Results 61 to 70 of about 6,188,577 (200)

Risk Measure Duality Without Structure

Mathematical Finance, EarlyView.
ABSTRACT We study risk measures on vector spaces of random variables which a priori have little structure, such as spaces lacking law invariance or a lattice structure. Ensuring the existence of a tractable dual representation (one which does not contain non‐sigma‐additive measures) is one of the main problems in risk measure theory, and we address it ...
Vasily Melnikov
wiley   +1 more source

CHAOTIC AND HYPERCYCLIC OPERATORS ON SOLID BANACH FUNCTION SPACES

Проблемы анализа, 2020
In this paper, we study hypercyclicity on solid Banach function spaces, and give the characterization for weighted translation operators to be hypercyclic in terms of weight and aperiodic functions.
C-C. Chen, S. M. Tabatabaie
doaj   +1 more source

Gradient Systems and Scale‐Aware Heat Equations

Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 4, December 2026.
ABSTRACT The extreme miniaturization of modern microelectronic architectures exposes the limitations of classical continuum mechanics, as Fourier's law breaks down at sub‐micron scales (100–0.1 μm$\umu{\rm m}$). While molecular models can accurately capture these thermal flow regimes, they remain computationally expensive.
Grigor Nika
wiley   +1 more source

Monotonicity in Modular Function Spaces Equipped with O-norm

Journal of Harbin University of Science and Technology
Modular function spaces are extensions of Lebesgue spaces and Orlicz spaces. We introduce Orlicz norm in Modular function spaces, and study the monotonicity in modular function spaces equipped with O-norm and L-norm.
HU Xuemei, CUI Yunan
doaj   +1 more source

Toeplitz Operators on Abstract Hardy Spaces Built upon Banach Function Spaces

Journal of Function Spaces, 2017
Let X be a Banach function space over the unit circle T and let H[X] be the abstract Hardy space built upon X. If the Riesz projection P is bounded on X and a∈L∞, then the Toeplitz operator Taf=P(af) is bounded on H[X].
Alexei Yu. Karlovich
doaj   +1 more source

Inverse problems for semilinear elliptic PDE with a general nonlinearity a(x,u)$a(x,u)$

Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract This article studies the inverse problem of recovering a nonlinearity in an elliptic equation Δu+a(x,u)=0$\Delta u + a(x,u) = 0$ from boundary measurements of solutions. Previous results based on first‐order linearization achieve this under a sign condition on ∂ua(x,u)$\partial _u a(x,u)$, and results based on higher order linearization ...
David Johansson, Janne Nurminen, Mikko Salo   +2 more
wiley   +1 more source

New Sequence Spaces and Function Spaces on Interval [0,1]

Journal of Function Spaces and Applications, 2013
We study the sequence spaces and the spaces of functions defined on interval 0,1 in this paper. By a new summation method of sequences, we find out some new sequence spaces that are interpolating into spaces between ℓp and ℓq and function spaces that are
Cheng-Zhong Xu, Gen-Qi Xu
doaj   +1 more source

On the Existence of Solutions of Dynamic Equations on Time Scales in Banach Spaces

Mathematical Methods in the Applied Sciences, Volume 49, Issue 13, Page 15358-15384, 15 September 2026.
ABSTRACT In this paper we address the question of solvability of dynamic equations on time scales in Banach spaces. In particular, our main theorem extends the result for classical differential equations in Banach spaces of Banaś and Goebel established in [5], to an arbitrary time scale.
Dušan Oberta
wiley   +1 more source

Amenability Constants for Unconditional Sums of Banach Algebras

Mathematische Nachrichten, Volume 299, Issue 9, Page 2472-2494, September 2026.
ABSTRACT We study Johnson amenability for unconditional direct sums of Banach algebras. Given a family (Ai)i∈I$(A_i)_{i\in I}$ of Banach algebras and a Banach sequence lattice E$E$ on I$I$, the E$E$‐sum ⨁i∈IAiE${\bigl (\bigoplus _{i\in I} A_i\bigr)}_{\!E}$ carries a natural Banach algebra structure via coordinatewise multiplication.
Tomasz Kania, Jerzy Ka̧kol
wiley   +1 more source

Rothe Time Discretization and Weak Solutions for a Cutoff Westervelt System

Numerical Methods for Partial Differential Equations, Volume 42, Issue 5, September 2026.
ABSTRACTWe study a fully implicit Rothe time discretization for a cutoff first‐order formulation of the Westervelt equation. The key ingredients are the enthalpy variable and the primitive mobility variable, which turn each nonlinear time step into a uniformly monotone elliptic problem and avoid higher‐order energy estimates and inverse inequalities ...
Marvin Fritz
wiley   +1 more source