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We propose an experiment using a conventional optical telescope to determine whether aberration of starlight results from special relativistic effects external to a measurement sensor or from optical effects within a sensor. The proposed…

Instrumentation and Methods for Astrophysics · Physics 2013-07-30 Robert A. Woodruff

It is generally thought that correcting chromatic aberrations in imaging requires multiple surfaces. Here, we show that by allowing the phase in the image plane of a flat lens to be a free parameter, it is possible to correct chromatic…

We explore the applications of machine learning techniques in relativistic laser-plasma experiments beyond optimization purposes. We predict the beam charge of electrons produced in a laser wakefield accelerator given the laser wavefront…

Analog beamforming holds great potential for future terahertz (THz) communications due to its ability to generate high-gain directional beams with low-cost phase shifters. However, conventional analog beamforming may suffer substantial…

Signal Processing · Electrical Eng. & Systems 2026-03-26 Yike Xie , Weidong Mei , Dong Wang , Yingqi Wen , Zhi Chen , Jun Fang , Wei Guo , Boyu Ning

We propose a practical method to calculate Zernike aberrations from analysis of a single long-exposure defocused stellar image. It consists in fitting the aberration coefficients and seeing blur directly to a realistic image binned into…

Astrophysics · Physics 2009-11-11 A. Tokovinin , S. Heathcote

LINC-NIRVANA will realize the interferometric imaging focal station of the Large Binocular Telescope. A double Layer Oriented multi-conjugate adaptive optics system assists the two arms of the interferometer, supplying high order wave-front…

In astronomy or biological imaging, refractive index inhomogeneities of e.g. atmosphere or tissues induce optical aberrations which degrade the desired information hidden behind the medium. A standard approach consists in measuring these…

Optics · Physics 2023-06-01 Tengfei Wu , Marc Guillon , Gilles Tessier , Pascal Berto

The main disadvantage of Magnetic Resonance Imaging (MRI) are its long scan times and, in consequence, its sensitivity to motion. Exploiting the complementary information from multiple receive coils, parallel imaging is able to recover…

Numerical Analysis · Computer Science 2017-03-07 Martin Uecker

A random-matrix theory is presented for the reflection of light by a disordered medium backed by a phase-conjugating mirror. Two regimes are distinguished, depending on the relative magnitude of the inverse dwell time of a photon in the…

Condensed Matter · Physics 2007-05-23 J. C. J. Paasschens , P. W. Brouwer , C. W. J. Beenakker

Point Spread Function (PSF) for imaging through inhomogeneous refractive medium, such as atmospheric turbulence is bounded by three constraints [Charnotskii, Opt. Eng., 52, 04600, (2013)]. PSF is non-negative, band-limited, and the third…

Optics · Physics 2022-07-06 Mikhail Charnotskii

We construct supersymmetric deformations of general, locally supersymmetric, nonlinear sigma models in three spacetime dimensions, by extending the pure supergravity theory with a Chern-Simons term and gauging a subgroup of the sigma model…

High Energy Physics - Theory · Physics 2010-04-05 Bernard de Wit , Ivan Herger , Henning Samtleben

For a theory with first and second class constraints, we propose a procedure for conversion of second class constraints based on deformation the structure of local symmetries of the Lagrangian formulation. It does not require extension or…

High Energy Physics - Theory · Physics 2008-11-26 A. A. Deriglazov , Z. Kuznetsova

There are a number of approaches to testing General Relativity (GR) on linear scales using parameterized frameworks for modifying cosmological perturbation theory. It is sometimes assumed that the details of any given parameterization are…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Joe Zuntz , Tessa Baker , Pedro Ferreira , Constantinos Skordis

We analyse the origin of the Adler anomaly of chiral U(1) gauge theory within the framework of regularized path integrals. Momentum or position space regulators allow for mathematically well-defined path integrals but violate local gauge…

Mathematical Physics · Physics 2015-06-03 Christoph Kopper , Benjamin Lévêque

Unbiased estimators are introduced for averaged Bregman divergences which generalize Stein's Unbiased (Predictive) Risk Estimator, and the minimization of these estimators is proposed as a regularization parameter selection method for…

Numerical Analysis · Mathematics 2021-11-22 Elias S. Helou , Sandra A. Santos , Lucas E. A. Simões

Nondestructive spin-resolved imaging of ultracold atomic gases requires calculating the differences of the refractive indices seen by two circular probe polarizations. Perfect overlap of the two images, corresponding to two different…

Quantum Gases · Physics 2025-11-05 Nejc Blaznik , Dries van Oosten , Peter van der Straten

Light beams can be symmetric under different transformations: translations, rotations, mirror symmetries, duality transformations, etc. In this thesis, a systematic way of characterizing these symmetries is presented. Then, it is shown that…

Optics · Physics 2016-11-03 Xavier Zambrana-Puyalto

Future Extremely Large Telescopes will adopt segmented primary mirrors with several hundreds of segments. Cophasing of the segments together is essential to reach high wavefront quality. The phasing sensor must be able to maintain very high…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Arthur Vigan , Kjetil Dohlen , Silvio Mazzanti

We construct Z_M, M= 2, 3, 4, 6 orbifold models of the N=2 superconformal field theories with central charge c=3. Then we check the description of the Z_3, Z_4 and Z_6 orbifolds by the N=2 superconformal Landau-Ginzburg models with c=3, by…

High Energy Physics - Theory · Physics 2008-11-26 Sayipjamal Dulat

Three-dimensional N=2 superconformal field theories are constructed by compactifying M5-branes on three-manifolds. In the infrared the branes recombine, and the physics is captured by a single M5-brane on a branched cover of the original…

High Energy Physics - Theory · Physics 2012-11-16 Clay Cordova , Sam Espahbodi , Babak Haghighat , Ashwin Rastogi , Cumrun Vafa
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