November 2006 - Categories - categories.org.au

Foundations?
by F W Lawvere 03 Sep '10

03 Sep '10

Down with "Foundations"! Up with algebra! Dear Friends, Presumably I am among those who are being "vilified" as "lovers of categories as foundation". By avoiding any precise definition, such a formulation might appeal to the widespread justified boredom induced by the past hundred years of "foundations as justification". Whenever I used the word "foundation" in my writings over the past forty years, I have explicitly rejected that reactionary use of the term and instead used the definition implicit in the work of my teachers Truesdell and Eilenberg. Namely, an important component of mathematical practice is the careful study of historical and contemporary analysis, geometry, etc. to extract the essential recurring concepts and constructions; making those concepts and constructions (such as homomorphism, functional, adjoint functor, etc.) explicit provides powerful guidance for further unified development of all mathematical subjects, old and new. What is the primary tool for such summing up of the essence of ongoing mathematics? Algebra! Nodal points in the progress of this kind of research occur when, as is the case with the finite number of axioms for the metacategory of categories, all that we know so far can be expressed in a single sort of algebra. I am proud to have participated with Eilenberg, Mac Lane, Freyd, and many others, in bringing about the contemporary awareness of Algebra as Category Theory Had it not been for the century of excessive attention given to the alleged possibility that mathematics is inconsistent, with the accompanying degradation of the F-word, we would still be using it in the sense known to the general public: the search for what is "basic". We, who supposedly know the explicit algebra of homomorphisms, functionals, etc. are long remiss in our duty to find ways to utilize those concepts also in guiding high school calculus. Best wishes, Bill Bibliography: - The Category of Categories as a Foundation for Mathematics, La Jolla conference 1965, Springer (1966) - Adjointness in Foundations, Dialectica, (1969), to be reprinted in TAC - Foundations and Applications: Axiomatization and Education, Bulletin of Symbolic Logic, (2003) vol 9, pp 213-224 - Sets for Mathematics, w/ Bob Rosebrugh, Cambridge Univ. Press, (2003) ************************************************************ F. William Lawvere Mathematics Department, State University of New York 244 Mathematics Building, Buffalo, N.Y. 14260-2900 USA Tel. 716-645-6284 HOMEPAGE: http://www.acsu.buffalo.edu/~wlawvere ************************************************************

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A question about extensive categories
by Jiri Adamek 14 Dec '06

14 Dec '06

Dear colleagues, Does anyone know whether every extensive and locally finitely presentable category fulfils the following condition: For every omega op-chain of coproduct injections i_n: A_n+1 -> A_n with all A_n finitely presentable some i_n is an isomorphism. We need this for investigating iterative monads in such categories, and we have not managed to prove it, nor to find a counterexample. Thanks, Jiri Adamek, Stefan Milius and Jiri Velebil xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx alternative e-mail address (in case reply key does not work): J.Adamek(a)tu-bs.de xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

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PSSL 85 in Nice - first announcement
by cat-dist＠mta.ca 01 Dec '06

01 Dec '06

PSSL 85 in Nice - first announcement It is proposed to hold the 85th meeting of the Peripatetic Seminar on Sheaves and Logic in Nice during the weekend of 24/25 March 2007. We expect to have some money available to support students' and postdocs' attendance at the conference. If you are interested please write to Eugenia Cheng. For those unfamiliar with PSSLs, they are a long-running series of meetings, usually held on a weekend at a university somewhere in Europe. They are fairly informal, and presentations of work in progress are quite acceptable. The name is a (charming) historical relic: talks cover all aspects of category theory, not just sheaves and logic. Further details of the arrangements will be announced by early February and posted at the following website: http://math.unice.fr/~eugenia/pssl85 . In the meantime if you have any questions please do not hesitate to contact me. Regards, Eugenia Cheng --- Universite de Nice Sophia-Antipolis eugenia(a)math.unice.fr http://math.unice.fr/~eugenia

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IEEE Computer Security Foundations 2007 - call for papers
by Andrei Sabelfeld 28 Nov '06

