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Related papers: Speeding Up Cosmological Boltzmann Codes

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A challenging problem in solving the Boltzmann equation numerically is that the velocity space is approximated by a finite region. Therefore, most methods are based on a truncation technique and the computational cost is then very high if…

Analysis of PDEs · Mathematics 2013-06-14 Minh-Binh Tran

Weak lensing peak counts are a powerful statistical tool for constraining cosmological parameters. So far, this method has been applied only to surveys with relatively small areas, up to several hundred square degrees. As future surveys…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-01 Janis Fluri , Tomasz Kacprzak , Raphael Sgier , Alexandre Réfrégier , Adam Amara

A new approach for arbitrary dimension to the Friedmann cosmological models is presented. Taking suitable changes of the parameters of the spacetime the harmonic motion equations appear, where the curvature determines the angular frequency.…

General Relativity and Quantum Cosmology · Physics 2014-03-03 Rafael M. Rubio , Juan J. Salamanca

Recent progress has revealed a number of constraints that cosmological correlators and the closely related field-theoretic wavefunction must obey as a consequence of unitarity, locality, causality and the choice of initial state. When…

High Energy Physics - Theory · Physics 2024-03-20 Carlos Duaso Pueyo , Enrico Pajer

Heisenberg's uncertainty principle tells us that it is impossible to determine simultaneously the position of a photon crossing a telescope's aperture and its momentum. Super-resolution imaging techniques rely on modification of the…

Instrumentation and Methods for Astrophysics · Physics 2021-05-05 Gal Gumpel , Erez N Ribak

Simple analytic formulas are considered for the energy radiated in low frequency bremsstrahlung from fully ionized gases. A formula that has been frequently cited over many years turns out to have only a limited range of validity, more…

Astrophysics of Galaxies · Physics 2019-05-08 Steven Weinberg

Photometric calibration is essential to many computer vision applications. One of its key benefits is enhancing the performance of Visual SLAM, especially when it depends on a direct method for tracking, such as the standard KLT algorithm.…

Computer Vision and Pattern Recognition · Computer Science 2023-07-07 Jawad Haidar , Douaa Khalil , Daniel Asmar

Quantum tomography is an essential method of the photonic technology toolbox and is routinely used for evaluation of experimentally prepared states of light and characterization of devices transforming such states. The tomography procedure…

Quantum Physics · Physics 2018-12-18 Radim Hošák , Robert Stárek , Miroslav Ježek

We use the new cosmological recombination code, CosmoRec, for parameter estimation in the context of (future) precise measurements of the CMB temperature and polarization anisotropies. We address the question of how previously neglected…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 J. R. Shaw , J. Chluba

Large scale structure surveys will likely become the next leading cosmological probe. In our universe, matter perturbations are large on short distances and small at long scales, i.e. strongly coupled in the UV and weakly coupled in the IR.…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-17 John Joseph M. Carrasco , Mark P. Hertzberg , Leonardo Senatore

We present a numerically efficient and accurate implementation of the Passaglia-Hu effective fluid approximation for ultralight axions (ULAs) within the Boltzmann code CAMB. This method is specifically designed to evolve the axion field…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-24 Adam Moss , Lauren Gaughan , Anne M. Green

The past decade has seen a dramatic increase of practical applications of the microwave gyrosynchrotron emission for plasma diagnostics and three-dimensional modeling of solar flares and other astrophysical objects. This break-through…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Alexey A. Kuznetsov , Gregory D. Fleishman

We describe a new technique of quantum astrometry, which potentially can improve the resolution of optical interferometers by orders of magnitude. The approach requires fast imaging of single photons with sub-nanosecond resolution, greatly…

The ability to efficiently characterize the spatial correlations of entangled states of light is critical for applications of many quantum technologies such as quantum imaging. Here, we demonstrate highly efficient theoretical and…

Quantum Physics · Physics 2024-10-08 Mahtab Amooei , Girish Kulkarni , Jeremy Upham , Robert W. Boyd

Quantum imaging exploits the spatial correlations between photons to image object features with a higher resolution than a corresponding classical light source could achieve. Using a quantum correlated $N$-photon state, the method of…

Study of far-from-equilibrium thermalization dynamics in quantum materials, including the dynamics of different types of quasiparticles, is becoming increasingly crucial. However, the inherent complexity of either the full quantum…

Computational Physics · Physics 2021-03-17 Indrajit Wadgaonkar , Rishabh Jain , Marco Battiato

The exoplanet detection rate from gravitational microlensing has grown significantly in recent years thanks to a great enhancement of resources and improved observational strategy. Current observatories include ground-based wide-field…

Earth and Planetary Astrophysics · Physics 2017-04-17 A. Cassan

In this thesis we investigate several aspects related to the theory of fluctuations in the Cosmic Microwave Background. We develop a new algorithm to calculate the angular power spectrum of the anisotropies which is two orders of magnitude…

Astrophysics · Physics 2007-05-23 Matias Zaldarriaga

We generalize the application of small polaron theory to ultracold gases of Ref. [\onlinecite{jaksch_njp1}] to the case of Bose-Fermi mixtures, where both components are loaded into an optical lattice. In a suitable range of parameters, the…

Quantum Gases · Physics 2011-01-11 Antonio Privitera , Walter Hofstetter

Many optical measurement techniques, such as light scattering from wavelength-scale particles or detecting motion from a surface with an optical lever, encode information in a complex radiation pattern. Extracting all available information…

Quantum Physics · Physics 2025-12-22 Youssef Tawfik , Shan Hao , Thomas P. Purdy