From robin at ucalgary.ca Mon Jan 16 18:38:19 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Jan 16 18:38:55 2012 Subject: [Alta-Logic] Peripatetic seminars this term: Wed. 4:00-5:00pm Message-ID: <4F14D10B.8060407@ucalgary.ca> I am going to go ahead and schedule the first seminar this semester at 4:00-5:00pm on Wed. 18th January. If this time does not work for people please let me know and we will have a shot at changing it. The first speaker will be Xuizhan Guo who will give an overview of his PhD. thesis: Time: Wed 18th January, 4:00-5:00pm Place: ICT616 Speaker: Xuizhan Guo Title: Products, Joins, Meets and Ranges in Restriction Categories Abstract: A survey will be given of: 1. The partial product completion for restriction categories. 2. The completeness theorem for join restriction categories in partial map categories using M-adhesive categories and M-gaps. 3. The completeness of meet restriction categories in partial map categories whose M-maps contain the regular monics (and a construction for the meet completion). 4. The generalization of Schein's representation theorem to range categories. -robin From rzach at ucalgary.ca Tue Jan 17 11:42:07 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Tue Jan 17 11:42:49 2012 Subject: [Alta-Logic] Alan Turing Centenary Lecture Series: Alan Turing an the Decision Problem (Jan 24) Message-ID: <1326825727.7034.53.camel@delia> 2012 marks the centenary of Alan Turing, mathematical genius, WWII codebreaker, pioneer of computing, and gay icon. The Departments of Computer Science and Philosophy with support from the Faculties of Arts and Science as well as the Pacific Institute for the Mathematical Sciences are holding a series of lectures on Turing's life and work throughout 2012. ucalgary.ca/turing facebook.com/TuringYYC Alan Turing and the Decision Problem Richard Zach, Department of Philosophy Tuesday, January 24, 4-5:30 pm, ICT 122 http://ucalgary.ca/turing/node/6 Many scientific questions are considered solved to the best possible degree when we have a method for computing a solution. This is especially true in mathematics and those areas of science in which phenomena can be described mathematically: one only has to think of the methods of symbolic algebra in order to solve equations, or laws of physics which allow one to calculate unknown quantities from known measurements. The crowning achievement of mathematics would thus be a systematic way to compute the solution to any mathematical problem. The hope that this was possible was perhaps first articulated by the 18th century mathematician-philosopher G. W. Leibniz. Advances in the foundations of mathematics in the early 20th century made it possible in the 1920s to precisely formulate the question of whether there is such a systematic way to find a solution to every mathematical problem. This became known as the "decision problem", and it was considered a major open problem in the 1920s and 1930s. Alan Turing solved it in his first, groundbreaking paper "On computable numbers" (1936), by showing that no such procedure can exist. In order to do this, Turing had to provide a convincing analysis of what a computational procedure is. His abstract, mathematical model of computability is now known as the Turing Machine model of computation. From robin at ucalgary.ca Mon Jan 30 14:01:53 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Jan 30 14:02:33 2012 Subject: [Alta-Logic] Peripatetic talk by Yuri Matiyasevich 2nd Feb Message-ID: <4F270541.8070600@ucalgary.ca> Time: 3:30pm, 2nd Feb, 2012 Place: ICT 616 (N.B. we may move, at the time, to a larger venue if it is clear many more people want to come than fit in the room!) Speaker: Yuri Matiyasevich Title: Computation Paradigms in the Light of Hilbert's Tenth Problem From robin at ucalgary.ca Mon Jan 30 18:34:34 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Jan 30 18:35:13 2012 Subject: [Alta-Logic] CORRECTION: Peripatetic talk by Yuri Matiyasevich **29th Feb** Message-ID: (Apologies for getting your hopes up and for announcing this 27 days too early! Correction below!) Time: 3:30pm, 29th Feb, 2012 Place: ICT 616 (N.B. we may move, at the time, to a larger venue if it is clear many more people want to come than fit in the room!) Speaker: Yuri Matiyasevich Title: Computation Paradigms in the Light of Hilbert's Tenth Problem -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20120130/5dbba78f/attachment.html From robin at ucalgary.ca Mon Jan 30 18:41:10 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Jan 30 18:41:31 2012 Subject: [Alta-Logic] CORRECTION: Peripatetic talk by Yuri Matiyasevich **29th Feb** Message-ID: <4F2746B6.40703@ucalgary.ca> (Apologies for getting your hopes up and for announcing this talk 27 days too early! Correction below!) Time: 3:30pm, 29th Feb, 2012 Place: ICT 616 (N.B. we may move, at the time, to a larger venue if it is clear many more people want to come than fit in the room!) Speaker: Yuri Matiyasevich