Date: Mon, 1 Apr 1996 13:20:06 --100 From: Enrico Vitale <vitale@lma.univ-littoral.fr> 61st PERIPATETIC SEMINAR ON SHEAVES AND LOGIC Universite' du Littoral - Dunkerque - France Saturday/Sunday, June 8/9, 1996 The 61st meeting of the PERIPATETIC SEMINAR ON SHEAVES AND LOGIC will be held in Dunkerque over the week-end of 8-9 june 1996. We wait for participants on Friday evening or Saturday morning. Lectures will start at 9:45 a.m. As usual, there will be morning and afternoon sessions on Saturday and a morning session on Sunday. Talks will be held in the University building, 1 quai de Freycinet, at the 2nd floor. REGISTRATION: there is a registration form attached to this message. Please, if interested, return it by e.mail or by ordinary mail to Enrico Vitale. ACCOMODATION: we have reserved a small number of rooms at the hotel "Maison des gens de mer", quai du Risban, tel. 28681522 (it is 150 m. away from the University) at the cost of 192 F per night, breakfast included. There are also some little more expensive hotels near the beach. Keeping in mind that June is already a holiday month for some people in France, we suggest to send us the registration form with the reservation (Friday/Saturday/Sunday nights) as soon as possible and not beyond May, 15th. HOW TO REACH DUNKERQUE: BY CAR: motorways: A 1 from Paris A 25 from Lille A 16 from Calais (exit 33) from Brussels and Oostende: A 18 till you get Veurne (Furnes) then follow the direction Dunkerque to A 16 (exit 33) BY TRAIN: TGV from Paris-Nord on Friday at 18:22 (arrival 19:55) TGV from Lille-Europe on Friday at 19:22 (arrival 19:55) TGV from Paris-Nord on Saturday at 7:22 (arrival 9:23) from Brussels-Midi at 17:22 (arrival at Lille-Europe 18:37) Let us recall that for the TGV the formula Joker 30 (Joker 8) is very interesting, but you have to book at least 30 (resp. 8) days before departure. BY BOAT: there is a ferry Ramsgate-Dunkerque (Sally Ferry) at 16:00, arrival 19:30, but with no easy connection to the city for those without a car. HOW TO REACH THE UNIVERSITY: the University building is located in the centre of Dunkerque. It is easily recognizable with its metallic wing-shaped roof and is commonly known as "la Citadelle". It is a 10-minute walk from the railway station (take rue du Chemin de Fer, then rue des Fusilliers Marins and cross the water at the bridge Pont de Perthuis) or from the Beffroy of the Cathedral (straight on leaving the Beffroy on your right-hand and then croos the water at the bridge Pont de Perthuis). If you are interested, we will send you a map of Dunkerque by fax. Please, circulate this announcement among your colleagues. Dominique Bourn Enrico Vitale +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Registration Form: please, return it to Enrico Vitale by e.mail or by ordinary mail. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ - I intend to come to the 61st meeting of the PSSL - I should like to give a talk entitled lasting about minutes - Please reserve accomodation for Friday/Saturday/Sunday night(s) Name: Address: e.mail: ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Dominique BOURN Enrico VITALE Laboratoire LANGAL - Faculte de Sciences - Universite du Littoral 1 quai Freycinet - B.P. 5526 - 59379 Dunkerque - FRANCE tel. 0033-28237161--0033-28237173 - fax. 0033-28237039 - Vitale, e.mail: vitale@lma.univ-littoral.fr Date: Mon, 1 Apr 1996 14:29:42 -0400 (AST) Subject: help Date: Mon, 1 Apr 1996 08:36:57 From: karanda@macs.nul.ls I am interested in quasigroups and loops, and their applicatins. If you know any e-mail address of a group of people working in these areas, please send it to me so that I can contact them. -- hussein mansuri karanda Date: Wed, 3 Apr 1996 16:33:40 -0400 (AST) Subject: Subtypes Date: Wed, 3 Apr 1996 12:22:45 EST5EDT
From Prof. Lambek:
Thomas Streicher raises the question how to deal with subtypes. As was shown in the book ``Introduction to higher order categorical logic'', every type theory $L$ has a conservative extension, namely the internal language of the topos generated by $L$, in which the sets of $L$ become types, hence subsets become subtypes. Jim Lambek lambek@triples.math.mcgill.ca Date: Wed, 3 Apr 1996 16:31:36 -0400 (AST) Subject: another request of help Date: Tue, 2 Apr 1996 16:45:03 +0200 (MET DST) From: bovetti@di.unito.it <bovetti@educ.di.unito.it> Dear categorists, for my thesis I am interested in ccpo, effective F-spaces and recursion theory on some particular domain like cpo and "effective sets ". If you know any e-mail address of a group of people working in these areas, please send it to me so that I can contact them; in particular I'm also interested in some different formulation of recursive ( effective ) operator ( different e.g. from Rogers ). Some address of paper available on FTP over these subjects are also needed. If you can help me e-mail at this recipient or at my e-mail bovetti@educ.di.unito.it THANKS YOU ALL. -- Date: Thu, 4 Apr 1996 14:15:01 -0400 (AST) Subject: Re: Subtypes Date: Thu, 04 Apr 1996 20:08:28 MESZ From: Thomas Streicher <streicher@mathematik.th-darmstadt.de> I definitely appreciate the following answer to my mail by Jim Lambek though I am afraid I wanted to make emphasise another aspect
Thomas Streicher raises the question how to deal with subtypes. As was shown in the book ``Introduction to higher order categorical logic'', every type theory $L$ has a conservative extension, namely the internal language of the topos generated by $L$, in which the sets of $L$ become types, hence subsets become subtypes.
I have been aware of this (standard) construction that can be found in most textbooks on topos theory. One does not only have to extend the language by the subset types but ALSO by constants for a lot of new morphism (where the domain or the codomain is a new type). The problem is not a mathematical one but a question of notational economy : if I know that a \in {a : A | P(a)} and P(a) for a predicate P on A then I am not allowed to conclude a \in A but only iota_{A,P}(a) provided I use the extension of the language formally. For a precise formulation of the syntax of a language with subtypes see e.g. top of page 134 W. Phoa An Introduction to Fibrations, Topos Theory, the Effective ToposW. Phoa An Introduction to Fibrations, Topos Theory, the Effective Topos and Modest Sets (Univ. Edinburgh LFCS Report, obtainable by ftp from the Imperial College server) As I have said in my mail it is possible to give a syntax for subtypes BUT when really working in the formal system it gets horribly clumsy to carry around all the inclusions all the time. Formalised set theory avoids this (but surely has other defects I know). As long as one does not really work inside a formal system but only reasons about a a formal system one never will notice these defects I guess. Thomas Streicher Date: Tue, 9 Apr 1996 08:53:49 -0300 (ADT) Subject: Re:subtypes etc. Date: Mon, 08 Apr 1996 22:50:05 -0500 (EST) From: F. W. Lawvere <mthfwl@ubvms.cc.buffalo.edu> A contrast has been pointed out : working in a formal system "vs" reasoning about a formal system. Using both should lead in spiral fashion to both better formal systems and more knowledge about that which they describe. In this spirit we should surely expose the defects of a formal system rather than conceal them. The formal system may need to be changed. It would be one- sided to only "work in " a system, accepting it as a divine condemnation that we have to endure. The objective necessity that every map has both a domain and a codomain is one of the great principles of category theory. Already in the 30s it was known to be required by even the simplest functors such as pi-zero. Hence the answer to both of the questions Does topos logic correspond to type theory ? "or" Does topos logic correspond to set theory ? is NO. Both were earlier, partially successful attempts to make explicit some "necessary laws of the development of thinking in all the areas of mathematics". All areas of mathematics lead to qualitative leaps like the functors of algebraic topology. For mathematics, freedom came from the recognition of that necessity : the foundational role was thus abandoned in practice by st which promoted the "freedom" allegedly deriving from ignoring codomains, while tt, though recognizing some codomains (as types ) , gets entangled in the "flexibility" of refusing to declare variables,i.e. to specify domains. A set in a topos is neither a type nor not a type : there are sets of exactly the right size to be susceptible of being wired up as memory banks which serve as power types or function types (or more specific mathematically-oriented objects ) relative to some given sets, the wiring being suitable maps which serve as evaluations, inclusions, etc. A set in a topos is not a von Neumann "set" either; it has a cohesiveness due to the incidence relations between its elements (right actions, pullbacks) so is a "Menge" not due to an excessive and irrelevant structure but to a structure adapted to the mathematical category of cohesiveness at hand. We carry the inclusions around only as long as we need them. Already Gauss pointed out that when a subset (i.e. an inclusion map) arises, it may be very significant to study the domain in its own intrinsic self, but this is difficult to make precise in st or tt. Of course "subset" is not a binary relation between sets but a given map, a mathematical necessity that needs to be recognized by any truly flexible formalization in a way coherent enough to work in. Given two inclusion maps b, c with the same codomain A, it is clear what is a proof that "b is included in c" as subsets of A, and given any element x of A (i.e. any map with codomain A), a proof that "x belongs to b" is formally the same kind of thing. Hence by composing proofs we can always conclude that x belongs to c, independently of whether these subsets arose by equalizing some maps P with domain A. Of course some improved version of tt is needed to handle the presentation of cccs, but the basic issue of how to deal formally with inclusions and memberships between subsets arising as equalizers arises already with Lex. In general given any left adjoint, such as the one from Cat to Lex or from Cat to CCC or the one from sets to monoids,etc, there is an objective notion of presentation that arises. Formal systems are subjective instruments for describing and clarifying such presentations. It would seem that the idea of Burroni (described in Lambek &Scott) would lead to an effective formal system for presenting Lex over Cat. Naturally such formal systems would involve specifying both domains and codomains. I believe that some of the implementations mentioned by Rydeheard have these features, while others follow the less efficient route of describing categories in some previously -programmed system of logic. In the end it will surely be simpler, leading to greater freedom and fewer complications, to explicitly take the objectively necessary into account, rather than to succumb to a naive belief in the "freedom" to neglect some essential ingredient. There need not be an inevitable mismatch between useable formal systems and the mathematical structures they strive to present. Date: Tue, 9 Apr 1996 20:20:22 -0300 (ADT) Subject: Categories and Education at TSM Date: Mon, 08 Apr 1996 22:51:21 -0500 (EST) From: mthfwl@ubvms.cc.buffalo.edu SPECIAL SESSION AT THE TORONTO SPRING MEETING The organizers of the Toronto Spring Meeting at York University have decided to include a special session at the meeting on mathematical education