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This note offers an unusual approach of studying a class of modules inasmuch as it is investigating a subclass of the category of modules over a valuation domain. This class is far from being a full subcategory, it is not even a category.…

Commutative Algebra · Mathematics 2023-02-01 Peter Danchev , Laszlo Fuchs

By Easton's theorem one can force the exponential function on regular cardinals to take rather arbitrary cardinal values provided monotonicity and Koenig's lemma are respected. In models without choice we employ a "surjective" version of…

Logic · Mathematics 2013-08-09 Anne Fernengel , Peter Koepke

It is known that the value of a call option in the case of constant elasticity processes (CEV) with the indicator $\alpha$ exceeding the critical $\alpha=1$ is determined in a non-unique way. We show how, based on an already existing…

Analysis of PDEs · Mathematics 2025-02-03 Ekaterina A. Ladykova , Olga S. Rozanova

Let $K$ be a number field defined by a monic irreducible polynomial $F(X) \in \mathbb{Z}[X]$, $p$ a fixed rational prime, and $\nu_p$ the discrete valuation associated to $p$. Assume that $\overline{F}(X)$ factors modulo $p$ into the…

Number Theory · Mathematics 2018-02-20 Abdulaziz Deajim , Lhoussain El Fadil

The Fourier series of continuous functions of constant absolute value have interesting properties : according to the main theorems of the article, if the coefficients with positive indexes are square-summable with respect to a certain…

Classical Analysis and ODEs · Mathematics 2010-03-31 Jean Bourgain , Jean-Pierre Kahane

A famous theorem of Bers and Finn states that isolated singularities of solutions to the non-parametric minimal surface equation are removable. We show that this result remains valid, if the area functional is replaced by a general…

Analysis of PDEs · Mathematics 2022-06-02 Michael Bildhauer , Martin Fuchs

We prove the existence of nontrivial unbounded exceptional domains in the Euclidean space $\R^N$, $N\geq4$. These domains arise as perturbations of complements of straight cylinders in $\R^N$, and by definition they support a positive…

Analysis of PDEs · Mathematics 2023-06-21 Ignace Aristide Minlend , Tobias Weth , Jing Wu

Gapless criteria that can efficiently determine whether a crystal is gapless or not are particularly useful for identifying topological semimetals. In this work, we propose a sufficient gapless criterion for three-dimensional…

Mesoscale and Nanoscale Physics · Physics 2020-07-21 Jiabin Yu , Zhi-Da Song , Chao-Xing Liu

Suppose that R\rightarrow S is an extension of local domains and \nu^* is a valuation dominating S. We consider the natural extension of associated graded rings along the valuation gr_{\nu^*}(R)\rightarrow gr_{\nu^*}(S). We give examples…

Algebraic Geometry · Mathematics 2016-12-05 Steven Dale Cutkosky

The long-standing Auslander and Reiten Conjecture states that a finitely generated module over a finite-dimensional algebra is projective if certain Ext-groups vanish. Several authors, including Avramov, Buchweitz, Iyengar, Jorgensen,…

Commutative Algebra · Mathematics 2019-01-15 Olgur Celikbas , Henrik Holm

We show that the Axiom of Dependent Choices, $\operatorname{DC}$, holds in countably iterable, passive premice $\mathcal{M}$ construced over their reals which satisfy the Axiom of Determinacy, $\operatorname{AD}$, in a…

Logic · Mathematics 2019-07-08 Sandra Müller

It has been a well-known fact since Euclid's time that there exist infinitely many rational primes. Two natural questions arise: In which other rings, sufficiently similar to the integers, are there infinitely many irreducible elements? Is…

Commutative Algebra · Mathematics 2007-05-23 Fabrizio Zanello

This paper investigates the link between the Maximum Principle and the sign of the (generalized) principal eigenvalue for elliptic operators in unbounded domains. Our approach covers the cases of Dirichlet, Neumann, and (indefinite) Robin…

Analysis of PDEs · Mathematics 2021-02-16 Samuel Nordmann

We study the question of $\mathcal{L}_{\mathrm{ring}}$-definability of non-trivial henselian valuation rings. Building on previous work of Jahnke and Koenigsmann, we provide a characterization of henselian fields that admit a non-trivial…

Logic · Mathematics 2025-11-12 Margarete Ketelsen , Simone Ramello , Piotr Szewczyk

We present a unifying framework of residual domination for (expansions of) henselian valued fields of equicharacteristic zero, encompassing some valued fields with operators. We show that the class of residually dominated types coincides…

We complete our proof that given an overconvergent F-isocrystal on a variety over a field of positive characteristic, one can pull back along a suitable generically finite cover to obtain an isocrystal which extends, with logarithmic…

Number Theory · Mathematics 2014-01-14 Kiran S. Kedlaya

The derived functors $\lim^n$ of the inverse limit are widely studied for their topological applications, among which are some repercussions on the additivity of strong homology. Set theory has proven useful in dealing with these functors,…

Logic · Mathematics 2024-04-16 Matteo Casarosa

Persistence modules serve as the algebraic foundation for topological data analysis, typically studied as representations of posets over a field. This article extends the structural and decomposition theory of persistence modules to the…

Algebraic Topology · Mathematics 2026-02-17 Nadiya Upegui Keagy

For a finite group $G$ acting faithfully on a finite dimensional $F$-vector space $V$, we show that in the modular case, the top degree of the vector coinvariants grows unboundedly: $\lim_{m\to\infty} \topdeg F[V^{m}]_{G}=\infty$. In…

Commutative Algebra · Mathematics 2015-12-29 Martin Kohls , Müfit Sezer

The derived functors $\lim^n$ of the inverse limit find many applications in algebra and topology. In particular, the vanishing of certain derived limits $\lim^n \mathbf{A}[H]$, parametrized by an abelian group $H$, has implications for…

Logic · Mathematics 2024-11-26 Matteo Casarosa , Chris Lambie-Hanson