Title: Computation Paradigms in the Light of Hilbert's Tenth Problem -robin From robin at ucalgary.ca Mon Feb 6 11:24:03 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Feb 6 11:25:18 2012 Subject: [Alta-Logic] Peripatetic seminar: Berndt Brenken continues Message-ID: <4F301AC3.8080202@ucalgary.ca> Speaker: Berndt Brenken Time: 3:30pm, Wednesday, 7th February, 2012 Place: ICT616 Title: Linear contractions Abstract: The unital universal operator algebra generated by a contraction is considered; for example we show it is contractible and explore its close connection with the universal operator algebra of a partial isometry. This talk continues from my recent talk on partial isometries but does not depend on it. From rzach at ucalgary.ca Mon Feb 6 22:32:39 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Mon Feb 6 22:32:59 2012 Subject: [Alta-Logic] UofA Philosophy Colloquium: Feb. 9, Katalin Bimbo on Ticket Entailment In-Reply-To: References: Message-ID: <1328592759.1908.16.camel@keiko> UofA PHILOSOPHY COLLOQUIUM On Thursday, February 9 at 3:30 p.m. in Assiniboia Hall 2-02A Katalin Bimb? (University of Alberta) will be speaking on ?A Solution to a 50-Year-Old Problem? ALL WELCOME Abstract: The logic of ticket entailment was introduced by A. R. Anderson in the early 1960s. A logic is decidable if and only if the set of its theorems is recursive. Some relevance logics are known to be decidable, whereas others have been shown to be undecidable. I will present a solution to the famous open problem: the decidability of T? (implicational ticket entailment). The decision procedure also solves the inhabitation problem of simple types by combinators over the base {B, B?, I, W}. The results presented in this talk come from the following two papers: (1) Bimb?, K. and J. M. Dunn, ?New consecution calculi for R t?? Notre Dame Journal of Formal Logic, (20 pages, to appear). (2) Bimb?, K. and J. M. Dunn, ?On the decidability of implicational ticket entailment," (18 pages, submitted for publication). This research is funded by my SSHRC Standard Research Grant (#410-2010-0207). -------------- next part -------------- A non-text attachment was scrubbed... Name: Bimbo Poster.pdf Type: application/pdf Size: 84002 bytes Desc: not available Url : http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20120206/89527a1a/BimboPoster.pdf From robin at ucalgary.ca Sun Feb 12 18:07:37 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Sun Feb 12 18:08:56 2012 Subject: [Alta-Logic] Peripatetic talk: 15th June by Jason Nicholson Message-ID: <4F386259.7050604@ucalgary.ca> Title: A Perspective on Wigner?s ?Unreasonable Effectiveness of Mathematics? Speaker: Jason Nicholson Place: ICT 616 Time: 3;30pm, 15th Feb 2012 Abstract : Since Eugene Wigner published his article ?The Unreasonable Effectiveness of Mathematics in the Natural Sciences? in 1960, the idea of it has been in the back of the minds of many, especially mathematicians, physicists, and philosophers of science. There have been several responses over the years, but nothing has stood out. A possible reason for this, explored in this talk, is that all explanations are within the paradigm of the subject-object metaphysics commonly used by our culture, and any explanation of this quandary lies beyond such a metaphysics. The metaphysics that will be used here instead, which subsumes subject-object metaphysics, is the broader ?Metaphysics of Quality? as created by Robert M. Pirsig and explained in his two extraordinary books ?Zen and the Art of Motorcycle Maintenance? and ?Lila?. This metaphysics provides a strikingly simple way of understanding Wigner?s observation, as well as insights into several other questions in and around mathematics and physics. From rzach at ucalgary.ca Tue Feb 14 21:14:30 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Tue Feb 14 21:19:59 2012 Subject: [Alta-Logic] Alan Turing Centenary: Turing's Real Machines (Feb 28) Message-ID: <1329279270.17420.45.camel@delia> *** Please distribute! *** 2012 marks the centenary of Alan Turing, mathematical genius, WWII codebreaker, pioneer of computing, and gay icon. The Departments of Computer Science and Philosophy with support from the Faculties of Arts and Science as well as the Pacific Institute for the Mathematical Sciences are hosting a series of lectures on Turing's life and work throughout 2012. http://ucalgary.ca/turing http://facebook.com/TuringYYC Next event: *** Turing's Real Machines *** Michael R. Williams, Department of Computer Science Tuesday, February 28, 4-5:30 pm, Engineering A 201 http://ucalgary.ca/turing/node/4 While Turing is best known for his abstract concept of a "Turing Machine," he did design (but not build) several other machines - particularly ones involved with code breaking and early computers. While Turing was a fine mathematician, he could not be trusted to actually try and construct the machines he designed - he would almost always break some delicate piece of