January 2006 - Categories - categories.org.au

horizontal composition
by Susan Niefield 02 Feb '06

02 Feb '06

Does anyone know of a reference for the following definition of a bicategory? The primitive composites are: gf for composable 1-cells GF for vertically composable 2-cells f*G and F*g for horizontally composable pairs of each with appropriate axioms including (G*f')(g*F)=(g'*F)(G*f), for F:f->f':X->Y and G:g->g':Y->Z. The horizontal composite G*F is defined to be the common value of the two vertical composites. -Susan

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universal algebra and diagrammatic reasoning
by John Baez 30 Jan '06

30 Jan '06

Hi - I hope to see some of you in Marseille for Geocal06! I'll be talking about "universal algebra and diagrammatic reasoning", and there's a bunch of lecture notes here: http://math.ucr.edu/home/baez/universal/ Abstract: Since the introduction of category theory, the old subject of "universal algebra" has diversified into a large collection of frameworks for describing algebraic structures. These include "monads" (formerly known as "triples"), the "algebraic theories" of Lawvere, and the "PROPs" of Boardman and Vogt. We give an overview of these different frameworks, which are closely related, and explain how one can reason diagrammatically about algebraic structures defined using them. We focus on the bar construction and the relation between algebraic theories and PROPs. (I feel guilty for not talking about operads... I'll do it if there's time!) Best, jb

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Midlands Graduate School
by mgs2006＠mcs.le.ac.uk 30 Jan '06

30 Jan '06

[Apologies for multiple copies] ************************************************************* Midlands Graduate School 2006 in the Foundations of Computing ************************************************************* http://www.cs.le.ac.uk/~mgs2006 The Midlands Graduate School is taking place 8 - 12 April 2006 at the University of Leicester, UK. The School provides an intensive course of lectures on the Foundations of Computing. It is very well established, having run annually for the past six years, and has always proved a popular and successful event. This year we have Luke Ong, Oxford University and Thomas Streicher, Darmstadt University as guest lecturers. The lectures are aimed at graduate students, typically in their first or second year of study for a PhD. However, the school is open to anyone who is interested in learning more about mathematical computing foundations, and we especially invite participants from UK universities and from sites participating in the APPSEM working group. Foundational courses: R Crole Leicester Operational Semantics P Levy Birmingham Typed Lambda Calculus D Pattinson Leicester Category Theory Advanced courses: T Altenkirch Nottingham Quantum Programming M Escardo Birmingham Operational Domain Theory & Topology H Nilsson Nottingham Advanced Functional Programming L Ong Oxford Game Semantics T Streicher Darmstadt Constructive Logic E Tuosto Leicester Concurrency We expect to have some grants for UK students, while APPSEM funds can be used to support students from APPSEM affiliated sites. For further details and registration please visit http://www.cs.le.ac.uk/~mgs2006 Please register soon! Places and accommodation will be allocated on a first-come, first-serve basis. Roy Crole Alexander Kurz Dirk Pattinson

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An International Symposium Celebrating the 100th Birthday of Kurt =
by cat-dist＠mta.ca 26 Jan '06

