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Aims and scope
The NorthWestern European Journal of Mathematics publishes research articles and surveys in all areas of pure and applied mathematics including history of mathematics. Articles can be submitted in Dutch, English, French or German.
Editorial Committee
Editor in Chief: Olivier Goubet
Associate Editors:
Universität der Bundeswehr München, Germany Numerical analysis for partial differential equations Karine Beauchard (*)
ENS Rennes, France Joachim von Below (*)
Université du Littoral Côte d'Opale, France Partial differential equations, operator theory, graph theory Christophe Biernacki (*)
Université de Lille, France Statistical, modelbased data analysis Claire ChainaisHillairet (*)
Université de Lille, France Numerical analysis for partial differential equations Monique Dauge (*)
Rennes I, France Spectral theory, high order methods, singularities in partial differential equations Sinnou David (*)
Université Paris VI, France Arithmetic Youri Davydov (*)
Université de Lille, France Stochastic processes, limit theorems, stochastic geometry Pierre Dèbes (*)
Université de Lille, France Number theory, galois theory and arithmetic geometry Jérôme Droniou (*)
Monash University, Australia Elliptic and parabolic equations (theoretical and numerical study) Aziz El Kacimi (*)
Université de Valenciennes et du Hainaut Cambrésis, France Geometry, global analysis on manifolds Shalom Eliahou (*)
Université du Littoral Côte d'Opale, France Discrete mathematics Peter Fleischmann (*)
University of Kent, United Kingdom Algebra, group theory, representation theory, invariant theory Benoît Fresse (*)
Université de Lille, France Algebraic topology, operad theory Emmanuel Fricain (*)
Université de Lille, France Functional analysis, operator theory, complex analysis of one variable Eamonn Gaffney (*)
Oxford University, United Kingdom Applied mathematics in the life sciences and low Reynolds flows Antoine Gloria (*)
Université Sorbonne, France Homogenization of partial differential equations Gilles Godefroy (*)
Université Paris VI, France Functional analysis Karl GrosseErdmann (*)
Université de Mons, Belgium Functional analysis, operator theory, linear dynamics BaoZhu Guo (*)
Academy of Mathematics and Systems Science, Academia Sinica, Beijing, China System control, partial differential equation, semigroup of linear operators Pascal Lambrechts (*)
Université Catholique de Louvain, Belgium Algebraic topology
Université d'Artois, France Functional analysis André Leroy (*)
Université d'Artois, France Non commutative ring theory, module theory, error correcting codes JeanJacques Loeb (*)
Université d'Angers, France Complex analysis, in particular when related to group theory Florian Luca (*)
University of Witwatersrand, Johannesburg, SouthAfrica Analytic and diophantine number theory Kaisa Matomäki (*)
University of Turku, Finland Analytic and combinatorial number theory Christian Michaux (*)
Université de Mons, Belgium Mathematical logic Ieke Moerdijk (*)
University of Utrecht, Netherlands Algebraic topology, category theory Alejandro Murua (*)
Université de Montréal, Canada Statistical learning, clustering, pattern recognition Hiroaki Nakamura (*)
Osaka University, Japan Arithmetic geometry Jan van Neerven (*)
Delft University of Technology, Netherlands Functional analysis, stochastic analysis Johannes Nicaise (*)
Katholieke Universiteit Leuven, Belgium Algebraic and arithmetic geometry Serge Nicaise (*)
Université Polytechnique HautsdeFrance, France Partial differential equations, numerical analysis, control theory Rimas Norvaisa (*)
Vilnius University, Lituany Probability theory and stochastic processes, nonlinear functional analysis Giovanni Peccati (*)
University of Luxembourg, Luxembourg Random fields, stochastic analysis, stochastic geometry, noncommutative probability Teimuraz Pirashvili (*)
University of Leicester, United Kingdom Homological algebra and polynomial functors Olivier Ramaré (*)
Université d'AixMarseille, France Analytic number theory Sylvie Roelly (*)
University of Potsdam, Germany Stochastic differential equations, statistical mechanics, branching processes Isar Stubbe (*)
Université du Littoral Côte d'Opale, France Category theory, order theory Charles Suquet (*)
Université de Lille, France Rossana Tazzioli (*)
Université de Lille, France History of mathematics Jie Wu (*)
Institut Élie Cartan, Nancy, France Analytic number theory and modular forms
Fields Editor: Deirdre Haskell Managing Editor: Philippe Heinrich
Policies
Peer Review Process
The reviewing process is simple anonymous, that is the reviewers are kept anonymous while the authors are not. The authors are asked to provide the names of one or two potential associate editors who will manage their article. Then, the editor in chief assigns the article to an associate editor who seeks reviewer(s). Once the reviews are available, the associate editor reports his decision to the whole editorial board which takes the final decision regarding the acceptance of the article.
Open Access Policy
The NorthWestern European Journal of Mathematics adheres to the principles of Fair Open Access, and is a member of the Free Journal Network. No charges are levied on authors. Articles are freely available to anyone as soon they are accepted. Hard copies of a volume are available at the cost of the paper and delivery.
Copyright Notice
Authors keep their copyrights. Thus they can reuse figures, article parts or any material they need for subsequent work. The contract license is the Creative Commons License CCBY which is the most flexible contract maximising the readership on publication.
Author Guidelines
Articles submission:
 At the initial stage, the authors have only to send by mail a PDF file to the managing editor (philippe.heinrichNOSPAMATunivlille.fr).
 Only when the article is accepted or subject to minor revisions are they asked to ensure it complies with the journal format. Here you can find an example of a LaTeX and a biblatex file. The template and the documentation in French and also in English.
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Current Volume:
The current volume is the volume of 2023.