equipment if he tried to do anything practical. The early code-breaking machines (known as "bombes" - the Polish word for bomb, because of their loud ticking noise) were not designed by Turing but he had a hand in several later machines known as "Robinsons" and eventually the Colossus machines. After the War he worked on an electronic computer design for the National Physical Laboratory - an innovative design unlike the other computing machines being considered at the time. He left the NPL before the machine was operational but made other contributions to early computers such as those being constructed at Manchester University. This talk will describe some of his ideas behind these machines. Poster: http://ucalgary.ca/turing/node/22 From rzach at ucalgary.ca Tue Feb 28 10:10:37 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Tue Feb 28 10:16:00 2012 Subject: [Alta-Logic] TODAY! Alan Turing Centenary: Turing's Real Machines Message-ID: <1330449037.1906.34.camel@keiko> *** Turing's Real Machines *** Michael R. Williams, Department of Computer Science Tuesday, February 28, 4-5:30 pm, Engineering A 201 http://ucalgary.ca/turing/node/4 While Turing is best known for his abstract concept of a "Turing Machine," he did design (but not build) several other machines - particularly ones involved with code breaking and early computers. While Turing was a fine mathematician, he could not be trusted to actually try and construct the machines he designed - he would almost always break some delicate piece of equipment if he tried to do anything practical. The early code-breaking machines (known as "bombes" - the Polish word for bomb, because of their loud ticking noise) were not designed by Turing but he had a hand in several later machines known as "Robinsons" and eventually the Colossus machines. After the War he worked on an electronic computer design for the National Physical Laboratory - an innovative design unlike the other computing machines being considered at the time. He left the NPL before the machine was operational but made other contributions to early computers such as those being constructed at Manchester University. This talk will describe some of his ideas behind these machines. Poster: http://ucalgary.ca/turing/node/22 From rzach at ucalgary.ca Mon Mar 5 10:44:09 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Mon Mar 5 10:53:29 2012 Subject: [Alta-Logic] Alan Turing Centenary: Screening of "Breaking the Code" (March 14) Message-ID: <1330969449.2837.4.camel@delia> *** Please distribute! *** 2012 marks the centenary of Alan Turing, mathematical genius, WWII codebreaker, pioneer of computing, and gay icon. The Departments of Computer Science and Philosophy with support from the Faculties of Arts and Science as well as the Pacific Institute for the Mathematical Sciences are hosting a series of events honoring Turing's life and work throughout 2012. http://ucalgary.ca/turing http://facebook.com/TuringYYC Next event: *** Breaking the Code *** Written by Hugh Whitemore Directed by Herbert Wise Wednesday, March 14, 5:30-7 pm, Craigie Hall C 119 http://ucalgary.ca/turing/node/24 Sir Derek Jacobi stars in this 1996 BBC production of Hugh Whitemore's 1986 biographical play. Alan Turing broke the German Enigma code and ultimately helped win WWII, and his theoretical work on computing machines now underpins computer science. His private life was complicated by his truthfulness and openness about his homosexuality at a time when it was illegal. The film paints a moving portrait of Turing's genius and momentous contributions,as well as his struggles with a repressive British society complicated by his involvement with national security. Open to University of Calgary faculty and students only Poster: http://ucalgary.ca/turing/node/25 From robin at ucalgary.ca Mon Mar 5 14:10:58 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Mar 5 14:11:31 2012 Subject: [Alta-Logic] Peripatetic talk Wed. 7th March Message-ID: Speaker: Tristan Jugdev Place; ICT 616 Time: Wed. 7th March 2012 Title: An Introduction to Infinity Categories Abstract: Roughly speaking, an infinity category is a category in which we have 2-morphisms between the regular morphisms, 3-morphisms between those, and in general, n-morphisms between (n-1)-morphisms for arbitrarily large n. In this talk, I will present two geometric model for discussing infinity categories, quasi-categories and simplicially enriched categories, and briefly outline their equivalence. I will then walk through some basic constructions in category theory such as functors, over/under categories and possibly (co)limits in the infinity category setting. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20120305/25b03679/attachment.html From robin at ucalgary.ca Mon Mar 5 14:28:06 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Mar 5 14:28:49 2012 Subject: [Alta-Logic] Re: Peripatetic talk Wed. 7th March, 3:30pm (ommitted the time!!) Message-ID: Ooops ... I forget to mention the time! Speaker: Tristan Jugdev Place; ICT 616 Time: Wed. 7th March 2012, 3:30pm Title: An Introduction to Infinity Categories Abstract: Roughly speaking, an infinity category is a category in which we have 2-morphisms between the regular morphisms, 3-morphisms between those, and in general, n-morphisms between (n-1)-morphisms for arbitrarily large n. In this talk, I will present two geometric model for discussing infinity categories, quasi-categories and simplicially enriched categories, and briefly outline their equivalence. I will then walk through some basic constructions in category theory such as functors, over/under categories and possibly (co)limits in the infinity category setting. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20120305/052337a7/attachment.html From robin at ucalgary.ca Mon Mar 5 15:02:14 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Mar 5 15:02:59 2012 Subject: [Alta-Logic] re: Peripatetic talk Wed. 7th March, 3:30pm (ommitted the time!!) In-Reply-To: References: Message-ID: Ooops ... I forget to mention the time! Speaker: Tristan Jugdev Place; ICT 616 Time: Wed. 7th March 2012, 3:30pm Title: An Introduction to Infinity Categories Abstract: Roughly speaking, an infinity category is a category in which we have 2-morphisms between the regular morphisms, 3-morphisms between those, and in general, n-morphisms between (n-1)-morphisms for arbitrarily large n. In this talk, I will present two geometric model for discussing infinity categories, quasi-categories and simplicially enriched categories, and briefly outline their equivalence. I will then walk through some basic constructions in category theory such as functors, over/under categories and possibly (co)limits in the infinity category setting. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20120305/3cea3300/attachment.html From robin at ucalgary.ca Mon Mar 12 12:15:53 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Mar 12 12:16:31 2012 Subject: [Alta-Logic] Peripatetic Talk (Infinity and quasi-categories) Message-ID: Place: ICT 616 Time: 3:30pm, Wednesday 14th March Speaker: Tristan Jugdev Title: An Introduction to Infinity Categories (continued) Abstract: Roughly speaking, an infinity category is a category in which we have 2-morphisms between the regular morphisms, 3-morphisms between those, and in general, n-morphisms between (n-1)-morphisms for arbitrarily large n. In this talk, I will present two geometric model for discussing infinity categories, quasi-categories and simplicially enriched categories, and briefly outline their equivalence. I will then walk through some basic constructions in category theory such as functors, over/under categories and possibly (co)limits in the infinity category setting. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20120312/50b46327/attachment.html From rzach at ucalgary.ca Tue Mar 13 14:21:54 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Tue Mar 13 14:22:08 2012 Subject: [Alta-Logic] Bernie Linsky on Russell's Paradox, Friday, 4pm Message-ID: <1331670114.2599.4.camel@delia> Reminder: Bernie Linsky (UofA) will give this week's philosophy colloquium: "The Paradox in Russell's Letter to Frege in 1902" Location: Social Sciences Building, Room 1253 About the Talk: Russell wrote to Frege on June 16, 1902, telling him of a "difficulty" which is now famous as "Russell's Paradox". It was already known before 1902 that sets of sets that are not members of themselves lead to contradictions. Zermelo and Hilbert both said that they had anticipated Russell's paradox. Russell didn't direct his argument particularly against Frege's famous "Basic Law V". So, what was Russell's problem? Bernie's paper is attached. Please let me know by Thursday 3pm if you are interested in joining Bernie for dinner after his talk and/or for brunch on Saturday. He has another paper on Ernst Schr?der and Ernst Zermelo's independent discovery of the paradoxes, which we could discuss on Saturday. -------------- next part -------------- A non-text attachment was scrubbed... Name: Russell's.Paradox.of.Predicates.pdf Type: application/pdf Size: 158830 bytes Desc: not available Url : http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20120313/a366663c/Russells.Paradox.of.Predicates.pdf From rzach at ucalgary.ca Thu Mar 22 11:41:12 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Thu Mar 22 11:53:19 2012 Subject: [Alta-Logic] Alan Turing Centenary: Alan Turing and Enigma (John Ferris, March 27) Message-ID: <1332438072.6794.4.camel@delia> *** Please distribute! *** 2012 marks the centenary of Alan Turing, mathematical genius, WWII codebreaker, pioneer of computing, and gay icon. The Departments of Computer Science and Philosophy with support from the Faculties of Arts and Science as well as the Pacific Institute for the Mathematical Sciences are hosting a series of events honoring Turing's life and work throughout 2012. http://ucalgary.ca/turing http://facebook.com/TuringYYC