January 2009 - Categories - categories.org.au

adjunction of symmetric monoidal closed categories
by Bockermann Bockermann 28 Jan '09

28 Jan '09

Dear mathematicians, I wonder if the following is true. Has anybody a reference, if this is the case? Let V and W be two complete and cocomplete symmetric monoidal closed categories and L: V <--> W :R an adjunction of (lax) symmetric monoidal functors. Let D be a small V- category. Is it true that there is a V-isomorphism V-Fun(D,RW) = R(W-Fun(LD,W)) ? (If not, is this at least the case if L is strict symmetric monoidal?) Thank you for any help. Tony

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bicategory of fractions and homotopy category
by David Roberts 28 Jan '09

28 Jan '09

Hi all, has anyone come across this situation? I have a 2-category where the underlying category has a model structure, and the class of equivalences (from the 2-cat structure) is contained in the weak equivalences. The class of weak equivalences admits a bicategory of fractions, and so one can consider that bicategory as the homotopy 'category' in some sense. Cheers, David Roberts

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Model Theory and Category Theory
by Jonathan CHICHE 齐正航 28 Jan '09

28 Jan '09

Hello, I am looking for references regarding the interplay between Model Theory and Category Theory. I came across an announcement related to this topic recently, possibly on this list, but I cannot find it anymore. There has been a thread about it on the n-Category café a few months ago also. Do you have any other reference? What would be the best place to start? Thanks in advance, Jonathan

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request for comments: "A survey of graphical languages for monoidal categories"
by selinger＠mathstat.dal.ca 27 Jan '09

27 Jan '09

Dear Category Theorists, as you know, there is a proliferation of monoidal categories with additional structure, many of which have graphical languages. For example: autonomous, balanced, braided, compact closed, pivotal, ribbon, rigid, sovereign, spherical, tortile, traced. I have recently written a survey article on all of these graphical languages (and more). The goal was not to re-prove known theorems, but simply to collect most known facts in one location, with references to the primary literature. I have also tried to put a systematic perspective on things. Consequently, I included many results and conjectures that don't seem to appear in the literature at all, or for which only special cases seem to be known. Since this paper will not be refereed in the usual sense (it is supposed to appear as a book chapter), I am instead inviting comments and corrections from all interested parties. I am particularly interested in missing references for any of the results or conjectures, and of course any other corrections you might have. The article is available from: http://www.mathstat.dal.ca/~selinger/papers.html#graphical I hope this will be useful. Thanks! -- Peter ---------------------------------------------------------------------- P. Selinger: A survey of graphical languages for monoidal categories December 2008. 59 pages. Abstract: This article is intended as a reference guide to various notions of monoidal categories and their associated string diagrams. It is hoped that this will be useful not just to mathematicians, but also to physicists, computer scientists, and others who use diagrammatic reasoning. We have opted for a somewhat informal treatment of topological notions, and have omitted most proofs. Nevertheless, the exposition is sufficiently detailed to make it clear what is presently known, and to serve as a starting place for more in-depth study. Where possible, we provide pointers to more rigorous treatments in the literature. Where we include results that have only been proved in special cases, we indicate this in the form of caveats.

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Lie groups and Lie algebras
by Tim Porter 27 Jan '09

