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Future precision cosmology from large-scale structure experiments including the Dark Energy Spectroscopic Instrument (DESI) and Euclid will probe wider and deeper cosmic volumes than those covered by previous surveys. The Cartesian power…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-12 Mike Shengbo Wang , Santiago Avila , Davide Bianchi , Robert Crittenden , Will J. Percival

In this paper, we present an optimal filter for the enhancement or estimation of signals on the 2-sphere corrupted by noise, when both the signal and noise are realizations of anisotropic processes on the 2-sphere. The estimation of such a…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Zubair Khalid , Rodney A. Kennedy , Parastoo Sadeghi , Salman Durrani

Scattering amplitudes in quantum field theory are independent of the field parameterization, which has a natural geometric interpretation as a form of `coordinate invariance.' Amplitudes can be expressed in terms of Riemannian curvature…

High Energy Physics - Theory · Physics 2023-02-08 Timothy Cohen , Nathaniel Craig , Xiaochuan Lu , Dave Sutherland

We investigate invariant random fields on the sphere using a new type of spherical wavelets, called needlets. These are compactly supported in frequency and enjoy excellent localization properties in real space, with quasi-exponentially…

Statistics Theory · Mathematics 2009-09-29 P. Baldi , G. Kerkyacharian , D. Marinucci , D. Picard

We provide a computationally and statistically efficient method for estimating the parameters of a stochastic covariance model observed on a regular spatial grid in any number of dimensions. Our proposed method, which we call the Debiased…

Methodology · Statistics 2022-04-27 Arthur P. Guillaumin , Adam M. Sykulski , Sofia C. Olhede , Frederik J. Simons

We present a new deterministic algorithm for the sparse Fourier transform problem, in which we seek to identify k << N significant Fourier coefficients from a signal of bandwidth N. Previous deterministic algorithms exhibit quadratic…

Numerical Analysis · Mathematics 2012-07-27 David Lawlor , Yang Wang , Andrew Christlieb

This is a direct computation of the spectral representation of homogeneous spin-weighted spherical random fields with arbitrary integer spin. It generalises known results from Cosmology for the spin-2 Cosmic Microwave Background…

General Physics · Physics 2019-04-24 Nicolas Tessore

Several problems in computer algebra can be efficiently solved by reducing them to calculations over finite fields. In this paper, we describe an algorithm for the reconstruction of multivariate polynomials and rational functions from their…

High Energy Physics - Phenomenology · Physics 2016-12-14 Tiziano Peraro

We quantize the electromagnetic field in the presence of a nonmoving dielectric sphere in vacuum. The sphere is assumed to be lossless, dispersionless, isotropic, and homogeneous. The quantization is performed using normalized eigenmodes as…

Quantum Physics · Physics 2023-11-15 Patrick Maurer , Carlos Gonzalez-Ballestero , Oriol Romero-Isart

Spatial variables can be observed in many different forms, such as regularly sampled random fields (lattice data), point processes, and randomly sampled spatial processes. Joint analysis of such collections of observations is clearly…

Methodology · Statistics 2026-05-20 Jake P. Grainger , Tuomas A. Rajala , David J. Murrell , Sofia C. Olhede

We summarise the construction of exact axisymmetric scale-discretised wavelets on the sphere and on the ball. The wavelet transform on the ball relies on a novel 3D harmonic transform called the Fourier-Laguerre transform which combines the…

Information Theory · Computer Science 2013-01-28 Boris Leistedt , Jason D. McEwen

Neural networks have become ubiquitous with guitar distortion effects modelling in recent years. Despite their ability to yield perceptually convincing models, they are susceptible to frequency aliasing when driven by high frequency and…

Audio and Speech Processing · Electrical Eng. & Systems 2025-05-19 Alistair Carson , Alec Wright , Stefan Bilbao

This article introduces a method for estimating the smoothness of a stationary, isotropic Gaussian random field from irregularly spaced data. This involves novel constructions of higher-order quadratic variations and the establishment of…

Statistics Theory · Mathematics 2015-10-30 Wei-Liem Loh

We present a generalized frequency redistribution function for the polarized two-term atom in an arbitrary magnetic field. This result is derived within a new formulation of the quantum problem of coherent scattering of polarized radiation…

Solar and Stellar Astrophysics · Physics 2014-09-02 R. Casini , M. Landi Degl'Innocenti , R. Manso Sainz , E. Landi Degl'Innocenti , M. Landolfi

Spatial confounding is a fundamental issue in spatial regression models which arises because spatial random effects, included to approximate unmeasured spatial variation, are typically not independent of covariates in the model. This can…

Methodology · Statistics 2025-07-15 Emiko Dupont , Isa Marques , Thomas Kneib

The article discusses how the pattern of elastic scattering of an electron on a pair of identical atomic spheres will look if we abandon the standard in the molecular physics assumption that, outside the molecular sphere, in the external…

Atomic Physics · Physics 2022-09-20 A. S. Baltenkov , I. Woiciechowski

Suppose $L$ simultaneous independent stochastic systems generate observations, where the observations from each system depend on the underlying parameter of that system. The observations are unlabeled (anonymized), in the sense that an…

Signal Processing · Electrical Eng. & Systems 2022-09-01 Vikram Krishnamurthy

We present here an augmented space recursive technique in the k-representation which include diagonal, off-diagonal and the environmental disorder explicitly : an analytic, translationally invariant, multiple scattering theory for phonons…

Materials Science · Physics 2013-12-25 Aftab Alam , Abhijit Mookerjee

Holographic microscopy combined with forward modeling and inference allows colloidal particles to be characterized and tracked in three dimensions with high precision. However, current models ignore the effects of optical aberrations on…

Optics · Physics 2021-05-27 Caroline Martin , Brian Leahy , Vinothan Manoharan

We construct a non-perturbative approach based on quantum averaging combined with resonant transformations to detect the resonances of a given Hamiltonian and to treat them. This approach, that generalizes the rotating-wave approximation,…

Quantum Physics · Physics 2007-05-23 M. Amniat-Talab , S. Guerin , H. R. Jauslin