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🔍 william casper 📂 Mathematics
Showing 2602 results for "william casper" in Mathematics
Mathematics Preprint PDF DOI

The $H$-linkage problems in sparse robustly expanding digraphs

Zhilan Wang, Jin Yan · 2026

The Nash-Williams conjecture establishes degree sequence conditions ensuring Hamilton cycles in digraphs. An asymptotic version of this conjecture for large digraphs was independently derived by sever…

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Mathematics Preprint PDF DOI

Directional curvature and medial axis

Adam Bia{l}ozyt, Dominik Bysiewicz, Maciej P. Denkowski · 2026

The medial axis $M_X$ of a closed set $X\subset \mathbb{R}^n$ is the set of points from the ambient space that admit more than one closest point in $X$. We study the problem of reaching the singularit…

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Mathematics Preprint PDF DOI

The local Calder\'on problem and the determination at the boundary of a complex anisotropic admittivity

Jessica Crosse, Romina Gaburro · 2026

We address Calder\'on's problem of stably determining the anisotropic complex admittivity $\sigma$ in a domain $\Omega\subset\mathbb{R}^n$, with $n\geq3$, representing a conducting medium, in terms of…

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Mathematics Preprint PDF DOI

Semistable reductions and minimalities of invariants for group scheme actions on projective schemes

Rin Gotou, Yusuke Okuyama · 2026

Let $K$ be an algebraically closed and complete non-archimedean and non-trivially valued field, and let $G$ be a reductive group scheme acting on a flat projective scheme $X$ defined over the base rin…

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Mathematics Preprint PDF DOI

Triangle packings in randomly perturbed graphs

Xinbu Cheng, Hong Liu, Lanchao Wang, Zhifei Yan · 2026

The longstanding Nash-Williams conjecture asserts that every $K_3$-divisible graph $G$ with $\delta(G)\ge 3n/4$ admits a triangle decomposition. In the random setting, Frankl and R\"odl showed that, w…

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Mathematics Preprint PDF DOI

Bourgain's method for K-closedness in the semicommmutative setting

Hugues Moyart · 2026

In the early 1990s, J.Bourgain proved a general result $K$-closedness result in the context of classical harmonic analysis. In this paper, we extend Bourgain's method to the semicommutative setting, m…

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Mathematics Preprint PDF DOI

Calder\'on-Zygmund estimates for parabolic $p$-Laplacian systems with non-divergence form right-hand sides

Pedra Andrade, Verena Bogelein, Frank Duzaar, Kristian Moring · 2026

We establish local Calder\'on-Zygmund type estimates for weak solutions to nonlinear parabolic systems with $p$-growth and VMO coefficients. In particular, we prove that if the right-hand side belongs…

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Mathematics Preprint PDF DOI

Counterexamples to the Lorentzian Calder\'on problem

Lauri Oksanen, Miika Sarkkinen · 2026

We show that two non-isometric, smooth, globally hyperbolic Lorentzian metrics can have the same hyperbolic Dirichlet-to-Neumann map on an infinite cylinder with timelike boundary.…

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Mathematics Preprint PDF DOI

Function spaces and potential theory in the Orlicz setting

Pablo Ochoa, Ariel Salort · 2026

In this article, we study certain transcendental function spaces arising in potential theory within the framework of Orlicz spaces. Specifically, we generalize Bessel and Lizorkin-Triebel spaces to th…

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Mathematics Preprint PDF DOI

Weak solutions and weak-strong uniqueness for a Cahn-Hilliard type model with chemotaxis

Robert Lasarzik, Elisabetta Rocca, Giulio Schimperna · 2026

We prove existence of weak solutions and weak-strong uniqueness for a mathematical model which couples the evolution of a phase-parameter $\varphi$ satisfying a Cahn-Hilliard type relation with the on…

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Mathematics Preprint PDF DOI

On the transfer of stability from the local to the fractional anisotropic Calder\'on problem with exterior measurements