27 Jan '09

d" Content-Disposition: inline Content-Transfer-Encoding: 7bit Sender: categories(a)mta.ca Precedence: bulk Reply-To: Tim Porter <t.porter(a)bangor.ac.uk> In the relationship between Lie groups and Lie algebras, there is the neat result that the Lie functor L : LieGrp->LieAlg restricts to an equivalence on the simply connected Lie groups, and that the fibre over any given Lie algebra is the category of those G which are isomorphic to quotients of the one simply connected one of them and hence there is a Galois theory interpretation in terms of central extensions. I am sure that this sort of situation must be much more general than just this case, and is somehow linked to abstract Galois theories. I am hoping that someone can point out really neat categorical results on this (in the literature). I am sure I ought to know them but ... It does not seem to be in Borceux-Janelidze, and my own library on this area is very sadly thin on the ground. Thanks in advance, Tim --=20 Gall y neges e-bost hon, ac unrhyw atodiadau a anfonwyd gyda hi, gynnwys deunydd cyfrinachol ac wedi eu bwriadu i'w defnyddio'n unig gan y sawl y cawsant eu cyfeirio ato (atynt). Os ydych wedi derbyn y neges e-bost hon trwy gamgymeriad, rhowch wybod i'r anfonwr ar unwaith a dil=EBwch y neges. Os na fwriadwyd anfon y neges atoch chi, rhaid i chi beidio =E2 defnyddio, cadw neu ddatgelu unrhyw wybodaeth a gynhwysir ynddi. Mae unrhyw farn neu safbwynt yn eiddo i'r sawl a'i hanfonodd yn unig ac nid yw o anghenraid yn cynrychioli barn Prifysgol Bangor. Nid yw Prifysgol Bangor yn gwarantu bod y neges e-bost hon neu unrhyw atodiadau yn rhydd rhag firysau neu 100% yn ddiogel. Oni bai fod hyn wedi ei ddatgan yn uniongyrchol yn nhestun yr e-bost, nid bwriad y neges e-bost hon yw ffurfio contract rhwymol - mae rhestr o lofnodwyr awdurdodedig ar gael o Swyddfa Cyllid Prifysgol Bangor. www.bangor.ac.uk This email and any attachments may contain confidential material and is solely for the use of the intended recipient(s). If you have received this email in error, please notify the sender immediately and delete this email. If you are not the intended recipient(s), you must not use, retain or disclose any information contained in this email. Any views or opinions are solely those of the sender and do not necessarily represent those of the Bangor University. Bangor University does not guarantee that this email or any attachments are free from viruses or 100% secure. Unless expressly stated in the body of the text of the email, this email is not intended to form a binding contract - a list of authorised signatories is available from the Bangor University Finance Office. www.bangor.ac.uk

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CFP - RelMiCS 11 / AKA 6
by Michael Winter 25 Jan '09

25 Jan '09

Announcement and Call for Papers for the ======================================== 11th International Conference on Relational Methods in Computer Science (RelMiCS 11) ====================================== 6th International Conference on Applications of Kleene Algebra (AKA 6) ============================================================== November 1 to 5, 2009 Doha, Qatar ================================= 1) Conference Over the past fifteen years, the RelMiCS meetings have been a main forum for researchers who use the calculus of relations and similar algebraic formalisms as methodological and conceptual tools. The workshop series on Applications of Kleene algebra started with a Dagstuhl seminar in 2001 and has been co- organised with the RelMiCS conference since. Due to their considerable overlap, the two events have a joint PC and joint proceedings.Their scope comprises relation algebra, fixpoint calculi, semiring theory, iteration algebras, process algebras and dynamic algebras. Applications include formal algebraic modelling, the semantics, analysis and development of programs, formal language theory and combinatorial optimisation. We invite submissions on the general topics of Relation Algebra and Kleene Algebra in computer science. Special focus will lie on formal methods for software engineering, logics of programs and links with neighbouring disciplines. Particular topics of the conference cover, but are not limited to the theory of - relation algebras and Kleene algebras - related formalisms such as process algebras, fixed point calculi, idempotent semirings, quantales, allegories, dynamic algebras, cylindric algebras and their applications in areas such as - verification, analysis and development of programs