28 Nov '06

[New: CSFW is dropping its "W" and possibly becoming a symposium already in 2007 (subject to approval by the IEEE Computer Society).] Call For Papers 20th IEEE Computer Security Foundations Workshop (CSF) Venice, Italy, July 6 - 8, 2007 Sponsored by the Technical Committee on Security and Privacy of the IEEE Computer Society CSF20 website: http://www.dsi.unive.it/CSFW20/ CSF home page: http://www.ieee-security.org/CSFWweb/ CSF CFP: http://www.cs.chalmers.se/~andrei/CSF07/cfp.html The IEEE Computer Security Foundations Workshop (CSF) series brings together researchers in computer science to examine foundational issues in computer security. Over the past two decades, many seminal papers and techniques have been presented first at CSF. The CiteSeer Impact page (http://citeseer.ist.psu.edu/impact.html ) lists CSF as 38th out of more than 1200 computer science venues in impact (top 3.11%) based on citation frequency. There is a possibility of upgrading CSF to an IEEE symposium already in 2007. New theoretical results in computer security are welcome. Also welcome are more exploratory presentations, which may examine open questions and raise fundamental concerns about existing theories. Panel proposals are welcome as well as papers. Possible topics include, but are not limited to: Authentication Access control Distributed systems Information flow Trust and trust security Security management Security for mobile protocols Security models computing Anonymity and Intrusion Executable content Privacy detection Decidability and Electronic voting Data and system complexity Network security integrity Formal methods for Resource usage Database security security control Language-based security Proceedings published by the IEEE Computer Society Press will be available at the workshop, and selected papers will be invited for submission to the Journal of Computer Security. Important Dates Papers due: Monday, February 5, 2007 Panel proposals due: Thursday, March 15, 2007 Notification: Monday, March 26, 2007 Camera-ready papers: Friday, April 27, 2007 Workshop: July 6-8, 2007 Program Committee Tuomas Aura, Microsoft Research, UK Michael Backes, Saarland University, Germany Bruno Blanchet, ENS, France Iliano Cervesato, Carnegie Mellon University, Qatar George Danezis, K.U.Leuven, Belgium Herve Debar, France Telecom, France Riccardo Focardi, University of Venice, Italy Dieter Gollmann, Hamburg University of Technology, Germany Carl A. Gunter, University of Illinois at Urbana-Champaign, USA Joshua Guttman, MITRE, USA Masami Hagiya, University of Tokyo, Japan Jonathan Herzog, Naval Postgraduate School, USA Ninghui Li, Purdue University, USA Cathy Meadows, NRL, USA Jonathan Millen, MITRE, USA John Mitchell, Stanford University, USA Flemming Nielson, Technical University of Denmark, Denmark Riccardo Pucella, Northeastern University, USA Andrei Sabelfeld, Chalmers University of Technology, Sweden (chair) Pierangela Samarati, University of Milan, Italy Ravi Sandhu, George Mason University and TriCipher, USA Andre Scedrov, University of Pennsylvania, USA Vitaly Shmatikov, University of Texas at Austin, USA Geoffrey Smith, Florida International University, USA Steve Zdancewic, University of Pennsylvania, USA Workshop Location The 20th IEEE Computer Security Foundations Workshop will be held in the facilities of Venice International University, located on the island of San Servolo, about 10 minutes by water ferry from the Piazza San Marco. Instructions for Participants Although submission is open to anyone, attendance is by invitation. All authors of accepted papers are invited to attend, and authors are required to ensure that at least one will be present. This year's meeting location will allow us to invite more participants than previous years. Submission Instructions Submitted papers must not substantially overlap with papers that have been published or that are simultaneously submitted to a journal or a conference with published proceedings. Papers should be submitted in Postscript or Portable Document Format (PDF). Papers submitted in a proprietary word processor format such as Microsoft Word cannot be considered. At least one coauthor of each accepted paper is required to attend CSF to present the paper. Papers may be submitted using the two-column IEEE Proceedings style available for various document preparation systems at IEEE-CS Press. Papers in this style should be at most 12 pages long, not counting bibliography and well-marked appendices. Alternatively, papers can be in Springer LLNCS style. In LLNCS style papers must be at most 20 pages long excluding the bibliography and well-marked appendices. Committee members are not required to read appendices, and so the paper must be intelligible without them. Papers not adhering to the page limits will be rejected without consideration of their merits. The paper submission website will be open in January 2007. Proposals for panels are also welcome. They should be no more than five pages in length and should include possible panelists and an indication of which of those panelists have confirmed a desire to participate. They should be submitted by email to the program chair by March 15, 2007. A session of five-minute talks was successful in the last two years, so we are likely to have one again in 2007. Abstracts will be solicited in May. There are PDF and HTML versions of this call for papers at http://www.cs.chalmers.se/~andrei/CSF07/cfp.html . For further information contact: +-----------------------------------------------------------------+ |General Chair |Program Chair |Publications | | | |Chair | |-----------------------+------------------ +-------------------| |Riccardo Focardi |Andrei Sabelfeld |Jonathan Herzog | |Universita di |Chalmers |Computer Science | |Venezia, Informatica |University of |Naval Postgraduate | |Via Torino 155 |Technology |School | |I-30172 Mestre (Ve), |41296 Gothenburg, |Monterey CA, 93943 | |Italy |Sweden |USA | |+39 041 2348 438 |+46 31 772 1000 |+1 831 656 3990 | |focardi AT dsi.unive.it|andrei AT chalmers.se|jcherzog AT nps.edu| +-----------------------------------------------------------------+