Listen to part one of CJSW Presents on Alan Turing: http://cjsw.com/program/cjsw-presents/alan-turing-episode-1/ Next event: *** Alan Turing and Enigma *** John R. Ferris, Professor of History Tuesday, March 27, 4-5:30 pm, Engineering A 201 http://ucalgary.ca/turing/node/15 Central to Alan Turing's posthumous reputation is his work with British codebreaking during the Second World War. This relationship is not well understood, largely because it stands on the intersection of two technical fields, mathematics and cryptology, the second of which also has been shrouded by secrecy. This lecture will assess this relationship from an historical cryptological perspective. It treats the mathematization and mechanization of cryptology between 1920-50 as international phenomena. It assesses Turing's role in one important phase of this process, British work at Bletchley Park in developing cryptanalytical machines for use against Enigma in 1940-41. It focuses on also his interest in and work with cryptographic machines between 1942-46, and concludes that work with them served as a seed bed for the development of his thinking about computers. Poster: http://ucalgary.ca/turing/node/27 From robin at ucalgary.ca Mon Apr 9 17:34:53 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Apr 9 17:35:13 2012 Subject: [Alta-Logic] Peripatetic talk this Wed.: Jonathan Galligher on rewriting Message-ID: Place: ICT 616 Time: 3:30 pm Wed. 11th April Speaker: Jonathan Gallagher Title: Krivine's presentation of Tait and Martin-L\"{o}f's technique for confluence proofs Abstract: The Church-Rosser theorem states that beta reduction (defined for the lambda calculus) is a confluent relation. Barendregt gives a very simple proof of this theorem, which he attributes to Tait and Martin-L\"{o}f. This proof also generalizes easily to extensions of the lambda calculus. In this talk, we will review Tait and Martin-L\"{o}f's proof technique, and prove the confluence of the lambda calculus. We will then show how to use this proof technique to prove that the differential lambda calculus is confluent. From robin at ucalgary.ca Mon Apr 16 12:42:18 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Apr 16 12:42:41 2012 Subject: [Alta-Logic] Peripatetic seminar: Tangent structure and synthetic differential geometry Message-ID: Time: 18th April, Wednesday 3:00pm Place: ICT 616 (University of Calgary) Speaker: Robin Cockett Title: Tangent structure and synthetic differential geometry Abstract: I am going to describe some aspects of current work with Geoff Cruttwell on tangent structure. A category with tangent structure is an abstract setting for differential geometry. The notion was first proposed by Jiri Rosicky in 1984 in a paper remarkable for its brevity. Rosicky promised a follow on paper which would contain details of proofs, however, it seems that this never happened. Geoff and I stumbled into this area as we were looking for abstract characterizations for categories of differential manifolds. Anders Kock kindly pointed out Rosicky's remarkable paper to us. A particularly, fascinating aspect of Rosiky's paper is that he initiates the attempt to completely characterize synthetic differential geometry (SDG) as "representable" tangent structure. As we had not even seriously considered the possibility that these SDG settings would be included under this sort of abstract formulation, Geoff and I have been scrambling to understand this connection. Approaching SDG though representable tangent structure provides a rather different perspective as to what these models bring to the table and this --together with (I hope) a discussion of a particular model -- will be the main focus of the talk. What seems quite remarkable is that the concept of tangent structure seems to subsumes ALL the notions of differential geometry of which we are aware! From robin at ucalgary.ca Tue Apr 17 14:26:56 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Tue Apr 17 14:27:39 2012 Subject: [Alta-Logic] Re: Peripatetic seminar: Tangent structure and synthetic differential geometry In-Reply-To: References: Message-ID: Responding to popular demand (actually Peter Z.) I am going to move the time forward to 2:00pm I have booked ICT658 which is a rather small room however we may be able to get into the usual room if we are lucky ... -robn > Time: 18th April, Wednesday 3:00pm > > Place: ICT 616 (University of Calgary) > > Speaker: Robin Cockett > > Title: Tangent structure and synthetic differential geometry > > Abstract: > > I am going to describe some aspects of current work with Geoff > Cruttwell on tangent structure. > > A category with tangent structure is an abstract setting for > differential geometry. ?The notion was first proposed by Jiri Rosicky > in 1984 in a paper remarkable for its brevity. ?Rosicky promised a > follow on paper which would contain details of proofs, however, it > seems that this never happened. ? Geoff and I stumbled into this area > as we were