From rrosebru@mta.ca Tue Jun 1 08:40:09 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 01 Jun 2004 08:40:09 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BV7aG-0000eY-00 for categories-list@mta.ca; Tue, 01 Jun 2004 08:37:32 -0300 Mime-Version: 1.0 (Apple Message framework v613) To: categories@mta.ca Message-Id: Content-Type: multipart/alternative; boundary=Apple-Mail-6-367120408 From: Rob Goldblatt Subject: categories: preprint on behavioural covarieties Date: Tue, 1 Jun 2004 12:08:22 +1200 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain;charset=ISO-8859-1;format=flowed Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 1 A preprint of a paper entitled "A comonadic account of behavioural covarieties of coalgebras" is available for downloading as a pdf file from www.mcs.vuw.ac.nz/~rob Rob Goldblatt ABSTRACT: A class K of coalgebras for an endofunctor T on the category of sets is=20= a behavioural covariety if it is closed under disjoint unions and=20 images of bisimulation relations (hence closed under images and domains=20= of coalgebraic morphisms, including subcoalgebras). K may be thought of=20= as the class of all coalgebras that satisfy some computationally=20 significant property. In any logical system suitable for specifying=20 properties of state-transition systems in the Hennessy-Milner style,=20 each formula will define a class of models that is a behavioural=20 variety. Assume that the forgetful functor on T-coalgebras has a right adjoint,=20= providing for the construction of cofree coalgebras, and let G^T be the=20= comonad arising from this adjunction. Then we show that behavioural=20 covarieties K are (isomorphic to) the Eilenberg-Moore categories of=20 coalgebras for certain comonads G^K naturally associated with G^T.=20 These are called pure subcomonads of G^T, and a categorical=20 characterization of them is given, involving a pullback condition on=20 the naturality squares of a transformation from G^K to G^T. We show that=A0 there is a bijective correspondence between = behavioural=20 covarieties of T-coalgebras and isomorphism classes of pure subcomonads=20= of G^T. =20= From rrosebru@mta.ca Tue Jun 1 08:41:05 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 01 Jun 2004 08:41:05 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BV7br-0000me-00 for categories-list@mta.ca; Tue, 01 Jun 2004 08:39:11 -0300 Message-ID: <40BC610D.7022F208@bangor.ac.uk> Date: Tue, 01 Jun 2004 11:57:17 +0100 From: Ronnie Brown X-Mailer: Mozilla 4.79 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: categories@mta.ca Subject: categories: Nonabelian algebraic topology Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-MailScanner-Information: Please contact the ISP for more information X-UWB-MailScanner: Found to be clean Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 2 This advertises Part I of a three part book with the above title. We are putting Part I (with overall TOC) on the web to awake interest and in the hope of getting comments and suggestions. Details are on http://www.bangor.ac.uk/~mas010/nonab-a-t.html Special interest for this list should be the use of higher categorical structures. Ronnie Brown and Rafael Sivera Villenueva Professor Emeritus R. Brown, Department of Mathematics, University of Wales, Bangor Dean St., Bangor, Gwynedd LL57 1UT, United Kingdom Tel. direct:+44 1248 382474|office: 382681 fax: +44 1248 361429 World Wide Web: home page: http://www.bangor.ac.uk/~mas010/ (Links to survey articles: Higher dimensional group theory Groupoids and crossed objects in algebraic topology) Centre for the Popularisation of Mathematics: http://www.cpm.informatics.bangor.ac.uk/ (reorganised site with new sculpture animations) From rrosebru@mta.ca Thu Jun 3 14:24:33 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Thu, 03 Jun 2004 14:24:33 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BVvuL-0005hg-00 for categories-list@mta.ca; Thu, 03 Jun 2004 14:21:37 -0300 Mime-Version: 1.0 (Apple Message framework v618) Content-Transfer-Encoding: 7bit Message-Id: <0CD2C118-B4DA-11D8-9714-000D9367EB64@vuw.ac.nz> Content-Type: text/plain; charset=US-ASCII; format=flowed To: categories@mta.ca From: Rob Goldblatt Subject: categories: preprint on behavioural covarieties available Date: Thu, 3 Jun 2004 09:16:01 +1200 X-Mailer: Apple Mail (2.618) Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 3 [Resent message] A preprint of a paper entitled "A comonadic account of behavioural covarieties of coalgebras" is available for downloading as a pdf file from www.mcs.vuw.ac.nz/~rob Rob Goldblatt ABSTRACT A class $K$ of coalgebras for an endofunctor $T:\Set\to\Set$ is a \textit{behavioural covariety} if it is closed under disjoint unions and images of bisimulation relations (hence closed under images and domains of coalgebraic morphisms, including subcoalgebras). $K$ may be thought of as the class of all coalgebras that satisfy some computationally significant property. In any logical system suitable for specifying properties of state-transition systems in the Hennessy-Milner style, each formula will define a class of models that is a behavioural variety. Assume that the forgetful functor on $T$-coalgebras has a right adjoint, providing for the construction of cofree coalgebras, and let $\G^T$ be the comonad arising from this adjunction. Then we show that behavioural covarieties $K$ are (isomorphic to) the Eilenberg-Moore categories of coalgebras for certain comonads $\G^K$ naturally associated with $\G^T$. These are called \textit{pure subcomonads} of $\G^T$, and a categorical characterization of them is given, involving a pullback condition on the naturality squares of a transformation from $\G^K$ to $\G^T$. We