Title: Creation and 40 years evolution of a Journal

Author: Andrée C. Ehresmann

Characters: Cahiers de Topologie et Géométrie Différentielle Catégoriques

Dates: 1957-2000

Creation and 40 years evolution of a journal:

Cahiers de Topologie et Géométrie Différentielle Catégoriques

by Andrée C. Ehresmann

In the early fifties, Charles Ehresmann had organized a Topology Seminar in Strasbourg, the proceedings of which were published in 3 volumes, under the title:

"Colloque de Topologie de Strasbourg".

When he came to the "Université de Paris" (not yet divided in 13 universities!) in the late fifties, he organized a weekly Seminar on Topology and Differential Geometry at the "Institut Poincaré". At this time, the proceedings of the several Paris Seminars were printed in the series: "Séminaires de l'Institut Poincaré". Hence Charles' 1957-58 Seminar was published under the title:

"Séminaire de Topologie et Géométrie Différentielle", Vol. I.

The rule of the series was to print exactly the texts of the lectures which had been given. But Charles did not like strict rules, and he had some clashes with the very dedicated and meticulous Editor, Paul Belgodère, because he wanted to include a larger choice of papers; in particular he insisted to print the complete text of my "3^rd cycle" thesis (on infinite-dimensional polyhedrons), in this volume, and not only the part I had exposed in his seminar.

Thus, to have more freedom, we thought of creating an independent publication, not only devoted to the proceedings of the Seminar. The fortuitous meeting of an unused 'Varityper' machine allowed the realization of this project. Until 1966, volumes appeared without strict periodicity (about one volume per annum) and the initial title changed little by little to become in 1966:

"Cahiers de Topologie et Géométrie Diférentielle".

In 1967 the "Cahiers" were converted into a formal quarterly journal (with no more links with the Seminar), and their current presentation was adopted. From 1967 to 1972, they were published by the Editions Dunod. But a merger of Dunod in 1972 raised problems, and we decided to publish them ourselves, in Paris until 1975, then in Amiens.

In Paris, most of the composition of the texts was carried out by secretaries made available for this journal by the "Centre National de la Recherche Scientifique". But when we moved to Amiens at the end of 1975, we had to give up this material aid, whose maintenance was subordinated to conditions unacceptable for us.

Up to his death in 1979, Charles was the Director of the "Cahiers", and I acted as the Editor. After that, I wanted to pursue this publication which had hold such an important place in our life during twenty years. Thus, I became Director of the publication, but I felt the need to be helped in the selection of the papers, and I created an international Editorial Board.

From 1980 to 1983, supplements* were added, consisting of the 4 parts (in 7 volumes) of:

"Charles Ehresmann: Œuvres complètes et commentées",

(Editor: A.C. Ehresmann). They contain all the articles de C. Ehresmann, with long comments (in English) updating these papers.

Through the years, the contents of the "Cahiers" had slowly changed, because of our greater and greater involvement in Category Theory. For instance, they contain the proceedings of several international Category Meetings (those we organized in Amiens in 1973, 1975, 1980; the 1989 Bangor and 1990 Cambridge meetings). Thus the title was partly misleading. Without abandoning the name chosen by Charles, René Guitart suggested a slight modification, whence the present title:

"Cahiers de Topologie et Géométrie Différentielle Catégoriques".

When the electronic journal

"Theory and Application of Categories"

was created (oddly enough, with the same name as our Paris-Amiens research team "Théorie et Applications des Catégories" in the seventies!), I thought that some collaboration could be fruitful for both publications, since their coverage is very similar. It led to a regular exchange of table of contents: each year, the "Cahiers" print the table of contents of "T_AC" while their own table of contents is e-mailed to the "T_AC" subscribers.

What will be the future of "paper" journals in the Internet era? I don't know and I would like to thank all those who make possible the continuation of the "Cahiers", namely the authors who send interesting papers and the subscribers without whom the journal (which has no material help whatsoever) would die.