looking for abstract characterizations for categories of > differential manifolds. Anders Kock kindly pointed out Rosicky's > remarkable paper to us. > > A particularly, fascinating aspect of Rosiky's paper is that he > initiates the attempt to completely characterize synthetic > differential geometry (SDG) as "representable" tangent structure. ?As > we had not even seriously considered the possibility that these SDG > settings would be included under this sort of abstract formulation, > Geoff and I have been scrambling to understand this connection. > Approaching SDG though representable tangent structure provides a > rather different perspective as to what these models bring to the > table and this --together with (I hope) a discussion of a particular > model -- will be the main focus of the talk. > > ?What seems quite remarkable is that the concept of tangent structure > seems to subsumes ALL the notions of differential geometry of which we > are aware! From robin at ucalgary.ca Mon Apr 23 19:32:30 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Mon Apr 23 19:32:49 2012 Subject: [Alta-Logic] Peripatetic seminar: 25th April, Pavel Hrubes Message-ID: Time: 3:30pm, 25th April 2012 Place: ICT 616 Speaker: Pavel Hrubes Title: Finite consistency statements Abstarct: Godel's incompleteness theorem is arguably the most influential result in mathematical logic. It can be interpreted as saying that syntactic reasoning, and perhaps any reasoning whatsoever, is incomplete. An analogy can be drawn between the incompleteness theorem and questions in computational complexity (such as P=NP), by means of the so-called finite consistency statements. Finite consistency statements roughly assert that a theory does not have a short proof of a contradiction, and I will discuss the question whether the statements have feasible proofs. From robin at ucalgary.ca Tue May 8 14:35:29 2012 From: robin at ucalgary.ca (Robin Cockett) Date: Tue May 8 14:36:40 2012 Subject: [Alta-Logic] Peripatetic talk. Wed 3:30pm ICT 616 Message-ID: Time: 3:30pm, 9th Jan 2012 Place: ICT 616 Speaker: Johnathan Gallagher Title: Rewriting modulo an equivalence relation Abstract: Recently, an analysis of the relationship between local confluence and confluence has produced a very powerful method for proving confluence. This method, called local decreasingness, subsumes all of the confluence criteria currently known. Further, it has a very nice analog for rewriting modulo an equivalence relation. In this talk, we will discuss rewriting modulo an equivalence relation. In particular, we will discuss some of the subtleties with rewriting modulo an equivalence relation. We will see an analog of the Tait and Martin-L?f procedure for rewriting modulo an equivalence relation, and we will see its weakness in this setting. Finally, we will describe the technique of local decreasingness, and why it is a more suitable technique for proving confluence modulo an equivalence relation. From rzach at ucalgary.ca Wed Sep 26 18:47:32 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Wed Sep 26 19:09:44 2012 Subject: [Alta-Logic] Alan Turing Centenary: Alan Turing and the Patterns of Life (Przemyslaw Prusinkiewicz, October 9) Message-ID: <5063A224.1030506@ucalgary.ca> *** Please distribute! *** 2012 marks the centenary of Alan Turing, mathematical genius, WWII codebreaker, pioneer of computing, and gay icon. The Departments of Computer Science and Philosophy with support from the Faculties of Arts and Science as well as the Pacific Institute for the Mathematical Sciences are hosting a series of events honouring Turing's life and work throughout 2012. http://ucalgary.ca/turing http://facebook.com/TuringYYC Watch previous lectures in this series on Mathtube: http://mathtube.org/conference/lecture_video/Alan%20Turing%20Year Listen to part one of CJSW Presents on Alan Turing: http://cjsw.com/program/cjsw-presents/alan-turing-episode-1/ Next event: *** Alan Turing and the Patterns of Life *** Przemys?aw Prusinkiewicz Professor of Computer Science University of Calgary Tuesday, October 9, 4-5:30 pm, ICT 121 http://ucalgary.ca/turing/node/28 In 1952, Turing published his only paper spanning chemistry and biology: "The chemical basis of morphogenesis". In it, he proposed a hypothetical mechanism for the emergence of complex patterns in chemical reactions, called reaction-diffusion. He also predicted the use of computational models as a tool for understanding patterning. Sixty years later, reaction-diffusion is a key concept in the study of patterns and forms in nature. In particular, it provides a link between molecular genetics and developmental biology. The presentation will review the concept of reaction-diffusion, the tumultuous path towards its acceptance, and its current place in biology. Poster: http://ucalgary.ca/turing/files/turing/aty2012prusinkiewicz%20.pdf *** Mark your calendars *** November 6: Alan Turing, the Politics of Sexual Science, and the Making of