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We develop the first algorithm able to jointly compute the maximum {\it a posteriori} estimate of the Cosmic Microwave Background (CMB) temperature and polarization fields, the gravitational potential by which they are lensed, and…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Marius Millea , Ethan Anderes , Benjamin D. Wandelt

We derive an analytic expression for the mean magnification due to strong gravitational lensing, using a simple lens model, a singular isothermal sphere embedded in an external shear field. We compute separate expressions for 2-image and…

Astrophysics · Physics 2009-11-07 Tehani K. Finch , Lisa P. Carlivati , Joshua N. Winn , Paul L. Schechter

We present a new estimation method for mapping the gravitational lensing potential from observed CMB intensity and polarization fields. Our method uses Bayesian techniques to estimate the average curvature of the potential over small local…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-23 Ethan Anderes , Lloyd Knox , Alexander van Engelen

We describe a new method for analyzing gravitational lens images, for the case where the source light distribution is pixelized. The method is suitable for high resolution, high S/N data of a multiply-imaged extended source. For a given…

Astrophysics · Physics 2009-11-07 Steve Warren , Simon Dye

The paper discusses the improvement of the accuracy of an inertial navigation system created on the basis of MEMS sensors using machine learning (ML) methods. As input data for the classifier, we used infor-mation obtained from a developed…

Robotics · Computer Science 2022-12-08 Aleksandr N. Grekov , Aleksei A. Kabanov , Sergei Yu. Alekseev

We have developed a new three-dimensional algorithm, based on the standard P$^3$M method, for computing deflections due to weak gravitational lensing. We compare the results of this method with those of the two-dimensional planar approach,…

Astrophysics · Physics 2009-10-31 H. M. P. Couchman , Andrew J. Barber , Peter A. Thomas

We continue our study of the optical properties of the solar gravitational lens (SGL). Taking the next step beyond representing it as an idealized monopole, we now characterize the gravitational field of the Sun using an infinite series of…

General Relativity and Quantum Cosmology · Physics 2021-03-30 Slava G. Turyshev , Viktor T. Toth

We present a novel, model-independent technique for fitting the cross-component of weak lensing shear, $\gamma_\times$, along a line of sight by combining kinematic and photometric measurements of a single lensed galaxy. Rather than relying…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-26 Christopher Hopp , David Wittman

Gravitational wave (GW) astronomy offers the potential to probe the wave-optics regime of gravitational lensing. Wave optics (WO) effects are relevant at low frequencies, when the wavelength is comparable to the characteristic lensing time…

General Relativity and Quantum Cosmology · Physics 2023-09-06 Giovanni Tambalo , Miguel Zumalacárregui , Liang Dai , Mark Ho-Yeuk Cheung

Gravitational lensing of electromagnetic (EM) waves has yielded many profound discoveries across fundamental physics, astronomy, astrophysics, and cosmology. Similar to EM waves, gravitational waves (GWs) can also be lensed. When their…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Zhao-Feng Wu , Otto A. Hannuksela , Martin Hendry , Quynh Lan Nguyen

A new type of objective lens has recently been proposed for use in X-ray photoemission electron microscopes (XPEEMs) and momentum microscopes. Adding a ring electrode concentric with the extractor allows the field in the gap between the…

Numerical studies on the imaging and caustic properties of the singular isothermal sphere (SIS) under a wide range of external shear (from 0.0 to 2.0) are presented. Using a direct inverse-mapping formula for this lens system (Lee 2003), we…

Astrophysics of Galaxies · Physics 2015-06-22 Dong-Wook Lee , Sang-Joon Kim

In this work we present a new method of black-box optimization and constraint satisfaction. Existing algorithms that have attempted to solve this problem are unable to consider multiple modes, and are not able to adapt to changes in…

Machine Learning · Computer Science 2020-02-19 Kourosh Hakhamaneshi , Keertana Settaluri , Pieter Abbeel , Vladimir Stojanovic

Gravitational lensing constitutes one of the most direct observational manifestations of spacetime curvature and provides a powerful probe of compact astrophysical objects. In this work, we present a comprehensive analysis of the bending of…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Partha Pratim Basumallick , Saheb Das , Bhaswati Mandal , Subhadip Sau

This study presents a prospective concept of a mechanically reconfigurable Gradient Index (GRIN) lens for focusing and beamforming applications. The lens is formed by corrugated layers, each realizing a refractive index profile expressed in…

Optics · Physics 2025-06-27 K. Kaboutari , X. Liu , A. Abraray , P. Pinho , S. Shen , S. Maslovski

GEneral Matrix Multiply (GEMM) is a central operation in deep learning and corresponds to the largest chunk of the compute footprint. Therefore, improving its efficiency is an active topic of ongoing research. A popular strategy is the use…

Machine Learning · Computer Science 2024-03-13 Zhanpeng Zeng , Karthikeyan Sankaralingam , Vikas Singh

Deconvolving COMPTEL gamma-ray data into images presents a major methodological challenge. We developed a new algorithm called Multiresolution Regularized Expectation Maximization (MREM), which explicitly accounts for spatial correlations…

Quantifying image distortions caused by strong gravitational lensing and estimating the corresponding matter distribution in lensing galaxies has been primarily performed by maximum likelihood modeling of observations. This is typically a…

Instrumentation and Methods for Astrophysics · Physics 2017-09-20 Yashar D. Hezaveh , Laurence Perreault Levasseur , Philip J. Marshall

In this letter, we present a novel low-complexity adaptive beamforming technique using a stochastic gradient algorithm to avoid matrix inversions. The proposed method exploits algorithms based on the maximum entropy power spectrum (MEPS) to…

Information Theory · Computer Science 2020-12-29 S. Mohammadzadeh , V. H. Nascimento , R. C. de Lamare

The Maximum Entropy Method (MEM) is a popular data analysis technique based on Bayesian inference, which has found various applications in the research literature. While the MEM itself is well-grounded in statistics, I argue that its…

Data Analysis, Statistics and Probability · Physics 2020-11-03 Alexander Rothkopf