show that there is a bijective correspondence between behavioural covarieties of $T$-coalgebras and isomorphism classes of pure subcomonads of $\G^T$. From rrosebru@mta.ca Thu Jun 3 14:28:09 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Thu, 03 Jun 2004 14:28:09 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BVvzH-0006Gh-00 for categories-list@mta.ca; Thu, 03 Jun 2004 14:26:43 -0300 Content-class: urn:content-classes:message MIME-Version: 1.0 Subject: categories: UNILOG'05 - Montreux Date: Thu, 3 Jun 2004 14:15:40 +0200 Message-ID: From: "COSTA LEITE Alexandre" To: categories@mta.ca Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 4 =20 =20 ************************************************************************ ************************************************************************ ******************* 1st World Congress and School on Universal Logic (UNILOG 2005) http://www.uni-log.org =20 Montreux - Switzerland, School : March 26-30 ; Congress : March 31 - April 3, 2005=20 This event will focus on:=20 1) Techniques that can be used for a general theory of logics (Labelled deductive systems, Kripke structures, Logical matrices, etc.) ;=20 2) Studies of classes of logics (Substructural logics, Non monotonic logics, Paraconsistent logics, etc.)=20 3) Scope of validity and domain of application of fundamental theorems of logic (Completeness, Deduction, Cut-elimination, etc.) 4) Philosophical considerations about the nature of logic and the universality of some logical laws or axioms=20 The school is intended for advanced students and young researchers. There will be about 20 tutorials on many subjects: combination of logics, multiple conclusion logic, combinatory logic, logics and games, abstract model theory, logic as language vs. logic as calculus, category theory for logics, etc. Invited speakers of the congress will include A.Avron, D.Batens, J.Corcoran, M.Dunn, D.Gabbay, R.Jansana, A.Koslow, V.de Paiva, K.Segerberg. Contributed papers for the congress can be submitted before October 30, 2004.=20 More information on the website: http://www.uni-log.org =20 ************************************************************************ ******************************************************************** =20 =20 =20 =20 From rrosebru@mta.ca Sun Jun 6 09:34:43 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Sun, 06 Jun 2004 09:34:43 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BWwmr-0005Ae-00 for categories-list@mta.ca; Sun, 06 Jun 2004 09:30:05 -0300 From: Paul B Levy To: categories@mta.ca Subject: categories: Re: \phi for the golden ratio? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: cat-dist@mta.ca Precedence: bulk Date: Sun, 06 Jun 2004 09:30:05 -0300 Status: O X-Status: X-Keywords: X-UID: 5 [note from moderator: this will be the last of this thread...] > So far, I have only met three real or complex numbers with universally > accepted one-letter symbols: \pi, e, i. Have I missed something? What about "r" (pronounced "rev"), denoting 2*pi, in the archaic but still widely understood phrase "33 rpm record"? A shame the Greeks chose pi rather than rev, for I think the latter is more fundamental. Paul From rrosebru@mta.ca Sun Jun 6 09:34:43 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Sun, 06 Jun 2004 09:34:43 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BWwpT-0005GS-00 for categories-list@mta.ca; Sun, 06 Jun 2004 09:32:47 -0300 Date: Sat, 5 Jun 2004 22:51:09 -0400 (EDT) From: Michael Makkai To: categories@mta.ca Subject: categories: preprint: The multitopic omega-category of all multitopic omega-categories (revised) Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 6 I have posted a revised version of my 1999 paper "The multitopic omega-category of all multitopic omega-categories" on my web-site http://www.math.mcgill.ca/makkai/ . I have left the old version on the site too for the time being. Michael Makkai From rrosebru@mta.ca Sun Jun 6 09:34:43 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Sun, 06 Jun 2004 09:34:43 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BWwo4-0005D5-00 for categories-list@mta.ca; Sun, 06 Jun 2004 09:31:20 -0300 From: Martin Escardo MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16576.29130.267057.241786@gargle.gargle.HOWL> Date: Fri, 4 Jun 2004 13:57:46 +0100 To: categories@mta.ca Subject: categories: synthetic topology X-Mailer: VM 7.07 under 21.4 (patch 8) "Honest Recruiter" XEmacs Lucid Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 7 This is to advertise the monograph "Synthetic topology of data types and classical spaces" http://www.cs.bham.ac.uk/~mhe/papers/entcs87.pdf (or dvi or ps) which will appear soon in volume 83 of ENTCS. NB. (1) For those of you who attended my PSSL talk in Cambridge: The topos-theoretic treatment of synthetic topology has not been included here. (2) This monograph supersedes a preliminary version which was previously available from my web page. Martin Escardo -- Summary (not as in the monograph) This monograph consists of three parts divided in 6+5+2 chapters. Part II (topology of classical spaces) applies the exponential law for function spaces, with the aid of the Sierpinski space, to develop the core of classical topology in a transparent (and constructive) way. Mathematicians can start from this part, and even confine their attention to it. Part I (topology of data types) emulates the second and stands on its own. It starts from the well known ideas that (1) the Sierpinski space plays the role a data type of results of semidecisions or observations, and (2) the notion of continuous map has that of computable or programmable map as a computational counterpart. The development of the synthetic topology