a Gay Icon (Chris Waters, Williams College) http://ucalgary.ca/turing/node/31 December 4: Turing and Intelligent Machines (Nicole Wyatt, University of Calgary) http://ucalgary.ca/turing/node/32 From rzach at ucalgary.ca Thu Oct 4 10:40:56 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Thu Oct 4 10:41:33 2012 Subject: [Alta-Logic] LOGIC TALK TODAY! Aldo Antonelli (Davis) Message-ID: <506DBC18.6060106@ucalgary.ca> Aldo Antonelli - "Home on the Range: Where Semantics and Ontology Play" Thursday October 4, 4-6 pm Social Sciences Building, Room 1253 About the Talk: In his 1950 dissertation, Leon Henkin showed how to provide higher-order quantifiers with non-standard, or "general" interpretations, in which, for instance, second-order quantifiers are taken to range over collections of subsets of the domain that may fall short of the full power-set. In contrast, first-order quantifiers are usually regarded as immune to this sort of non-standard interpretation, at least in the sense that the semantics for first-order quantifiers is ordinarily taken to be determined once a first-order domain of objects is fixed. After introducing the notion of a general interpretation for arbitrary first-order quantifiers, this talk explores some of the properties of quantifiers so construed, emphasizing the effects of imposing further constraints that the interpretation is to satisfy. The possibility of general interpretations for first-order quantifier bears directly on the viability of the Quinean criterion for ontological commitment, according to which "to be is to be the value of a bound variable". But on the general interpretation, first-order quantifiers are just sa radically semantically indeterminate as their second-order counterparts. It follows that the Quinean criterion ascribing existence to those objects that fall within the range of the quantifiers is neither necessary nor (in an importantly different sense) sufficient for ontological commitment. Aldo Antonelli is Professor of Philosophy at the University of California, Davis. His primary areas of specialization are Logic and Applications, Defeasable Reasoning and Knowledge Representation, Philosophy of Mathematics, Philosophy of Logic, Philosophy of Language, and Early Analytic Philosophy. From rzach at ucalgary.ca Mon Oct 22 11:25:19 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Mon Oct 22 11:25:29 2012 Subject: [Alta-Logic] peripatetic seminar Message-ID: <5085817F.6000402@ucalgary.ca> Greetings, Let's get the peripatetic seminar going this year. Here is a link to a doodle poll so we can coordinate schedules:* http://www.doodle.com/bd5a6ctzp7dqwki6 *I don't know everyone's email address, so please forward this email to anyone who may be interested in attending the seminar. If you are interested in giving a talk, or know someone who would like to give a talk, send me an email. Sincerely, Jonathan ps. Sorry for sending this to individual emails instead of the mailing list, but I am having trouble using the mailing list. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20121022/fa3bbdb9/attachment.html From rzach at ucalgary.ca Mon Oct 29 12:53:49 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Mon Oct 29 12:54:00 2012 Subject: [Alta-Logic] Alan Turing, the Politics of Sexual Science, and the Making of a Gay Icon (Chris Waters, November 6) Message-ID: <508ED0BD.8050404@ucalgary.ca> *** Please distribute! *** 2012 marks the centenary of Alan Turing, mathematical genius, WWII codebreaker, pioneer of computing, and gay icon. The Departments of Computer Science and Philosophy with support from the Faculties of Arts and Science as well as the Pacific Institute for the Mathematical Sciences are hosting a series of events honouring Turing's life and work throughout 2012. http://ucalgary.ca/turing http://facebook.com/TuringYYC Next event: *** Alan Turing, the Politics of Sexual Science, and the Making of a Gay Icon *** Chris Waters Hans W. Gatzke '38 Professor of Modern European History Williams College Tuesday, November 6, 4-5:30 pm, ICT 121 http://ucalgary.ca/turing/node/31 In the 1940s Alan Turing?s homosexuality was an open secret amongst his co-workers at Bletchley Park. In 1952 the secret became widely known when Turing was arrested on charges of ?gross indecency? under the same 1885 law that had led to the imprisonment of Oscar Wilde over half a century earlier. Opting for chemical ?treatment? of his ?condition? rather than imprisonment, Turing was one of many well-known casualties of a heightened drive against homosexuality in a postwar Britain that drew the line between the normal and the deviant more sharply than ever before. In his talk, Chris Waters will discuss Turing?s sexual proclivities and their meanings in the context of his times, focusing in particular on his arrest and subsequent fate in the context of the sexual politics of the first half of the 1950s. In addition, he will discuss the shaping of Turing?s posthumous