from the perspective of category theorists, specifically our duty to teach category theory to the younger generation. Experiences and suggestions on teaching category theory to computer science or math students, whether beginning graduates, younger or more advanced undergraduates, and as a course in itself or within a course on calculus or topology or algebra or combinatorics are all encouraged. The session will be moderated by Bill Lawvere. This note is to provide a chance for participants to collect thoughts in the short time before the meeting, and to invite contributions, either before the meeting or later, from other members of the community. Bill Lawvere, Joan Wick Pelletier, Walter Tholen Date: Tue, 9 Apr 1996 20:22:35 -0300 (ADT) Subject: TSM Program Date: Tue, 9 Apr 1996 13:38:24 -0400 (EDT) From: York cat <yorkcat@mathstat.yorku.ca> TORONTO SPRING MEETING on Category Theory - April 13/14, 1996 All lectures will be held in Vari Hall, Room D, on the York University campus at 4700 Keele Street in North York (Metropolitan Toronto). PROGRAM Saturday: 9:00- 9:10 OPENING 9:10- 10:00 Robert Pare: Representables for double categories 10:10- 10:35 David B. Benson: Cartesian closure in categories of Diers categories 10:40- 11:05 Andrew Ensor: Using sketches to represent notions such as natural transformations 11:20- 11:45 Richard Squire: Applications of the Cantor-Bendixon derivative to dualities 11:50- 12:15 Dorette Pronk: Cohomology of orbifolds 12:20- 12:45 Michael Makkai: On James Dolan's definition of weak n-category 12:50- 2:15 LUNCH 2:20- 3:10 Maria Cristina Pedicchio: Recent developments in commutator theory 3:15- 3:40 Aurelio Carboni: Syntactic characterization of various classes of locally presentable categories 3:45- 4:10 Jonathon Funk: The locally connected coreflection of a Grothendieck topos: an application of the theory of locally presentable categories 4:20- 4:45 D. Pumplu"n: Metrics in convex modules 4:50- 5:30 DISCUSSION: The role of category theory in undergraduate education Moderator: F.W. Lawvere Sunday: 9:10- 10:00 Andre' Joyal: Free bicompletion of categories - construction and meaning 10:10- 10:35 Hongde Hu: Distributivity, softness and free bicomplete categories 10:40- 11:05 Joanne Walters-Wayland: Metrically determined subcategories of uniform spaces 11:20- 11:45 Christopher Gilmour: Realcompactifications and Lindelo"fications of frames 11:50- 12:15 Sandro Fusco: Functorial treatment of the Grothendieck construction 12:20- 12:45 Fred E. J. Linton: Connectedness and (Sierpinski space)^2 Financial support from the Academic Iniatives Fund of the Department of Mathematics and Statistics at York University is gratefully acknowledged. Date: Wed, 10 Apr 1996 13:36:35 -0300 (ADT) Subject: Re: Categories and Education at TSM (fwd) Date: Wed, 10 Apr 1996 08:42:59 -0400 (EDT) From: James Stasheff <jds@math.unc.edu> ---------- Forwarded message ---------- Date: Wed, 10 Apr 1996 07:40:02 -0500 From: Ed Dubinsky <bbf@sage.cc.purdue.edu> To: jds@math.unc.edu, mathed@math.sunysb.edu Cc: bbf@sage.cc.purdue.edu Subject: Re: Categories and Education at TSM (fwd) People might be interested to know that towards the end of his life, Piaget was trying to see how categroy theory might be used to help understand children's thinking. I think he was particularly interested in the move from thinking about a category as a class of sets with certain permissible functions between them, to the more axiomatic description in terms of morphisms. He wrote one book and at least one paper on the subject. ed dubinsky Date: Sat, 13 Apr 1996 08:41:33 -0300 (ADT) Subject: Re: Categories and Education at TSM Date: Sat, 13 Apr 1996 11:38:14 +1000 (EST) From: Ronnie BROWN <rbrown@mpce.mq.edu.au> Tim Porter and I wrote an article for the general rerader `The methodology of mathematics' published in Math. Gazette July, 1995, in which we emphasise the question as to what are the objects of study of mathematics, what does it try to find out about these objects, and what are the tools with which these objects are studied. These would seem likely to be basic questions for the beginners in mathematics. The paper can be downloaded from http://www.bangor.ac.uk/~mas010/papers/methmatg.ps Answers could be of the type: Mathematics is the art and science of patterns and structures, and their growth and change. This is why mathematics underlies most of the other sciences, and gives a language for description, deduction and calculation with strange new objects which arise in everyday life, and in science, technology, and social sciences. In order to study structures, you need a mathematics of structures, and in the current age this seems to be category theory, par excellence. The interesting question is how much can people who are used to maths as pluses and minuses actually appreciate of this. It is well worth trying to put it over, because if people do not have some feeling for these basic points, then the subject will be regarded with a mystique, and something not for them. Another advantage of this metalevel discussion is that it enables the possibility of some critique of category theory as practised. I am not trying to make this critique, but suggesting that we need a context in which discussion can take place, to allow an analysis of future directions! The point also is that we need an argument for mathematics (and in particular, for category theory), which can be put to the general public and to government. The current situation is that the applicable parts of maths are tapped off for the development of other subjects, where they can often get notable funding, none of which goes to the source of these ideas. Indeed, they are no longer `mathematics'. How long can this source last, without proper support and nourishment, and an understanding of its achievements? Ronnie Brown Date: Sun, 14 Apr 1996 08:46:32 -0300 (ADT) Subject: Finite Model Theory Tutorial Date: Fri, 12 Apr 96 16:44:41 BST From: Roy L. Crole <rlc3@mcs.le.ac.uk> FINITE MODEL THEORY Problems, Methods and Applications - A Tutorial - Second Announcement. University of Wales Swansea, 7--9 July, 1996. Finite model theory has emerged in recent years as a very active area of research, on the frontier of logic, combinatorics and computer science. The two-day tutorial to be held in Swansea will present an in-depth introduction to the field aimed at postgraduate students and postdoctoral researchers (though open to all). Topics covered will include the central problems and methods of finite model theory, as well as applications in complexity theory, databases and computer aided verification. The detailed programme and a registration form are attached. The cost of registration is 380 GBP. A limited number of subsidised places are available for postgraduate students at 340 GBP. These will be awarded on a first come first served basis, so early registration is recommended. Registration includes: - Accommodation for the nights of Sunday, 7 July and Monday, 8 July. - Reception on Sunday evening. - Breakfast and lunch on Monday and Tuesday, as well as dinner on Monday evening. - Coffee and Tea breaks. - A copy of all course materials. The meeting is supported by a grant from the London Mathematical Society through the MathFit programme. For further information contact: Anuj Dawar Department of Computer Science Univeristy of Wales Swansea Swansea SA2 8PP. e-mail: a.dawar@swansea.ac.uk Tel.: +44 (0)1792 205678 ext.4805 Fax.: +44 (0)1792 295708. --------------------------------------------------------------------------- PROGRAMME Sunday, 7 July 1996 18:00--22:00 Registration and Welcome Reception. Monday, 8 July 1996 8:45 Opening Remarks 9:00 Capturing Complexity Classes. Iain A. Stewart, University of Leicester. 10:30 Coffee break. 11:00 Model Theory on Finite Structures. Anuj Dawar, University of Wales Swansea. 12:30 Lunch break. 14:00 Logical Reductions. Iain A. Stewart 15:30 Tea break. 16:00 Finite Variable Logics. Anuj Dawar 18:30 Dinner followed by informal social. Tuesday, 9 July 1996 9:00 Finite Model Theory and Databases. Stephane Grumbach, INRIA, Rocquencourt. 10:30 Coffee break. 11:00 Logics and Complexity in Finite Model Theory. Ian Hodkinson, Imperial College, London. 12:30 Lunch break. 14:00 Playing Ehrenfeucht Games. Clemens Lautemann, Universitaet Mainz. 15:30 Tea break. 16:00 Model Checking Games and Other Games. Colin Stirling, Edinburgh University. ------------------------------------------------------------------------- Finite Model Theory Tutorial Swansea 7--9 July 1996 Registration Form Name: Affiliation: Address: e-mail: Telephone: Please specify any dietary restrictions: Indicate amount enclosed (tick one): Student 340 GBP [] Other 380 GBP [] Return this registration form with the appropriate payment to: Anuj Dawar Department of Computer Science Univeristy of Wales Swansea Swansea SA2 8PP United Kingdom. e-mail: a.dawar@swansea.ac.uk Tel.: 01792 205678 ext.4805 Fax.: 01792 295708. (Cheques should be made payable to the University of Wales Swansea) Date: Sun, 14 Apr 1996 08:47:35 -0300 (ADT) Subject: Piaget Date: Sat, 13 Apr 1996 15:05:29 +0100 From: Alberto Peruzzi <peruzzi@dada.it> The use made of categories by Piaget was unsatisfactory in many respects, although it is an undoubtful merit to have recognised the relevance of categories in dealing with the architecture of mathematical structures in relationship with the cognitive development. The main defect was that also in 1974 he didn't realise the role of adjoints: the lack of consideration for adjoints prevented him from having a precise model of the growth in structural complexity (as when he tried to explain the passage from a monoid of "operations" to its "completion" into a group). This general remark can be easily substantiated by those who know Piaget's theory of cognitive stages. I argued for it already in a paper going back to 1978, "unfortunately" written in Italian. (I can mail the paper, or some related publications in English, to those who are interested.) Alberto Peruzzi Date: Mon, 15 Apr 1996 09:04:41 -0300 (ADT) Subject: FREYD FEST Date: Sun, 14 Apr 1996 22:45:38 -0400 From: Andre Scedrov <scedrov@saul.cis.upenn.edu> __ __ __ | / \ / | / | | | | _ | | |___ \__/ \__/ | \__ A N D __ __ ___ ___ ___ __ / / \ |\ /| | \ | | | /\ | | / \ |\ | | | | | V | |__/ | | | /__\ | | | | | \| \__ \__/ | | | |__| | / \ | | \__/ | | T H E S E M I N A R *********************************************** S P E C I A L M E E T I N G I N H O N O R O F P E T E R F R E Y D ON THE OCCASION OF HIS SIXTIETH BIRTHDAY *********************************************** Freyday, April 19, 1996, 2:30-6:30 PM University of Pennsylvania DRL A6 ANOTHER LOOK AT THE CHU CONSTRUCTION Michael Barr McGill University 2:30-3:30 PM Abstract. We take another look at the Chu construction and show how to simplify it by looking at it as a module category in a trivial Chu category. This simplifies the construction substantially, especially in the case of a non-symmetric biclosed monoidal category. We also show that if the original category is accessible, then for any of a large class of ``polynomial-like'' functors, the category of coalgebras has cofree objects. PETER FREYD AND THE DINATURAL WORLD Philip J. Scott University of Ottawa 4:15-5:15 PM Abstract. In this talk we discuss the notion of dinaturality and its relationships to fundamental questions in algebra, semantics of programming languages, and logic. Exploring the dinatural "calculus" has been a consistent (even if implicit) theme in many of Freyd's recent works, from coherence theorems in