October 1999 - Categories - categories.org.au

Cfp: Realizability Semantics and Applications (MSCS special issue)
by Lars Birkedal 11 Dec '99

11 Dec '99

Call for Papers Special Issue of Mathematical Structures in Computer Science (MSCS) on Realizability Semantics and Applications Editors: L. Birkedal, J. van Oosten, G. Rosolini, D.S. Scott There has been recently a reawaking of interest in many aspects of realizability interpretations -- especially as regards semantics of type theories for constructive reasoning and semantics of programming languages. But, the details of realizability can be quite technical, and therefore a tutorial workshop on realizability and appliations was held in June/July 1999 in Trento, Italy. The workshop contained both tutorial lectures and also contributed research talks, see http://www.cs.cmu.edu/afs/cs/user/birkedal/www/realizability-workshop/ for an overview. A special issue of the journal Mathematical Structures in Computer Science (MSCS) will be devoted to papers on realizability semantics and applications. The volume will contain the tutorial presentations given by invited speakers at the realizability workshop in Trento. We now also solicit contributions of research papers on realizability and applications for the special MSCS volume. Everyone is invited to contribute a paper (i.e., not only researchers who contributed a paper to the realizability workshop). Papers will be refereed to the usual high standards of MSCS. Instruction to Authors Authors are invited to submit full original research papers. Papers should be submitted via email to wr99(a)athena.disi.unige.it as a postscript file, or by mailing a hard copy to Lars Birkedal School of Computer Science Carnegie Mellon University 5000 Forbes Avenue Pittsburgh, PA 15213, USA before January 1, 2000. Important Dates Submission Deadline: January 1, 2000.

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function spaces
by Martin Escardo 18 Nov '99

18 Nov '99

Dear Comprox and Categories members, Here is a short note that Reinhold Heckmann and I have written. Your comments are welcome, as always. On function spaces in topology ------------------------------ It is the purpose of this expository note to provide a self-contained, elementary and brief development of the fact that the exponentiable topological spaces are precisely the core-compact spaces. The only prerequisite is a basic knowledge of topology (continuous functions, product topology and compactness). We hope that teachers and students of topology will find this useful. As far as we know, there is no such development available in the literature. Although there are one or two embellishments, our methods are certainly not original. We briefly discuss more advanced treatments in the introduction. ------------------------------------------------------------------- http://www.dcs.st-and.ac.uk/~mhe/papers/exponentiablespaces.ps.gz http://www.dcs.st-and.ac.uk/~mhe/papers/exponentiablespaces.dvi.gz http://www.dcs.st-and.ac.uk/~mhe/papers/exponentiablespaces.ps http://www.dcs.st-and.ac.uk/~mhe/papers/exponentiablespaces.dvi ------------------------------------------------------------------- Best regards, Martin & Reinhold

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graph classifiers
by John Stell 29 Oct '99

29 Oct '99

The classifier, \Omega, for subgraphs has two nodes and five edges. The bi-Heyting algebra of subgraphs of a graph has two complement like operators, $\neg$ and $\suppl$. These satisfy $G \meet \neg G = \bot$ and $G \join \suppl G = \top$. One of these ($\neg$) arises from an endomorphism of $\Omega$ but the other does not. The operations $\neg$ and $\suppl$ are nicely dual in some ways but only one can be described in terms of $\Omega$. Is there some kind of explanation for this? It is possible to find a graph $\Delta$ and to describe a given subgraph as a morphism to $\Delta$ and to obtain $\suppl$ as an endomorphism of $\Delta$. But although there is a morphism from $\Delta$ to $\Omega$, we don't get $\neg$ via any endomorphism of $\Delta$. $\Delta$ has four nodes corresponding to a classification of nodes as (1) out (2) in and with all incident edges in (3) in and with all incident edges out (4) in and with some incident edges in and some out. Of course this is analogous to the edges in $\Omega$. There are four kinds of edge identified by $\Omega$ (working with a version of $\Omega$ for undirected graphs) (1) in (2) out and with all incident nodes out (3) out and with all incident nodes in (4) out and with some incident nodes out and some in. Is there a formal sense in which $\Delta$ and $\Omega$ are dual to each other? Is there a better way to view $\suppl$ as coming from some kind of classifier of graphs? Does anyone have any comments or suggestions for relevant literature? John Stell -------------------------------------------------------------------- Dr John Stell Department of Computer Science email john(a)cs.keele.ac.uk Keele University Keele, Staffordshire, telephone +44 1782 584083 ST5 5BG U. K. fax +44 1782 713082 http://www.keele.ac.uk/depts/cs/Staff/Homes/John/homepage.html --------------------------------------------------------------------

