Results 1 to 10 of about 376 (89)
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
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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
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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
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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
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Adaptive Estimation for Weakly Dependent Functional Times Series
Journal of Time Series Analysis, Volume 47, Issue 5, Page 1013-1027, September 2026.ABSTRACT We propose adaptive mean and autocovariance function estimators for stationary functional time series under 𝕃p−m‐approximability assumptions. These estimators are designed to adapt to the regularity of the curves and to accommodate both sparse and dense data designs.
Hassan Maissoro +2 more
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Metric spaces with small rough angles and the rectifiability of rough self‐contracted curves
Journal of the London Mathematical Society, Volume 114, Issue 3, September 2026.Abstract The small rough angle (SRA$\operatorname{SRA}$) condition, introduced by Zolotov in arXiv:1804.00234, captures the idea that all angles formed by triples of points in a metric space are small. In the first part of the paper, we develop the theory of metric spaces (X,d)$(X,d)$ satisfying the SRA(α)$\operatorname{SRA}(\alpha)$ condition for some
Estibalitz Durand Cartagena +1 more
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Well‐posedness of heat equations with nonlinearities of arbitrarily rapid growth
Proceedings of the London Mathematical Society, Volume 133, Issue 3, September 2026.Abstract We address local‐ and global‐in‐time well‐posedness of the Cauchy problem for nonlinear heat equations without imposing growth rate restrictions on the nonlinearity a priori. Our results constitute a nontrivial expansion of the classical Lq$L^q$‐theory for nonlinearities dominated by polynomial growth and the exponential‐Orlicz space theory ...
Yohei Fujishima +2 more
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Mathematical Methods in the Applied Sciences, Volume 49, Issue 12, Page 14122-14148, August 2026.ABSTRACT This paper develops a mathematical framework for interpreting observations of solar inertial waves in an idealized setting. Under the assumption of purely toroidal linear waves on the sphere, the stream function of the flow satisfies a fourth‐order scalar equation.
Tram Thi Ngoc Nguyen +3 more
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International Journal for Numerical and Analytical Methods in Geomechanics, Volume 50, Issue 12, Page 4879-4892, 25 August 2026.ABSTRACT This work presents a general framework for deriving the Young–Laplace equation and the Young's equations for an axisymmetric capillary bridge between two parallel plates by minimizing the system's total energy. These Young's equations naturally emerge as boundary conditions associated with the Young–Laplace equation.
Olivier Millet +3 more
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A Unified Framework From Boltzmann Transport to Proton Treatment Planning
Studies in Applied Mathematics, Volume 157, Issue 2, August 2026.ABSTRACT We develop a unified stochastic–deterministic framework for proton transport in radiotherapy. The deterministic formulation is based on a Boltzmann–Fokker–Planck (BFP) equation with continuous slowing‐down, angular diffusion, and scattering terms, posed in a kinetic variational setting.
Andreas E. Kyprianou +2 more
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