category theory, to work on fixed point recursion, to his most recent theory of "para-categories" and "para-mathematics" . We survey this interesting concept from its inception in algebraic topology to its emergence in semantics of programming languages. We end with various recent connections to proof theory and linear logic. CATEGORIES, ALLEGORIES, AND LOGIC PROGRAMMING James Lipton Wesleyan University 5:30-6:30 PM Abstract. We will discuss allegory-theoretic compilation, fibrational proof theory, and categorical semantics. We will look at how categorical perspectives may be used to give a sufficiently general semantics to encompass many extensions of logic programming, and to give some guidelines on how to design future extensions, and abstract machines. We will discuss some of the problems involved in "liberating declarative programming from a given syntactic definition" and in capturing such notions as uniformily semantically. Date: Wed, 17 Apr 1996 15:07:54 -0300 (ADT) Subject: FMCS-96 Workshop -- first announcement Date: Wed, 17 Apr 1996 02:29:36 -0700 Subject: FMCS-96 Workshop -- first announcement Foundational Methods in Computer Science: A workshop on applications of categories in computer science 1996 June 1-2 to be held on the campus of Washington State University Pullman WA 99164-2752 USA As always, the focus of this workshop is the applications of categories to computer science, and to encourage cooperation on these matters between computer scientists and mathematicians interested in this topic. In previous sessions, some of the talks have been quite categorical while others concentrate upon computer science matters which may excite the interests of category theorists. This workshop annual series strongly encourages the participation of young researchers of every age. As is the tradition in this workshop series, there is a preceeding tutorial day on Friday, 1996 May 31. Here is a list of possible areas, not meant to be in any sense limiting, for those interested in contributing talks: Categorical and functional programming Program specification and verification Duality Concurrency theory Computer programs about categories Pedagogy and foundational issues This workshop is informal, even casual, but certain details need early attention so that the workshop might go smoothly. The cost will be as modest as possible consistent with having an enjoyable and productive workshop. These costs are entirely for the purposes of proper digestion: snacks during session breaks, a reception on Friday night and a workshop dinner on Saturday night. Please respond by return email with your positive intention as soon as may be. If you wish to contribute a talk, please email a tentative title. Looking forward to seeing you at the end of May and the very beginning of June, Best, David (509) 335-2706 dbenson@eecs.wsu.edu ----------------------TRANSPORTATION-------------------------------- Air -- via Spokane (GEG). Airlines include United, Northwest, Horizon, Alaska, Delta, Southwest. Upon arrival, rent a car or else use Link Transporation limo, which you may reserve also through your travel agent: (208) 882 1223 (800) 359 4541 One way: $37. Round trip: $52. Be sure to reserve for your arrival. Link will wait for late airplanes. (For example, the last Link trip will wait for the last UA flight from Chicago O'Hare) Southbound Leaves Spokane International Airport 8:00xs 12:05 2:30x 6:30 9:15x Arrives Pullman 10:00xs 1:50 4:10x 8:10 10:50x Northbound Leaves Pullman (WSU CUB) 5:00xs 8:15 10:15x 2:45 5:45x Arrives Spokane Airport 6:45xs 10:00 12:00x 4:30 7:30x x -- not Saturdays s -- not Sundays Horizon flys directly to Pullman from Seattle (SeaTac) and from Portland and also Boise. Fares from California, via Alaska Airlines, to Portland or Seattle and thence on to Pullman are hardly more than flying just to Portland or Seattle. In the past this has been true of Northwest flights from anywhere into SeaTac, but I forgot to check whether or not this is still valid. [Exactly one-half of the Horizon flights from Seattle fly first into the Lewiston airport, followed by the 10 minute hop to Pullman. Try to book on the other half, which go around the other way. Reverse the half for departure from Pullman.] You may rent a car at the Pullman airport, take a taxi, or if at all possible, we will arrange to meet you at the airport. For those planning to attend MFPS in Boulder, UA 302 departs Spokane at 2:10pm on Sunday, June 2, arriving at 5:18pm at the United concourse of the new DIA -- Denver International Airport. I will be driving up to Spokane in ample time for this flight and will be happy to take 1 or 2 more people up with me. If there are more than I can take, we can instead arrange for a special Link Transportation limo to pick us up at the WSU CUB, near the conference room, to leave us directly in front of the United ticket counters -- for a fee, of course. By car -- If you are driving from Spokane, please let me know if you would like information about scenic routes. This is the best time of year to go car touring in the channeled scablands, changing a 1.6 hour drive to Pullman into a 3.3 hour drive -- but well worth it! If coming from another direction, similar car touring sidetrips can be recommended. In the near vicinity are the unusual Palouse Falls, the Drumheller (Scabland) dry falls, the channeled scablands. A bit further are the Grand Coulee and its dam, as well as other coulees undeservedly less well-known. All of this unusual landscape is the result of the (last) ice age Breitz Floods, about 40 of them each involving a Great Lake's worth of water released within the space of a few days. The 10 to 12 thousand years since the floods has done rather little to erase the remarkable evidence of this catastrophe. To the east are the mountains of Idaho. This year you will be able to access the high country via auto by the end of May. All in all, if you have a bit of extra time, car touring in this vicinity provides unsurpassed sights which are rather little known. -------------RESTING------------------------------------------------- There are motels and a city campground within walking distance of restuarants, downtown, and the conference room. I am attempting to arrange the use of the University's conference dorm for this weekend. The dorm, if available, is quite lovely, and for a more modest price than most of the motels. An announcement regarding accommodations will be sent to registering participants. ------------ENTERTAINMENT-------------------------------------------- Nothing can be more entertaining than Foundational Methods of Computer Science, so we will have a reception on Friday night and a workshop dinner on Saturday night. -----------WHAT TO DO NOW--------------------------------------------- Send me a return email if you are planning to come. Book your airflights early, since the airplanes seem to be running rather full this year. dbenson@eecs.wsu.edu Date: Thu, 18 Apr 1996 08:49:50 -0300 (ADT) Subject: 3rd WoLLIC'96 - Programme Date: Wed, 17 Apr 96 17:30:41 EST From: Ruy de Queiroz <ruy@di.ufpe.br> Re: 3rd Workshop on Logic, Language, Information and Computation (WoLLIC'96) May 8-10 1996 Salvador (Bahia), Brazil Sponsored by FoLLI, ASL, SBC Financial support by CNPq, CAPES, FINEP We are happy to present the programme of the 3rd WoLLIC'96, together with general information and registration form. If you are planning to participate, please fill in the registration form and send it to the e-mail address wollic96@di.ufpe.br (There is no need to send money now.) The Workshop is the third of a series started in 1994, and is held under the auspices of the European Association for Logic, Language and Information (FoLLI) and the Interest Group in Pure and Applied Logics (IGPL). As from the 1996 version, it is an Association for Symbolic Logic (ASL) sponsored meeting. It has also the institutional sponsorship of Sociedade Brasileira de Computacao (SBC). The next installment (4th WoLLIC'97) will most probably be held in Fortaleza (Ceara') from the 30th of July to the 1st of August 1997. (The First Call for Contributions will soon be released.) ******************************************************************************** 3rd Workshop on Logic, Language, Information and Computation (WoLLIC'96) May 8-10, 1996 Salvador (Bahia), Brazil Sponsored by FoLLI, ASL, SBC Financial support by CNPq, CAPES, FINEP ******************************************************************************** *********** May 8, 1996 *********** Morning: Model Theory and Games 08:30-09:30 (Invited talk) Semantic Games of Imperfect Information Wilfrid Hodges School of Mathematical Sci., Queen Mary and Westfield College, UK 09:30-10:30 (Invited talk, XI EBL'96) The Logic of Uncertain Information Daniele Mundici Department of Computer Science, University of Milan, Italy 10:30-10:40 Coffee/Tea break 10:40-11:00 Games and Abstract Machines for Classical Logic H. Herbelin INRIA, France 11:00-11:20 Paraconsistent Model Theory N. C. A. da Costa, J.-Y. Beziau, O. Bueno Department of Philosophy, University of Sao Paulo, Brazil 11:20-11:30 Coffee/Tea break 11:30-12:30 (Invited talk) Some Semantical Aspects of Linear Logic Andreas Blass Mathematics Department, University of Michigan, USA Afternoon: Program Logic 14:00-15:00 (Invited talk) Verifying Timed and Hybrid Systems Amir Pnueli Department of Computer Science, Weizmann Inst. of Science, Israel 15:00-15:10 Coffee/Tea break 15:10-15:30 An Instance of the CLP(X) Scheme which allows to deal with Temporal Reasoning Problems F. Ibanez, R. Forradellas, L. Rueda Universidad Nacional de San Juan, Argentina 15:30-15:50 Operational Semantics of Extended Statecharts (XCHART) F. Lucena, M. Harada, H. Liesenberg Department of Computer Science, State Univ. of Campinas, Brazil 15:50-16:10 Handling Uncertainty and Resources: Petri Nets, Fuzzy and Linear Logic J. Cardoso, R. Valette, B. Pradin-Chezalviel Federal University of Santa Catarina, Brazil and LAAS, Toulouse, France 16:10-16:30 A Machine-assisted Proof of the Subject Reduction Property for a Small Typed Functional Language A. Bove, A. Tasistro Instituto de Computaci\'on, Univ. de la Rep\'ublica, Uruguay, and Chalmers University, Gothenburg, Sweden 16:30-16:40 Coffee/Tea break 16:40-17:40 (Invited talk) Trees, Ordinals and Termination Nachum Dershowitz Dept. Computer Science, Univ. of Illinois at Urbana-Champaign, USA *********** May 9, 1996 *********** Morning: Semantics of Computation 08:30-09:30 (Invited talk) Topological Relational Structures Michael Smyth Department of Computing, Imperial College, UK 09:30-09:40 Coffee/Tea break 09:40-10:00 Denotational Semantics in Synthetic Domain Theory B. Reus Informatik, Ludwig Maximilians Universit\"at, Munich, Germany 10:00-10:20 A Categorical Logic for Information Systems M. Johnson School of Mathematics and Computing, Macquarie Univ., Australia 10:20-10:40 Vernacular Rules for General Recursion M. Henson Department of Computer Science, University of Essex, UK 10:40-11:00 Interface in Linear Logic: A Finite System of Generators D. Bechet CRIN-CNRS & INRIA-Lorraine, France 11:00-11:10 Coffee/Tea break 11:10-12:10 (Invited talk) `Logical' Relations between Syntax and Semantics Andrew Pitts Computer Laboratory, Cambridge University, UK Afternoon: Proof Theory 14:00-15:00 (Invited talk) Proof Theory and Semantics for Structurally-Free Logics J. Michael Dunn Depts of Computer Science and Philosophy, Indiana University, USA 15:00-15:10 Coffee/Tea break 15:10-15:30 Labelled Resolution for Classical and Non-Classical Logics