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COCOON 2000
by Vladimir Estivill-Castro 25 Oct '99

25 Oct '99

Apologies if you receive multiple copies of this message. COCOON'2OOO --- Preliminary Call for Papers --- Sixth Annual International Computing and Combinatorics Conference July 26-28, 2000, Bondi Beach , Sydney , Australia The Sixth Annual International Computing and Combinatorics Conference, COCOON'2000, will be held in Bondi Beach , Sydney , Australia July 26--28, 2000 (a few weeks before the XXVII Olympics, September 15 -- October 1 ). The conference aims to provide a forum for researchers in theoretical computer science. Original research papers in the areas of algorithms, theory of computation, computational complexity, and combinatorics related to computing are solicited. In additional to theoretical results, submissions that report substantial results in experimental and applied research are encouraged. Typical, but not exclusive, topics of interest include: -- algorithms and data structures -- automata, languages and logic -- combinatorics related to algorithms and complexity -- complexity theory -- computational algebra, biology, geometry, and number theory -- computational learning theory and knowledge discovery -- cryptography and database theory -- graph drawing and information visualization -- graph theory, communication networks, and optimization -- parallel and distributed computing Submissions to the conference this year will again be conducted electronically. Authors should send a PostScript file of a paper (in English) to cocoon2000(a)cse.unsw.edu.au by February 8, 2000. A submission guideline will be given on our home page: http://www.cs.newcastle.edu.au/~cocoon2000 Alternatively, authors unable to access e-mail may send 6(six) hard copies of their papers to: Xuemin Lin - COCOON'2000 School of Computer Science and Engineering University of New South Wales Sydney, NSW 2052, Australia. e-mail: lxue(a)cse.unsw.edu.au A paper should start with the title of the paper, each author's name, affiliation, e-mail address, and a short summary of the main results. The paper should provide sufficient detail to allow the Program Committee to evaluate its validity, quality, and relevance to the conference. The length of the paper should not exceed 10 pages (using 11 point or larger font, with ample margins all around). If necessary, authors may include a clearly marked appendix that will be read at the discretion of the Program Committee. An abstract of the paper must be submitted electronically by February 1, 2000. Authors will be notified of acceptance or rejection by March 30, 2000. A camera-ready copy of each accepted paper will be required by April 26, 2000. The proceedings of the conference will be published by Springer-Verlag in the Lecture Notes in Computer Science series, and will be available for distribution at the conference. The Hao Wang award will be given to the best paper (details will be given on our home page). We also introduce an award for the best paper from a young researcher (at most 3 years since PhD). Program Committee Co-Chairs =========================== Ding-Zhu Du (U. of Minnesota, USA) Peter Eades (Newcastle, Australia) Xuemin Lin (New South Wales, Australia) Conference Co-Chairs ==================== Vladimir Estivill-Castro (Newcastle, Australia) Arun Sharma (New South Wales, Australia) Program Committee ================= David Avis (McGill, Canada), Jianer Chen (Texas A&M, USA), Francis Chin (Hong Kong U, Hong Kong), Vladimir Estivill-Castro (Newcastle, Australia), George Havas (UQ, Australia), Hiroshi Imai (Tokyo, Japan), Tao Jiang (UC Riverside, USA), Richard Karp (UC Berkeley, USA), Michael Juenger (Cologne, Germany), D. T. Lee (Academia Sinica, Taiwan), Bernard Mans (Macquarie U., Australia), Brendan McKay (ANU, Australia), Maurice Nivat (Universitie de Paris VII, France), Takeshi Tokuyama (Tohoku, Japan), Roberto Tamassia (Brown, USA), Jie Wang (UNC Greensboro, USA), Shmuel Zaks (Technion, Israel), Louxin Zhang (NUS, Singapore), Shuzhong Zhang (CUHK, Hong Kong), Binhai Zhu (City U Hong Kong, Hong Kong) Invited Speakers ================ - Christos H. Papadimitriou (University of California, Berkeley) - Richard Brent (Oxford University Computing Laboratory) Important Dates ============== -- Submission of Abstracts: February 1, 2000 -- Submission of Papers: February 8, 2000. -- Notification of Acceptance: March 30, 2000. -- Final Version: April 26, 2000. -- Conference: July 26-28, 2000 . Location ======== The conference will be held at the Swiss-Grand Hotel in Bondi Beach, Sydney, Australia. Further Information =================== Please contact cocoon2000(a)cse.unsw.edu.au for further information. Sponsors ======== - University of New South Wales - University of Newcastle - Computer Science Association of Australasia