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Implicit algebraic operations
by Todd Wilson 28 Nov '06

28 Nov '06

I was going through some of my old notes today and came across investigations I had done several years ago on implicit operations in Universal Algebra. These are definable partial operations on algebras that are preserved by all homomorphisms. Here are two examples: (1) Pseudocomplements in distributive lattices. Given a <= b <= c in a distributive lattice, there is at most one b' such that b /\ b' = a and b \/ b' = c. Because lattice homomorphisms preserve these inequalities and equations, the uniqueness of pseudocomplements implies that, when they exist, they are also preserved by homomorphisms. (2) Multiplicative inverses in monoids. Similarly, given an element m in a monoid (M, *, 1), there is at most one element m' such that m * m' = 1 and m' * m = 1. It follows that inverses, when they exist, are also preserved by monoid homomorphisms. Now, the investigation of these partial operations gets one quickly into non-surjective epimorphisms, dominions in the sense of Isbell, algebraic elements in the sense of Bacsich, implicit partial operations in the sense of Hebert, and other topics. Some of the references that I know about are listed below. My question is this: Does a definitive treatment of this phenomenon in "algebraic" categories exist? Are there still some mysteries/open problems? REFERENCES PD Bacsich, "Defining algebraic elements", JSL 38:1 (Mar 1973), 93-101. PD Bacsich, "An epi-reflector for universal theories", Canad. Math. Bull. 16:2 (1973), 167-171. PD Bacsich, "Model theory of epimorphisms", Canad. Math. Bull. 17:4 (1974), 471-477. JR Isbell, "Epimorphisms and dominions", Proc. of the Conference on Categorical Algebra, La Jolla, Lange and Springer, Berlin 1966, 232-246. JM Howie and JR Isbell, "Epimorphisms and dominions, II", J. Algebra, 6 (1967), 7-21. JR Isbell, "Epimorphisms and Dominions, III", Amer. J Math. 90:4 (Oct 1968), 1025-1030. M Hebert, "Sur les operations partielles implicites et leur relation avec la surjectivite des epimorphismes", Can. J. Math. 45:3 (1993), 554-575. M Hebert, "On generation and implicit partial operations in locally presentable categories", Appl. Cat. Struct. 6:4 (Dec 1998), 473-488. -- Todd Wilson A smile is not an individual Computer Science Department product; it is a co-product. California State University, Fresno -- Thich Nhat Hanh

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CFP: Symposium on Logical Foundations of Computer Science LFCS07
by Phil Scott 27 Nov '06

27 Nov '06

************************************************************************ SYMPOSIUM ON LOGICAL FOUNDATIONS OF COMPUTER SCIENCE (LFCS'07) Revised Call for papers NOTE THE REVISED SUBMISSION DEADLINE New York City, June 4 - 7, 2007 URL: www.cs.gc.cuny.edu/lfcs07 Email: lfcs07(a)gmail.com * Purpose. The LFCS series provides an outlet for the fast-growing body of work in the logical foundations of computer science, e.g., areas of fundamental theoretical logic related to computer science. The LFCS schedule is consistent with LICS and CSL timelines. * Theme. Constructive mathematics and type theory; logical foundations of programming; logical aspects of computational complexity; logic programming and constraints; automated deduction and interactive theorem proving; logical methods in protocol and program verification; logical methods in program specification and extraction; domain theory logics; logical foundations of database theory; equational logic and term rewriting; lambda and combinatory calculi; categorical logic and topological semantics; linear logic; epistemic and temporal logics; intelligent and multiple agent system logics; logics of proof and justification; non-monotonic reasoning; logic in game theory and social software; logic of hybrid systems; distributed system logics; system design logics; other logics in computer science. * All submissions must be done electronically (15 pages, pdf, 12pt) via http://www.easychair.org/LFCS07/ * Submission deadline: December 11, 2006 * Notification: January 11, 2007 * Steering Committee. Anil Nerode (Cornell, General Chair); Stephen Cook (Toronto); Dirk van Dalen (Utrecht); Yuri Matiyasevich (St.Petersburg); John McCarthy (Stanford); J. Alan Robinson (Syracuse); Gerald Sacks (Harvard); Dana Scott (Carnegie-Mellon). * Program Committee. Samson Abramsky (Oxford); Sergei Artemov (New York City, PC Chair); Matthias Baaz (Vienna); Lev Beklemishev (Moscow); Andreas Blass (Ann Arbor); Lenore Blum (CMU); Samuel Buss (San Diego); Thierry Coquand (Go"teborg); Ruy de Queiroz (Recife, Brazil); Denis Hirschfeldt (Chicago); Bakhadyr Khoussainov (Auckland); Yves Lafont (Marseille); Joachim Lambek (McGill); Daniel Leivant (Indiana); Victor Marek (Kentucky); Anil Nerode (Cornell, General LFCS Chair); Philip Scott (Ottawa); Anatol Slissenko (Paris); Alex Simpson (Edinburgh); V.S. Subrahmanian (Maryland); Michael Rathjen (Leeds); Alasdair Urquhart (Toronto).