D. Gabbay, U. Reyle Department of Computing, Imperial College, UK and Inst. f. Maschinelle Sprachverarbeitung, Stuttgart Univ., Germany 15:30-15:50 LDS - Natural Deduction for Substructural Logics K. Broda, M. Finger, A. Russo Department of Computing, Imperial College, UK Inst. of Mathematics and Statistics, Univ. of Sao Paulo, Brazil 15:50-16:10 Automated Deduction and Labelling: Case Studies in Categorial Logics S. Luz Filho Center for Cognitive Sciences, Edinburgh University, UK 16:10-16:30 Relational Proof Theory for FL, Linear and other Substructural Logics W. MacCaull Dept of Maths & Computing Sciences, St.Francis Xavier Univ., Canada 16:30-16:40 Coffee/Tea break 16:40-17:00 Universal Quantifiers in Logic Programs A. Bowers, P. M. Hill, F. Ibanez Department of Computer Science, University of Bristol, UK, School of Computer Studies, University of Leeds, UK, and Universidad Nacional de San Juan, Argentina 17:00-17:20 Decision Procedures and Model Building in Equational Clause Logic C. G. Ferm{\"u}ller, A. Leitsch CSLI, Stanford University, USA, and Technische Universit\"at Wien, Austria 17:20-17:40 Prolog and Automatic Language Implementation Systems M. Mernik, V. Zumer Fac. of Electrical Eng. & Computer Sci., Univ. of Maribor, Slovenia 17:40-18:00 Belief Revision View of Logic Programming J. C. P. da Silva, S. R. M. Veloso COPPE/Sistemas, Federal University of Rio de Janeiro, Brazil ************ May 10, 1996 ************ Morning: Knowledge Representation and Discourse Representation 08:30-09:30 (Invited talk) Three Levels of Knowledge Representation Peter G\"ardenfors Cognitive Science, Lund University, Sweden 09:30-09:40 Coffee/Tea break 09:40-10:00 Explanation Inference F. Pirri Dip. di Informatica e Sistemistica, Univ. Roma La Sapienza, Italy 10:00-10:20 On Dynamics of Full and Restricted First-Order Theories: Expressivity versus Tractability O. J. Lemon Department of Computer Science, University of Manchester, UK 10:20-10:40 Some Characteristics of the Inconsistent Default Logic Reasoning Style A. T. de C. Martins, T. H. C. Pequeno Department of Computer Science, Federal Univ. of Ceara', Brazil 10:40-11:00 A Logic for Careful Nonmonotonic Reasoning A. Buchsbaum, T. H. C. Pequeno Department of Computer Science, Federal Univ. of Ceara', Brazil 11:00-11:10 Coffee/Tea break 11:10-12:10 (Invited talk) Update Semantics meets Discourse Jeroen Groenendijk Inst. Logic, Lang. & Computation, Univ. Amsterdam, The Netherlands Afternoon: Algebraic Logic 14:00-15:00 (Invited talk) Sequential Algebra Roger Maddux Department of Mathematics, Iowa State University, USA 15:00-15:10 Coffee/Tea break 15:10-15:30 Fork Algebraic Datatypes P. E. Mart\'{\i}nez Lopez, G. A. Baum Depto. de Inform\'atica, Univ. Nacional de La Plata, Argentina 15:30-15:50 A Computational Meta Logic for the Horn Fragment of LF C. Sch\"urmann Department of Computer Science, Carnegie-Mellon University, USA 15:50-16:10 Implementing Martin-L\"of's Theory of Types in a Higher-Order Logic Programming Language G. Calder\'on Instituto de Computaci\'on, Universidad de la Rep\'ublica, Uruguay 16:10-16:30 Additive Linear Logic with Analytic Cut J.-Y. Marion Universit\'e Nancy 2 & CRIN-CNRS, France 16:30-16:40 Coffee/Tea break 16:40-17:00 Parsing Natural Language using LDS: A Prototype M. Finger, R. Kibble, R. Kempson Inst. of Mathematics and Statistics, Univ. of Sao Paulo, Brazil and Dept. Linguistics, School of Oriental and African Studies, UK 17:00-17:20 An Extended Lambek Calculus Approach to Spanish Possessives D. Wonsever Instituto de Computaci\'on, Universidad de la Rep\'ublica, Uruguay 17:20-17:40 Second Document Ranking Using a Keyfact Concept M.-S. Jun, S.-Y. Park System Software Dept., Electronics and Telecomm. Res. Inst., Korea 17:40-18:00 A Logic with Strong Negation and Variable Domains for Situation Theory X. Wang, P. Mott School of Computer Studies, University of Leeds, UK 18:00-18:10 Coffee/Tea break 18:10-19:10 (Invited talk, XI EBL'96) The Interaction between Logic and Specification Theory Paulo Veloso Department of Informatics, Pontificial Catholic Univ., Rio, Brazil 19:10 CLOSING ----------------- GETTING TO SALVADOR (BAHIA). There are various regular flights from Europe and USA to Salvador's `4 de Julho International Airport'. The airport is located at some 30Km from the city (out of inner city boundaries), and is under one hour by car to center of town. Besides the Brazilian airlines VARIG and VASP, one European airline has at least two direct flights to Salvador per week: TAP Air Portugal, from Lisbon. If you get to Brazil via Rio, you will able to choose from various domestic flights, some direct, from Rio to Salvador. (This is not exactly high season, but beginning of May is likely to be a fairly difficult time of the year to find seats in domestic flights, so please be safe by booking in advance.) There are five main domestic airlines in Brazil: VARIG, RIO-SUL, VASP, TRANSBRASIL and TAM. APPROXIMATE COST OF A TAXI RIDE FROM THE AIRPORT TO "SOL VITORIA MARINA HOTEL": R$45.00 (forty five reals). DIAL-A-CAB COMPANIES. Chame taxi - (+55 71) 241-2266 Radio taxi - (+55 71) 243-4333 Teletaxi - (+55 71) 321-9988 Ligue taxi - (+55 71) 358-0733 CURRENCY. Brazil's currency called `Real' (pronounce it (almost) like in French), abbrev. `R$', and R$1.00 is worth approx. US$1.00 (to be more precise, US$1=R$0.99 today). Banknotes: R$1, R$5, R$10, R$50, R$100. Coins: R$1, R$0.50, R$0.25, R$0.10, R$0.05, R$0.01. GENERAL TOURIST INFORMATION ABOUT SALVADOR AND BAHIA. Please take a look at the web pages: http://www.got.net/~rgosula/bahia.html and http://www.ufba.br/~promocpd/versao2/promo3.html (general business info) Or contact the travel agent: Visao Turismo Rua dos Algibebes 96 Comercio 40015-060 Salvador, Bahia BRAZIL Tel. (+55 71) 241-6877 Fax (+55 71) 242-0928 Quote `3rd WoLLIC96/SEMINFO/UFBA' to get special prices. THE LOCATION. Salvador, Capital of the Bahia state, the first European settlement of Portuguese America and the first Capital of Brazil, is where all the most important colonial buildings were constructed: churches, convents, palaces, forts and many other monuments. Part of the city historical center has been safekept by UNESCO since 1985. Five hundred years of blending Native American, Portuguese, and African influences have left a rich culture to its people, which can be felt on its music, food, and mysticism. Salvador is located on the northeastern coast of Brazil and the sun shines year round with the average temperature of 25 degrees Celsius. It is surrounded by palm trees and beaches with warm water. City population is around 2.5 million and life style is quite relaxed. It is generally agreed that Salvador is Brazil's tourism industry best asset after Rio. With the recent restauration of its historic center, a visit to Salvador is a rather unique experience, not just for its natural beauty but also because it is quite simply THE place to see the best of Afro-Brazilian culture. THE WEATHER. Beginning of May in Salvador is usually fresh and rather windy (i.e. breezy, since it is by the sea), with temperatures around 22-24 degrees Celsius. Being the end of the rainy season an occasional shower may still fall during the first weeks of May. Usually, though, it is dry and a prelude to pleasant June. THE VENUE. The 3rd WoLLIC'96 is part of a larger event being held in the "Ondina" Campus of the Federal University of Bahia (UFBA). The lectures will be at the Main Library ("Biblioteca Central") at the Ondina Campus. Full address: Pavilhao de Aulas da Federacao (PAF) Instituto de Matematica / Centro de Processamento de Dados (CPD) Universidade Federal da Bahia (UFBA) Av. Adhemar de Barros, s/n Ondina Salvador, BA 40170-110 Brazil Tel.: +55 71 245 0899 Fax: +55 71 247 9907 E-mail: wollic96@di.ufpe.br http://www.di.ufpe.br/simposios/wollic http://www.ufba.br//seminfo96 During the workshop, transportation will be available Hotel-University-Hotel leaving every day from the `Sol Vitoria Marina Hotel' at 8:00 in the morning. It will leave the Campus in the afternoon at around 6:00pm, to take the participants back to the Hotel. RECEPTION DESK. There will be a reception desk in the Entrance Hall of the Main Library. The campus will be signposted with posters of `3rd WoLLIC 96' (in purple and yellow colours). WELCOME EVENING. There will be a social gathering in the evening of Wednesday 8th May, 8pm, near the main entrance to the "PAF". (To be confirmed) PUBLICATION OF THE PAPERS. Remember that the authors of contributions will be invited to submit full papers for publication (after the usual refereeing procedures) in a Special Issue of the `Journal of the Interest Group in Pure and Applied Logics'(ISSN 0945-9103). (A draft copy of the Special Issue with the papers selected from WoLLIC'95 will be available during this year's event.) -------------------------------------------------------------------------------- ACOMMODATION ------------ MAIN HOTEL Sol Victoria Marina Hotel (Apart hotel 4 stars) Price: Double room - R$50,00 + 5% Tax (Valid between the 6th and the 10th of May 1996) For Reservations Contact: Veronica Mestanza Dept. of Events - tel +55 71 336-7736 (voice & facsimile) (Extension 3329) Address: Av. Sete de Setembro, 2068 Vitoria 40.080-001 Salvador, Bahia BRAZIL MORE ECONOMICAL ALTERNATIVES: Ondina Plaza Hotel (3 stars) Price : Double room - R$36,00 (Valid between the 6th and the 10th of May 1996) Location : Ondina (close to the campus of UFBA) Tel. +55 71 245-8188 Pousada Por do Sol e Pousada dos Orixas (Block booking made for: 6th to 10th May 1996) Lodging with 04 beds per room, price includes beddings. Price: with breakfast: R$15,00 per person without breakfast: R$13,00 per person Meals: R$13,00 For Reservations Contact: Ms. Jovelina Address: Ladeira dos Aflitos, 45 Centro Salvador, Bahia BRAZIL Tel.: +55 71 321-6257 YOUTH HOSTELS The hostels below do NOT require YHA membership for GROUPS OF MORE THAN 10. Prices for group booking may be negotiated. 