26 Jan '06

G=F6del From: goedel2006(a)logic.at Message-Id: <E1F27Vf-0001GD-00(a)gamma.logic.tuwien.ac.at> Sender: cat-dist(a)mta.ca Precedence: bulk Horizons of Truth Logics, Foundations of Mathematics, and the Quest for Understanding the Nature of Knowledge. G=F6del Centenary 2006 An International Symposium Celebrating the 100th Birthday of Kurt G=F6del 27.-29. April 2006 Festsaal of the University of Vienna Organized by the Kurt G=F6del Society The Symposium will take place April 27- 29 in the Celebration Hall of the University of Vienna, famous for its architectural beauty and Gustav Klimt murals. More than 20 lectures by eminent scientists in the fields of logics, mathematics, philosophy, physics, cosmology, and theology will provide new insights into the life and work of Kurt G=F6del and their implications for future generations. A young researcher's competition will allow 10 young researchers to present their projects to an eminent audience, the awards being presented at Belvedere Palace on Friday, April 28, Kurt G=F6del's 100th birthday. The first prize in the amount 20 000 EUR will be awarded to the best project, followed by two additional prizes of 5000 EUR each. A poster session, containing presentations of selected posters will be held in the Small Celebration Hall, and the Senate Hall of the University of Vienna. The poster volume will be published by the Kurt G=F6del Society after the Symposium and sent to all authors. An exhibition on G=F6del life and work will be held in the old library of the University of Vienna throughout the Symposium. Honorary Chair: Gaisi Takeuti, University of Tsukuba, President of the Kurt G=F6del Society Invited Speakers: John D. Barrow, University of Cambridge Gregory J. Chaitin, IBM Thomas J. Watson Research Center, New York Paul Cohen, Stanford University Jack Copeland, University of Canterbury, New Zealand George Ellis, University of Cape Town Solomon Feferman, Stanford University Harvey Friedman, Ohio State University Ivor Grattan-Guinness, Middlesex University Petr Hajek, Academy of Sciences of the Czech Republic Juliette Kennedy, University of Helsinki Ulrich Kohlenbach, Darmstadt University of Technology Georg Kreisel, Royal Society Angus John Macintyre, Royal Society Piergiorgio Odifreddi, University of Turin Christos H. Papdimitiriou, University of California, Berkeley Roger Penrose, University of Oxford Hilary Putnam, Harvard University Wolfgang Rindler, University of Texas, Dallas Dana Scott, Carnegie Mellon University Avi Wigderson, Institute for Advanced Study, Princeton Hugh Woodin, University of California, Berkeley Invited Presentation: Andrei Voronkov, University of Manchester and Microsoft Web and registration: <http://www.logic.at/goedel2006/>http://www.logic.at/goedel2006/

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CT 2006: student support and registration
by selinger＠mathstat.dal.ca 24 Jan '06