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CP for CMCS'2000
by Horst Reichel 25 Oct '99

25 Oct '99

C A L L F O R P A P E R S for the WORKSHOP ON COALGEBRAIC METHODS IN COMPUTER SCIENCE (CMCS'2000) Scope State-based dynamical systems as found throughout computing science are traditionally described as transition systems or certain kinds of automata. During the last decade, it has become increasingly clear that such systems can be captured uniformly as so-called ``coalgebras'' (which are the formal dual of algebras). Coalgebra is beginning to develop into a field of its own, with its own proof-methods (involving bisimulations and invariants). This workshop will be devoted to both an introduction to basic coalgebraic notions and techniques, and also to some recent advances in the theory of coalgebras. We are looking for participants and contributed talks to this informal workshop on both the theory and the use of coalgebras in computer science. The workshop will consist of two days, preceding the ETAPS conference (25-26 March, 2000) at the Technical University of Berlin. More information regarding submissions is given below. The scope of the meeting includes the following themes: - the theory of coalgebras (including set theoretic and categorical approaches); - coalgebras as computational and semantical models (for programming languages, dynamic systems, etc.); - coalgebras in (functional, object-oriented, concurrent) programming; - coalgebras and data types; - (coinductive) definition and proof principles for coalgebras (with bisimulations or invariants); - coalgebras and (hidden-sorted) algebras; - coalgebraic specification and verification; - coalgebras and (modal) logic Organization: Bart Jacobs (Nijmegen), Horst Reichel(Dresden), Jan Rutten (CWI, Amsterdam) and Larry Moss (Bloomington, IN). Program Committee: H. Peter Gumm (Marburg), Bart Jacobs (Nijmegen), Ugo Montanari (Pisa), Larry Moss (Bloomington, IN), Ataru T. Nakagawa (Tokyo), John Power (Edinburgh), Horst Reichel (Dresden), Jan Rutten (CWI, Amsterdam). Submissions The following dates are important for submission to the ENTCS volume. - 3 January 2000: deadline for submissions. - 11 February 2000: notification of acceptance. - 3 March 2000: final version. - 25-26 March 2000: workshop, where a printed version of the ENTCS issue will be available for participants. - (25 March - 2 April, 2000: ETAPS conference). The ideal submission is not longer than 20 pages, and gives a clear exposition of the relevant ideas. It can be sent by email to: Horst Reichel, or by ordinary mail to:

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John Isbell's Progress
by John Duskin 23 Oct '99

23 Oct '99

I thought many on the list might like to know about John Isbell's remarkable progress even over the last weekend. He is regaining bodily strength rapidly. More importantly, he is beginning to read again with some pleasure, and to converse and write (!) with his usual intelligence and precision. And wit: Yesterday, I tried to help him move to a more comfortable position but did not succeed and remarked, "Close but no cigar!". He immediately asked if I had heard about a reporter's interview with Clinton's other tell- all friend, Gennifer Flowers. I hadn't. Seems she was asked if her relationship with the president had been like that of Miss Lewinski. The reply was, "Close, but no cigar". Best regards, Jack P.S. If any one wants to contact John by e-mail, for the moment, just sent it to me and note that it is for him. I will make sure that he gets it.

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CL2000: 2nd call for papers
by femke＠cs.vu.nl 23 Oct '99