of data types offered in this part is operational rather than denotational. This is to emphasize that the topology is there, even in the case of sequential programming languages, independently of which denotational model one favours (if any). Part III starts by unifying the first and the second, again following well known ideas, and then develops further applications to computation, this time with the aid of denotational semantics. In particular, the Tychonoff theorem for countably many factors is invoked to establish termination of a certain program (in the simply-typed lambda calculus with natural numbers and fixed-point recursion). In turn, termination of the program implies the Tychonoff theorem for countably many second countable compact spaces. ------------------------------------------------------------------------ http://www.cs.bham.ac.uk/~mhe/papers/entcs87.pdf ------------------------------------------------------------------------ From rrosebru@mta.ca Sun Jun 6 09:34:43 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Sun, 06 Jun 2004 09:34:43 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BWwnT-0005Bn-00 for categories-list@mta.ca; Sun, 06 Jun 2004 09:30:43 -0300 Message-Id: <200406040923.i549N5s06268@synaphai.kurims.kyoto-u.ac.jp> X-Authentication-Warning: synaphai.kurims.kyoto-u.ac.jp: hassei@localhost didn't use HELO protocol To: categories@mta.ca Subject: categories: TLCA 05 Call for Papers Date: Fri, 04 Jun 2004 18:23:05 +0900 From: Hasegawa Masahito Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 8 TLCA'05 CALL FOR PAPERS Seventh International Conference on Typed Lambda Calculi and Applications (TLCA '05) Nara, Japan 21-23 April 2005 (Colocated with RTA as RDP '05) http://www.kurims.kyoto-u.ac.jp/rdp05/tlca/ The TLCA series of conferences serves as a forum for presenting original research results that are broadly relevant to the theory and applications of typed lambda calculi and related systems. The following list of topics is non-exhaustive: * Typed and untyped lambda-calculi as models of computation. * Proof-theory: Natural deduction, sequent calculi, cut elimination and normalization. Propositions as types, linear logic and proof nets. * Types: Subtypes, dependent types, type inference, polymorphism, types for security. * Semantics: Denotational semantics, game semantics, realizability, categorical models. * Programming languages: Foundations of functional and object-oriented programming, proof search, logic programming, type checking. * Implementation: Abstract machines, parallel execution, optimal reduction, program optimization. * Computer-aided reasoning. The programme of TLCA'05 will consist of three invited talks and about 25 papers selected from original contributions. Accepted papers will be published as a volume of Springer Lecture Notes in Computer Science series. [http://www.springer.de/comp/lncs/index.html] Submissions: ------------ The submitted papers should describe original work and should allow the Programme Committee to assess the merits of the contribution: in particular references and comparisons with related work should be included. Submission of material already published or submitted to other conferences with published proceedings is not allowed. Papers should not exceed 15 pages in Springer LNCS format. An abstract (ASCII text) of no more than 150 words should be sent separately at least a week before the paper submission deadline. All submissions should be sent by e-mail to tlca05@mimuw.edu.pl Important dates: ---------------- Authors are required to submit a paper title and a short abstract at least a weak before the paper submission deadline. All deadlines below are at 24:00 Central European time (GMT+1). Titles and abstracts due: October 25, 2004 Paper submission deadline: November 2, 2004 Notification: December 22, 2004 Final versions due: January 31, 2005 Accepted papers should be prepared according to Springer LNCS guidelines as described in http://www.springer.de/comp/lncs/authors.html. Final versions must include all source files. Further information is available from the conference web page http://www.kurims.kyoto-u.ac.jp/rdp05/tlca/ Inquiries concerning submissions and programme should be addressed to tlca05@mimuw.edu.pl. Inquiries concerning the conference organization and participation should be sent to tlca05org@kurims.kyoto-u.ac.jp TLCA Steering Committee: ------------------------ Samson. Abramsky, Oxford, chair Henk Barendregt, Nijmegen Mariangiola Dezani-Ciancaglini, Turin Roger Hindley, Swansea Martin Hofmann, Munich TLCA 05 Programme Committee: ---------------------------- Thorsten Altenkirch, University of Nottingham Stefano Berardi, University of Turin Adriana Compagnoni, Stevens Institute of Technology, Hoboken Herman Geuvers, Nijmegen University Andy Gordon, Microsoft Research, Cambridge Fritz Henglein, Copenhagen University Martin Hofmann, LMU Munich Assaf J. Kfoury, Boston University Atsushi Ohori, JAIST, Tatsunokuchi Laurent Regnier, IML Marseille Pawel Urzyczyn, Warsaw University, chair Marek Zaionc, Jagiellonian University, Cracow TLCA 05 Organizing Committee: ----------------------------- Masahito Hasegawa, Kyoto, chair Ryu Hasegawa, Tokyo Mitsu Okada, Keio Masahiko Sato, Kyoto Masako Takahashi, ICU ------------------------------------------------------------------------------ From rrosebru@mta.ca Tue Jun 8 17:49:31 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 08 Jun 2004 17:49:31 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BXnSW-0001GS-00 for categories-list@mta.ca; Tue, 08 Jun 2004 17:44:36 -0300 Message-ID: <40C5DC9C.3040507@bath.ac.uk> Date: Tue, 08 Jun 2004 16:34:52 +0100 From: "David J. Pym" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6b) Gecko/20031205 Thunderbird/0.4 X-Accept-Language: en-us, en MIME-Version: 1.0 To: categories@mta.ca Subject: categories: New OUP Monograph: Reductive Logic and Proof-search. Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 9 Readers of these lists may be interested in the following new monograph in OUP's Oxford Logic Guides series (number 45): Reductive Logic and Proof-search: Proof Theory, Semantics, and Control by David Pym and Eike Ritter. http://www.oup.co.uk/isbn/0-19-852633-4 also linked from http://www.bath.ac.uk/~cssdjp Contents: Preface Foreword by Lincoln Wallen 1 Deductive Logic, Reductive Logic, and Proof-search 2 Lambda-calculi for Intuitionistic and Classical Proofs 3 The Semantics of Intuitionistic and Classical Proofs 4 Proof Theory for Reductive Logic 5 Semantics for Reductive Logic 6 Intuitionistic and Classical Proof-search and Their Semantics References Index With thanks, David Pym -- Prof. David J. Pym Telephone: +44 (0)1 225 38 3246 Professor of Logic & Computation Facsimile: +44 (0)1 225 38 3493 University of Bath Email: d.j.pym@bath.ac.uk Bath BA2 7AY, England, U.K. Web: http://www.bath.ac.uk/~cssdjp From rrosebru@mta.ca Fri Jun 11 09:57:53 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Fri, 11 Jun 2004 09:57:53 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BYlYg-0005ak-00 for categories-list@mta.ca; Fri, 11 Jun 2004 09:54:58 -0300 Date: Thu, 10 Jun 2004 14:05:58 +0100 Message-Id: <200406101305.i5AD5wfT024840@aberdour.inf.ed.ac.uk> X-Authentication-Warning: aberdour.inf.ed.ac.uk: als set sender to als+lics-junk@inf.ed.ac.uk using -f To: LICS List From: Alex Simpson Subject: categories: LICS 2004 - Call for Participation Reply-To: als+lics-replies-ignored@dcs.ed.ac.uk Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 10 The deadline for early registration for LICS 2004 is *June 15, 2004*. ------------------------------------------------------------------------ CALL FOR PARTICIPATION Nineteenth Annual IEEE Symposium on LOGIC IN COMPUTER SCIENCE (LICS 2004) July 13th - 17th, 2004, Turku, Finland http://www.lfcs.informatics.ed.ac.uk/lics/ The LICS Symposium is an annual international forum on theoretical and practical topics in computer science that relate to logic in a broad sense. For registration visit http://www.math.utu.fi/ICALP04/registration.html The deadline for early registration is June 15, 2004. Collocated events: ICALP'04 will be collocated with LICS'04; for details see http://www.math.utu.fi/ICALP04/. Invited Speakers: The following distinguished speakers will give invited talks at LICS 2004: Samson Abramsky (U. of Oxford), Robert Harper (Carnegie Mellon University), Alexander Razborov (IAS, Princeton, and Steklov Math. Inst., Moscow), Davide Sangiorgi (U. di Bologna), Igor Walukiewicz (U. Bordeaux), and Mihalis Yannakakis (Stanford U.). For full program visit LICS website http://www.lfcs.informatics.ed.ac.uk/lics/ Program Committee: Rajeev Alur, U. of Pennsylvania Andrew Appel, Princeton U. Albert Atserias, UPC, Barcelona Franz Baader, Dresden U. Samuel Buss, U. of California, San Diego Roberto Di Cosmo, U. de Paris VII Gilles Dowek, Ecole Polytechnique, Paris Harald Ganzinger, MPI, Saarbruecken (chair) Martin Hofmann, LMU Muenchen Achim Jung, U. of Birmingham Kim Larsen, Aalborg U. Leonid Libkin, U. of Toronto Rocco de Nicola, U. di Firenze Damian Niwinski, Warsaw U. Prakash Panangaden, McGill U., Montreal Albert Rubio, UPC, Barcelona Vitaly Shmatikov, SRI International Moshe Vardi, Rice U., Houston Helmut Veith, TU Wien Andrei Voronkov, U. of Manchester Conference Chair: Lauri Hella Department of Math., Stat., and Phil. Kanslerinrinne 1 33014 University of Tampere, Finland Email: lauri.hella@uta.fi Workshops Chair: Phil Scott, U. of Ottawa Email: phil@site.uottawa.ca Publicity Chair: Alex Simpson, U. of Edinburgh Email: Alex.Simpson@ed.ac.uk General Chair: Phokion G. Kolaitis, UC Santa Cruz Email: kolaitis@cse.ucsc.edu Organizing Committee: S. Abramsky, A. Broder, E. Clarke, A. Felty, H. Ganzinger, H. Gabow, J. Halpern, L. Hella, U. Kohlenbach, P. Kolaitis (chair), D. Leivant, G. Longo, H. Mairson, A. Middeldorp, J. Mitchell, M. Nielsen, P. Panangaden, G. Plotkin, F. Pfenning, P. Scott, R. Shore, A. Simpson, I.A. Stewart. Advisory Board: Y. Gurevich, C. Kirchner, D. Kozen, U. Martin, L. Pacholski, V. Pratt, A. Scedrov, M.Y. Vardi, G. Winskel. Sponsorship: The symposium is sponsored by the IEEE Technical Committee on Mathematical Foundations of Computing in cooperation with the Association for Symbolic Logic, and the European Association for Theoretical Computer Science. From rrosebru@mta.ca Wed Jun 16 18:14:45 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 16 Jun 2004 18:14:45 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1Bahci-0003VS-00 for categories-list@mta.ca; Wed, 16 Jun 2004 18:07:08 -0300 Mime-Version: 1.0 (Apple Message framework v618) Content-Transfer-Encoding: 7bit Message-Id: <059095AA-BEE2-11D8-A8D3-000A279156EE@cs.man.ac.uk> Content-Type: text/plain; charset=US-ASCII; format=flowed To: categories@mta.ca From: Barney Hilken Subject: categories: Pullback & coproduct of toposes Date: Tue, 15 Jun 2004 16:38:17 +0100 Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 11 I don't have access to a decent library at the moment, and I can't afford a copy of the Elephant myself, so can anyone let me know: In the category of toposes and geometric morphisms, under what conditions is coproduct stable under pullback? Any reasonable conditions on the toposes or the morphisms would be helpful, but the more general, the better. Thanks, Barney. From rrosebru@mta.ca Wed Jun 16 18:26:03 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 16 Jun 2004 18:26:03 