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Related papers: Topological Analysis of High-Resolution CMB Maps

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Scanning probe microscopy (SPM) is a powerful technique for mapping nanoscale surface properties through tip-sample interactions. Thermal scanning-probe lithography (tSPL) is an advanced SPM variant that uses a silicon tip on a heated…

We propose and implement a fast, universally applicable method for extracting the angular power spectrum C_l from CMB temperature maps by first estimating the correlation function \xi(\theta). Our procedure recovers the C_l's using N^2 (but…

We present a method for computing the topological entropy of one-dimensional maps. As an approximation scheme, the algorithm converges rapidly and provides both upper and lower bounds.

chao-dyn · Physics 2009-10-22 N. J. Balmforth , E. A. Spiegel , C. Tresser

Topological data analysis provides a collection of tools to encapsulate and summarize the shape of data. Currently it is mainly restricted to \emph{mapper algorithm} and \emph{persistent homology}. In this paper we introduce new…

Algebraic Topology · Mathematics 2019-01-23 Paweł Dłotko

We propose an alternative formalism to simulate CMB temperature maps in $\Lambda$CDM universes with nontrivial spatial topologies. This formalism avoids the need to explicitly compute the eigenmodes of the Laplacian operator in the spatial…

Astrophysics · Physics 2008-11-26 W. S. Hipolito-Ricaldi , G. I. Gomero

We present a new technique for constraining the topology of the universe. The method exploits the existence of correlations in the phases of the spherical harmonic coefficients of the CMB temperature pattern associated with matched pairs of…

Astrophysics · Physics 2009-11-10 Patrick Dineen , Graca Rocha , Peter Coles

Efficient searches for electromagnetic counterparts to gravitational wave, high-energy neutrino, and gamma-ray burst events demand rapid processing of image arithmetic and geometry set operations in a database to cross-match galaxy…

Instrumentation and Methods for Astrophysics · Physics 2022-04-28 Leo P. Singer , B. Parazin , Michael W. Coughlin , Joshua S. Bloom , Arien Crellin-Quick , Daniel A. Goldstein , Stéfan van der Walt

The predictions of mean-field electrodynamics can now be probed using direct numerical simulations of random flows and magnetic fields. When modelling astrophysical MHD, it is important to verify that such simulations are in agreement with…

Data Analysis, Statistics and Probability · Physics 2018-09-12 Irina Makarenko , Paul Bushby , Andrew Fletcher , Robin Henderson , Nikolay Makarenko , Anvar Shukurov

We present a simple approximation that can speed up the computation of the mode-coupling matrices, which are usually the bottleneck for computing unbiased angular power spectra, as well as their associated covariance matrices, of the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-04 Thibaut Louis , Sigurd Naess , Xavier Garrido , Anthony Challinor

Topological analysis of the magnetic field in simulated plasmas allows the study of various physical phenomena in a wide range of settings. One such application is magnetic reconnection, a phenomenon related to the dynamics of the magnetic…

We present a parsimonious deep learning weather prediction model to forecast seven atmospheric variables with 3-h time resolution for up to one-year lead times on a 110-km global mesh using the Hierarchical Equal Area isoLatitude…

Topological correctness plays a critical role in many image segmentation tasks, yet most networks are trained using pixel-wise loss functions, such as Dice, neglecting topological accuracy. Existing topology-aware methods often lack robust…

Computer Vision and Pattern Recognition · Computer Science 2025-04-21 Laurin Lux , Alexander H. Berger , Alexander Weers , Nico Stucki , Daniel Rueckert , Ulrich Bauer , Johannes C. Paetzold

Mapping is an important part of many robotic applications. In order to measure the performance of the mapping process we have to measure the quality of its result: the map. The map is essential for robotic algorithms like localization and…

Robotics · Computer Science 2019-12-04 Sören Schwertfeger , Tianyan Yu

We study the ellipticity of contour lines in the sky maps of the cosmic microwave background (CMB) as well as other measures of elongation. The sensitivity of the elongation on the resolution of the CMB maps which depends on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Ralf Aurich , Holger S. Janzer , Sven Lustig , Frank Steiner

The measurements of CMB anisotropy have opened up a window for probing the global topology of the universe on length scales comparable to and beyond the Hubble radius. We have developed a new method for calculating the CMB anisotropy in…

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Dmitry Pogosyan , J. Richard Bond

Our goal in this paper is to apply the topological signal processing (TSP) framework to the analysis of 3D Point Clouds (PCs) represented on simplicial complexes. Building on Discrete Exterior Calculus (DEC) theory for vector fields, we…

Signal Processing · Electrical Eng. & Systems 2026-02-24 Tiziana Cattai , Stefania Sardellitti , Stefania Colonnese , Sergio Barbarossa

Computational topology is an area that revisits topological problems from an algorithmic point of view, and develops topological tools for improved algorithms. We survey results in computational topology that are concerned with graphs drawn…

Computational Geometry · Computer Science 2017-09-06 Éric Colin de Verdière

The open-source Python package Gammapy, developed for the high-level analysis of gamma-ray data, requires gamma-like event lists combined with the corresponding instrument response functions. For a morphological analysis, these data have to…

Instrumentation and Methods for Astrophysics · Physics 2023-02-23 Simone Mender , Lena Linhoff , Tarek Hassan , Cosimo Nigro , Dominik Elsässer

Cosmological measurements require the calculation of nontrivial quantities over large datasets. The next generation of survey telescopes (such as DES, PanSTARRS, and LSST) will yield measurements of billions of galaxies. The scale of these…

Instrumentation and Methods for Astrophysics · Physics 2012-12-10 Deborah Bard , Matthew Bellis , Mark T. Allen , Hasmik Yepremyan , Jan M. Kratochvil

Molecular mapping is a supervised method exploiting the spectral diversity of integral field spectrographs to detect and characterize resolved exoplanets blurred into the stellar halo. We present an evolution of the method to remove the…

Earth and Planetary Astrophysics · Physics 2024-02-14 F. Kiefer , M. Bonnefoy , B. Charnay , A. Boccaletti , A. -M. Lagrange , G. Chauvin , B. Bézard , M. Mâlin