23 Oct '99

*** apologies for multiple copies *** First International Conference on Computational Logic, CL2000 Imperial College, London, UK 24th to 28th July, 2000 2nd call for papers CL2000 is the first conference in a major new series of annual international conferences bringing together the various communities of researchers who have a common interest in Computational Logic. CL2000 is collocating with the following conferences: DOOD2000: 6th Int'l Conference on Rules and Objects in Databases ILP2000: 10th Int'l Workshop on Inductive Logic Programming LOPSTR2000: 10th Int'l Workshop on Logic-based Program Synthesis and Transformation CL2000 will include seven streams covering various subfields of computational logic, each with its own separate Program Committee: - Database Systems (DOOD2000) - Program Development (LOPSTR2000) - Knowledge Representation and Non-monotonic Reasoning - Automated Deduction: Putting Theory into Practice - Constraints - Logic Programming: Theory and Extensions - Logic Programming: Implementations and Applications The last three streams effectively constitute the former ICLP conference series that will be now integrated into CL2000. ILP2000 will be collocating as a separate conference. Papers on all aspects of the theory, implementation, and application of Computational Logic are invited, where Computational Logic is to be understood broadly as the use of logic in Computer Science. Provisional deadlines: Papers must be submitted by 1 February, 2000 Authors will be notified of acceptance/rejection by 1 May, 2000 Camera-ready versions must be received by 1 June, 2000 Further information is available at the conference web site: http://www.doc.ic.ac.uk/cl2000

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exponentials in Set^Set
by Clare Martin 21 Oct '99

21 Oct '99

Please could somebody tell me whether exponentials exist in the functor category Set^Set, and if so, how to define them?

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SUMMER SCHOOL ON MATHEMATICS OF PROGRAM CONSTRUCTION
by Roy L. Crole 19 Oct '99

19 Oct '99

=================================================================== FIRST ANNOUNCEMENT =================================================================== SUMMER SCHOOL AND WORKSHOP ON ******************************************* * ALGEBRAIC AND CO-ALGEBRAIC METHODS IN * * THE MATHEMATICS OF PROGRAM CONSTRUCTION * ******************************************* Lincoln College, Oxford, UK, 10th to 14th April 2000 This school specifically aims to equip mathematicians embarking on a PhD degree with the knowledge and expertise to contribute to current research in computing science. It is also of interest to other PhD students and lecturers with an active interest in the mathematics of program construction. The school will consist of the following intensive courses together with a one-day workshop at which participants will be given the opportunity to present their own research. LECTURERS Peter Aczel (University of Manchester): Initial Algebras and Final Coalgebras: The Categorical Perspective Roland Backhouse (University of Nottingham): Fixpoint Calculus and Galois Connections Richard Bird (Oxford University): The Algebra of Programming Jeremy Gibbons (Oxford University): Calculational Properties of Folds and Unfolds Bart Jacobs (Nijmegen Catholic University): Coalgebras and Coinduction Burghard von Karger (University of Kiel): Temporal Algebra Hilary Priestley (Oxford University): Lattices and Order DEADLINES For financial support: 31st January 2000 For registration: 11th February 2000 ORGANIZERS Roland Backhouse (University of Nottingham) Roy Crole (University of Leicester) Jeremy Gibbons (Oxford University) Preliminary information can be found at the School home page http://www.comlab.ox.ac.uk/oucl/research/areas/ap/acmmpc/ REGISTRATION To register, complete the form below, and deliver it by one of the following methods: * By email, to acmmpc-reg(a)comlab.ox.ac.uk * By fax, to +44 1865 273839 (mark "for the attention of Jeremy Gibbons") * By post, to ACMMPC, c/o Jeremy Gibbons, Oxford University Computing Laboratory, Wolfson Building, Parks Road, Oxford OX1 3QD, UK. If you have any further questions, please email acmmpc-info(a)comlab.ox.ac.uk, or contact the organizers by fax or post. Please note that places on the School are limited, and early registration is advisable. ------------- cut here -------------------------------------------- ******************************************* * ALGEBRAIC AND CO-ALGEBRAIC METHODS IN * * THE MATHEMATICS OF PROGRAM CONSTRUCTION * * REGISTRATION FORM * ******************************************* Lincoln College, Oxford, UK, 10th to 14th April 2000 FIRST NAME ..... LAST NAME(S) ..... ADDRESS ..... EMAIL ..... TELEPHONE ..... STATUS (please select: edit email or tick hard-copy) * EPSRC PhD student ..... * Other PhD student ..... * non PhD student ..... ROOM (please select: edit email or tick hard-copy) * single ensuite room, full board: 80.41 ..... * single standard room, full board: 75.18 ..... * shared twin standard room, full board: 72.87 ..... * single standard room, half board: 53.57 ..... * single standard room, bed-and-breakfast only: 39.82 ..... * special dietary requirements ..... (Y/N) (please specify) All prices are per night, and are subject to VAT. "Half board" includes bed, breakfast and evening meal; "full board" also includes morning coffee, lunch, and afternoon tea. EDUCATIONAL BACKGROUND (please provide a short description of your mathematical and computing background; a few sentences will do) ADDITIONAL INFORMATION (please give details of any other information you wish to supply)