24 Jan '06

CALL FOR PARTICIPATION International Category Theory Conference CT 2006 June 25 - July 1, 2006 White Point, Nova Scotia http://www.mathstat.dal.ca/~selinger/ct2006/ * * * IMPORTANT NEWS CONTAINED IN THIS ANNOUNCEMENT: * invited speakers * graduate student support (application deadline Feb 15!) * submission of abstracts (deadline Feb 27!) * registration is now open * arrival and departure information * airport information The International Category Theory Conference (CT) covers all areas of pure and applied category theory. Topics of interest include, but are not limited to: higher dimensional categories, categorical logic, applications of categories in algebra, topology, combinatorics, and other areas of mathematics, applications of category theory to computer science, physics and other mathematical sciences. Previous meetings in this series were held in Vancouver (2004), Como (2000), Coimbra (1999), Vancouver (1997), Halifax (1995), Tours (1994), Isle of Thorns (1992), Montreal (1991), and Como (1990). CT 2006 will be held at White Point Beach Resort (http://www.whitepoint.com/) a seaside resort in Nova Scotia (Canada), about 100 minutes' drive from Halifax. It will be an active research-oriented conference, in something of an "Oberwolfach style". All those interested in category theory and its applications are welcome. INVITED SPEAKERS: ***NEW*** The scientific committee has chosen five invited speakers, of whom the following four have already confirmed their participation: Kathryn Hess (EPF Lausanne) Steve Lack (University of Western Sydney) Tom Leinster (University of Glasgow) Peter Selinger (Dalhousie University) GRADUATE STUDENT SUPPORT: ***NEW*** Please encourage your graduate students to attend this conference. A limited amount of funding will be available to support the participation of graduate students. Students wishing to apply for this money should contact the organizers at ct06(a)mathstat.dal.ca by FEBRUARY 15, and include the following information: 1. A one-page email letter stating your background as well as why you are interested in attending the conference. 2. The letter should also describe any other sources of funding available to you to attend. 3. An email letter of reference from your supervisor or an appropriate other person. TO GIVE A TALK: Prospective speakers should submit an abstract of up to one page. Abstracts should be sufficiently detailed to allow the scientific committee to assess the merits of the work. Submissions should be in plain text, Postscript, or PDF format, and must be sent to ct06(a)mathstat.dal.ca by FEBRUARY 27. Receipt of all submissions will be acknowledged by return email. Authors will be notified by March 30 of the acceptance of their talks. REGISTRATION: ***NEW*** Registration is now open. The registration fees for CT 2006 are as follows: If registering by March 1 (early registration): Regular -- $120 Reduced (*) -- $75 If registering after March 1 (late registration): Regular -- $150 Reduced (*) -- $100 (*) the reduced registration fee applies to students, postdocs, and researchers without grant. There are two easy methods to register for CT 2006. The preferred method is to use our secure online registration form, which allows you to pay the registration fee by credit card: https://sigma.mathstat.dal.ca/~selinger/ct2006/registration.php An alternate paper registration form is also available on the same website, for those who wish to fax or mail their registration and payment. Please remember that, in addition to registering, you also need to reserve your accomodations with White Point Beach Resort. See the conference website for details. ACCOMMODATIONS, ARRIVAL, DEPARTURE: ***IMPORTANT*** Please book your rooms at White Point Beach Resort as soon as possible. We encourage all participants to book this by the end of January; keep in mind that it can be canceled later for a $5 fee. The normal arrival date is Sunday, June 25, and the normal departure date is Saturday, July 1. There will be an informal opening reception / buffet dinner on June 25 from 6:30-10:30pm. The normal check-in time is 2pm and check-out time is 11am. If you need to make special arrangements for early arrival or late departure, please make them by contacting White Point directly. The conference venue offers a choice of accommodation, both in comfortable finished cabins and in "hotel-style" rooms. All meals are included in the price of the rooms. Subject to availability, White Point Beach Resort has agreed to extend the conference rates to the weeks before and after the conference in case any guests wish to stay longer. If you would like to arrange this, please contact White Point directly. For reservations, please contact White Point Beach Resort: Tel: 1-800-565-5068 (U.S. and Canada) Tel: +1-902-354-2711 (international) Fax: +1-902-354-7278 Email reservations: greatday(a)whitepoint.com AIRPORT TRANSPORTATION: ***NEW*** We will arrange for shared transportation between Halifax International Airport and White Point Beach Resort on the days of arrival and departure, at no extra charge to conference participants and their guests. To take advantage of this, please let us know, at ct06(a)mathstat.dal.ca, your arrival and departure times, airline, and flight numbers, as soon as you have this information. Please note that White Point Beach Resort is 100 minutes driving distance from the airport, and there is no convenient alternative transportation available except for renting a car. IMPORTANT DEADLINES: Jan 25, 2006: early booking of rooms Feb 15, 2006: application for graduate student support Feb 27, 2006: submission of abstracts Mar 1, 2006: early registration Mar 30, 2006: notification of authors Apr 20, 2006: registration SCIENTIFIC COMMITTEE: Jiri Adamek John Baez Michael Barr Eugenia Cheng Maria Manuel Clementino Marcelo Fiore Peter Freyd Jonathon Funk Peter Johnstone Steve Lack Susan Niefield Phil Scott Ross Street Walter Tholen (chair) Enrico Vitale ORGANIZERS: Robert Dawson (rdawson(a)cs.stmarys.ca) Dorette Pronk (pronk(a)mathstat.dal.ca) Peter Selinger (selinger(a)mathstat.dal.ca) CONFERENCE EMAIL AND WEBSITE: ct06(a)mathstat.dal.ca http://www.mathstat.dal.ca/~selinger/ct2006/

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Fuzzy categories
by Steve Stevenson 24 Jan '06

24 Jan '06

This seems like a natural idea. But the American Math Soc web site has no listings. What is a fundamental reference? -- steve steve(a)cs.clemson.edu

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book and preprints available
by Marta Bunge 24 Jan '06

24 Jan '06

Dear colleagues, The following recent preprints (including a book) are available in my (updated) homepage http://www.math.mcgill.ca/bunge Marta Bunge and Jonathon Funk, Topos Distributions and Singular Coverings. Book. Submitted to Springer Lecture Notes in Mathematics. http://www.math.mcgill.ca/bunge/s.ps Marta Bunge and Jonathon Funk, "Quasicomponents in Topos Theory: the Hyperpure, Complete Spread Factorization". To appear in Mathematical Proceedings of the Cambridge Philosophical Society. http://www.math.mcgill.ca/bunge/mpcps.ps Marta Bunge and Jonathon Funk, "An Intrinsic Characterization of Branched Coverings". To appear in the Streetfest Proceedings, possibly in Contemporary Mathematics, AMS. http://www.math.mcgill.ca/bunge/intrinsic.ps Comments to either one of us (jfunk(a)uwichill.edu.bb, marta.bunge(a)mcgill.ca) are welcome. Greetings, Marta Bunge ************************************************ Marta Bunge Professor Emerita Dept of Mathematics and Statistics McGill University 805 Sherbrooke St. West Montreal, QC, Canada H3A 2K6 Office: (514) 398-3810 Home: (514) 935-3618 marta.bunge(a)mcgill.ca http://www.math.mcgill.ca/bunge/ ************************************************