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Re: NUMDAM progress
by jim stasheff 21 Nov '06

21 Nov '06

**************************************************************** * archive: http://listserv.albany.edu:8080/archives/emj.html * **************************************************************** Wow! yes, especially the Seminaire H Cartan jim Larry Siebenmann wrote: > **************************************************************** > * archive: http://listserv.albany.edu:8080/archives/emj.html * > **************************************************************** > > *** NUMDAM progress > > > Dear Friends, > > Digitization continues, particularly in Europe. > You will find much good mathematics not easily accessible > otherwise at : > > http://archive.numdam.org/numdam-bin/browse > > Here is the impressive list of Journals etc. now scanned. > I was particularly pleased to find the Cartan Seminar > and numerous cousins. > > > JOURNAUX > > Annales de la facult'e des sciences de Toulouse 1887-1936 1937-2002 > Annales de l'institut Fourier 1949-2000 > Annales de l'institut Henri Poincar'e 1930-1964 > Annales de l'institut Henri Poincar'e (A) Physique th'eorique 1964-1983 1984-1999 > Annales de l'institut Henri Poincar'e (B) Probabilit'es et Statistiques 1964-2000 > Annales de l'institut Henri Poincar'e (C) Analyse non lin'eaire 1984-2000 > Annales math'ematiques Blaise Pascal 1994-2002 > Annales de Gergonne 1810-1832 > Annales Scientifiques de l''Ecole Normale Sup'erieur 1864-1905 1906-1952 1953-2000 > Annales de l'universit'e de Grenoble 1945-1948 > Bulletin de la Soci'et'e Math'ematique de France 1872-1922 1923-1972 1973-2000 > Compositio Mathematica 1935-1983 1984-1996 > Journ'ees 'equations aux d'eriv'ees partielles 1974-2003 > M'emoires de la Soci'et'e Math'ematique de France 1964-1977 1978-1992 1992-2000 > Publications Math'ematiques de l'IH'ES 1959-1979 1980-2000 > Revue de Statistique Appliqu'ee 1953-2004 > > > S'EMINAIRES > > Cahiers du s'eminaire d'histoire des math'ematiques 1980-1991 > Groupe de travail d'analyse ultram'etrique 1973-1988 > Groupe d''etude d'alg`ebre 1975-1977 > S'eminaire Samuel. Alg`ebre commutative 1966-1968 > S'eminaire Brelot-Choquet-Deny. Th'eorie du potentiel 1957-1972 > S'eminaire Choquet. Initiation `a l'analyse 1962-1977 > S'eminaire Claude Chevalley 1956-1959 > S'eminaire Dubreil. Alg`ebre et th'eorie des nombres 1947-1975 > S'eminaire Delange-Pisot-Poitou. Th'eorie des nombres 1959-1979 > S'eminaire Ehresmann. Topologie et g'eom'etrie diff'erentielle 1957-1965 > S'eminaire A. Grothendieck 1957-1957 > S'eminaire Henri Cartan 1948-1964 > S'eminaire Janet. M'ecanique analytique et m'ecanique c'eleste 1957-1963 > S'eminaire Lelong. Analyse 1957-1967 > S'eminaire L. de Broglie. Th'eories physiques 1954-1958 > S'eminaire Schwartz 1953-1961 > S'eminaire Sch"utzenberger 1969-1970 > S'eminaire Paul Kr'ee 1974-1978 > S'eminaire de probabilit'es de Strasbourg 1967-2002 > S'eminaire "Sophus Lie" 1954-1956 > Groupe d''etude de th'eories stables 1977-1982 > Groupe d''etude en th'eorie analytique des nombres 1984-1986 > > (Please excuse the approximative ASCII accents > I'm on an ascii terminal) > > Laurent S.

