFs and convolutional…

Machine Learning · Statistics 2020-08-11 Per Sidén , Fredrik Lindsten

We investigate the non-gaussian properties of cosmic-string-seeded linear density perturbations with cold and hot dark matter backgrounds, using high-resolution numerical simulations. We compute the one-point probability density function of…

Astrophysics · Physics 2009-10-30 P. P. Avelino , E. P. S. Shellard , J. H. P. Wu , B. Allen

Neural image representations have emerged as a promising approach for encoding and rendering visual data. Combined with learning-based workflows, they demonstrate impressive trade-offs between visual fidelity and memory footprint. Existing…

Computer Vision and Pattern Recognition · Computer Science 2025-05-08 Yunxiang Zhang , Bingxuan Li , Alexandr Kuznetsov , Akshay Jindal , Stavros Diolatzis , Kenneth Chen , Anton Sochenov , Anton Kaplanyan , Qi Sun