Hendrik Baers, Angkana Ruland · 2026

We study the quantitative transfer of uniqueness from the classical to the fractional Calder\'on problem with exterior data. This allows us to deduce the first stability estimates for the principal pa…

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Mathematics Preprint PDF DOI

Global mild solutions for a transport-diffusion equation with a rough drift

Diego Chamorro (LaMME), Anca-Nicoleta Marcoci, Liviu-Gabriel Marcoci · 2026

We construct here global mild solutions in a critical setting for a class of transport-diffusion equations with a drift term that involves rough Calder{\'o}n-Zygmund operators.…

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Mathematics Preprint PDF DOI

New Robust Streaming DMD with Forecasting

Zlatko Drmac, Ela {DJ}imoti · 2026

The Dynamic Mode Decomposition (DMD) and the more general Extended DMD (EDMD) are powerful tools for computational analysis of dynamical systems in data-driven scenarios. They are built on the theoret…

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Mathematics Preprint PDF DOI

Some results on the Dunkl-Williams constant

Javier Alonso, Pedro Martin · 2026

This paper presents a compilation of various formulas for calculating the Dunkl-Williams constant $DW(X)$ of a real normed linear space. The constant $DW_B(X)$ related to Birkhoff orthogonality is als…

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Mathematics Preprint PDF DOI

Real-Variable Theory of Hardy--Lorentz Spaces on Quasi-Ultrametric Spaces of Homogeneous Type with Reverse-Doubling Property

Chenfeng Zhu, Ryan Alvarado, Xianjie Yan, Dachun Yang, Wen Yuan · 2026

Let $(X,\mathbf{q},\mu)$ be an ultra-RD-space with upper dimension $n\in(0,\infty)$; i.e., it is a quasi-ultrametric space of homogeneous type whose measure $\mu$ satisfies an additional reverse doubl…

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Mathematics Preprint PDF DOI

Classification of Auslander-Gorenstein monomial algebras: The acyclic case

Viktoria Klasz, Markus Kleinau, Rene Marczinzik · 2026

We give a linear algebraic classification of Auslander regular acyclic monomial algebras via the Bruhat factorisation of the Coxeter matrix. Namely, we show under mild assumptions that a monomial acyc…

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Mathematics Preprint PDF DOI

Energy estimates for level sets of holomorphic functions and counterexamples to Calder\'on-Zygmund theory

Yifei Pan, Guokuan Shao, Jianfei Wang, Jujie Wu · 2026

We demonstrate that the failure of $L^1$ regularity in Calder\'on-Zygmund theory is a universal phenomenon: every non-constant holomorphic function in $\C^n$ generates a counterexample to the Poisson …

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Mathematics Preprint PDF DOI

Translation complete subgroups of affine Weyl-Heisenberg groups and their generalized wavelet systems

Hartmut Fuhr, Narjes Rashidi · 2026

The $n$-dimensional affine Weyl-Heisenberg group is a Lie group typically parameterized as $G_{aWH} = \mathbb{T} \times \mathbb{R}^n \times \widehat{\mathbb{R}^n} \times \mathrm{GL}(n, \mathbb{R})$, g…

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Mathematics Preprint PDF DOI

Segmentation of monotone data by Kobayashi-Warren-Carter type total variation energies

Yoshikazu Giga, Ayato Kubo, Hirotoshi Kuroda, Koya Sakakibara · 2026

We consider a Kobayashi-Warren-Carter (KWC) type total variation energy with a fidelity term. Since the energy is non-convex, the profiles of minimizers are quite different from those of the original …

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Mathematics Preprint PDF DOI

A Galerkin Finite Element Method for the Fractional Calder\'on Problem

Mukul Dwivedi, Jesse Railo, Andreas Rupp · 2026

We study a numerical reconstruction strategy for the potential in the fractional Calder\'on problem from a single partial exterior measurement. The forward model is the fractional Schr\"odinger equati…

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