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We construct reflection functors on categories of modules over deformed wreath products of the preprojective algebra of a quiver. These functors give equivalences of categories associated to generic parameters which are in the same orbit…

Representation Theory · Mathematics 2007-05-23 Wee Liang Gan

The Weyl anomaly in the Holographic Renormalisation Group as implemented using Hamilton-Jacobi language is studied in detail. We investigate the breakdown of the descent equations in order to isolate the Weyl anomaly of the dual field…

High Energy Physics - Theory · Physics 2010-02-03 Jussi Kalkkinen , Dario Martelli , Wolfgang Mueck

Let $G$ be a reductive group with Borel $B$ and Weyl group $W$. Then $B$-double cosets in $G$ are indexed by the Weyl group, say $O(w)$ for $w\in W$. Then we prove the minimal $B$-double coset in the convolution $O(w_1)*O(w_2)$ is…

Representation Theory · Mathematics 2025-03-26 Kenta Suzuki

The Fractional Fourier Transform is a ubiquitous signal processing tool in basic and applied sciences. The Fractional Fourier Transform generalizes every property and application of the Fourier Transform. Despite the practical importance of…

Signal Processing · Electrical Eng. & Systems 2020-10-21 Amir R. Nafchi , Eric Hamke , Cristina Pereyra , Ramiro Jordan

We consider the notion of a confluent spherical function on a connected semisimple Lie group, $G,$ with finite center and of real rank $1,$ and discuss the properties and relationship of its algebra with the well-known Schwartz algebra of…

Representation Theory · Mathematics 2017-07-04 Olufemi O. Oyadare

This work shows the use of a two-dimensional Gabor wavelets in image processing. Convolution with such a two-dimensional wavelet can be separated into two series of one-dimensional ones. The key idea of this work is to utilize a Gabor…

Computer Vision and Pattern Recognition · Computer Science 2016-05-05 David Barina

We study the algebra of functions on the Iwahori group via the category of graded bounded representations of its Lie algebra. In particular, we identify the standard and costandard objects in this category with certain generalized Weyl…

Representation Theory · Mathematics 2025-03-13 Evgeny Feigin , Anton Khoroshkin , Ievgen Makedonskyi , Daniel Orr

We describe the action of the Weyl group of a semi simple linear group $G$ on cohomological and K-theoretic invariants of the generalized flag variety $G/B$. We study the automorphism $s_i$, induced by the reflection in the simple root, on…

Algebraic Geometry · Mathematics 2024-05-28 Mieszko Baszczak

In this paper we generalize previous work on decomposition in three-dimensional orbifolds by 2-groups realized as analogues of central extensions, to orbifolds by more general 2-groups. We describe the computation of such orbifolds in…

High Energy Physics - Theory · Physics 2023-08-23 Alonso Perez-Lona , Eric Sharpe

This work presents a method of computing Voigt functions and their derivatives, to high accuracy, on a uniform grid. It is based on an adaptation of Fourier-transform based convolution. The relative error of the result decreases as the…

Data Analysis, Statistics and Probability · Physics 2007-05-23 Marcus H. Mendenhall

Derived from the results in [Giang et al.: \emph{Convolutions for the Fourier transforms with geometric variables and applications}, Math. Nachr. 283(12) (2010), 1758--1770], in this paper, we devoted to studying the boundedness properties…

Classical Analysis and ODEs · Mathematics 2025-08-12 Nguyen Thi Hong Phuong , Trinh Tuan , Lai Tien Minh

Random walk on the chambers of hyperplanes arrangements is used to define a family of card shuffling measures $H_{W,x}$ for a finite Coxeter group W and real $x \neq 0$. By algebraic group theory, there is a map from the semisimple orbits…

Group Theory · Mathematics 2007-05-23 Jason Fulman

A {\em cyclic graph} is a graph with at each vertex a cyclic order of the edges incident with it specified. We characterize which real-valued functions on the collection of cubic cyclic graphs are partition functions of a real vertex model…

Quantum Algebra · Mathematics 2016-08-02 Guus Regts , Alexander Schrijver , Bart Sevenster

In 1962, Bienenstock and Ewald described the classification of crystalline space groups algebraically in the dual, or Fourier, space. Recently, the method has been applied to quasicrystals and modulated crystals. This paper phrases…

Mathematical Physics · Physics 2007-05-23 Benji N. Fisher , David A. Rabson

The W-set of an element of a weak order poset is useful in the cohomological study of the closures of spherical subgroups in generalized flag varieties. We explicitly describe in a purely combinatorial manner the W-sets of the weak order…

Combinatorics · Mathematics 2014-09-16 Mahir Bilen Can , Michael Joyce , Benjamin Wyser

Polynomial invariants are fundamental objects in analysis on Lie groups and symmetric spaces. Invariant differential operators on symmetric spaces are described by Weyl group invariant polynomial. In this article we give a simple criterion…

Representation Theory · Mathematics 2010-12-06 Gestur Olafsson , Joseph A. Wolf

The cone-beam transform consists of integrating a function defined on the three-dimensional space along every ray that starts on a certain scanning set. Based on Grangeat's formula, Louis [2016, Inverse Problems 32 115005] states…

Numerical Analysis · Mathematics 2021-08-13 Michael Quellmalz , Ralf Hielscher , Alfred K. Louis

In this note we explore the relationship between the operation of convolution of functions and the Eulerian integrals. This approach allow us to obtain some expressions for the convolution of a certain class of functions in terms of the…

History and Overview · Mathematics 2024-02-27 Francisco Mota

Clifford theory relates the representation theory of finite groups to those of a fixed normal subgroup by means of induction and restriction, which is an adjoint pair of functors. We generalize this result to the situation of a…

Representation Theory · Mathematics 2023-01-27 Alexander Zimmermann

In this thesis we give a construction of cyclic cocycles on convolution algebras twisted by gerbes over discrete translation groupoids. In his seminal book, Connes constructs a map from the equivariant cohomology of a manifold carrying the…

Quantum Algebra · Mathematics 2010-10-01 Eitan Angel