1. Albergue da Juventude Price: R$12,00 with breakfast Location: Pituba (not too far from the campus of UFBA) Tel: +55 71 248-0527 Vacancies: 50 2. Albergue da Juventude do Pelo Price: R$12,00 with breakfast Location: Pelourinho (Old part of Salvador) Tel: +55 71 242-8061 Vacancies: 60 3. Albergue das Laranjeiras (Well recommended) Price: R$11,50 with breakfast Location: Pelourinho (Old part of Salvador) Tel.: +55 71 321-1366 Vacancies: 57 4. Albergue do Passo Pousada e Turismo Tel +55 71 326-1951 5. Albergue da Juventude Dois de Julho Tel +55 71 243-9513 NB.: Further information and reservations must be made directly with the hotels/hostels via the telephone numbers given above. The quotes given are based on "promotional prices" especially arranged for the events, and are valid until the 15th of April. -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 3rd WoLLIC'96 3rd Workshop on Logic, Language, Information and Computation 1996 Salvador (Bahia), May 8-10 1996 Sponsored by FoLLI, ASL, SBC REGISTRATION FORM Name: Affiliation: Postal Address: Tel.: Fax: E-mail: Arrival date: Departure date: Category: [ ] Regular R$110.00 [ ] Member of IGPL R$66.00 (*) [ ] Student R$33.00 (please specify name and e-mail address of supervisor) Title of the paper to be presented (if appropriate): (*) If you wish to join the `Interest Group in Pure and Applied Logics' (the clearing house of The European Association of Logic, Language and Information - FoLLI) send a submission request to R.deQueiroz@doc.ic.ac.uk with full name, postal address, e-mail, tel, fax, and research interests. PLEASE DO NOT SEND MONEY NOW. Pay here at the reception desk. Fill in the form and send it to: ***** wollic96@di.ufpe.br ***** -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- ****************** FOR SPEAKERS ONLY: ****************** PUBLICATION OF THE PAPERS. Remember that the authors of contributions will be invited to submit full papers for publication (after the usual refereeing procedures) in a Special Issue of the `Journal of the Interest Group in Pure and Applied Logics' (ISSN 0945-9103). (A draft copy of the Special Issue with the papers selected from the 2nd WoLLIC'95 will be available during this year's event.) Looking forward to welcoming you in Salvador, With much appreciation for your interest and attention, Best regards, Ruy de Queiroz --- ._, Ruy J. G. B. de Queiroz ,_| |._/\ Departamento de Informatica | |o/^^~-._ Universidade Federal de Pernambuco (UFPE) em Recife /-' | ~ Av. Prof. Luis Freire, s/n \__/|_ /' Cidade Universitaria \__ | . Recife, PE 50740-540 | __/' BRASIL > /' tel. +55 81 271 8430 /' /' fax: +55 81 271 8438 ~~^\/' e-mail: ruy@di.ufpe.br Date: Fri, 19 Apr 1996 14:21:16 -0300 (ADT) Subject: My talk at Penn Date: Fri, 19 Apr 1996 11:41:28 -0400 From: Michael Barr <barr@triples.math.mcgill.ca> A number of people have written to ask if the paper I am talking about at Penn is available. Yes. In the ftp directory of triples, in pub/barr/newasymm.dvi and .ps. Michael Date: Mon, 22 Apr 1996 08:49:56 -0300 (ADT) Subject: FLoC'96 Advance Program Date: Sun, 21 Apr 96 08:11 EDT From: Doug Howe <howe@research.att.com> Call for Participation 1996 FEDERATED LOGIC CONFERENCE FLoC'96 July 27 - August 3, 1996, Rutgers University, New Jersey, USA FLoC is modelled after the Federated Computer Research Conference (FCRC), and brings together synergetic conferences that explore connections between logic and computer science. The following conferences will be part of FLoC. CADE: 13th International Conference on July 30 - August 3 Automated Deduction CAV: 8th International Conference on July 31 - August 3 Computer-Aided Verification LICS: 11th Annual IEEE Symposium on July 27 - July 30 Logic in Computer Science RTA: 7th International Conference on July 27 - July 30 Rewriting Techniques and Applications DIMACS, an NSF Science and Technology Center located at Rutgers University, will host FLoC as part of its Special Year on Logic and Algorithms and has provided significant support for reduced student fees. FLoC is also supported by generous contributions from AT&T Laboratories, Bell Labs-Lucent Technologies, DIMACS, IBM Almaden Research, IEEE Computer Society and the Max-Planck Institute. +------------------------------------------------+ | | | *ADVANCE PROGRAM AND REGISTRATION INFORMATION* | | | | http://www.research.att.com/lics/floc/ | | ftp://ftp.research.att.com/dist/floc/ | | | +------------------------------------------------+ FURTHER INFORMATION: For e-mail enquiries regarding the participating meetings, use cade13@cisr.anu.edu.au, cav96@research.att.com, lics96@cs.cmu.edu or rta96@mpi-sb.mpg.de. For other enquiries about FLoC, write to lics-request@research.att.com. PROGRAM/CONFERENCE CHAIRS: Michael McRobbie and John Slaney (CADE); Rajeev Alur and Thomas A. Henzinger (CAV); Edmund M. Clarke (LICS); Harald Ganzinger (RTA). LOCAL ARRANGEMENTS: Amy Felty (CADE), Rajeev Alur (CAV), Jon G. Riecke (LICS, FLoC committee chair), Leo Bachmair (RTA). FLOC STEERING COMMITTEE: Stephen Mahaney, Moshe Vardi (chair). FLOC PUBLICITY CHAIR: Douglas J. Howe. Tel: +1 (908) 582-3837. Fax: +1 (908) 582-7550. Date: Tue, 23 Apr 1996 08:20:18 -0300 (ADT) Subject: Prof. Nobuo Yoneda passed away Date: Tue, 23 Apr 96 12:18:58 JST From: KINOSHITA Yoshiki <yoshiki@etl.go.jp> Prof. Nobuo Yoneda passed away at 12:21 on Sunday, 21 April, due to heart failure. He was attacked by acute pancreatitis in January and had been in bed since then. The funeral will take place at his house at 12:00 on Wednesday, 24 April, in Shintoist style. Very little is known about Prof. Yoneda in Euro-America-Australian community. So, I will try to write what I heard from Yoneda; there might be some inaccuracy since I am relying on my memory. Also, I work in computer science and do not understand much of mathmatics. I would very much appreciate any corrections or supplements. Prof. Yoneda was born on 28 March, 1930. He studied mathematics in the University of Tokyo; in the last year of his studies he followed the seminar of Prof. Shokiti Iyanaga, where he became interested in algebraic topology. Soon after that (or maybe when he was still an undergraduate), Prof. Samuel Eilenberg visited Japan, and Yoneda traveled around Japan with him, as a translator and guide. At that time, he was exposed to the Cartan-Eilenberg book, which was still in galley form. Later, he got a Fulbright scholarship and he visited Princeton, to study with Eilenberg. Those days, the Yen was still very weak, so even the Fulbright money was not enough to support even a modest living in U.S. Therefore, he worked as a proofreader at a European publisher (Elsevier? NorthHolland? maybe American), to earn money for the study in U.S. Even 25 years later, he seemed to be proud of his professional skill as a proofreader, which he gained then. When he arrived in Princeton, Eilenberg had moved (sabbatical?) to France (or maybe, Eilenberg left US just after Yoneda's arrival). So, Yoneda went to France a year later. At that time, Saunders Mac Lane was visiting category theorists, apparently to obtain information to write his book (or former survey), and he met the young Yoneda, among others. The interview started in a Caf\'{e} at Gare du Nord, and went on and on, and was continued even in Yoneda's train until its departure. The contents of this talk was later named by Mac Lane as Yoneda lemma. So, the famous Yoneda lemma was born in Gare du Nord. This must have been a good memory for Yoneda; I heard him tell this story many times. I do not know whether Mac Lane managed to leave the train before departure! Yoneda's trip to America/Europe continued for two years. When he came back to Japan, his thesis advisor, Iyanaga, suggested him to begin studying computers, which he did. Some computer scientists know Yoneda as a member of Algol68 committee. Until 1976, Yoneda was a professor of the department of mathematics at Gakushu-in University in Tokyo, and he took a professorship in 1977 at the newly established department of information science at the University of Tokyo, where he had 15 MSc. students (in Japan, MSc students are research students, at least before 1990) and at least 5 DSc. (Doctor of Science, equivalent to Euro-American PhD) students, three of which are DSc course students. He retired from the University of Tokyo in 1990, at the age of 60, as is custom there, and moved to Tokyo Denki University, where he worked as a professor until this March. I do not know the phrase in English for this situation, so permit me to write in Japanese: tutusinde Yoneda sensei no gomeihuku wo oinori mousiagemasu. Yoshiki Kinoshita -- Electrotechnical Laboratory 1-1-4, Umezono, Tsukuba-shi, Ibaraki, 305 Japan phone: 0298-58-5859 FAX: 0298-58-5891 e-mail: yoshiki@etl.go.jp Date: Wed, 24 Apr 1996 09:39:02 -0300 (ADT) Subject: Symmetric Monoidal Closed Categories Date: Wed, 24 Apr 1996 09:20:57 +0100 From: Chris Francis Townsend <cft@doc.ic.ac.uk> I am just about to finish the writing up of my thesis and have one remaining difficulty. I needed to use the following result about a symmetric monoidal closed categorie C, `If C has coequalizers then so does the category CMon(C) of commutative monoids over C' I feel sure that this result is well known by anybody who has worked with symmetric monoidal closed categories and so have been frustrated by the fact that can't find a reference for it. Does anybody know where I can find such a reference for this result (or of some generalization of it)? Thanks Chris Townsend Date: Wed, 24 Apr 1996 15:19:57 -0300 (ADT) Subject: Re: Symmetric Monoidal Closed Categories Date: Wed, 24 Apr 96 17:17 BST From: Dr. P.T. Johnstone <P.T.Johnstone@pmms.cam.ac.uk> In my "Topos Theory" book, you will *very nearly* find a proof that, if C is symmetric monoidal closed, then the forgetful functor CMon(C) --> C creates coequalizers of reflexive pairs. (See Lemma 0.17 and Exercise 0.1; in the latter, the cartesian products have to be replaced by tensor products, but that is a triviality.) Given that all finite colimits can be constructed from coproducts and reflexive coequalizers (and that CMon(C) always has finite coproducts, for a different reason), that is all you need. Peter Johnstone Date: Thu, 25 Apr 1996 14:23:49 -0300 (ADT) Subject: Graduate Algebra text Date: Wed, 24 Apr 1996 12:13:46 -0400 From: Charles Wells <cfw2@po.cwru.edu> Is there any graduate algebra text still in print that uses the language of categories? Mac Lane and Birkhoff, and Hungerford, both seem to be out of print. (I deduced this from Macmillan's and Springer's webservers rather than Books In Print). Charles Wells, Department of Mathematics, Case Western Reserve University 10900 Euclid Avenue, Cleveland, OH 44016-7058. Office phone: 216 368 2893. Math dept phone: 216 368 2880. Fax: 216 368 5163. Home phone: 216 774 1926. Home Page URL: http://www.cwru.edu/CWRU/Dept/Artsci/math/wells/home.html. "Some have said that I cannot sing; but no one will say that I didn't sing." --Florence Foster Jenkins Date: Fri, 26 Apr 1996 08:49:17 -0300 (ADT) Subject: Algebra Date: Thu, 25 Apr 1996 17:05:00 -0400 From: Walter Tholen <tholen@mathstat.yorku.ca> Subject: Algebra Concerning Charles Wells' question, there is the following more recent graduate text in Algebra which, at a fairly early stage, contains a reasonable chapter on categories (including adjoint functors), but which does not necessarily stress categorical methods and language lateron: "Algebra" by Mark Steinberger, PWS Publishing Company, Boston 1994. -- Walter Tholen tel: (1-416) 736 5250 Dept. of Mathematics and Statistics or 736 2100 ext. 33918 York University fax: (1-416) 736 5757 North York, Ontario email: tholen@mathstat.yorku.ca Canada M3J 1P3 web: http://www.math.yorku.ca/Who/Faculty/Tholen/menu.html Date: Fri, 26 Apr 1996 08:48:25 -0300 (ADT) Subject: Re: Graduate Algebra text Date: Thu, 25 Apr 1996 12:40:07 -0700 From: David Espinosa <espinosa@kestrel.edu> Date: Thu, 25 Apr 1996 14:23:26 -0300 (ADT) Date: Wed, 24 Apr 1996 12:13:46 -0400 From: Charles Wells <cfw2@po.cwru.edu> Is there any graduate algebra text still in print that uses the language of categories? Mac Lane and Birkhoff, and Hungerford, both seem to be out of print. (I deduced this from Macmillan's and Springer's webservers rather than Books In Print). You can get MacLane and Birkhoff's graduate algebra book from Chelsea Publishing (212) 889-8095 for only about $40. It's excellent! David Date: Fri, 26 Apr 1996 13:43:29 -0300 (ADT) Subject: Re: Graduate Algebra text Date: Fri, 26 Apr 1996 09:59:57 -0400 (EDT) From: James Stasheff <jds@math.unc.edu> Jim Stasheff jds@math.unc.edu Math-UNC (919)-962-9607 Chapel Hill NC FAX:(919)-962-2568 27599-3250 May 15 - August 15: 146 Woodland Dr Lansdale PA 19446 (215)822-6707 ---------- Forwarded message ---------- Date: Fri, 26 Apr 1996 09:55:30 +0500 From: Ivan Cherednik <chered@linus.math.unc.edu> To: jds@math.unc.edu Subject: Re: Graduate Algebra text (fwd) Lang's algebra is a good intro. Actually, Grothendick's "On some questions of homological algebra" is the best. -Ivan Date: Mon, 29 Apr 1996 10:56:12 -0300 (ADT) Subject: SAS'96: last call for papers Date: Sat, 27 Apr 1996 16:35:46 +0200 (MET DST) From: Radhia Cousot <radhia@lix.polytechnique.fr> Third Call For Papers International Static Analysis Symposium (SAS'96) Aachen, Germany, 24-26 September 1996 Static Analysis is increasingly recognised as a fundamental tool for high performance implementations and verification systems of high-level programming languages. The last two decades have witnessed substantial developments in this area, ranging from theoretical frameworks to design, implementation, and application of analysers in optimising compilers. The Third International Static Analysis Symposium, SAS'96, will be held in Aachen in combination with the Fifth International Conference on Algebraic and Logic Programming (ALP'96) and the Eighth International Symposium on Programming Languages, Implementations, Logics, and Programs (PLILP'96). The technical program for SAS'96 will consist of invited lectures, presentations of refereed papers, and software demonstrations. Contributions are welcome on all aspects of Static Analysis, including, but not limited to Abstract Interpretation Optimising Compilers Complexity Theoretical Frameworks Experimental Evaluation Verification Systems Specific Analyses Type Inference Partial Evaluation Abstract Domains Submissions can address any programming paradigm, including concurrent, constraint, functional, imperative, logic and object-oriented programming. Survey papers that present some aspect of the above topics with a new coherence are also welcome. Papers must be written in English, must not exceed 15 pages (excluding references and figures), and must contain a cover page containing the following: a 200-word abstract, keywords, postal and electronic mailing addresses, and phone numbers and fax numbers of one of the authors. Submissions should arrive at the address below by 6 MAY 1996 in one of these two forms: by email, a Postscript file; or by post, six paper copies. Electronic submission is preferred, but do ensure that your submission is self-contained and prints on A4 paper. At the time of submission a message containing an ASCII or LaTeX version of the paper's cover page should be sent by email. Authors will be notified of the acceptance or rejection of their papers by 25 JUNE 1996. Final versions of the accepted papers must be received in camera-ready form by 17 JULY 1996. We anticipate that the proceedings will be published by Springer-Verlag in the LNCS series. Contact and Submission Address: Program Co-Chairs: Email: rcousot@lix.polytechnique.fr Radhia Cousot (FR) Phone: +33 1 69 33 45 95 Dave Schmidt (US) Fax: +33 1 69 33 30 14 Post: Radhia Cousot Program Committee: LIX Franncois Bourdoncle(FR) Ecole Polytechnique Alain Deutsch (FR) 91128 Palaiseau cedex Roberto Giacobazzi (IT) France Nicolas Halbwachs (FR) Chris Hankin (UK) Local Organisation: William L. Harrison (US) Markus Mohnen Neil Jones (DK) RWTH Aachen, Lehrstuhl fur Informatik II Peter Lee (US) D-52056 Aachen, Germany Kim Marriott (AU) aachen96@informatik.rwth-aachen.de Jens Palsberg (US/DK) Hanne Riis Nielson (DK) Important Dates: Deadline: 6 May Carolyn Talcott (US) Notification: 25 June Mads Tofte (DK) Final Version: 17 July Reinhard Wilhelm (DE) Information on SAS'96 (and ALP'96 and PLILP'96) is available from the WWW URL http://www-i2.informatik.rwth-aachen.de/aachen96/ Date: Mon, 29 Apr 1996 10:57:29 -0300 (ADT) Subject: AMS special session Date: Sat, 27 Apr 1996 13:49:44 -0400 (EDT) From: James Stasheff <jds@math.unc.edu> Art Dupre and I are hosting a speical session at the AMS meeting in October at Rider many aspects of algebraic topology and homotopical algebra and category theory are suitabvle the deadline seems to be upon us for abstracts so if you are at all intersted please let us know and submit a formal abstract the actual talk can differ somewhat if developments warrant Jim Stasheff jds@math.unc.edu Math-UNC (919)-962-9607 Chapel Hill NC FAX:(919)-962-2568 27599-3250 May 15 - August 15: 146 Woodland Dr Lansdale PA 19446 (215)822-6707 Date: Mon, 29 Apr 1996 10:58:55 -0300 (ADT) Subject: LICS'96 Advance Program + Registration Information Date: Sun, 28 Apr 96 10:59 EDT From: Doug Howe <howe@research.att.com> [This announcement is a plain-text summary of the LICS-related parts of the FLoC'96 advance program. The full program is available on the web at http://www.research.att.com/lics/floc/, and via anonymous ftp from ftp.research.att.com, directory /dist/floc.] Call for Participation 11TH ANNUAL IEEE SYMPOSIUM ON LOGIC IN COMPUTER SCIENCE July 27-30, 1996 Rutgers University, New Jersey, USA Hosted by DIMACS Sponsored by IEEE COMPUTER SOCIETY with support from AT&T Laboratories Lucent Technologies Bell Laboratories IBM Almaden Research Center The LICS Symposium aims to attract original papers of high quality on theoretical and practical topics in computer science that relate to logic in a broad sense, including algebraic, categorical and topological approaches. The symposium draws papers from a wide range of areas: abstract data types, automated deduction, categorical models, concurrency, constraint programming, constructive mathematics, database theory, domain theory, finite model theory, hybrid systems, logics of knowledge, lambda and combinatory calculi, linear logic, logical aspects of computational complexity, logics in artificial intelligence, logic programming, modal and temporal logics, model checking, program logic and semantics, rewriting, logical aspects of symbolic computing, software specification, type systems, and verification. Program Chair: E. Clarke (CMU) Program Committee: S. Buss (UC San Diego), A. Emerson (UT Austin), S. German (IBM Watson), G. Gottlob (TU Vienna), O. Grumberg (Technion), D. Howe (Bell Labs), C. Kirchner (INRIA & CRIN), K. Kunen (Wisconsin), P. Lincoln (SRI), J. Mitchell (Stanford), U. Montanari (Univ. Pisa), P. Panangaden (McGill), F. Pfenning (CMU), J. Rushby (SRI), C. Stirling (Edinburgh), A. Stolboushkin (UCLA), G. Winskel (Aarhus). Conference Chair: J.G. Riecke (Bell Labs). Publicity: A. Felty (Bell Labs), D. Howe (Bell Labs). General Chair: M.Y. Vardi (Rice University) Organizing Committee: M. Abadi, S. Abramsky, S. Artemov, E. Boerger, A. Borodin, W. Brauer, A. Bundy, S. Buss, E. Clarke, R. Constable, A. Felty, U. Goltz, D. Howe, G. Huet, J.-P. Jouannaud, D. Kapur, C. Kirchner, P. Kolaitis, D. Kozen, T. Leighton, D. Leivant, A.R. Meyer, D. Miller, J. Mitchell, Y. Moschovakis, M. Okada, P. Panangaden, J. Remmel, J. Riecke, S. Ronchi della Rocca, A. Scedrov, D. Scott, J. Tiuryn, M.Y. Vardi. Email: lics96@cs.cmu.edu WWW: http://www.research.att.com/lics/ +---------------------------------------------------------+ | DEADLINES | | | | Early Registration 21 Jun 1996 | | On-Campus Housing Reservation 21 Jun 1996 | | Hotel Reservation 28 Jun 1996 | +---------------------------------------------------------+ TRAVEL ADVISORY =============== The 1996 Summer Olympics will take place in Atlanta from 19 July to 3 August, 1996. Travel to the East Coast will be especially heavy during these times. It is strongly recommended that you make airline reservations as early as possible. CONFERENCE PROGRAM ================== Friday, 26 July 1996 -------------------- RECEPTION: 17:30-19:30. Saturday, 27 July 1996 ---------------------- WELCOME: 9:00-9:15. FINITE MODEL THEORY I: 9:15-10:30. Chair: K. Kunen. A Generalization of Fagin's Theorem J. Antonio Medina & Neil Immerman (University of Massachusetts) DATALOG SIRUPs Uniform Boundedness Is Undecidable Jerzy Marcinkowski (University of Wroclaw) On the Structure of Queries in Constraint Query Languages Michael Benedikt & Leonid Libkin (Bell Labs) COFFEE BREAK: 10:30-11:00. CONCURRENCY: 11:00-12:40. Chair: U. Montanari. A Fully Abstract Domain Model for the Pi-Calculus Ian Stark (University of Aarhus) A Fully-Abstract Model for the Pi-Calculus M.P. Fiore (University of Edinburgh), E. Moggi (Universita di Genova) & D. Sangiorgi (INRIA) Higher Dimensional Transition Systems Gian Luca Cattani & Vladimiro Sassone (University of Aarhus) An Algebraic Theory of Process Efficiency V. Natarajan & Rance Cleaveland (North Carolina State University) LUNCH BREAK: 12:40-14:15. TYPES I: 14:15-15:30. Chair: J. Mitchell. The Subtyping Problem for Second-Order Types is Undecidable Jerzy Tiuryn & Pawel Urzyczyn (Warsaw University) Subtyping Dependent Types David Aspinall (University of Edinburgh) & Adriana Compagnoni (University of Cambridge) Reduction-Free Normalisation for a Polymorphic System Thorsten Altenkirch (University of Edinburgh), Martin Hofmann & Thomas Streicher (TH Darmstadt) COFFEE BREAK: 15:30-16:00. TEMPORAL LOGIC AND MU-CALCULUS: 16:00-17:40. Chair: E.A. Emerson. An Until Hierarchy for Temporal Logic Kousha Etessami & Thomas Wilke (DIMACS) Locally Linear Time Temporal Logic R. Ramanujam (Universitat Kiel) A Modal Mu-Calculus for Durational Transition Systems Helmut Seidl (Universitat Trier) Tarskian Set Constraints David McAllester (AT&T Laboratories), Robert Givan (MIT AI Laboratory), Dexter Kozen (Cornell University) & Carl Witty (MIT AI Laboratory) Sunday, 28 July 1996 -------------------- PLENARY SESSION WITH RTA: 9:15-10:30. Chair: E. Clarke. Design of a Proof Assistant Gerard Huet (INRIA Rocquencourt) COFFEE BREAK: 10:30-11:00. REASONING ABOUT PROGRAMS: 11:00-12:40. Chair: P. Lincoln. Reasoning about Local Variables with Operationally-Based Logical Relations Andrew M. Pitts (Cambridge University) The Essence of Parallel Algol Stephen Brookes (Carnegie Mellon University) Games and Full Abstraction for FPC Guy McCusker (Imperial College) A Temporal Logic Approach to Binding Time Analysis Rowan Davies (Carnegie Mellon University) LUNCH BREAK: 12:40-14:15. MODEL CHECKING I: 14:15-15:30. Chair: S. German. Symbolic Protocol Verification with Queue BDDs Patrice Godefroid & David E. Long (Bell Labs) Reactive Modules Rajeev Alur (Bell Labs) & Thomas A. Henzinger (University of California at Berkeley) Model-checking of Correctness Conditions for Concurrent Objects Rajeev Alur (Bell Labs), Ken McMillan (Cadence Berkeley Labs) & Doron Peled (Bell Labs) COFFEE BREAK: 15:30-16:00. TYPES II: 16:00-17:40. Chair: D. Howe. A Semantic View of Classical Proofs: Type-Theoretic, Categorical, and Denotational Characterizations C.