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1Bahre-0004LF-00 for categories-list@mta.ca; Wed, 16 Jun 2004 18:22:34 -0300 Date: Wed, 16 Jun 2004 18:10:26 -0300 (ADT) From: Bob Rosebrugh To: categories Subject: categories: interruption Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 12 The categories moderator will be out of email contact June 18-29, 2004. Postings submitted to Categories during that period will be distributed June 30. Best wishes, Bob Rosebrugh From rrosebru@mta.ca Tue Jun 29 13:30:48 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 29 Jun 2004 13:30:48 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfLRB-0003d4-00 for categories-list@mta.ca; Tue, 29 Jun 2004 13:26:25 -0300 From: "Steve Lack" To: Subject: categories: RE: Pullback & coproduct of toposes Date: Tue, 22 Jun 2004 09:41:13 +1000 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit In-Reply-To: <059095AA-BEE2-11D8-A8D3-000A279156EE@cs.man.ac.uk> Importance: Normal Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 13 >-----Original Message----- >From: cat-dist@mta.ca [mailto:cat-dist@mta.ca]On Behalf Of Barney Hilken >Sent: Wednesday, 16 June 2004 1:38 AM >To: categories@mta.ca >Subject: categories: Pullback & coproduct of toposes > > >I don't have access to a decent library at the moment, and I can't >afford a copy of the Elephant myself, so can anyone let me know: > >In the category of toposes and geometric morphisms, under what >conditions is coproduct stable under pullback? > Answer: always. Let f:E-->S+S' be a morphism of toposes. Identify S+S' with the product of the categories S and S'. Then in S+S' the terminal object (1,1) is a coproduct (1,0)+(0,1). Now apply the inverse image functor f* to obtain a decomposition 1=X_1+X_2 of the terminal object 1 in E. By extensivity of E, then, the category E is equivalent to the product E/X_1 x E/X_2; in other words, the topos E is the coproduct of the toposes E/X_1 and E/X_2. (Where E/X_1 and E/X_2 are of course the pullbacks along f of the injections S-->S+S' and S'-->S+S'.) This argument is contained in Marta Bunge & Stephen Lack, Van Kampen theorems for toposes, Adv. Math. 179:291-317, 2003. where it is seen as part of the fact that the 2-category of toposes is extensive. Steve Lack. From rrosebru@mta.ca Tue Jun 29 13:30:48 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 29 Jun 2004 13:30:48 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfLRx-0003hn-00 for categories-list@mta.ca; Tue, 29 Jun 2004 13:27:13 -0300 Mime-Version: 1.0 (Apple Message framework v618) Content-Type: text/plain; charset=WINDOWS-1252; delsp=yes; format=flowed Message-Id: <2833CFCD-C5E6-11D8-B96E-000A95D05E0E@itu.dk> Content-Transfer-Encoding: quoted-printable From: Thomas Hildebrandt Subject: categories: CMCIM 2004 Workshop: Final Call for (Short) Papers and Participation Date: Thu, 24 Jun 2004 15:55:31 +0200 To: Categories list Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 14 FINAL CALL FOR (Short) PAPERS AND PARTICIPATION (Deadline July 1st): 3rd WORKSHOP ON: CATEGORICAL METHODS FOR CONCURRENCY, INTERACTION AND MOBILITY (CMCIM 2004), AUGUST 11, 2004 (www.itu.dk/research/theory/ctcs2004/cmcim.html) IT University of Copenhagen (ITU) Copenhagen, Denmark www.itu.dk - affiliated with the 10th conference in Category Theory and Computer =20= Science (CTCS 2004) ,August 12th-14th, and Graduate Student Summer School in Category Theory and Computer =20 Science, August 9th-11th. ------------------------------------------------------------------------=20= ------------------------------------------ NEW: - Extended workshop submission deadline: July 1st - Accepted papers and abstracts for invited talks for CTCS available at =20= www.itu.dk/research/theory/ctcs2004/ ------------------------------------------------------------------------=20= ------------------------------------------- We invite submissions of short, extended abstracts (less than 5 pages) =20= for an informal half-day workshop on Categorical Methods in =20 Concurrency, Interaction and Mobility. The workshop has previously been =20= held in connection with CONCUR 2002 and CONCUR 2003. There will be no formal proceedings of the workshop, informal =20 proceedings will be distributed at the workshop. Thus, accepted material may be published elsewhere at a later date. Submissions may present status reports, recent results, challenges, or =20= work in progress Topics of interest include: =95 categorical algebras of processes =95 categorical methods in game semantics and geometry of = interaction =95 categorical models of term/graph rewriting or rewriting = logic =95 Chu spaces =95 coalgebras, bialgebras, coinduction =95 comparing models of concurrency =95 enriched categories of processes =95 interaction categories =95 bigraphs =95 presheaf semantics Workshop PARTICIPATION IS FREE, but REQUIRES REGISTRATION before 1st of =20= July, by SENDING AN EMAIL to hilde@itu.dk, containing =20 `CMCIM2004-registration' in the subject, and your full name and =20 affiliation in the body. Submissions should be sent before July 1st, as PostScript or PDF file =20= to: hilde@itu.dk, containing `CMCIM-submission' in the subject, and in =20= the body the full names of the author(s), title, and a text-only =20 abstract. CMCIM 2004 Workshop Organizers: Thomas Hildebrandt Alexander Kurz More information and registration at: http://www.itu.dk/research/theory/ctcs2004/cmcim.html --------------------------------------- SPONSORSHIP The conference and summer school are APPSEM-II events, and are as the =20= workshop sponsored by the FIRST graduate school (www.first.dk) and the Department of Theoretical Computer Science at IT University of =20 Copenhagen (http://www.itu.dk/Internet/sw648.asp). From