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In this article, we describe a new estimate of the Cosmic Microwave Background (CMB) intensity map reconstructed by a joint analysis of the full Planck 2015 data (PR2) and WMAP nine-years. It provides more than a mere update of the CMB map…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 J. Bobin , F. Sureau , J-L Starck

We develop a method of reconstructing the lensing field from lensed CMB temperature and polarization maps in real space as an alternative to the harmonic space estimators currently in use by extending an existing real space lensing…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 Heather Prince , Kavilan Moodley , Jethro Ridl , Martin Bucher

We study the possibility for constraining the topology of the Universe by means of the matched circles statistic applied to polarised cosmic microwave background (CMB) anisotropy maps. The advantages of using the CMB polarisation maps in…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-09 P. Bielewicz , A. J. Banday , K. M. Gorski

This paper combines the use of high order finite element methods with parallel preconditioners of domain decomposition type for solving electromagnetic problems arising from brain microwave imaging. The numerical algorithms involved in such…

Computational Physics · Physics 2020-03-23 M. Bonazzoli , V. Dolean , F. Rapetti , P. -H. Tournier

Preconditioners are generally essential for fast convergence in the iterative solution of linear systems of equations. However, the computation of a good preconditioner can be expensive. So, while solving a sequence of many linear systems,…

Numerical Analysis · Mathematics 2020-12-21 Arielle Grim-McNally , Eric de Sturler , Serkan Gugercin

We study a two-stage mixed-integer linear program (MILP) with more than 1 million binary variables in the second stage. We develop a two-level approach by constructing a semi-coarse model (coarsened with respect to variables) and a coarse…

Optimization and Control · Mathematics 2015-04-20 Fu Lin , Sven Leyffer , Todd Munson

The Cosmic Microwave Background (CMB) is an abundant source of cosmological information. However, this information is encoded in non-trivial ways in a signal that is difficult to observe. The resulting challenges in extracting this…

Astrophysics · Physics 2014-10-13 Benjamin D. Wandelt

Current large-aperture cosmic microwave background (CMB) telescopes have nearly maximized the number of detectors that can be illuminated while maintaining diffraction-limited image quality. The polarization-sensitive detector arrays being…

Instrumentation and Methods for Astrophysics · Physics 2016-04-20 Michael D. Niemack

We describe an algorithm to generate temperature and polarization maps of the cosmic microwave background radiation containing non-Gaussianity of arbitrary local type. We apply an optimized quadrature scheme that allows us to predict and…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-04 Franz Elsner , Benjamin D. Wandelt

Preconditioning techniques are crucial for enhancing the efficiency of solving large-scale linear equation systems that arise from partial differential equation (PDE) discretization. These techniques, such as Incomplete Cholesky…

Machine Learning · Computer Science 2024-12-11 Rui Li , Song Wang , Chen Wang

Cosmic microwave background (CMB) radiation data obtained by different experiments contain, besides the desired signal, a superposition of microwave sky contributions. We present a fast and robust method, using a wavelet decomposition on…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 R. Fernández-Cobos , P. Vielva , R. B. Barreiro , E. Martínez-González

Successful autonomous robot navigation in off-road domains requires the ability to generate high-quality terrain costmaps that are able to both generalize well over a wide variety of terrains and rapidly adapt relative costs at test time to…

Robotics · Computer Science 2026-02-03 Luisa Mao , Garrett Warnell , Peter Stone , Joydeep Biswas

The cosmic microwave background (CMB) temperature maps published by the Wilkinson Microwave Anisotropy Probe (WMAP) team are found to be inconsistent with the differential time-ordered data (TOD), from which the maps are reconstructed. The…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-22 Hao Liu , Ti-Pei Li

We apply state-of-the art data analysis methods to a number of fictitious CMB mapping experiments, including 1/f noise, distilling the cosmological information from time-ordered data to maps to power spectrum estimates, and find that in all…

Astrophysics · Physics 2008-11-26 Max Tegmark

Time-ordered data (TOD) from ground-based CMB experiments are generally filtered before map-making to remove or reduce the contamination from the ground and the atmospheric emissions. However, when the observation region contains strong…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-28 Zhaoxuan Zhang , Lu Huang , Yang Liu , Si-Yu Li , Le Zhang , Hao Liu

This paper presents estimates of the convergence rate and complexity of an algebraic multilevel preconditioner based on piecewise constant coarse vector spaces applied to the graph Laplacian. A bound is derived on the energy norm of the…

Numerical Analysis · Mathematics 2012-04-19 James Brannick , Yao Chen , Johannes Kraus , Ludmil Zikatanov

We show that the cosmic birefringence and miscalibrated polarisation angles can be determined simultaneously by cosmic microwave background (CMB) experiments using the cross-correlation between $E$- and $B$-mode polarisation data. This is…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-30 Yuto Minami , Hiroki Ochi , Kiyotomo Ichiki , Nobuhiko Katayama , Eiichiro Komatsu , Tomotake Matsumura

The cosmic microwave background (CMB), carrying the inhomogeneous information of the very early universe, is of great significance for understanding the origin and evolution of our universe. However, observational CMB maps contain serious…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-12 Guo-Jian Wang , Hong-Liang Shi , Ye-Peng Yan , Jun-Qing Xia , Yan-Yun Zhao , Si-Yu Li , Jun-Feng Li

In recent years, topology optimization has been developed sufficiently and many researchers have concentrated on enhancing to computationally numerical algorithms for computational effectiveness of this method. Along with the development of…

Numerical Analysis · Mathematics 2023-01-19 Nam G. Luu , Thanh T. Banh

Gaussian process hyperparameter optimization requires linear solves with, and log-determinants of, large kernel matrices. Iterative numerical techniques are becoming popular to scale to larger datasets, relying on the conjugate gradient…

Machine Learning · Computer Science 2022-06-22 Jonathan Wenger , Geoff Pleiss , Philipp Hennig , John P. Cunningham , Jacob R. Gardner