Coimbra Mathematical Texts – serie

This book provides an introduction to some key subjects in algebra and topology. It consists of comprehensive texts of some hours courses on the preliminaries for several advanced theories in (categorical) algebra and topology. Often, this kind of presentations is not so easy to find in the literature, where one begins articles by assuming a lot of knowledge in the field. This volume can both help young researchers to quickly get into the subject by offering a kind of « roadmap » and also help master students to be aware of the basics of other research directions in these fields before deciding to specialize in one of them. Furthermore, it can be used by established researchers who need a particular result for their own research and do not want to go through several research papers in order to understand a single proof. Although the chapters can be read as « self-contained » chapters, the authors have tried to coordinate the texts in order to make them complementary.The seven chapters of this volume correspond to the seven courses taught in two Summer Schools that took place in Louvain-la-Neuve in the frame of the project Fonds d’Appui à l’Internationalisation of the Université catholique de Louvain to strengthen the collaborations with the universities of Coimbra, Padova and Poitiers, within the Coimbra Group.

This book provides an introduction to some key subjects in algebra and topology. It consists of comprehensive texts of some hours courses on the preliminaries for several advanced theories in (categorical) algebra and topology. Often, this kind of presentations is not so easy to find in the literature, where one begins articles by assuming a lot of knowledge in the field. This volume can both help young researchers to quickly get into the subject by offering a kind of « roadmap » and also help master students to be aware of the basics of other research directions in these fields before deciding to specialize in one of them. Furthermore, it can be used by established researchers who need a particular result for their own research and do not want to go through several research papers in order to understand a single proof. Although the chapters can be read as « self-contained » chapters, the authors have tried to coordinate the texts in order to make them complementary.The seven chapters of this volume correspond to the seven courses taught in two Summer Schools that took place in Louvain-la-Neuve in the frame of the project Fonds d’Appui à l’Internationalisation of the Université catholique de Louvain to strengthen the collaborations with the universities of Coimbra, Padova and Poitiers, within the Coimbra Group.

Given a finite-dimensional Galois extension of fields, the classical bijection between the intermediate field extensions and the subgroups of the corresponding Galois group was extended by Grothendieck as an equivalence between finite-dimensional split algebras and finite sets on which the Galois group acts.

This textbook arises from a master’s course taught by the author at the University of Coimbra. It takes the reader from the very classical Galois theorem for fields to its generalization to the case of rings. Given a finite-dimensional Galois extension of fields, the classical bijection between the intermediate field extensions and the subgroups of the corresponding Galois group was extended by Grothendieck as an equivalence between finite-dimensional split algebras and finite sets on which the Galois group acts. Adding further profinite topologies on the Galois group and the sets on which it acts, these two theorems become valid in arbitrary dimension. Taking advantage of the power of category theory, the second part of the book generalizes this most general Galois theorem for fields to the case of commutative rings. This book should be of interest to field theorists and ring theorists wanting to discover new techniques which make it possible to liberate Galois theory from its traditional restricted context of field theory. It should also be of great interest to category theorists who want to apply their everyday techniques to produce deep results in other domains of mathematics.

The aim of this book is to honor the memory of Professor José Carlos Petronilho and hence focuses on his main research areas (Special Functions, Orthogonal Polynomials, Approximation Theory).

The aim of this book is to honor the memory of Professor José Carlos Petronilho and hence focuses on his main research areas (Special Functions, Orthogonal Polynomials, Approximation Theory). It is a collaborative book and among the contributing authors are outstanding leaders in the field. The book addresses different topics exploring the connection between the areas already mentioned and their applications, from different perspectives and using several tools, both analytical and algebraic. Beside the researches working in these topics, the book potentially interests the readers working in areas of Mathematics, Science and Technology where Approximation Theory, Special Functions and Orthogonality are potentially useful tools.

This book collects the groundbreaking research presented at the plenary lectures of the First Brazil-Portugal Joint Meeting in Mathematics, held in Salvador, Brazil, from August 14 to 20, 2022. This historic event marked the bicentennial of Brazil's independence and celebrated the strengthening of scientific cooperation between the two nations. With contributions from international experts, these proceedings provide a comprehensive overview of the latest advances in various areas of mathematics. It contains a stimulating mix of research articles and exclusive surveys of the state of the art in current topics. It collects 7 articles on various topics, including transmission problems and PDEs, linear and nonlinear fractional PDEs of interacting particle systems, complexity in continuous optimization, Poisson manifolds, real and complex singularities, Reeb flows, and statistical extreme value theory. It serves as a testament to the growing partnership between the Brazilian and Portuguese mathematical communities.This volume will serve as a source of inspiration for a broad range of researchers and research students, especially professional mathematicians with ties to Brazil and/or Portugal.