-H. L. Ong (University of Oxford & National University of Singapore) Syntactic Considerations on Recursive Types Martmn Abadi (Systems Research Center, Digital Equipment Corporation) & Marcelo P. Fiore (University of Edinburgh) On the Expressive Power of Simply Typed and Let-Polymorphic Lambda Calculi Gerd G. Hillebrand (University of Pennsylvania) & Paris C. Kanellakis (Brown University) A Linear Logical Framework Iliano Cervesato & Frank Pfenning (Carnegie Mellon University) BUSINESS MEETING: 20:00-21:30. Monday, 29 July 1996 -------------------- TUTORIAL: 9:15-10:30. Chair: J. Rushby. The Theory of Hybrid Automata Thomas A. Henzinger (University of California at Berkeley) Abstract: Hybrid automata, which combine discrete transition graphs with continuous dynamical systems, are mathematical models for digital systems that interact with analog environments. Hybrid automata can be viewed as infinite-state transition systems, and this view gives insights into the structure of hybrid state spaces. For example, for certain interesting classes of hybrid automata, language equivalence, mutual similarity, or bisimilarity induce finite quotients of infinite state spaces. These results can be exploited by analysis techniques for finite-state systems. COFFEE BREAK: 10:30-11:00. MODEL CHECKING II: 11:00-12:40. Chair: O. Grumberg. Partial-Order Methods for Model Checking: From Linear Time to Branching Time Bernard Willems & Pierre Wolper (Universite de Liege) Efficient Model Checking via the Equational Mu-Calculus Girish Bhat & Rance Cleaveland (North Carolina State University) General Decidability Theorems for Infinite-State Systems Parosh Aziz Abdulla (Uppsala University), Karlis Cerans (University of Latvia), Bengt Jonsson (Uppsala University) & Yih-Kuen Tsay (National Taiwan University) Relating Word and Tree Automata Orna Kupferman (Bell Labs), Shmuel Safra (Tel Aviv University) & Moshe Y. Vardi (Rice University) LUNCH BREAK: 12:40-14:15. FINITE MODEL THEORY II: 14:15-15:30. Chair: G. Gottlob. More about Recursive Structures: Descriptive Complexity and Zero-One Laws Tirza Hirst & David Harel (The Weizmann Institute of Science) On the Expressive Power of Variable-Confined Logics Phokion G. Kolaitis (University of California, Santa Cruz) & Moshe Y. Vardi (Rice University) Zero-One Laws for Gilbert Random Graphs Gregory L. McColm (University of South Florida) COFFEE BREAK: 15:30-16:00. SEMANTICS AND DOMAINS: 16:00-17:40. Chair: G. Winskel. When Scott is Weak on the Top Abbas Edalat (Imperial College) Integration in Real PCF Abbas Edalat & Martmn Hvtzel Escards (Imperial College) Game Semantics and Abstract Machines Vincent Danos (Paris 7 & CNRS) Hugo Herbelin (Paris 7 & INRIA) & Laurent Regnier (LMD-CNRS Marseille) Semantics of Normal Logic Programs and Contested Information Shekhar Pradhan (University of Maryland, College Park & Central Missouri State University) JOINT BANQUET WITH RTA: 19:00-22:00. Chair: C.A. Gunter. Dinner speech by Dana Scott on ``Some Reflections on Logic and Logicians''. Tuesday, 30 July 1996 --------------------- TUTORIAL: 9:15-10:30. Chair: P. Panangaden. Lattices, Categories and Communication Andre Joyal (Universite du Quebec a Montreal) Abstract: We describe a theory of communication based on free lattices and free bicomplete categories. It is based on a game-theoretic representation of bicomplete categories. All our results extend to enriched categories. In (*) we associate a two player game to each term representing an element of a free lattice. To a pair of terms we associate a three player game, a mediator facing two opposites. A strategy for the mediator is viewed as a communication strategy between the opposites. A communication strategy is complete iff it is winning. The mediator has a complete communication strategy iff the corresponding terms can be compared in the free lattice. Here we show that the objects and arrows of free bicomplete categories have a similar game-theoretic interpretation. Two communication strategies are operationally equivalent iff they define the same arrow in the free bicomplete category. Many connectives of linear logic have an interpretation in free bicomplete categories. Our work suggests similarities between the world of computing and that of financing. Reference: (*) "Free lattices, communication and money games". In Proceedings of the 10th International Congress of Logic, Methodology and Philosophy of Science. Firenze, August 1995. COFFEE BREAK: 10:30-11:00. LAMBDA CALCULUS: 11:00-12:40. Chair: F. Pfenning. Linear Logic, Monads and the Lambda Calculus Nick Benton (University of Cambridge) & Philip Wadler (University of Glasgow) On Order-Incompleteness and Finite Lambda Models Peter Selinger (University of Pennsylvania) Confluence and Preservation of Strong Normalisation in an Explicit Substitutions Calculus Cesar Munoz (INRIA) Completing Partial Combinatory Algebras with Unique Head-Normal Forms Inge Bethke (CWI & University of Utrecht), Jan Willem Klop (CWI & Vrije Universiteit) & Roel de Vrijer (Vrije Universiteit) LUNCH BREAK: 12:40-14:15. REWRITING AND UNIFICATION: 14:15-15:30. Chair: C. Kirchner. Complexity Analysis Based on Ordered Resolution David Basin & Harald Ganzinger (Max-Planck-Institut f|r Informatik) Solving Linear Equations over Semirings Paliath Narendran (State University of New York at Albany) Basic Paramodulation and Decidable Theories Robert Nieuwenhuis (Technical University of Catalonia) COFFEE BREAK: 15:30-16:00. COMPLEXITY AND DECIDABILITY: 16:00-17:40. Chair: A. Stolboushkin. Counting Modulo Quantifiers on Finite Linearly Ordered Trees Juha Nurmonen (University of Helsinki) Simultaneous Rigid E-Unification and Related Algorithmic Problems; Skolemization and Decidability Problems for Fragments of Intuitionistic Logic Anatoli Degtyarev (Uppsala University), Yuri Matiyasevich (Steklov Institute of Mathematics) & Andrei Voronkov (Uppsala University) On the Complexity of Abduction Victor W. Marek (University of Kentucky), Anil Nerode (Cornell University) & Jeffrey B. Remmel (University of California, San Diego) Decision Problems for Semi-Thue Systems with a Few Rules Yuri Matiyasevich (Steklov Institute of Mathematics) & Geraud Senizergueswww (LaBRI, Universite de Bordeaux) FLOC PLENARY SESSION: 20:00-21:30. Chair: M.Y. Vardi. Calculi for Interactions R. Milner (Cambridge University, United Kingdom) LOCATION ======== The conferences will be held at the College Avenue Campus of Rutgers University in downtown New Brunswick, which is easily accessible by air, train, and car. For air travel, New Brunswick is 35 minutes from Newark International Airport, a major U.S. and international airline hub. By rail, the New Brunswick train station is located less than eight blocks from the conference site and is on Amtrak's Northeast corridor. For travel by car, the conference site is approximately three miles from Exit 9 of the New Jersey Turnpike. A postscript map of the College Avenue Campus is available on the web and at the FLoC ftp site (addresses at the beginning of this announcement). Conference check-in and on-site registration will take place at the Main Lounge entrance on the second floor of the Rutgers Student Center (#78 on map, follow signs for exact location). Evening registration is possible the day before the beginning of FLoC, Friday, 26 July from 16:00-19:00. On regular conference days, the registration desk will be open from 8:00-18:00; on Monday, 29 July and Tuesday, 30 July, registration hours will be extended to 19:00. Conference sessions will take place in the Rutgers Student Center and Brower Commons(#57 on map). CADE workshops will take place in Scott Hall(#21 on map). Climate ------- New Jersey in July and August is typically hot, with average daily highs around 85 degrees F (29 degrees C), and overnight lows around 70 degrees F (21 degrees C). Most days are sunny, but also come prepared for the possibility of occasional rain. Things to do ------------ The newly opened Liberty Science Center is a fun, hands-on science museum located in Liberty State Park, about 30-45 minutes from New Brunswick (201-200-1000). From Liberty State Park, one can also take a ferry to the Statue of Liberty and the Immigration Museum at Ellis Island. New York City can be reached in under an hour by rail on New Jersey Transit. Trains run about twice an hour during the week, and once an hour on weekends and at night. Fare is $7.75 one-way, $11.50 round trip excursion. The New Jersey shore is less than an hour from New Brunswick. Points along the shore vary greatly in character. Some, such as Point Pleasant, have long boardwalks with amusement park rides, video arcades, etc. Others, such as Spring Lake, are quiet and uncommercialized with clean and very pretty beaches. Further south, about two hours from New Brunswick, are the casinos of Atlantic City. You can walk for miles and miles along the towpath of the peaceful Delaware and Raritan Canal which runs from New Brunswick south past Princeton. Your registration packet will include a pass for access to the College Avenue Gymnasium (near the dormitories,#77 on map). SOCIAL EVENTS ============= A reception will be held Friday, 26 July, 17:30-19:30. A joint banquet for LICS and RTA participants will be held on Monday, 29 July at 19:00 at the Farrington Manor, a banquet site near New Brunswick. Dana Scott will be giving a talk after dinner. The cost of the banquet is $50 per person. TRAVEL ====== Travel advisory: The 1996 Summer Olympics will take place in Atlanta from 19 July to 3 August, 1996. Travel to the East Coast will be especially heavy during these times. It is strongly recommended that you make airline reservations as early as possible. By air: Newark International Airport is by far the most convenient. A taxi from the airport to New Brunswick costs about $40 (plus nominal tolls) for up to four passengers. This is the flat-rate fare for a licensed taxi from the official-looking taxi stand; it is strongly recommended that you refuse rides offered by unlicensed taxi drivers who may approach you elsewhere in the airport. If renting a car, follow signs out of the airport to New Jersey Turnpike South, and continue with the directions below. By public transportation, take the Airlink bus ($4 exact fare, operates every 20 minutes) to Newark Penn Station and follow the "by rail" directions below. New Jersey Transit train fare is $5.25 one-way or $8 round trip excursion; trains run about twice an hour during the week, and less often in the evening and on weekends. For those arriving at JFK International Airport, there is a shuttle bus operated by Princeton Airporter (phone 800-468-6696). The shuttle stops at Newark Airport (fare $19; follow the above directions) and the East Brunswick Hilton (fare $29; approximately a $7 cab ride to the conference site). The shuttle leaves JFK at 9:00, 11:00, 13:00, 14:00, 15:00, 16:00, 17:00, 18:00, 19:00, 20:00, 21:00, 22:00. Advance reservations are not possible. For information and reservation contact the ground tranportation center on the baggage level. A taxi from JFK to New Brunswick costs approximately $120 for up to four passengers. Driving from JFK to New Brunswick may take up to two hours, and is not recommended if you are not familiar with the area. By car: Take the New Jersey Turnpike (south from Newark or New York, north from Philadelphia) to Exit 9. Follow signs onto Route 18 North or West (labeled differently at different spots) toward New Brunswick. Take the Route 27, Princeton exit onto Albany Street (Route 27) into downtown New Brunswick. The Hyatt Regency Hotel will be on your left after the first light. If staying at the Hyatt, turn left at the next light, Neilson Street, and left again into the front entrance of the hotel. If staying in the dorms, continue past this light to the following light, George Street, and turn right. Stay on George Street to just before the fifth street and turn left into the Parking Deck(#55 on map). If staying in the dorms, go directly to the appropriate dormitory. It is a short walk to Hardenbergh (#49 on map) or Stonier (#56 on map). Parking passes will be provided to all conference registrants who need one. By rail: Take either an Amtrak or a New Jersey Transit train to the New Brunswick train station. This is located at the corner of Albany Street and Easton Avenue. If staying at the Hyatt Regency Hotel, it is a three block walk to the left on Albany Street to the hotel. If staying in the dorms, go directly to the appropriate dormitory. It is about a six block walk to Hardenbergh (#49 on map) or Stonier (#56 on map). There is also a taxi stand in front of the train station on Albany Street. ACCOMMODATIONS ============== We have established the group rate of $89/night for one single, double, triple, or quadruple room at the Hyatt Regency Hotel (about eight blocks from the conference site). This rate is only guaranteed through 28 June 1996, and, due to