and algorithms - relational formal methods such as B or Z, tabular methods, - algebraic approaches to logics of programs, modal and dynamic logics, interval and temporal logics - algebraic semantics of programming languages - graph theory and combinatorial optimisation - games, automata and language theory - mechanised and automated reasoning, decision procedures - spatio-temporal reasoning, knowledge acquisition, preference and scaling methods - information systems. The predecessors of this conference were held in Dagstuhl (January 1994), Parati (September 1995), Hammamet (January 1997), Warsaw (September 1998), Quebec (January 2000), Dagstuhl (February 2001), Oisterwijk (October 2001), Malente (April 2003), St. Catherines (January 2005), Manchester (September 2006) and Frauenwoerth (April 2008). 2) Program committee Jihad Al'Jaam (Doha, Qatar University) Rudolf Berghammer (Kiel, Germany; Program Co-Chair) Harrie de Swart (Tilburg, Netherlands) Jules Desharnais (Laval, Canada) Rehab Duwairi (Doha, Qatar University) Marcelo Frias (Buenos Aires, Argentina) Hitoshi Furusawa (Kagoshima, Japan) Peter Hoefner (Augsburg, Germany) Ali Jaoua (Doha, Qatar University; General Chair of RelMiCS/AKA 09) Peter Jipsen (Chapman, USA) Wolfram Kahl (McMaster, Canada) Yasuo Kawahara (Kyushu, Japan) Larissa Meinicke (Sydney, Australia) Ali Mili (Tunis, TN, Newark, USA) Bernhard Möller (Augsburg, Germany; Program Co-Chair) Carroll Morgan (Sydney, Australia) Ewa Orlowska (Warsaw, Poland) Susanne Saminger (Linz, Austria) Gunther Schmidt (Munich, Germany) Renate Schmidt (Manchester, UK) Georg Struth (Sheffield, UK) Michael Winter (Brock, Canada) 3) Invited Speakers First Invited Speaker Prof.Dr. H.C.M. de Swart Chair of Logic, Department of Philosophy Tilburg University, Dante building, room 255 P.O. Box 90153, 5000 LE Tilburg The Netherlands Phone: (0031) 13 466 2415 Fax: (0031) 13 4662892 E-mail: H.C.M.deSwart(a)uvt.nl URL: http://www.tilburguniversity.nl/faculties/humanities/dphil/staff/swart/ Second Invited Speaker Prof. Dr. Rohit Parikh Distinguished Professor CS, Math, Philosophy Brooklyn College and CUNY Grad Center USA Phone: 212-817-8197 URL: http://web.cs.gc.cuny.edu/~kgb/ 4) Important Dates Call for Papers: Jan 15 2009 Submission of papers: April 15 2009 Notification: June 20 2009 Final versions due (firm deadline): July 20 2009 Registration Oct. 1 2009 Conference Nov 1-5 2009 5) Proceedings and Submission All papers will be formally reviewed. We plan to publish the proceedings in the series Lecture Notes in Computer Science ready at the conference. The proceedings editors will be R. Berghammer, A. Jaoua and B. Möller. Submissions must be in English, in postscript or pdf format, and provide sufficient information to judge their merits. They must be unpublished and not submitted for publication elsewhere. They may not exceed 15 pages in Springer LNCS style and must be produced with LaTeX. Additional material may be provided by a clearly marked appendix or a reference to a manuscript on a website. This may be considered at the discretion of the PC. Deviation from these requirements may cause immediate rejection. One author of each accepted paper is expected to present the paper at the conference. Detailed instructions for electronic submission can be found at the conference website. Formatting instructions and the LNCS style files can be obtained via http://www.springer.de/comp/lncs/authors.html. As for the earlier conferences of this series, it is also intended to publish a selection of the best papers in revised and extended form in a special issue of the Journal of Logic and Algebraic Programming (JLAP). 6) Student Programme The conference will be accompanied by a PhD training program. Details will be published in due time in a special call and on the conference website. 7) Venue Doha is the capital city of Qatar. With a population of about 1500.000 inhabitants it is the largest city of Qatar and its economic and cultural center. The city is located on the Persian Gulf. The university of Qatar at Doha was opened in the year 1973. Doha is also home of many international schools. Doha has an international airport that is served by many international (e.g., Turkish Airway, by British Airways from London-Heathrow, Lufthansa from Frankfurt, KLM from Amsterdam and Qatar Airways from New York-JFK and Osaka-Kansai). 8) Organization Ali Jaoua (General chair and local organizer) Rudolf Berghammer and Bernhard Möller (Program co-chairs) Further details can be found under http://www.qu.edu.qa/RelMiCs11/

