September 2002 - Categories - categories.org.au

post doc at Leicester
by V. Schmitt 27 Sep '02

27 Sep '02

Dear all, to advert a post-doc position in Leicester. Anybody interested could contact me. Best regards, Vincent Schmitt.

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preprint: Galois theory of simplicial complexes (again)
by grandis＠dima.unige.it 27 Sep '02

27 Sep '02

the abstract I sent to "categories" lost a few sentences... Best regards Marco ___ The following preprint is available: M. Grandis - G. Janelidze Galois theory of simplicial complexes Dip. Mat. Univ. Genova, Preprint 459 (2002), 9 p. Abstract We examine basic notions of categorical Galois theory for the adjunction (\Pi_0 -| discrete) in the case of simplicial complexes. Covering morphisms are characterized as the morphisms satisfying the unique simplex lifting property and are classified by means of the fundamental groupoid, for which we give an explicit "Galois-theoretic" description. The class of covering morphisms is a part of a factorization system similar to the (purely inseparable, separable) factorization system in classical Galois theory, which however fails to be the (monotone, light) factorization. http://www.dima.unige.it/~grandis/rec.public_grandis.html ftp://www.dima.unige.it/Home/grandis/public/GalSmc.pdf With best regards Marco Grandis Dipartimento di Matematica Universita' di Genova via Dodecaneso 35 16146 GENOVA, Italy e-mail: grandis(a)dima.unige.it tel: +39.010.353 6805 fax: +39.010.353 6752 http://www.dima.unige.it/~grandis/ ftp://www.dima.unige.it/Home/grandis/public/ 16-Sep-2002 11:47:46 -0300,4471;000000000001-00000000

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The Scottfest
by Steve Awodey 26 Sep '02

26 Sep '02

*************************************************** The Scottfest in honor of Dana S. Scott on his 70th Birthday *************************************************** There will be a day-long conference on: Saturday 12 October 2002 in Baker Hall A53, Carnegie Mellon University. Speakers include: Clark Glymour, Klaus Sutner, Stephen Brookes, James Cummings, Nuel Belnap, Frank Pfenning, Steve Awodey, Bob Harper, Rick Statman, Jay Kadane All are welcome to attend, no registration is required. The Scottfest is being sponsored jointly by the departments of Computer Science, Mathematics, and Philosophy, Carnegie Mellon University. For more information, consult: http://www.andrew.cmu.edu/~awodey/colloquium/scottfest.html 27-Sep-2002 12:31:10 -0300,2044;000000000000-00000000

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preprint: Galois theory of simplicial complexes
by grandis＠dima.unige.it 23 Sep '02

23 Sep '02

The following preprint is available: M. Grandis - G. Janelidze Galois theory of simplicial complexes Dip. Mat. Univ. Genova, Preprint 459 (2002), 9 p. Abstract We examine basic notions of categorical Galois theory for the adjunction (\Pi_0 -| discrete)means of the fundamental groupoid, for which we give an explicit "Galois-theoretic" description. The class of covering morphisms is a part of a factorization system similar to the (purely inseparable, separable) factorization system in classical Galois theory, which however fails to be the (monotone, light) factorization. http://www.dima.unige.it/~grandis/rec.public_grandis.html ftp://www.dima.unige.it/Home/grandis/public/GalSmc.pdf With best regards Marco Grandis Dipartimento di Matematica Universita' di Genova via Dodecaneso 35 16146 GENOVA, Italy e-mail: grandis(a)dima.unige.it tel: +39.010.353 6805 fax: +39.010.353 6752 http://www.dima.unige.it/~grandis/ ftp://www.dima.unige.it/Home/grandis/public/ 26-Sep-2002 11:31:24 -0300,1487;000000000000-00000000

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CFP: Logic and Games in Multi-Agent Systems
by Peter McBurney 18 Sep '02

