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The super-parametric density estimators and its related algorism were suggested by Y. -S. Tsai et al [7]. The number of parameters is unlimited in the super- parametric estimators and it is a general theory in sense of unifying or…

Computation · Statistics 2008-11-07 Yeong-Shyeong Tsai , Ying-Lin Hsu , Mung-Chung Shung

We study gravitational lensing by compact objects in gravity theories that can be written in a Post-Post-Newtonian (PPN) framework: i.e., the metric is static and spherically symmetric, and can be written as a Taylor series in m/r, where m…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Charles R. Keeton , A. O. Petters

Most transit microlensing events due to very low-mass lens objects suffer from extreme finite-source effects. While modeling their light curves, there is a known continuous degeneracy between their relevant lensing parameters, i.e., the…

Instrumentation and Methods for Astrophysics · Physics 2023-04-20 Sedighe Sajadian

We introduce a new adaptive and fully Bayesian grid-based method to model strong gravitational lenses with extended images. The primary goal of this method is to quantify the level of luminous and dark-mass substructure in massive galaxies,…

Astrophysics · Physics 2009-11-13 S. Vegetti , L. V. E. Koopmans

f(R) gravity is thought to be an alternative to dark energy which can explain the acceleration of the universe. It has been tested by different observations including type Ia supernovae (SNIa), the cosmic microwave background (CMB), the…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-12 Kai Liao , Zong-Hong Zhu

Strong field gravitational lensing in the Brans-Dicke theory has been studied. The deflection angle for photons passing very close to the photon sphere is estimated for the static spherically symmetric space-time of the theory and the…

General Relativity and Quantum Cosmology · Physics 2024-01-02 Kabita Sarkar , Arunava Bhadra

In this paper we apply the strong deflection limit approach to investigate the gravitational lensing phenomena beyond general relativity. This is accomplished by considering the lensing effects related to black hole solutions that emerge…

General Relativity and Quantum Cosmology · Physics 2016-10-13 R. T. Cavalcanti , A. Goncalves da Silva , Roldao da Rocha

We experimentally demonstrate the simultaneous estimation of the three parameters characterizing a pair of incoherent optical sources in the sub-Rayleigh regime, enabling super-resolved scene characterization. Using spatial-mode…

We investigate the use of approximate Bayesian neural networks (BNNs) in modeling hundreds of time-delay gravitational lenses for Hubble constant ($H_0$) determination. Our BNN was trained on synthetic HST-quality images of strongly lensed…

Instrumentation and Methods for Astrophysics · Physics 2021-04-13 Ji Won Park , Sebastian Wagner-Carena , Simon Birrer , Philip J. Marshall , Joshua Yao-Yu Lin , Aaron Roodman

We present a framework that reformulates gravitational lensing as an optical phenomenon governed by an effective refractive index, enabling exploration of modified gravity theories using undergraduate-level mathematics and optics. After…

General Relativity and Quantum Cosmology · Physics 2026-04-09 Romy Hanang Setya Budhi

The error propagation among estimated parameters reflects the correlation among the parameters. We study the capability of machine learning of "learning" the correlation of estimated parameters. We show that machine learning can recover the…

Astrophysics of Galaxies · Physics 2024-01-10 Xilong Fan , Peizheng Wang , Jin Li , Nan Yang

We present new mass models for the gravitational lens system B1938+666, using multi-wavelength data acquired from Keck adaptive optics (AO) and Hubble Space Telescope (HST) observations. These models are the first results from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 D. J. Lagattuta , S. Vegetti , C. D. Fassnacht , M. W. Auger , L. V. E. Koopmans , J. P. McKean

We establish sharp estimates for the convergence rate of the Kranosel'ski\v{\i}-Mann fixed point iteration in general normed spaces, and we use them to show that the asymptotic regularity bound recently proved in [11] (Israel Journal of…

Optimization and Control · Mathematics 2017-01-31 Mario Bravo , Roberto Cominetti

The rational camera model recently introduced in [19] provides a general methodology for studying abstract nonlinear imaging systems and their multi-view geometry. This paper builds on this framework to study "physical realizations" of…

Computer Vision and Pattern Recognition · Computer Science 2017-04-12 Matthew Trager , Bernd Sturmfels , John Canny , Martial Hebert , Jean Ponce

Strong gravitational lensing of gravitational waves (GWs) occurs when the GWs from a compact binary system travel near a massive object. The mismatch between a lensed signal and unlensed templates determines whether lensing can be…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Saif Ali , Evangelos Stoikos , Evan Meade , Michael Kesden , Lindsay King

Gravitational lensing of luminous matter that surrounds a black hole or some other sufficiently compact object produces an infinite sequence of images. Besides the direct (or primary) image, it comprises demagnified and deformed replicas of…

General Relativity and Quantum Cosmology · Physics 2024-08-21 Fabio Aratore , Oleg Yu. Tsupko , Volker Perlick

Deep neural networks (DNN) are versatile parametric models utilised successfully in a diverse number of tasks and domains. However, they have limitations---particularly from their lack of robustness and over-sensitivity to out of…

Machine Learning · Statistics 2020-01-01 John Mitros , Brian Mac Namee

Classifiers built with neural networks handle large-scale high dimensional data, such as facial images from computer vision, extremely well while traditional statistical methods often fail miserably. In this paper, we attempt to understand…

Machine Learning · Statistics 2020-02-04 Tianyang Hu , Zuofeng Shang , Guang Cheng

We discuss the wave optical effects in gravitational lens systems with two point mass lenses in two different lens planes. We identify and vary parameters (i.e., lens masses, related distances, and their alignments) related to the lens…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-06 Rahul Ramesh , Ashish Kumar Meena , J S Bagla

Gravitational lensing is the deflection of light rays due to the gravity of intervening masses. This phenomenon is observed in a variety of scales and configurations, involving any non-uniform mass such as planets, stars, galaxies, clusters…

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