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abc conjecture proved?
by Michael Barr 24 Jan '09

24 Jan '09

Although this has nothing to do with categories, it should be of interest to all mathematicians. According to this: http://groups.google.com/group/sci.math.research/browse_thread/thread/43d73… someone is claiming proof of the abc conjecture by adapting somehow the valid proof for polynomial rings F[x] over a field that uses formal differentiation (this can be found, e.g. in Lang's Algebra). The abc conjecture easily implies the Fermat Last Theorem as well as a number of generalizations (such as the impossibility x^n + y^m = z^p with obvious exceptions) and more. It would be an astounding result. Michael

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WGP'09: Workshop on Generic Programming Call for Papers
by Jeremy Gibbons 23 Jan '09

23 Jan '09

ACM SIGPLAN Workshop on Generic Programming 2009 Edinburgh, UK, August 30, 2009 http://wiki.portal.chalmers.se/cse/WGP09 Goals of the workshop Generic programming is about making programs more adaptable by making them more general. Generic programs often embody non-traditional kinds of polymorphism; ordinary programs are obtained from them by suitably instantiating their parameters. In contrast with normal programs, the parameters of a generic program are often quite rich in structure; for example they may be other programs, types or type constructors, class hierarchies, or even programming paradigms. Generic programming techniques have always been of interest, both to practitioners and to theoreticians, and for at least 20 years generic programming techniques have been a specific focus of research in the functional and object-oriented programming language communities. Generic programming has gradually spread to more and more mainstream languages and is today widely used also in industry. This workshop will bring together leading researchers and practitioners in generic programming from around the world, and feature papers capturing the state of the art in this important area. We welcome contributions on all aspects, theoretical as well as practical, of * adaptive object-oriented programming, * aspect-oriented programming, * concepts (as in the STL / C++ sense) * component-based programming, * generic programming, * meta-programming, * polytypic programming, * programming with modules, * and so on. Organisers: Chair Patrik Jansson, CSE.Chalmers.se co-Chair Sibylle Schupp, STS.TUHH.de Programme Committee: Edwin Brady, U. of St Andrews, Peter Gottschling, TU Dresden Patrik Jansson, Chalmers Chair Barry Jay, U. of T., Sydney Jaakko J=E4rvi, Texas A&M Oleg Kiselyov, FNMOC Andres L=F6h, Utrecht U. Fritz Ruehr, Willamette U. Sibylle Schupp, TU Hamburg Harburg, Co-Chair Marcin Zalewski, Chalmers, We plan to have formal proceedings, published by the ACM. Submission details Deadline for submission: Sunday 090510 Notification of acceptance: Monday 090601 Final submission due: Tuesday 090616 Workshop: Sunday 090830 Authors should submit papers, in postscript or PDF format, formatted for A4 paper, to the WGP09 EasyChair instance by 10th of May 2009. The length should be restricted to 12 pages in standard (two-column, 9pt) ACM format. Accepted papers are published by the ACM and will additionally appear in the ACM digital library. History of the Workshop on Generic Programming This year: * Edinburgh, UK 2009 (affiliated with ICFP09) Earlier Workshops on Generic Programming have been held in * Victoria, BC, Canada 2008 (affiliated with ICFP), * Portland 2006 (affiliated with ICFP), * Utrecht 2005 (informal workshop), * Dagstuhl 2002 (IFIP WG2.1 Working Conference), * Nottingham 2001 (informal workshop), * Ponte de Lima 2000 (affiliated with MPC), * Marstrand 1998 (affiliated with MPC). There were also (closely related) DGP workshops in Oxford (June 3-4 2004), and a Spring School on DGP in Nottingham (April 24-27 2006, which had a half-day workshop attached). Additional information: The WGP steering committee consists of J Gibbons, R Hinze and J Jeuring. Jeremy.Gibbons(a)comlab.ox.ac.uk, Deputy Director Oxford University Computing Laboratory, TEL: +44 1865 283508 Wolfson Building, Parks Road, FAX: +44 1865 283531 Oxford OX1 3QD, UK. URL: http://www.comlab.ox.ac.uk/people/Jeremy.Gibbons

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Re: Request to referee the manuscript no. ER-29
by Michael Barr 23 Jan '09

23 Jan '09

I do not do free work for journals published by publishers who make enormous profits and pay nothing in return either to the authors or reviewers. In choosing to publish your proccedings in such a journal rather than in the many journals that charge between 0 and and a tenth what Elsevier does, you have chosen a path that ultimately would lead to the destruction of scholarship. It is insulting to ask me to cooperate in such a venture. Sincerely yours, Michael Barr On Fri, 23 Jan 2009, Advances in Set-Theoretic Topology, the Organizing Committee wrote: > > Dear Professor Barr, > > We would like to ask you to referee the enclosed manuscript that has been > submitted for possible publication in the Special Issue of the journal > "Topology and its Applications" dedicated to the Proceedings of the > Conference "Advances in Set-Theoretic Topology" (in Honour of Tsugunori > Nogura on his 60th Birthday). > > In order to facilitate timely processing of the whole volume of the > proceedings, we would appreciate having a referee report by April 20, 2009. > > Please, let us know by the return e-mail whether you are willing to referee > this manuscript. If you are unable to referee this paper, we would appreciate > it very much if you could kindly indicate us three people who in your opinion > could serve as ponential referees for this article. > > We are looking forward to your feedback on our request by January 31. > > Best Wishes, > > ---- > > Szymon Dolecki (Burgundy University, France) > Yasunao Hattori (Shimane University, Japan) > Dmitri Shakhmatov (Ehime University, Japan) > Gino Tironi (University of Trieste, Italy) > > Guest Editors of the Special Issue of > "Topology and its Applications" > dedicated to the Proceedings of the Conference > "Advances in Set-Theoretic Topology" > (in Honour of Tsugunori Nogura on his 60th Birthday) > > erice(a)dmitri.math.sci.ehime-u.ac.jp >

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terminology in definitions of limits
by peasthope＠shaw.ca 22 Jan '09

22 Jan '09

Folk, Each definition of a limit which I've seen contains something I would describe as a "probe object" or "test object". The definition of map object in L&S page 313 for example, has X with a criterion asserted for every object X in the category. Is there any sense in my terminology? Thanks, ... Peter E.

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