18 Sep '02

With apologies for cross-postings Symposium on Logic in Games and Multiagent Systems University of Liverpool, UK, 16 & 17 December, 2002. http://www.csc.liv.ac.uk/~pauly/logamas.html Introduction: Over the past decade, there has been increasing interest in the relationship between logic and game theory. On the one hand, logic researchers find in game theory a natural set of concepts for expressing many logical concepts -- game theoretic interpretations of quantification is perhaps the best-known example. On the other hand, game theorists have found in various logics natural and powerful tools through which to represent and reason about many game-theoretic concepts. Examples include the use of logics of knowledge and common knowledge to capture such notions as perfect information and perfect recall, and the use of strategic/coalition modalities to capture such notions as effectivity. Research into logic and game theory has recently received a substantial boost by the emergence of the multiagent systems paradigm. Multiagent systems research is concerned with the theory and practice of computer systems composed of multiple, interacting, autonomous computing elements known as agents. The multiagent systems paradigm seems an appropriate one through which to model, and understand large-scale distributed/open systems such as the Internet. The multiagent systems community has a significant degree of success in the design of algorithms and techniques that automated, self-interested software agents can use to cooperate, coordinate, and reach agreements on matters of common interest. Much of this work has taken inspiration from the logic and game theory communities. The symposium aims at bringing together researchers working at the intersection of logic, game theory and multiagent systems, in order to identify the key issues, problems, and techniques in the application of logic to games and multiagent systems. Conferences with a related subject area are LOFT, TARK, and LGS. TOPICS OF INTEREST (include but are not limited to): modal logics, e.g. epistemic logic, dynamic logic, game logic, (alternating) temporal logic, coalition logic, etc. communication and information flow belief revision and formation, learning logical foundations, e.g., of solution concepts bounded rationality the role of language in games computational complexity Submission information and further details available at: http://www.csc.liv.ac.uk/~pauly/logamas.html **************************************************************** Dr Peter McBurney Department of Computer Science University of Liverpool Liverpool L69 7ZF U. K. Tel: + 44 151 794 6760 Email: P.J.McBurney(a)csc.liv.ac.uk Web page: www.csc.liv.ac.uk/~peter/ **************************************************************** 18-Sep-2002 15:53:14 -0300,2052;000000000000-00000000

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Workshop on Categorical Structures for Galois Theory, Hopf algebras and Semiabelian Categories]
by Walter Tholen 17 Sep '02

17 Sep '02

Dear Categorist - Below I forward some generic information on the up-coming Workshop at the Fields Institute in Toronto next week. Last-minute decision makers may still register on site on Monday morning (September 23), before the Opening at 8:45am. Walter Tholen. > Workshop on Categorical Structures for Descent and Galois > Theory, Hopf Algebras and Semiabelian Categories > September 23-28, 2002. > > For an updated workshop schedule, please refer to: > www.fields.utoronto.ca/programs/scientific/02-03/galois_and_hopf/sched > ule.html > > Location: The Fields Institue, 222 College Street, 2nd Floor, Toronto. > The Institute is on the north side of College, just West of St. George > Street, between University Avenue and Spadina. The building is three > blocks West of the Queen's Park subway station on the Yonge-University > subway line. A map of the University of Toronto campus can be found > here: > http://oracle.osm.utoronto.ca/map/index2.html > > Meter parking is available across the College St. from the Institute, > and underground around the corner on Huron Street, the first street > West of the Institute. > > You can pick up your meeting package on arrival at the Institute. > Registration will be held from 8:00-8:45am on Monday, September 23, > 2002. > > Coffee and light refreshments will be served during registration the > first day, and every morning from 8:30-9:00 am. There will also be an > afternoon tea break every day from 3-3:30 pm. On Wednesday, September > 25, there will be an excursion to Niagara Falls, where a bag lunch > will be provided for the bus, and dinner served in Niagara Falls. A > reception and banquet will be held on Thursday, September 26, from > 7:00-9:30 pm at the University of Toronto Faculty Club. If you are > vegetarian or have other dietary restrictions, please let the staff at > the Fields Institute know in advance. > > Email can be accessed through computers at Fields. Telephone > messages, during the workshop, can be left with myself at (416) > 348-9710 x 3018. > > The Fields Institute website contains a visitor information section, > which you may want to consult: www.fields.utoronto.ca/resources/ > If you are interested in activites in the Toronto area during your > visit, this website contains up-to-date event and entertainment > listings: > www.toronto.com > > Please contact me if you have any questions or concerns. We are > looking forward to your participation in the workshop. > > Jonathan Kassian > Program Coordinator > The Fields Institute > Tel: (416) 348-9710 x3018 > Fax: (416) 348-9759 18-Sep-2002 15:53:14 -0300,1113;000000000000-00000000