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FLoC'06 - Call for Papers
by Kreutzer + Schweikardt 23 Jan '06

23 Jan '06

FLoC'06 - Call for Papers The 2006 Federated Logic Conference Seattle, Washington, USA August 10 -- August 22, 2006 http://research.microsoft.com/floc06/ In 1996, as part of its Special Year on Logic and Algorithms, DIMACS hosted the first Federated Logic Conference (FLoC). It was modeled after the successful Federated Computer Research Conference (FCRC), and synergetically brought together conferences that apply logic to computer science. The second Federated Logic Conference (FLoC'99) was held in Trento, Italy, in 1999, and the third (FLoC'02) was held in Copenhagen, Denmark, in 2002. The Fourth Federated Logic Conference (FLoC'06) will be held in Seattle, Washington, in August 2006, at the Seattle Sheraton (http://www.sheraton.com/seattle) The following conferences will participate in FLoC'06: Int'l Conference on Computer-Aided Verification (CAV) Int'l Conference on Rewriting Techniques and Applications (RTA) IEEE Symposium on Logic in Computer Science (LICS) Int'l Conference on Logic Programming (ICLP) Int'l Conference on Theory and Applications of Satisfiability Testing (SAT) Int'l Joint Conference on Automated Reasoning (IJCAR) In addition, FLoC'06 will host 42 workshops. Pre-conference workshops will be held on August 10-11. LICS, RTA, and SAT will be held in parallel on August 12-15, to be followed by mid-conference workshops and excursions on August 15-16. CAV, ICLP, and IJCAR will be held in parallel on August 16-21, to be followed by post-conference workshops on August 21-22. Plenary events involving all the conferences are planned. Calls for papers for the conferences and workshops are available at the conference website: http://research.microsoft.com/floc06/. We invite you to submit papers to FLoC'06 conferences and workshops. FLoC'06 Steering Committee Moshe Y. Vardi (General Chair) Jakob Rehof (Conference Chair) Edmund Clarke (CAV) Reiner Hahnle (IJCAR) Manuel Hermenegildo (ICLP) Phokion Kolaitis (LICS) Henry Kautz (SAT) Aart Middeldorp (RTA) Andrei Voronkov (IJCAR)

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MFPS 22 Second Call for Papers
by Michael Mislove 22 Jan '06

22 Jan '06

Dear Colleagues, We are now accepting submissions for MFPS 22, which will take place in Genova, Italy on May 24 - 27, 2006. The invited speakers for MFPS 22 include Marcelo Fiore (Cambridge), Eugenio Moggi (Genova), Prakash Panangaden (McGill), Davide Sangiorge (Bologna), Peter Selinger (Dalhousie) and Steve Zdancewic (Penn). In addition, there will be special sessions on security, on timed systems, and on quantum computing. There also will be a Tutorial Day on May 23 on Separation Logic; the lecturers will be Stephen Brookes (CMU), Peter O'Hearn (QMW) and John Reynolds (CMU). Researchers are encouraged to submit papers in programming semantics, its mathematical and logical foundations and related areas, as well as in the areas listed above. Submissions should be made in the form of a PostScript or pdf file thact can be printed on any standard printer. The deadline for submissions is Midnight, Pacific Standard Time, Wednesday, February 22, 2006. More information about the meeting together with precise instructions about submissions can be found at the MFPS 22 web page http://www.math.tulane.edu/~mfps/mfps22.htm Best regards, Mike Mislove =============================================== Professor Michael Mislove Phone: +1 504 862-3441 Department of Mathematics FAX: +1 504 865-5063 Tulane University URL: http://www.math.tulane.edu/~mwm New Orleans, LA 70118 USA ===============================================

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historical query
by jim stasheff 19 Jan '06

19 Jan '06

Does anyone have any information on how Grothendieck's yoga for deformation theory was transmitted to Schlessinger and Deligne? or have a reference as to a published or cahier secret of Grothendieck where it is outlined in his own words? jim

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