rrosebru@mta.ca Tue Jun 29 13:30:48 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 29 Jun 2004 13:30:48 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfLTB-0003lA-00 for categories-list@mta.ca; Tue, 29 Jun 2004 13:28:29 -0300 Mime-Version: 1.0 (Apple Message framework v618) Content-Type: text/plain; charset=ISO-8859-1; delsp=yes; format=flowed Message-Id: <922D31AE-C5B9-11D8-B96E-000A95D05E0E@itu.dk> Content-Transfer-Encoding: quoted-printable To: Categories list From: Thomas Hildebrandt Subject: categories: CTCS '04: Accepted papers and Final Call for Participation Date: Thu, 24 Jun 2004 10:36:21 +0200 X-Mailer: Apple Mail (2.618) X-Virus-Scanned: by amavisd-new at itu.dk Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 15 FINAL CALL FOR PARTICIPATION (Deadline July 1st) 10th CONFERENCE ON CATEGORY THEORY AND COMPUTER SCIENCE (CTCS'04) AUGUST 12-14, 2004 www.itu.dk/research/theory/ctcs2004/ and GRADUATE STUDENT SUMMER SCHOOL AUGUST 9-11, 2004 www.itu.dk/research/theory/ctcs2004/summerschool.html and 3rd WORKSHOP ON CATEGORICAL METHODS FOR CONCURRENCY, INTERACTION AND MOBILITY (CMCIM 2004) AUGUST 11, 2004 www.itu.dk/research/theory/ctcs2004/cmcim.html IT University of Copenhagen (ITU) Copenhagen, Denmark www.itu.dk ------------------------------------------------------------------------=20= --- NOTE: The registration deadline at July 1st is approaching NEW: List of accepted papers for CTCS NEW: Abstracts of invited talks for CTCS ------------------------------------------------------------------------=20= --- Important Dates: * April 16th, 2004: CTCS Submission deadline (closed) * June 1st, 2004: CTCS Notification of authors of accepted papers * July 1st, 2004: Submission of abstracts for CMCIM Workshop =20 (extended) * July 1st, 2004: CTCS Registration (and special hotel rates) = deadline ------------------------------------------------------------------------=20= ---- CTCS'04 is the 10th Conference on Category Theory and Computer Science, with the purpose to advance the foundations of computing using the =20 tools of category theory. Invited Speakers for the CTCS 2004 Conference: * Francois Bergeron (Queb=E9c) * Martin Hyland (Cambridge) * Robin Milner (Cambridge) * Andrew Pitts (Cambridge) * Thomas Streicher (Darmstadt) Abstracts at: =20 http://www.itu.dk/research/theory/ctcs2004/InvitedTalks.html Typical topics at CTCS include category-theoretic aspects of the =20 following: coalgebras and computing concurrent and distributed systems constructive mathematics declarative programming and term rewriting domain theory and topology foundations of computer security linear logic modal and temporal logics models of computation program logics, data refinement, and specification programming language semantics type theory Previous conferences have been held in Guildford (Surrey), Edinburgh =20 (twice), Manchester, Paris, Amsterdam, Cambridge, S. Margherita Ligure (Genova), =20= and Ottawa. More information and registration form at: http://www.itu.dk/research/theory/ctcs2004/ ---------------------------------------------------------------------- CTCS 2004 PhD SUMMER SCHOOL The summer school is aimed at both graduate and undergraduate students, =20= with basic knowledge of category theory. The school will offer mini-courses (5 =20 lectures each) in: * Stone Duality, Coalgebras, and Modal Logic (Alexander Kurz) * Game Semantics (Guy McCusker) * Operational Semantics (Pawel Sobocinski) * Categorical Models for Concurrency (Thomas Hildebrandt) More information and registration at: http://www.itu.dk/research/theory/ctcs2004/summerschool.html -------------------------------------------------------------------- CMCIM 2004 WORKSHOP (short abstract deadline: July 1st) In between the summer school and the CTCS conference, August 11th, there will be an informal half-day workshop on Categorical Methods in Concurrency, Interaction and Mobility. The workshop has previously been held in connection with CONCUR 2002 and CONCUR 2003. We invite submissions of short extended abstracts (less than 5 pages), presenting status reports, recent results, challenges or work in progress. There will be no formal proceedings of the workshop, informal proceedings will be distributed at the workshop. Thus, accepted material may be published elsewhere at a later date. Workshop participation is FREE, but requires registration before 1st of July. Submissions should be sent before 1st of July (extended). More information and registration at: http://www.itu.dk/research/theory/ctcs2004/cmcim.html ----------------------------------------------------------------- Organisation: CTCS 2004 PROGRAMME COMMITTEE: Lars Birkedal, Chair (IT University of Copenhagen) Marcelo Fiore (University of Cambridge) Masahito Hasegawa (Kyoto University) Bart Jacobs (University of Nijmegen) Ugo Montanari (University of Pisa) Valeria de Paiva (Palo Alto Research Center) Dusko Pavlovic (Kestrel Institute) John Power (University of Edinburgh) Edmund Robinson (Queen Mary, University of London) Peter Selinger (University of Ottawa) CTCS ORGANIZING COMMITTEE E. Moggi, Chair, (Genova) S. Abramsky (Oxford) P. Dybjer (Chalmers) B. Jay (Sydney) A. Pitts (Cambridge) CTCS 2004 LOCAL ORGANIZING COMMITTEE C. Butz T. Hildebrandt A.L. Moerk CMCIM 2004 Workshop Organizers: Thomas Hildebrandt Alexander Kurz --------------------------------------- SPONSORSHIP The conference and summer school are APPSEM-II events, sponsored by the FIRST graduate school (www.first.dk) and the Department of Theoretical Computer Science at the IT University of =20 Copenhagen (http://www.itu.dk/Internet/sw648.asp). From rrosebru@mta.ca Tue Jun 29 13:31:12 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 29 Jun 2004 13:31:12 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfLVk-0003vx-00 for categories-list@mta.ca; Tue, 29 Jun 2004 13:31:08 -0300 Date: Fri, 25 Jun 2004 18:15:52 -0600 (MDT) From: "M. Healy" To: categories@mta.ca Subject: categories: preprint: Neural Networks, Knowledge and Cognition... Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 16 A technical report on a categorical model of the semantics of neural networks is now available on the Dspace archive in the collection 2004. To access it, go to the University of New Mexico site at https://repository.ece.unm.edu/dspace/ and search on http://hdl.handle.net/1928/33 . Here's an abstract: Neural Networks, Knowledge, and Cognition: A Mathematical Semantic Model Based upon Category Theory, by M. J. Healy and T. P. Caudell Category theory can be applied to mathematically model the semantics of cognitive neural systems. We discuss semantics as a hierarchy of concepts, or symbolic descriptions of items sensed and represented in the connection weights distributed throughout a neural network. The hierarchy expresses subconcept relationships, and in a neural network it becomes represented incrementally through a Hebbian-like learning process. The categorical semantic model described here explains the learning process as the derivation of colimits and limits in a concept category. It explains the representation of the concept hierarchy in a neural network at each stage of learning as a system of functors and natural transformations, expressing knowledge coherence across the regions of a multi-regional network equipped with multiple sensors. The model yields design principles that constrain neural network designs capable of the most important aspects of cognitive behavior. Please let me know right away if there are any problems. I'll warmly receive any questions or comments. - Mike From rrosebru@mta.ca Tue Jun 29 13:33:20 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 29 Jun 2004 13:33:20 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfLXj-00043K-00 for categories-list@mta.ca; Tue, 29 Jun 2004 13:33:11 -0300 Date: Tue, 29 Jun 2004 17:52:49 +0200 (CEST) From: Message-Id: <200406291552.RAA22755@kodder.math.uu.nl> To: categories@mta.ca Subject: categories: preprint: Filtered colimits in the effective topos X-Sun-Charset: US-ASCII X-Virus-Scanned: by amavisd-new at math.uu.nl Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 17 A 7-page paper entitled Filtered colimits in the effective topos can be downloaded from: http://www.math.uu.nl/people/jvoosten/effcolim.ps.gz Abstract: we are concerned with the problem whether there is a small full dense subcategory in the effective topos (which would give a nice embedding of Eff into a sheaf topos). Since this topos has enough projectives, we may assume that such a category consists of the \lambda-small projectives for some cardinal \lambda. Basically, there are two theorems: 1. For \lambda regular, uncountable: the \lambda -small projectives are dense, precisely if the constant objects functor \nabla :Sets --> Eff preserves \lambda-filtered colimits. 2. \nabla : Sets --> Eff does not preserve \omega _1-filtered colimits (hence, by 1., the countable projectives are not dense). Jaap van Oosten From rrosebru@mta.ca Wed Jun 30 18:29:16 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 30 Jun 2004 18:29:16 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfmYv-00012F-00 for categories-list@mta.ca; Wed, 30 Jun 2004 18:24:13 -0300 Date: Tue, 29 Jun 2004 18:01:49 +0100 (BST) From: "Prof. Peter Johnstone" To: categories@mta.ca Subject: categories: Re: Pullback & coproduct of toposes In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-DPMMS-Scan-Signature: e26bfe9cfc17be7b1a279ab952802df2 Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 18 On Tue, 22 Jun 2004, Steve Lack wrote: > >I don't have access to a decent library at the moment, and I can't > >afford a copy of the Elephant myself, so can anyone let me know: > > > >In the category of toposes and geometric morphisms, under what > >conditions is coproduct stable under pullback? > > > > Answer: always. Let f:E-->S+S' be a morphism of toposes. Identify S+S' > with the product of the categories S and S'. Then in S+S' the terminal > object (1,1) is a coproduct (1,0)+(0,1). Now apply the inverse image > functor f* to obtain a decomposition 1=X_1+X_2 of the terminal object 1 > in E. By extensivity of E, then, the category E is equivalent to the > product E/X_1 x E/X_2; in other words, the topos E is the coproduct > of the toposes E/X_1 and E/X_2. (Where E/X_1 and E/X_2 are of course > the pullbacks along f of the injections S-->S+S' and S'-->S+S'.) > > This argument is contained in > > Marta Bunge & Stephen Lack, Van Kampen theorems for toposes, Adv. Math. > 179:291-317, 2003. > > where it is seen as part of the fact that the 2-category of toposes > is extensive. > ... and it is (of course) in the Elephant: page 402, remark following Lemma B3.4.1. Peter Johnstone From rrosebru@mta.ca Wed Jun 30 18:29:16 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 30 Jun 2004 18:29:16 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfmZn-00016X-00 for categories-list@mta.ca; Wed, 30 Jun 2004 18:25:07 -0300 Reply-To: From: "Noson Yanofsky" To: "categories@mta. ca" Subject: categories: Questions on dinatural transformations. Date: Tue, 29 Jun 2004 13:19:46 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 19 Hello, Two quick questions: a) It is well known that there is no vertical composition of dinatural transformations. How about horizontal composition? i.e. Given S,S':C^op x C---->B T,T':C^op x C ----> B^op U,U':B^op x B --->A \alpha: S--->S' dinat \alpha': T--->T' dinat and \beta: U--->U' dinat