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9 research assistant positions available
by Till Mossakowski 16 Nov '06

16 Nov '06

9 research assistant positions (most of them TVL 13, approx. € 35,000 to € 50,000 p.a. gross) available, at Transregional Collaborative Research Center SFB/TR 8 Spatial Cognition: Reasoning, Action, Interaction at the Universities of Bremen and Freiburg, Germany The positions are in general concerned with interdisciplinary long-term research in Spatial Cognition. Some of the positions may be of interest to the readers of this list, because formal methods, logic and category theory are used. For details, see http://www.sfbtr8.uni-bremen.de/openpositions.html (in particular, projects I1, I3 and I4) -- Till Mossakowski Office: Phone +49-421-218-64226 DFKI Lab Bremen Cartesium Fax +49-421-218-9864226 Robert-Hooke-Str. 5 Enrique-Schmidt-Str. 5 till(a)tzi.de D-28359 Bremen Room 2.051 http://www.tzi.de/~till

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Morgan-Phoa Mathematics Workshop
by Ross Street 12 Nov '06

12 Nov '06

Anyone interested in category theory and related topics who can be in Canberra (Australia) at the end of November is welcome to join in the Morgan-Phoa Mathematics Workshop to be held at the Australian National University. I have set up a little Web page which I will update as the event approaches: <http://www.math.mq.edu.au/~street/MorganPhoa.html>. Ross

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CfP: Special issue I&C on SOS
by Rob van Glabbeek and Peter Mosses 11 Nov '06

11 Nov '06

Call for Papers: Special Issue of Information & Computation on Structural Operational Semantics Aim: Structural operational semantics (SOS) provides a framework for giving operational semantics to programming and specification languages. A growing number of programming languages from commercial and academic spheres have been given usable semantic descriptions by means of structural operational semantics. Because of its intuitive appeal and flexibility, structural operational semantics has found considerable application in the study of the semantics of concurrent processes. Moreover, it is becoming a viable alternative to denotational semantics in the static analysis of programs, and in proving compiler correctness. Recently, structural operational semantics has been successfully applied as a formal tool to establish results that hold for classes of process description languages. This has allowed for the generalisation of well-known results in the field of process algebra, and for the development of a meta-theory for process calculi based on the realization that many of the results in this field only depend upon general semantic properties of language constructs. This special issue aims at documenting state-of-the-art research, new developments and directions for future investigation in the field of structural operational semantics. Specific topics of interest include (but are not limited to): * programming languages * process algebras * higher-order formalisms * rule formats for operational specifications * meaning of operational specifications * comparisons between denotational, axiomatic and operational semantics * compositionality of modal logics with respect to operational specifications * congruence with respect to behavioural equivalences * conservative extensions * derivation of proof rules from operational specifications * software tools that automate, or are based on, SOS. Papers reporting on applications of SOS to software engineering and other areas of computer science are welcome. This special issue is an outgrowth of the series of SOS workshops, which started in 2004, and serves in part as a opportunity to publish the full versions of the best papers presented at SOS 2006. However, papers that were not presented at SOS 2006 are equally welcome, and all submissions will be refereed and subjected to the same quality criteria, meeting the standards of Information and Computation. Papers submitted to the special issue must contain original material that has not previously been published, and parallel submission for publication elsewhere is not allowed. However, an extended abstract or short version of the paper may be submitted for presentation at the SOS 2007 workshop, which will take place before the publication of the special issue. PAPER SUBMISSION: We solicit unpublished papers reporting on original research on the general theme of SOS. Papers should take the form of a dvi, postscript or pdf file. We recommend following Elsevier's instructions at http://authors.elsevier.com/JournalDetail.html?PubID=622844 and using LaTeX2e with documentclass elsart. IMPORTANT DATES: * Submission of tentative title and abstract: 15 December 2006 * Submission of full paper: 15 February 2006 CONTACT and submission address: sos2006(a)cs.stanford.edu EDITORS of this special issue: Rob van Glabbeek National ICT Australia Locked Bag 6016 University of New South Wales Sydney, NSW 1466 Australia Peter D. Mosses Department of Computer Science Swansea University Singleton Park Swansea SA2 8PP United Kingdom

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