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CATOP2000
by Claude Auderset 18 Oct '99

18 Oct '99

Conference C A T O P 2 0 0 0 (Second announcement) to be held at the University of Fribourg (Switzerland), 4-6 July, 2000 (a satellite conference of 3ECM, Barcelona). TOPIC: It is the aim of this conference to discuss categorical topological methods that are likely to be mathematically important in the next century. Furthermore, on Thursday afternoon resp. evening, we shall celebrate the seventieth birthday of Professor Heinrich Kleisli (Fribourg). Tentative titles of the eight invited two hour lectures: A. ARHANGEL'SKII (Moscow, Russia): Topological semigroups. M. BARR (Montreal, Canada): The *-autonomous category of Mackey spaces. MARIA M. CLEMENTINO (Coimbra, Portugal): Closure operators. KATHRYN P. HESS (Lausanne, Switzerland): Model categories in algebraic topology. R. LOWEN (Antwerp, Belgium): Approach spaces. HILARY A. PRIESTLEY (Oxford, England): Duality theory. D. PUMPLUEN (Hagen, Germany): Convex sets and Saks spaces (A paradigmatic case of applied category theory). S. WATSON (York, Canada): How to construct counterexamples in general and set-theoretic topology usefully with pullbacks. SHORT COMMUNICATIONS: Persons interested in giving a short communication are kindly asked to send a one page abstract of their talk by ordinary (air)mail to Prof. Heinrich Kleisli, Department of Mathematics, University of Fribourg, 1700 Fribourg, Switzerland, before April 1, 2000. Please note however that the programme of the congress mainly consists of the afore-mentioned 8 invited lectures (of 2 times 50 minutes each) and allows only a restricted number of (about 8-10) short communications (of 20 minutes each); if necessary, the scientific committee of the conference will have to select among the suggested short communications the most suitable ones. Each participant who wishes to give a short communication will be informed by May 1, 2000, whether his or her talk is part of the final programme of the congress. ACCOMMODATION: The hotels (and student residences) are located near the railway station. The prices are as follows (breakfast included): Single room: 90 sFr. up, Double room: 140 sFr. up. Student residence: Single room (~45 sFr.) Double room (~35 sFr./pers.) TRAVELLING TO FRIBOURG: Intercity trains connect Fribourg with the international airports of Geneva and Zurich. Talks will take place in the Chemistry Building, Perolles-site of the University of Fribourg, close to the centre of the town. Further information about the congress (e.g. maps) can be obtained via its homepage: www.unifr.ch/math/catop2000 REGISTRATION: A participation fee of 100 sFr. (Swiss francs) will be paid by each participant. The ticket for the banquet on Thursday night costs additional 80 sFr. Please indicate in the registration form below how many tickets for the banquet you need. The deadline for paying the registration fee and tickets is April 10, 2000. Please make money orders payable to Banque Cantonale, CATOP2000, Inst.Math., CH-1700 Fribourg, (CCP 17-49-3), account-no 25'01'016.390-09, b.cl. 768. The registration desk will open on Tuesday morning at 8.00. Email facilities will be available to participants during the conference. The organizers strongly recommend electronic preregistration via our homepage mentioned above. Persons who have no access to Internet also may fill in the preregistration form given below and send it to one of the following addresses of the congress: Email: catop2000(a)unifr.ch (Air)mail: Catop2000, Department of Mathematics, University of Fribourg, 1700 Fribourg, Switzerland We are looking forward to meeting you in Fribourg. The organizing committee of CATOP 2000: Ernst Ruh (Fribourg), Hans-Peter Kuenzi (Bern), Claude Auderset (Fribourg). ========================================================================= Preregistration Form (before 10th April, 2000) ------------------------------------------------------------------------- Registration Details: Family name (please print): First name: Affiliation: Mailing address (if different): Email: Fax: Arrival date: Departure date: I shall arrive with accompanying persons. I need tickets for the banquet. Visa support: I need an official invitation: yes/no accommodation needed: yes/no accommodation in student residence: single/ double room in hotel: single / double room Additional remarks: --------------------------------

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