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Related papers: Aperiodic order and pure point diffraction

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We present a simplified model for dynamical diffraction of particles through a periodic thick perfect crystal based on repeated application of a coherent beam splitting unitary at coarse-grained lattice sites. By demanding translational…

Quantum Physics · Physics 2016-12-14 J. Nsofini , K. Ghofrani , D. Sarenac , D. G. Cory , D. A. Pushin

We show that for multi-colored Delone point sets with finite local complexity and uniform cluster frequencies the notions of pure point diffraction and pure point dynamical spectrum are equivalent.

Dynamical Systems · Mathematics 2009-10-27 Jeong-Yup Lee , Robert V. Moody , Boris Solomyak

When considering fractional diffusion equation as model equation in analyzing anomalous diffusion processes, some important parameters in the model, for example, the orders of the fractional derivative or the source term, are often unknown,…

Analysis of PDEs · Mathematics 2019-04-15 Zhiyuan Li , Masahiro Yamamoto

In this paper, we describe the general framework to describe the diffusion operators associated to a positive matrix. We define the equations associated to diffusion operators and present some general properties of their state vectors. We…

Numerical Analysis · Mathematics 2012-06-19 Dohy Hong , Gérard Burnside

In a recent paper, Lenz and Moody (arXiv:1111.3617) presented a method for constructing families of real solutions to the inverse problem for a given pure point diffraction measure. Applying their technique and discussing some possible…

Spectral Theory · Mathematics 2012-10-15 Venta Terauds , Michael Baake

Geometry arising from two diffusion operators (smooth semi-elliptic, second order differential operators) on different spaces but intertwined by a smooth map is described. Particular cases arise from Riemannian submersions when the…

Differential Geometry · Mathematics 2016-07-22 K. D. Elworthy , Y. LeJan , Xue-Mei Li

We define spherical diffraction measures for a wide class of weighted point sets in commutative spaces, i.e. proper homogeneous spaces associated with Gelfand pairs. In the case of the hyperbolic plane we can interpret the spherical…

Dynamical Systems · Mathematics 2020-02-14 Michael Björklund , Tobias Hartnick , Felix Pogorzelski

In pseudo integrable systems diffractive scattering caused by wedges and impurities can be described within the framework of Geometric Theory of Diffraction (GDT) in a way similar to the one used in the Periodic Orbit Theory of Diffraction…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 G. Vattay , J. Cserti , G. Palla , G. Szálka

We consider the problem of reconstructing the paths of a set of points over time, where, at each of a finite set of moments in time the current positions of points in space are only accessible through some small number of their X-rays. This…

Data Structures and Algorithms · Computer Science 2018-11-08 Andreas Alpers , Peter Gritzmann

The inverse problem of diffraction theory in essence amounts to the reconstruction of the atomic positions of a solid from its diffraction image. From a mathematical perspective, this is a notoriously difficult problem, even in the…

Metric Geometry · Mathematics 2009-02-23 Uwe Grimm , Michael Baake

Results on soft and hard diffraction are briefly reviewed with emphasis on the interplay among factorization properties, universality of rapidity gap formation and unitarity.

High Energy Physics - Phenomenology · Physics 2014-11-17 Konstantin Goulianos

We study the diffusion front for a natural two-dimensional model where many particles starting at the origin diffuse independently. It turns out that this model can be described using properties of near-critical percolation, and provides a…

Probability · Mathematics 2009-12-21 Pierre Nolin

The chapter contains a detailed presentation of the surface integral theory for modelling light diffraction by surface-relief diffraction gratings having a one-dimensional periodicity. Several different approaches are presented, leading…

Optics · Physics 2014-06-03 Daniel Maystre , Evgeny Popov

At present, the theory of light diffraction only has the simple wave-optical approach. In this paper, we study light diffraction with the approach of relativistic quantum theory. We find that the slit length, slit width, slit thickness and…

We describe the mathematical theory of diffusion and heat transport with a view to including some of the main directions of recent research. The linear heat equation is the basic mathematical model that has been thoroughly studied in the…

Analysis of PDEs · Mathematics 2017-06-27 Juan Luis Vázquez

In the recent years, mater-wave interferometry has attracted growing attention due to its unique suitability for high-precision measurements and study of fundamental aspects of quantum theory. Diffraction and interference of matter waves…

Quantum Physics · Physics 2013-05-30 Arseni Goussev

Diffusion and flow-based models have become the state of the art for generative AI across a wide range of data modalities, including images, videos, shapes, molecules, music, and more. This tutorial provides a self-contained introduction to…

Machine Learning · Computer Science 2026-03-19 Peter Holderrieth , Ezra Erives

Conventional finite-difference schemes for solving partial differential equations are based on approximating derivatives by finite-differences. In this work, an alternative theory is proposed which view finite-difference schemes as…

Numerical Analysis · Mathematics 2013-09-23 Siu A. Chin

The set of points of a one-dimensional cut-and-project quasicrystal or model set, while not additive, is shown to be multiplicative for appropriate choices of acceptance windows. This leads to the definition of an associative additive…

Mathematical Physics · Physics 2009-10-02 David B. Fairlie , Reidun Twarock , Cosmas K. Zachos

In this paper, we define the general framework to describe the diffusion operators associated to a positive matrix. We define the equations associated to diffusion operators and present some general properties of their state vectors. We…

Numerical Analysis · Computer Science 2013-01-15 Dohy Hong , Fabien Mathieu , Gérard Burnside