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Discrete analogs of the index Whittaker transform are introduced and investigated. It involves series and integrals with respect to a second parameter of the Whittaker function $W_{\mu, {i n} }(x), \ x >0, \ \mu \in \mathbb{R}, \ n \in…

Classical Analysis and ODEs · Mathematics 2020-09-28 Semyon Yakubovich

We provide a coarse version of the relative index of Gromov and Lawson and thoroughly establish all of its basic properties. As an application, we discuss a general procedure to construct wrong way maps on the $K$-theory of the Roe algebra…

K-Theory and Homology · Mathematics 2025-06-18 Alexander Engel , Christopher Wulff

Graded rings provide a natural algebraic framework for encoding symmetry via decompositions into homogeneous components indexed by a group, together with multiplication rules reflecting the group operation. Among graded rings, strongly…

Rings and Algebras · Mathematics 2026-05-12 Joakim Arnlind , Stefan Wagner

Analogous to subfactor theory, employing Watatani's notions of index and $C^*$-basic construction of certain inclusions of $C^*$-algebras, (a) we develop a Fourier theory (consisting of Fourier transforms, rotation maps and shift operators)…

Operator Algebras · Mathematics 2026-01-01 Keshab Chandra Bakshi , Ved Prakash Gupta

We discuss the possibility of very regular subgroups of a Lie group, in presence of an index figure. Further, representations that reduce action to a very regular boundary.

Analysis of PDEs · Mathematics 2024-02-19 T. Dahn

For a Lie groupoid there is an analytic index morphism which takes values in the $K-$theory of the $C^*$-algebra associated to the groupoid. This is a good invariant but extracting numerical invariants from it, with the existent tools, is…

K-Theory and Homology · Mathematics 2007-05-23 Paulo Carrillo Rouse

In this work we investigate the representation of counterfactual conditionals using the vector logic, a matrix-vectors formalism for logical functions and truth values. Inside this formalism, the counterfactuals can be transformed in…

Computation and Language · Computer Science 2020-09-03 Eduardo Mizraji

We show that a free product of a II_1-factor and a finite von Neumann algebra with amalgamation over a finite dimensional subalgebra is always a II_1-factor, and provide an algorithm for describing it in terms of free products (with…

Operator Algebras · Mathematics 2010-02-10 Ken Dykema

A novel algebra underlying integrable systems is shown to generate and unify a large class of quantum integrable models with given $R$-matrix, through reductions of an ancestor Lax operator and its different realizations. Along with known…

High Energy Physics - Theory · Physics 2009-10-31 Anjan Kundu

The paper introduces in a new although maybe unusual form the examples of types provided by J. von Neumann and F.J. Murray in their outstanding papers on algebraic factorization (1936-1943)pursuing three main aims: speculating about the…

Mathematical Physics · Physics 2008-09-12 Renato Nobili

An automated treatment of iterated integrals based on letters induced by real-valued quadratic forms and Kummer--Poincar\'e letters is presented. These quantities emerge in analytic single and multi--scale Feynman diagram calculations. To…

High Energy Physics - Theory · Physics 2021-06-02 J. Ablinger , J. Blümlein , C. Schneider

For any given integer $n\geq 1$, we construct i.c.c. groups $G$ such that the II$_1$ factors $L(G)$ have exactly $n$-many $G$-invariant von Neumann subalgebras not arising from subgroups.

Operator Algebras · Mathematics 2026-05-05 Yongle Jiang , Qinxuan Xu

We consider matrix functions with certain invariance under inversion in the unit circle. If such a function satisfies a positivity assumption on the unit circle, then only zero partial indices appear in its Riemann-Hilbert (Wiener-Hopf)…

Mathematical Physics · Physics 2018-06-01 Hideshi Yamane

Index maps taking values in the $K$-theory of a mapping cone are defined and discussed. The resulting index theorem can be viewed in analogy with the Freed-Melrose index theorem. The framework of geometric $K$-homology is used in a…

K-Theory and Homology · Mathematics 2016-03-11 Robin J. Deeley

A subtheory of a quantum field theory specifies von~Neumann subalgebras $\aa(\oo)$ (the `observables' in the space-time region $\oo$) of the von~Neumann algebras $\bb(\oo)$ (the `fields' localized in $\oo$). Every local algebra being a…

High Energy Physics - Theory · Physics 2010-11-01 R. Longo , K. -H. Rehren

Preliminary version of a book on univariate real analysis, with 14 chapters and 2 appendices. 1. Real numbers; 2. Limits of real sequences; 3. Series; 4. Limits of real functions. 5. Elementary functions; 6. Continuous functions; 7.…

History and Overview · Mathematics 2026-04-20 Martin Klazar

The usual nonnegative modulus function is based on addition. A natural different modulus function on the set of positive reals is introduced. Arguments for results for series through the usual modulus function are transformed to arguments…

General Mathematics · Mathematics 2019-12-10 C. Ganesa Moorthy

For certain problems involving vector fields, it is possible to find an associated imaginary field that, in conjunction with the first, forms a complex field for which the equation can be solved. This result is generalized to arbitrary…

Differential Geometry · Mathematics 2007-05-23 Dennis Hou

Thevon Neumann entropy, named after John von Neumann, is an extension of the classical concept of entropy to the field of quantum mechanics. From a numerical perspective, von Neumann entropy can be computed simply by computing all…

Information Theory · Computer Science 2020-02-04 Eugenia-Maria Kontopoulou , Gregory-Paul Dexter , Wojciech Szpankowski , Ananth Grama , Petros Drineas

Factor analysis aims to describe high dimensional random vectors by means of a small number of unknown common factors. In mathematical terms, it is required to decompose the covariance matrix $\Sigma$ of the random vector as the sum of a…

Optimization and Control · Mathematics 2017-08-02 Valentina Ciccone , Augusto Ferrante , Mattia Zorzi