ISSN 1201-561X
T A C
6
THEORY AND APPLICATIONS OF CATEGORIES
Volume 7, 2000
On branched covers in topos theory
Jonathon Funk 1
A pseudo representation theorem for various categories of relations
M. Winter 23
Pure morphisms of commutative rings are effective descent morphisms for modules – a new proof
Bachuki Mesablishvili 38
On saturated classes of morphisms
Carles Casacuberta and Armin Frei 43
Factorization systems for symmetric cat-groups
Stefano Kasangian and Enrico Vitale 47
Balanced coalgebroids
Paddy McCrudden 71
On the monadicity of categories with chosen colimits
G. M. Kelly and Stephen Lack 148
c The Editors of Theory and Applications of Categories 2000. Permission to copy for private use granted.
Theory and Applications of Categories,Vol. 7 ii
M-Completeness is seldom monadic over graphs
J. Ad´ amek and G.M. Kelly 171
Normal functors and strong protomodularity
Dominique Bourn 206
Central extensions in Malt’sev varieties
G. Janelidze and G.M. Kelly 219
On the object-wise tensor product of functors to modules
Marek Golasi´ nski 227
Quasi-varieties of presheaves
Enrico M. Vitale 236
Solution manifolds for systems of differential equations
John F. Kennison 239
A simplicial description of the homotopy category of simplicial groupoids
A. R. Garzon, J. G. Miranda and R. Osorio 263
Geometric and Higher Order Logic in terms of Abstract Stone Duality
Paul Taylor 284
Theory and Applications of Categories,Vol. 7 iii THEORY AND APPLICATIONS OF CATEGORIES (ISSN 1201-561X) will disseminate articles that significantly advance the study of categorical algebra or methods, or that make significant new contribu- tions to mathematical science using categorical methods. The scope of the journal includes: all areas of pure category theory, including higher dimensional categories; applications of category theory to algebra, geometry and topology and other areas of mathematics; applications of category theory to computer science, physics and other mathematical sciences; contributions to scientific knowledge that make use of categorical methods.
Articles appearing in the journal have been carefully and critically refereed under the responsibility of members of the Editorial Board. Only papers judged to be both significant and excellent are accepted for publication.
The method of distribution of the journal is via the Internet toolsWWW/ftp. The journal is archived electronically and in printed paper format.
Subscription information.
Individual subscribers receive (by e-mail) abstracts of articles as they are published. Full text of published articles is available in .dvi, Postscript and PDF. Details will be e-mailed to new subscribers. To subscribe, send e-mail to [email protected] including a full name and postal address. For institutional subscription, send enquiries to the Managing Editor, Robert Rosebrugh, [email protected].Information for authors.
The typesetting language of the journal is TEX, and LATEX is the preferred flavour. TEX source of articles for publication should be submitted by e-mail directly to an appropriate Editor. They are listed below. Please obtain detailed information on submission format and style files from the journal’s WWW server athttp://www.tac.mta.ca/tac/. You may also write [email protected] to receive details by e-mail.Editorial board.
John Baez, University of California, Riverside: [email protected] Michael Barr, McGill University: [email protected]
Lawrence Breen, Universit´e Paris 13: [email protected] Ronald Brown, University of North Wales: [email protected] Jean-Luc Brylinski, Pennsylvania State University: [email protected] Aurelio Carboni, Universit`a dell Insubria: [email protected] P. T. Johnstone, University of Cambridge: [email protected] G. Max Kelly, University of Sydney: [email protected] Anders Kock, University of Aarhus: [email protected]
F. William Lawvere, State University of New York at Buffalo: [email protected] Jean-Louis Loday, Universit´e de Strasbourg: [email protected]
Ieke Moerdijk, University of Utrecht: [email protected] Susan Niefield, Union College: [email protected]
Robert Par´e, Dalhousie University: [email protected]
Andrew Pitts, University of Cambridge: [email protected] Robert Rosebrugh, Mount Allison University: [email protected] Jiri Rosicky, Masaryk University: [email protected]
James Stasheff, University of North Carolina: [email protected] Ross Street, Macquarie University: [email protected] Walter Tholen, York University: [email protected] Myles Tierney, Rutgers University: [email protected] Robert F. C. Walters, University of Insubria: [email protected] R. J. Wood, Dalhousie University: [email protected]
