Preface
to 
Mathematical papers in honour of Eduardo Marques de Sá
O. Azenhas, A. L. Duarte, J. F. Queiró, A. P. Santana, editors
Departamento de Matemática - Universidade de Coimbra, 2006.




This collection of mathematical papers is dedicated to our colleague and friend Eduardo Marques de Sá on the occasion of his 60th birthday.

 

Throughout his professional life, Marques de Sá has fulfilled many roles, as a researcher of high calibre, as an outstanding teacher, as mentor of students at all levels (including six PhD students) and in many different areas, as a successful popularizer of Mathematics, as an active participant in Department life. Common traits can be detected in his activities: exacting standards, an absolute intellectual integrity, and an intense passion for Mathematics, all of Mathematics. If a subject attracts his attention, he will not leave it until understanding is complete. A problem will be abandoned only after the most thorough effort to solve it.

 

He has always taken his teaching very seriously. This can be gauged by a simple fact: there are few courses taught by Marques de Sá in the last 30 years for which he has not carefully prepared a set of notes for the students. For many years these were simply handwritten, but were even clearer than if they were typed. As he moved from course to course, many subjects were covered, from Analysis in several variables and Complex Analysis to Commutative Algebra and advanced Logic, with the texts running sometimes in the hundreds of pages. With characteristic modesty, he never thought of transforming these notes into formal books, although they were always highly polished and original. Some of them he may even have forgotten by now.

 

A similar detachment can be seen in his research. Of course he has published a number of papers, currently around 50 (one of them, written with three co-authors during a long visit to the USA, is possibly the most cited among papers by Portuguese mathematicians; another was the backbone of his PhD thesis, for which he was awarded the Householder Prize). But the actual studying and thinking about Mathematics, as well as helping others with their work, was and is always the most important thing to him. More than once he had to be pushed by colleagues to write up and submit his results to a journal.

 

One set of writings he is justifiably proud of is the comparative study of Mathematics curricula and textbooks for basic and secondary levels in Portugal and several other European countries. This was carried out in the late 1990s by a group chaired by Marques de Sá, following a consultation from the government to the Portuguese Mathematical Society.

 

Marques de Sá’s published writings do not give the full picture of his personality and achievements. To read his notes and papers is always an enriching experience, but to meet him personally is to come in contact with an exceptional mind.

 

We would like to thank the mathematicians who contributed with their work to this volume. We also thank our colleague Júlio Neves for his help with the editing process. The financial support of the Coimbra Mathematics Center and Department is gratefully acknowledged.

 

Coimbra, November 2006

The editors