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category theory application to database implementation
by Galchin Vasili 17 Sep '02

17 Sep '02

Hello CT community, Perhaps my question is too much of an applied question. I found a Web site where they say the following: "The category theory may become the core part of the mathematical instrument for the conceptual systems development. The system can be presented as a category in which the relative correlation exists among the objects (morphisms). Each system must be presented both on generalized and concrete reflection levels. The generalized level (upper level) and each of the concrete reflection levels are categories. Hence, it should be considered the process of reflection between general and concrete levels (functors). Each objects of the category system can be a system by itself (category). Consequently we have to consider lattice dependence of categories both on the generalized level and as well as on the decomposition of the objects. Each system changes in time. So it should be considered problems related to the dynamics of categories. Complex consideration and decisions of the above-stated and other related problems should ensure the formation of the mathematical base. This will enable to consider the creation of dynamic, unified distributed databases that can be used in various applied fields." What is this trying to say? Regards, Bill Halchin --------------------------------- Do you Yahoo!? Yahoo! News - Today's headlines --0-1797606253-1031952773=3D:84530 Content-Type: text/html; charset=3Dus-ascii Hello CT community,      Perhaps my question is too much of an applied q= uestion. I found a Web site where they say the following: "The category theory may become the core part of t= he mathematical instrument for the conceptual systems development. The syst= em can be presented as acategory in which the relative correlation exists a= mong the objects (morphisms). Each= system must be presented both on generalized and concrete reflection level= s. The generalized level (upper level) and each of the concrete reflection = levels are categories. Hence, it should be considered the process of reflec= tion between general and concrete levels (functors). Each objects of the category system can be a system by = itself (category). Consequently we have to consider lattice dependence of c= ategories both on the generalized level and as well as on the decomposition= of the objects. Each system chang= es in time. So it should be considered problems related to the dynamics of = categories. Complex consideration = and decisions of the above-stated and other related problems should ensure = the formation of the mathematical base. This will enable to consider the cr= eation of dynamic, unified distributed databases that can be used in variou= s applied fields." What is this trying to say? Regards, Bill Halchin   <hr size=3D1>Do y= ou Yahoo!? <a href=3D"http://news.yahoo.com/">Yahoo! News</a> - Today's headlin= es --0-1797606253-1031952773=3D:84530-- 18-Sep-2002 08:37:05 -0300,3366;000000000000-00000000

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Forwarded mail...
by Robert Rosebrugh 16 Sep '02

16 Sep '02

>>From cat-dist(a)mta.ca Mon Sep 16 13:05:22 2002

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Braided Monoidal Categories
by N Ghani 16 Sep '02

16 Sep '02

For some rather obscure reason, I'd like to read about braided monoidal categories and, in particular, their associated coherence problems. Can someone provide me with a reference or two please? Yours, Neil 16-Sep-2002 17:03:11 -0300,10228;000000000001-00000000

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None
by cat-dist＠mta.ca 16 Sep '02

16 Sep '02

ep 2002 14:32:53 PDT

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