limited availability, it is strongly recommended that you make reservations as soon as possible. We have reserved dormitory space in two dorms, both of which are an easy walk to the main conference site. Dorm reservations must be made by the early registration deadline of 21 June 1996. Both dorms include daily maid service (linens provided first day for the week and daily fresh towels and beds made), and are fully air-conditioned. The Stonier Hall dorms (#56 on map (uncompressed)) have suites with one shared bedroom and one shared bathroom. Only a block away, the Hardenbergh Hall dorms (#49) have single rooms with baths shared on each floor. If you elect Stonier Hall and do not specify a roommate, a roommate of the same sex may be assigned to your suite. Please specify your dorm preference on your registration form; we will assign space accordingly on a first come, first served basis as long as rooms are available. Unfortunately, because there are only a finite number of rooms within each dormitory, we can neither guarantee your choice of dormitory nor your preference of dates. Note that the accomodations include breakfasts and some dinners (on those nights that do not have banquets). Sorry, but we cannot give rates on rooms without meals, or on rooms on different dates other than those listed below. Reservations ------------ For details on prices and reserving, see the registration/accommodation forms. These are available in postscript on the web and via ftp. FORMS ===== ------------------------------------------------------------------------ INSTRUCTIONS FOR REGISTRATION ------------------------------------------------------------------------ Please include the Conference Fee Form, On-Campus Housing Form (if on-campus housing is desired), and this form with payment and mail to FLoC c/o Priscilla Rasmussen P. O. Box 6148 Somerset, NJ 08875 USA All inquiries should be directed to Priscilla Rasmussen Phone: (908) 873-0672 or (908) 873-3898 Fax: (908) 873-0014 Email: rasmusse@cs.rutgers.edu Please type or print. Name ___________________________________Sex (please circle): Male Female Affiliation ____________________________________________________________ Street Address _________________________________________________________ City, State, Postal Code _______________________________________________ Country ________________________________________________________________ Phone(s) _______________________________________________________________ Fax ____________________________________________________________________ E-mail _________________________________________________________________ Total Due (Registration and Dormitories): ______________________________ Dietary Restrictions (circle if applicable): Vegetarian Kosher Payment: Please enclose a money order, personal check, or bank check, drawn in U.S. dollars, for the full amount payable to "Federated Logic Conference 1996" or "FLoC 1996." All personal checks must be drawn on a U.S. bank. Discount for Students: A reduced registration fee is available for students attending the conferences. If you apply for the student fee, please attach a copy of your student identification for the ongoing year or a letter signed by the head of your department confirming that you are a student. Discount for Members: LICS and CADE offer reduced registration fees for members of certain organizations. CADE offers the possibility of becoming eligible for the reduced fee by joining the Association of Automated Reasoning and enclosing the $7.00 membership fee with your registration. (See next page.) Member rate justification for LICS (if applicable) _____________________ Member rate justification for CADE (if applicable) _____________________ ------------------------------------------------------------------------ CONFERENCE FEES ------------------------------------------------------------------------ All fees are in U.S. currency. Please include this form with your payment. You must be registered for a conference or workshop for each day you attend. For instance, if you register for LICS and want to stay to attend CADE and/or CAV sessions, you must register for CADE or CAV. ------------------------------------------------------------------------ Group 1: LICS or RTA (Circle at most one fee) LICS Registration ----------------- Before June 21 After June 21 *Member $295.00 $380.00 Regular $375.00 $475.00 Student $100.00 $150.00 RTA Registration ---------------- Before June 21 After June 21 Regular $275.00 $375.00 Student $100.00 $150.00 *Includes members of ACM, ASL, EATCS, and IEEE, members of the organizing and program committee, and authors of accepted papers. ------------------------------------------------------------------------ Group 2: LICS/RTA Banquet ($50.00 per person) Number of people:____________ Total Cost:____________ ------------------------------------------------------------------------ Group 3: CADE Workshops (circle the appropriate workshops) (before June 21, $50.00 per workshop; after June 21, $80.00 per workshop) WP-1 WP-2 WP-3 WP-4 WP-5 WP-6 WP-7 Total Cost:____________ ------------------------------------------------------------------------ Group 4: CADE or CAV (Circle at most one fee) CADE Registration ----------------- Before June 21 After June 21 *Member $300.00 $400.00 Regular $330.00 $430.00 Student $100.00 $200.00 CAV Registration ---------------- Before June 21 After June 21 Regular $300.00 $375.00 Student $100.00 $150.00 *Includes current and new members of AAR. ------------------------------------------------------------------------ Group 5: New AAR Membership for CADE member rate (Circle if applicable) $7.00 ------------------------------------------------------------------------ Group 6: CADE/CAV Banquet ($57.00 per person): Number of people:____________ Total Cost:____________ ------------------------------------------------------------------------ Group 7: CADE Excursion (Choose one and indicate number of people): ($50 for Metropolitan Museum & broadway show, $25 all others) Statue of Liberty/Ellis Island:______ Liberty Science Center:______ Metropolitan Museum:______ Metropolitan Museum & broadway show:______ Total Cost:_______ ------------------------------------------------------------------------ ------------------------------------------------------------------------ ON-CAMPUS HOUSING FORM ------------------------------------------------------------------------ We have reserved dormitory space in two dorms, both of which are an easy walk to the main conference site. Dorm reservations must be made by the early registration deadline of 21 June 1996. Both dorms include daily maid service (linens provided first day for the week and daily fresh towels and beds made), and are fully air-conditioned. The Stonier Hall dorms (#56 on map) have suites with one shared bedroom and one shared bathroom. Only a block away, the Hardenbergh Hall dorms (#49) have single rooms with baths shared on each floor. If you elect Stonier Hall and do not specify a roommate, a roommate of the same sex may be assigned to your suite. Please specify your dorm preference on your registration form; we will assign space accordingly on a first come, first served basis as long as rooms are available. Unfortunately, because there are only a finite number of rooms within each dormitory, we can neither guarantee your choice of dormitory nor your preference of dates. Check-in will take place at each dormitory. Check-in hours will be 14:00-22:00 on 26 July and 16:00-22:00 on 29-30 July. Note that the accomodations include breakfasts and some dinners (on those nights that do not have banquets). Sorry, but we cannot give rates on rooms without meals, or on rooms on different dates other than those listed below. All fees are in U.S. Currency. Please circle the applicable fee. Payment due with registration. Please include this form with your payment. First night Checking out Total nights Meals included Fee July 26 July 30 4 4 breakfasts, $160 3 dinners July 26 July 31 5 5 breakfasts, $200 4 dinners July 29 August 3 5 5 breakfasts, $200 3 dinners July 30 August 3 4 4 breakfasts, $160 2 dinners July 26 August 3 8 8 breakfasts, $320 5 dinners Preferred Dormitory (circle one): Stonier Hardenbergh Preferred Roommate (if Stonier Hall is preferred): _____________________ Actual Arrival Date ____________________________________________________ Actual Departure Date __________________________________________________ ------------------------------------------------------------------------ HOTEL INFORMATION ------------------------------------------------------------------------ We have established the group rate of $89/night for one single, double, triple, or quadruple room at the Hyatt Regency Hotel (about eight blocks from the conference site). This rate is only guaranteed through 28 June 1996, and, due to limited availability, it is strongly recommended that you make reservations as soon as possible. To reserve a room, please contact the Hyatt directly at Hyatt Regency Hotel 2 Albany Street New Brunswick, NJ 08901 USA Phone: (908) 873-1234 or (800) 233-1234 Fax: (908) 873-1382 Reservations must be guaranteed by either a check, money order, or credit card. Please be sure to reference FLoC 1996. Parking is available at the hotel for a discounted $2/night. Date: Tue, 30 Apr 1996 15:44:19 -0300 (ADT) Subject: question Date: Tue, 30 Apr 1996 19:07:19 +0000 From: Luis Soares Barbosa <lsb@di.uminho.pt> This is probably a trivial question, but I would appreciate any pointer to a solution: Let A be a denumerable set and A* be the set of finite sequences of A. It is easy to show (by defining two injections) that the set (A* x A*) is isomorphic (as a set) to (A x 2)* -- where 2 is a two element set and x the Cartesian product. The question is how to exhibit the isomorphism (actually the 2 obvious injections are not mutually inverse). Thanks. L. S. Barbosa Date: Tue, 30 Apr 1996 22:40:58 -0300 (ADT) Subject: Re: question Date: Tue, 30 Apr 1996 23:25:52 +0200 (MET DST) From: koslowj@iti.cs.tu-bs.de Concerning Luis Soares Barbosa's question about the isomorphism in set of A^* x A^* and (A x 2)^* for countable A: Just because two sets are countable doesn't mean there has to exist a *canonical* isomorphism. The only canonical function in this setting is induced by the monoid structure: A x 2 in set is (canonically!) isomorphic to A + A (where + means coproduct, i.e., disjoint union in set). The free monoid functor (-)^* is left adjoint and hence preserves coproducts, i.e., (A + A)^* =~ A^* + A^* in mon, the category of monoids (where the coproduct is *not* given by disjoint union). Now the two projections from A^* x A^* to A^* in mon have left inverses (pairing with the empty sequence), hence the universal property of the coproduct induces a canonical monoid-homomorphism from A^* + A^* to A^* x A^*. Incidentally, the two "injections" from A^* to A^* + A^* both have right inverses in mon, hence the universal property of the product induces a canonical monoid-homomorphism from A^* + A^* to A^* x A^*, which coincides with the first one! Although defined by "general abstract nonsense", this homomorphism is easily understood: it decomposes sequences of red and blue elements of A into the red and the blue subsequence. Clearly, this is not injective. We might say that "morally", A^* + A^* is larger than A^* x A^*. That for countable A the underlying sets have the same size is just an accident. Best regards, -- J"urgen -- J\"urgen Koslowski % ITI % This space intentionally left blank. TU Braunschweig % koslowj@iti.cs.tu-bs.de %