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We survey results devoted to the lattice of varieties of monoids. Along with known results, some unpublished results are given with proofs. A number of open questions and problems are also formulated.

Group Theory · Mathematics 2022-10-24 Sergey V. Gusev , Edmond W. H. Lee , Boris M. Vernikov

Globular clusters have long been known to contain large excesses of a variety of objects formed through dynamical processes. The past few years have seen a dramatic increase in our knowledge about these systems.

Astrophysics · Physics 2009-11-13 Thomas J. Maccarone , Christian Knigge

Some inequalities for different types of convexity are established.

Classical Analysis and ODEs · Mathematics 2013-09-27 Merve Avci Ardic

Throughout this book, we discuss some open problems in various branches of science, including mathematics, theoretical physics, astro-physics, geophysics etc. It is of our hope that some of the problems discussed in this book will find…

General Mathematics · Mathematics 2007-05-23 Florentin Smarandache , V. Christianto , Fu Yuhua , R. Khrapko , J. Hutchison

Complexity is an interdisciplinary concept which, first of all, addresses the question of how order emerges out of randomness. For many reasons matrices provide a very practical and powerful tool in approaching and quantifying the related…

Soft Condensed Matter · Physics 2008-12-18 S. Drozdz , J. Kwapien , J. Speth , M. Wojcik

In this article we present a detailed study of the existing constructions of colilimits in the category of symmetrical operations. In addition, some examples of operads obtained from colimits of other operads are presented.

Category Theory · Mathematics 2022-11-29 Jesús Sánchez-Guevara

We give a broad survey of recent results in Enumerative Combinatorics and their complexity aspects.

Combinatorics · Mathematics 2018-04-03 Igor Pak

This paper presents an overview of the current state of knowledge in the field of equivariant map algebras and discusses some open problems in this area.

Representation Theory · Mathematics 2013-12-31 Erhard Neher , Alistair Savage

Compared with constraint satisfaction problems, counting problems have received less attention. In this paper, we survey research works on the problems of counting the number of solutions to constraints. The constraints may take various…

Artificial Intelligence · Computer Science 2020-12-29 Jian Zhang , Cunjing Ge , Feifei Ma

A graph is $\ell$-choosable if, for any choice of lists of $\ell$ colors for each vertex, there is a list coloring, which is a coloring where each vertex receives a color from its list. We study complexity issues of choosability of graphs…

Discrete Mathematics · Computer Science 2017-08-14 Marc Demange , Dominique de Werra

We discuss some aspects of Extrapolation theory. The presentation includes many examples and open problems.

Functional Analysis · Mathematics 2020-04-09 Sergey Astashkin , Mario Milman

The problem is posed to find out for arbitrary nonvoid sets $X$ which are all the mappings $T : X \longrightarrow X$ that can be defined and each separately identified through means of categories alone. As argued, this problem may have a…

General Mathematics · Mathematics 2007-09-05 Elemer E. Rosinger

Software ecosystems are collections of projects that are developed and evolve together in the same environment. Existing literature investigates software ecosystems as isolated entities whose boundaries do not overlap and assumes they are…

Software Engineering · Computer Science 2018-12-14 Eleni Constantinou , Alexandre Decan , Tom Mens

A number of unsolved problems and open questions about the nature and the properties of supernovae are identified and briefly discussed. Some suggestions and directions toward possible solutions are also considered.

Solar and Stellar Astrophysics · Physics 2015-05-13 Nino Panagia

In many everyday categories (sets, spaces, modules, ...) objects can be both added and multiplied. The arithmetic of such objects is a challenge because there is usually no subtraction. We prove a family of cases of the following principle:…

Category Theory · Mathematics 2010-02-04 Marcelo Fiore , Tom Leinster

The goal of this paper is to consider some relations between varieties of representations of groups and varieties of associative algebras. The main emphasis is put on the varieties of representations of groups induced by the varieties of…

Representation Theory · Mathematics 2009-07-21 Elena Aladova , Boris Plotkin

Work on different classification problems is described as: the classification of integrable vector evolution equations, NLS systems with two vector unknowns, systems with one scalar and one vector unknown, classification of integrable…

Exactly Solvable and Integrable Systems · Physics 2007-05-23 Thomas Wolf

You will find here a number of (mostly) elementary physics problems dealing mainly with uniform motion kinematics. In preparing this collection I have tried to create original situations that could help bring motivation to an introductory…

Physics Education · Physics 2007-05-23 Oscar Bolina

The Locker Problem is frequently used in introducing some topics in elementary number theory like divisors and multiples. It appears in many curricula ranging from elementary, secondary and up to tertiary level. In this paper, I will…

Number Theory · Mathematics 2013-07-25 Keneth Adrian P. Dagal

This work investigates topological chaos for homeomorphisms of the open annulus, introducing a new set of sufficient conditions based on points with distinct rotation numbers and their topological relation to invariant continua. These…

Dynamical Systems · Mathematics 2025-06-26 Alejandro Passeggi , Fabio Armando Tal