English
Related papers

Related papers: Nonlinear Fourier Analysis

200 papers

To investigate neural network parameters, it is easier to study the distribution of parameters than to study the parameters in each neuron. The ridgelet transform is a pseudo-inverse operator that maps a given function $f$ to the parameter…

Machine Learning · Computer Science 2024-04-22 Sho Sonoda , Isao Ishikawa , Masahiro Ikeda

The discrete Fourier transform (DFT) is an important operator which acts on the Hilbert space of complex valued functions on the ring Z/NZ. In the case where N=p is an odd prime number, we exhibit a canonical basis of eigenvectors for the…

Information Theory · Computer Science 2008-12-27 Shamgar Gurevich , Ronny Hadani

The Fourier transform is approximated over a finite domain using a Riemann sum. This Riemann sum is then expressed in terms of the discrete Fourier transform, which allows the sum to be computed with a fast Fourier transform algorithm more…

Numerical Analysis · Mathematics 2015-08-07 Jeremy Axelrod

This is a slightly edited version of the transparencies for a seminar at UCL, May 7, 2003. It is intended to give a quick view of background, ideas, and some calculations, in the applicatioon of some non commutative methods to algebraic…

Algebraic Topology · Mathematics 2007-05-23 Ronald Brown

We define and study a noncommutative Fourier transform on every homogeneous complex bounded domain. We then give an application in noncommutative differential geometry by defining noncommutative Baumslag-Solitar tori.

Functional Analysis · Mathematics 2016-01-28 Pierre Bieliavsky , Victor Gayral , Axel de Goursac , Florian Spinnler

A diagram approach to classical nonlinear stochastic field theory is introduced. This approach is intended to serve as a link between quantum and classical field theories, resulting in an independent constructive characterisation of the…

Statistical Mechanics · Physics 2007-05-23 L. I. Plimak , M. Fleischhauer , M. J. Collett , D. F. Walls

In this note we construct a quantum Fourier transform circuit in a recursive way, by directly copying the 'divide and conquer' construction of the fast Fourier transform algorithm, rather than using the explicit formula that is given in…

Quantum Physics · Physics 2007-05-23 Gloria Paradisi , Hugues Randriam

Integral transformations of the QCD invariant (running) coupling and of some related objects are discussed. Special attention is paid to the Fourier transformation, that is to transition from the space-time to the energy--momentum…

High Energy Physics - Theory · Physics 2007-05-23 D. V. Shirkov

This note gives a summary of ideas concerning Applied Fourier Analysis, mostly formulated for those who have to give such courses to engineers or mathematicians interested in real life applications. It tries to answer recurrent questions…

Functional Analysis · Mathematics 2024-10-10 Hans G. Feichtinger

We give estimates for the convolution product of an arbitrary number of endlessly continuable functions. This allows us to deal with nonlinear operations for the corresponding resurgent series, e.g. substitution into a convergent power…

Dynamical Systems · Mathematics 2016-09-07 Shingo Kamimoto , David Sauzin

Properties of the Cauchy-Riemann-Fueter equation for maps between quaternionic manifolds are studied. Spaces of solutions in case of maps from a K3-surface to the cotangent bundle of a complex projective space are computed. A relationship…

Differential Geometry · Mathematics 2008-05-30 Andriy Haydys

Potential algebras can be used effectively in the analysis of the quantum systems. In the article, we focus on the systems described by a separable, 2x2 matrix Hamiltonian of the first order in derivatives. We find integrals of motion of…

Mathematical Physics · Physics 2015-06-11 Vit Jakubsky

This paper presents a Carleman-Fourier linearization method for nonlinear dynamical systems with periodic vector fields involving multiple fundamental frequencies. By employing Fourier basis functions, the nonlinear dynamical system is…

Dynamical Systems · Mathematics 2024-11-19 Panpan Chen , Nader Motee , Qiyu Sun

The Moutard transformation for a two-dimensional Dirac operator with a complex-valued potential is constructed. It is showed that this transformation relates the potentials of Weierstrass representations of surfaces related by a composition…

Exactly Solvable and Integrable Systems · Physics 2017-12-19 R. M. Matuev , I. A. Taimanov

Nonlinear contraction theory is a comparatively recent dynamic control system design tool based on an exact differential analysis of convergence, in essence converting a nonlinear stability problem into a linear time-varying stability…

Pattern Formation and Solitons · Physics 2007-05-23 Winfried Lohmiller , Jean-Jacques E. Slotine

A spinor theory on a space with linear Lie type noncommutativity among spatial coordinates is presented. The model is based on the Fourier space corresponding to spatial coordinates, as this Fourier space is commutative. When the group is…

High Energy Physics - Theory · Physics 2012-08-14 A. Shariati , M. Khorrami , A. H. Fatollahi

This note presents a rigorous introduction to a selection of distributions along with their Fourier transforms, which are commonly encountered in signal processing and, in particular, magnetic resonance imaging (MRI). In contrast to many…

Functional Analysis · Mathematics 2025-06-24 Kaibo Tang

In this paper, we investigate the behavior of the Fourier transform on finite dimensional 2-step Lie groups and develop a general theory akin to that of the whole space or the torus. We provide a familiar framework in which computations are…

Classical Analysis and ODEs · Mathematics 2017-12-29 Guillaume Lévy

This is a survey on the use of Fourier transformation methods in the treatment of boundary problems for the fractional Laplacian $(-\Delta)^a$ (0<a<1), and pseudodifferential generalizations P, over a bounded open set $\Omega$ in $R^n$. The…

Analysis of PDEs · Mathematics 2025-03-10 Gerd Grubb

We defined a non-commutative algebra representation for quantum systems whose phase space is the cotangent bundle of the Lorentz group, and the non-commutative Fourier transform ensuring the unitary equivalence with the standard group…

High Energy Physics - Theory · Physics 2019-05-22 Daniele Oriti , Giacomo Rosati