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Related papers: Differentiable functions of quaternion variables

200 papers

We consider multiple lattices and functions defined on them. We introduce slow varying conditions for functions defined on the lattice and express the variation of a function in terms of an asymptotic expansion with respect to the slow…

Exactly Solvable and Integrable Systems · Physics 2009-11-11 D. Levi

We construct rich vector spaces of continuous functions with prescribed curved or linear pathwise quadratic variations. We also construct a class of functions whose quadratic variation may depend in a local and nonlinear way on the function…

Probability · Mathematics 2019-07-02 Yuliya Mishura , Alexander Schied

A new version of the Hadwiger theorem on convex functions is established and an explicit representation of functional intrinsic volumes is found using new functional Cauchy-Kubota formulas. In addition, connections between functional…

Functional Analysis · Mathematics 2025-07-28 Andrea Colesanti , Monika Ludwig , Fabian Mussnig

We prove quadratic estimates for complex perturbations of Dirac-type operators, and thereby show that such operators have a bounded functional calculus. As an application we show that spectral projections of the Hodge--Dirac operator on…

Spectral Theory · Mathematics 2009-11-10 Andreas Axelsson , Stephen Keith , Alan McIntosh

We derive sufficient conditions for the surjectivity of the Cauchy-Riemann operator $\overline{\partial}$ between spaces of weighted smooth Fr\'echet-valued functions. This is done by establishing an analog of H\"ormander's theorem on the…

Functional Analysis · Mathematics 2022-10-27 Karsten Kruse

We present a quaternion wavefunction formulation that reduces the incompressible Euler equations to a single nonlinear Schr\"odinger-type equation with a holomorphic constraint, revealing hidden geometric structure connecting quantum and…

Fluid Dynamics · Physics 2026-02-03 Farrukh A. Chishtie

This paper deals with some special integral transforms of Bargmann-Fock type in the setting of quaternionic valued slice hyperholomorphic and Cauchy-Fueter regular functions. The construction is based on the well-known Fueter mapping…

Complex Variables · Mathematics 2019-10-02 Kamal Diki , Rolf Sören Krausshar , Irene Sabadini

We show how Cauchy's Integral Formula and the ideas of Dunford's Holomorphic Functional Calculus (for unbounded operators) can be used to compute the Vacuum Characteristic Function (Quantum Fourier Transform) of quantum random variables…

Mathematical Physics · Physics 2024-07-08 Andreas Boukas

We develop a functional calculus for $d$-tuples of non-commuting elements in a Banach algebra. The functions we apply are free analytic functions, that is nc functions that are bounded on certain polynomial polyhedra.

Functional Analysis · Mathematics 2015-04-29 Jim Agler , John E. McCarthy

For the importance of differentiation theorems in metric spaces (starting with Pansu Rademacher type theorem in Carnot groups) and relations with rigidity of embeddings see the section 1.2 in Cheeger and Kleiner paper arXiv:math/0611954 and…

Metric Geometry · Mathematics 2009-11-25 Marius Buliga

The conception of C- and H-representations of any holomorphic function is further extended to the notions, definitions, lemmas and theorems of the complex integration. On this basis and the introduced notion of a H-plane, generalising the…

Complex Variables · Mathematics 2025-06-23 Michael Parfenov

Given n quaternions we investigate the extent of non-commutativity of their multiple products, commutators and exponential products.

Rings and Algebras · Mathematics 2007-05-23 N. Cohen , S. De Leo , G. Ducati

By observing that the fractional Caputo derivative can be expressed in terms of a multiplicative convolution operator, we introduce and study a class of such operators which also have the same self-similarity property as the Caputo…

Probability · Mathematics 2022-05-24 P. Patie , A. Srapionyan

We consider the fractional Schrodinger equation with a logarithmic nonlinearity, when the power of the Laplacian is between zero and one. We prove global existence results in three different functional spaces: the Sobolev space…

Analysis of PDEs · Mathematics 2024-04-11 Rémi Carles , Fangyuan Dong

For quaternionic signal processing algorithms, the gradients of a quaternion-valued function are required for gradient-based methods. Given the non-commutativity of quaternion algebra, the definition of the gradients is non-trivial. The HR…

Optimization and Control · Mathematics 2014-07-22 Mengdi Jiang , Yi Li , Wei Liu

We prove Noether-type theorems for fractional isoperimetric variational problems with Riemann-Liouville derivatives. Both Lagrangian and Hamiltonian formulations are obtained. Illustrative examples, in the fractional context of the calculus…

Optimization and Control · Mathematics 2013-07-09 Gastao S. F. Frederico , Delfim F. M. Torres

We prove a Nullstellensatz for the ring of polynomial functions in n non-commuting variables over Hamilton's ring of real quaternions. We also characterize the generalized polynomial identities in n variables which hold over the…

Rings and Algebras · Mathematics 2020-09-15 Gil Alon , Elad Paran

Noncommutative rational functions appeared in many contexts in system theory and control, from the theory of finite automata and formal languages to robust control and LMIs. We survey the construction of noncommutative rational functions,…

Rings and Algebras · Mathematics 2015-03-13 Dmitry S. Kaliuzhnyi-Verbovetskyi , Victor Vinnikov

We prove an analog of the quaternionic Borel-Pompieu formula in the sense of proportional fractional $\psi$-Cauchy-Riemann operators via Riemann-Liouville derivative with respect to another function.

Complex Variables · Mathematics 2023-08-29 José Oscar González-Cervantes , Isidro Paulino-Basurto , Juan Bory-Reyes

Estimates for the spectrum of the Cauchy operator and logarithms of solutions of non-autonomous differential equations in the space, expressed in an arbitrary matrix norm, are found. For equations with periodic coefficients, the lower bound…

Dynamical Systems · Mathematics 2014-12-16 Alexandr Zevin