is there a \beta \circ (\alpha',\alpha) and is it dinat? It should be. But I can not seem to find the right definition. How about if we restrict to a nice category of moduals for a nice algebra over a nice field? Does that help? I was hoping that the category of small categories, functors and dinat transformations should be a graph-category (a category enriched over graphs) but am having a hard time finding what the composition is. Did someone write on these things? b) Also, I was wondering if anyone ever wrote about quasi-dinatural transformations. Those are dinats where the target category is a 2-category and the hexagon commutes up to a two cell. They show up in something I am working on. But they are very painful. Has anyone worked on such things? Any thoughts? All the best, Noson Yanofsky From rrosebru@mta.ca Wed Jun 30 18:29:16 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 30 Jun 2004 18:29:16 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BfmaI-000181-00 for categories-list@mta.ca; Wed, 30 Jun 2004 18:25:38 -0300 Message-ID: <20040630174359.50998.qmail@web52607.mail.yahoo.com> Date: Wed, 30 Jun 2004 10:43:59 -0700 (PDT) From: Galchin Vasili Subject: categories: Grothendieck bio? To: cat group MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 20 Hello, Does anybody know of a Grothendieck biography? For me many times it is helpful to read a bio to the historical development of a person's work. Thanks in advance, Bill Halchin From rrosebru@mta.ca Fri Jul 2 07:47:32 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Fri, 02 Jul 2004 07:47:32 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BgLWR-0005RV-00 for categories-list@mta.ca; Fri, 02 Jul 2004 07:43:59 -0300 Date: Wed, 30 Jun 2004 21:15:52 -0400 (EDT) From: Phil Scott To: Subject: categories: Re: Questions on dinatural transformations. In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: cat-dist@mta.ca Precedence: bulk Status: O X-Status: X-Keywords: X-UID: 21 In general, the naive horizontal merging of dinaturals fails to be dinatural. This is discussed in the article "Functorial Polymorphism" by Bainbridge, Freyd, Scedrov and me (Theoretical Computer Science 1990, pp. 35-64). Several counterexamples are given there. For example, in a cartesian closed category of domains or CPO's, consider a dinatural family Y_A: A^A --> A (e.g. in domains, let Y_A = the least fixed point operator). If you were able to compose this with the "polymorphic identity" dinat id_A: 1---> A^A (i.e. a dinat from constant functor 1 to (-) ==> (-) where id_A = the transpose of the identity on A), then the category would be degenerate (proved in BFSS, Appendix A.4). Of course, if the middle diamond (of an attempted merging of two dinat families) is a pullback or pushout, then merging works. (see BFSS, Fact 1.2). Re vertical merging, some things can be said quite generally: e.g BFSS, Propn. 1.3. For various generalizations, see Peter Freyd's paper "Structural Polymorphism" (in TCS, 1993, pp.107-129). Soloviev has also discussed compositionality of dinats in several articles in JPAA. Philip Scott On Tue, 29 Jun 2004, Noson Yanofsky wrote: > Hello, > > Two quick questions: > > a) It is well known that there is no vertical > composition of dinatural transformations. > How about horizontal composition? > > i.e. Given > S,S':C^op x C---->B > T,T':C^op x C ----> B^op > U,U':B^op x B --->A > \alpha: S--->S' dinat > \alpha': T--->T' dinat > and > \beta: U--->U' dinat > > is there a \beta \circ (\alpha',\alpha) and is it dinat? > It should be. But I can not seem to find the right definition. > > How about if we restrict to a nice category of moduals for a nice algebra > over a nice field? Does that help? > > I was hoping that the category of small categories, functors and > dinat transformations > should be a graph-category (a category enriched over graphs) but > am having a hard time > finding what the composition is. Did someone write on these > things? > > > b) Also, I was wondering if anyone ever wrote about > quasi-dinatural transformations. Those > are dinats where the target category is a 2-category and the > hexagon commutes up to a > two cell. They show up in something I am working on. But they are > very painful. Has anyone > worked on such things? > > > Any thoughts? > > All the best, > Noson Yanofsky > > > > From rrosebru@mta.ca Fri Jul 2 07:47:32 2004 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Fri, 02 Jul 2004 07:47:32 -0300 Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1BgLVJ-0005N9-00 for categories-list@mta.ca; Fri, 02 Jul 2004 07:42:49 -0300 Date: Wed, 30 Jun 2004 18:58:33 -0400 (EDT) From: Robert Seely To: Subject: categories: Re: Grothendieck bio? In-Reply-To: <20040630174359.50998.qmail@web52607.mail.yahoo.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: cat-dist@mta.ca Precedence: bulk Status: RO X-Status: X-Keywords: X-UID: 22 Don't know of any "standard biography", though you could check out some links on-line (the Triples home page lists the following: http://www.fermentmagazine.org/rands/recoltes1.html http://www.grothendieck-circle.org/ http://modular.fas.harvard.edu/sga/ http://www.math.jussieu.fr/~maltsin/groth/Derivateurs.html (though the last two are reprints of papers etc)). In addition, a French publication "Bourbaki" (pub by Pour La Science - the French edition of Scientific American) mentions him as part of that group - and has a rather nice photo of him and his child. Good luck! -= rags =- On Wed, 30 Jun 2004, Galchin Vasili wrote: > Hello, > > Does anybody know of a Grothendieck biography? For > me many times it is helpful to read a bio to the > historical development of a person's work. > > Thanks in advance, Bill Halchin > > --