Dans la perspective de construire une théorie de Galois infinie pour les extensions non extérieures, nous montrons dans ce texte que le monoïde des endomorphismes d'une $Z$extension intérieure filtrée s'identifie à la complétion procentrale du groupe de ses automorphismes intérieurs. En particulier, ce monoïde a une structure topologique naturelle qui fait de lui un espace complet et totalement discontinu.
In order to build an infinite Galois theory for nonouter extensions, we show that the monoïd of endomorphisms of a filtered inner $Z$extension identifies with the procentral completion of the group of its inner automorphisms. In particular, this monoid has a natural topological structure for which it is a complete and totally discontinuous space. 
Let $H$ be a Hilbert space and $(\Omega,\mathcal{F},\mu)$ a probability space. A Hilbert point in $L^p(\Omega; H)$ is a nontrivial function $\varphi$ such that $\\varphi\_p \leq \\varphi+f\_p$ whenever $\langle f, \varphi \rangle = 0$. We demonstrate that $\varphi$ is a Hilbert point in $L^p(\Omega; H)$ for some $p\neq2$ if and only if $\\varphi(\omega)\_H$ assumes only the two values $0$ and $C>0$. We also obtain a geometric description of when a sum of independent Rademacher variables is a Hilbert point.

In this paper we consider sequences of nonlinear functionals of Gaussian random fields. We prove their convergence to multifractional processes which generalize Hermite processes.

In this work, we numerically investigate how a defect can affect the behavior of traveling explosive solutions of quintic NLS equation in the onedimensional case. Our numerical method is based on a CrankNicolson scheme in the time, finite difference method in space including a Perfectly Matched Layer (PML) treatment for the boundary conditions. It is observed that the defect splits the incident wave in one reflected part and one transmitted part; hence the dynamics of the solution may be changed and the blowup may be prevented depending on the values of the defect amplitude $Z$. Moreover, it is numerically found that the defect can be considered as a barrier for large $Z$.

Given an unbalanced open quantum graph, we derive a formula relating sums over its scattering resonances with integrals on horizontal lines in the complex plane. We deduce lower bounds on the number of resonances (in bounded regions of the complex plane) that are independent of the size of the graph. We also deduce partial results indicating that BenjaminiSchramm convergence of open quantum graphs should imply convergence of the empirical spectral measures.

Following an idea of J. Shapiro, we give a simple proof of the fact that an element of the Gordon Hedenmalm class $\Phi$ such that $\Phi(\infty)=\infty$ defines a contractive composition operator $C_\Phi$ on the space $\mathcal{H}^2$ of Dirichlet series.
Acknowledgements
This journal owes much to the following persons: Denis Bitouzé for LaTex support, Nadine Demarelle for printing service, Mohammed Khabzaoui for computer engineering issues and Omar Aouadi for secretarial tasks.
Supports
The Paul Painlevé Laboratory and the Department of Mathematics of Lille provide financial support which ensures that this journal stays open access. The French Mathematical Society (SMF), the Dutch Mathematical Society (KWG), the Luxembourg Mathematical Society (SML) and the Fields Institute support this project, of a mathematics journal by a nonprofit publisher, making research available free of charge for readers and authors.