reputation, beginning with the attempts made by the Gay Liberation Front in the 1970s to render Turing the gay icon he has become today. Poster: http://ucalgary.ca/turing/node/34 http://ucalgary.ca/turing/files/turing/aty2012waters.pdf *** Watch previous lectures in this series on Mathtube *** http://mathtube.org/conference/lecture_video/Alan%20Turing%20Year Listen to the CJSW Presents feature on Alan Turing: http://cjsw.com/program/cjsw-presents/alan-turing-episode-1/ http://cjsw.com/program/cjsw-presents/turing-episode-2/ *** Mark your calendars *** December 4: Turing and Intelligent Machines (Nicole Wyatt, University of Calgary) http://ucalgary.ca/turing/node/32 From jdgall84 at gmail.com Wed Nov 14 12:37:42 2012 From: jdgall84 at gmail.com (Jonathan Gallagher) Date: Wed Nov 14 12:38:03 2012 Subject: [Alta-Logic] Peripatetic Seminar November 20: Peter Zvengrowski Message-ID: Greetings, We have a peripatetic seminar scheduled: Speaker: Peter Zvengrowski Location/Date: ICT 616/Tuesday Nov 20 @ 2 pm Title: Goursat's Lemma with Relations to Geometry and Number Theory Abstract: Goursat's Lemma gives a description of the subgroups of the direct product AxB of two groups, in terms of subgroups of A and B. It originates in a paper written in 1889 by the famed French analyst Edouard Goursat, and was put into its modern form thanks to the work of two Canadian mathematicians, H.S.M. Coxeter and J. Lambek. It can be generalized in several ways, one being to other categories besides groups. Another generalization is to studying the subgroups of AxBxC and higher direct products, this turns out to be surprisingly delicate and was done in joint work with Kristine Bauer and Debasis Sen. This generalization will be the main topic of the talk, and we shall also discuss applications to various families of groups such as abelian, finite, solvable, nilpotent, etc. In particular, the application to cyclic groups involves some number theory, such as the famed theorem of Dirichlet about primes in arithmetic progressions. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20121114/e0e9dd66/attachment.html From jdgall84 at gmail.com Sun Nov 25 11:13:11 2012 From: jdgall84 at gmail.com (Jonathan Gallagher) Date: Sun Nov 25 11:13:32 2012 Subject: [Alta-Logic] peripatetic seminar Message-ID: Greetings, We have another peripatetic seminar scheduled: Speaker: Mike Pors Location: ICT 616 on Tuesday November 27 at 2 pm Title: Simplicial Sets and Homology Abstract: A simplicial set is a nice combinatorial and categorical description of how to assemble a space from the standard n-simplices, $\Delta^n$. As with $\Delta$-sets, constructions using simplicial sets require that faces be glued to faces, a nice condition for proofs, but which does not require that the two faces being glued together be homeomorphic, which allows for more flexibility than $\Delta$-complexes. In this talk, I will give an introduction to the basic theory of simplicial sets and construct some familiar spaces using simplicial sets. Finally, we will look at how, to any simplicial set $X$, we may associate a chain complex $C$, whose homology agrees with the homology on $|X|$, the space constructed from the instructions encoded in $X$. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20121125/038f16fa/attachment.html From rzach at ucalgary.ca Wed Nov 28 11:38:30 2012 From: rzach at ucalgary.ca (Richard Zach) Date: Wed Nov 28 11:38:46 2012 Subject: [Alta-Logic] Turing and Intelligent Machines (Nicole Wyatt, December 4) Message-ID: <50B65A26.9050003@ucalgary.ca> *** Please distribute! *** 2012 marks the centenary of Alan Turing, mathematical genius, WWII codebreaker, pioneer of computing, and gay icon. The Departments of Computer Science and Philosophy with support from the Faculties of Arts and Science as well as the Pacific Institute for the Mathematical Sciences are hosting a series of events honouring Turing's life and work throughout 2012. http://ucalgary.ca/turing http://facebook.com/TuringYYC Next and Final Event: *** Turing and Intelligent Machines *** Nicole Wyatt Assistant Professor of Philosophy University of Calgary Tuesday, December 4, 4-5:30 pm, ICT 121 http://ucalgary.ca/turing/node/32 Turing's interest in the possibility of machine intelligence is probably most familiar in the form of the 'Turing Test', a version of which has been instantiated since 1991 as the Loebner Prize in Artificial Intelligence. To this date the Loebner Gold Medal has not been won. But should any future winner of the prize count themselves as having created a computer that thinks? Turing's 1950 Mind paper 'Computing Machinery and Intelligence', gives a sustained defence of the claim that a machine able to pass the test, which Turing called the Imitation Game, would indeed qualify as thinking. This lecture will explain the Turing Test as well as Turing's more general views concerning the prospects for artificial intelligence and examine both the criticisms of the test and Turing's rebuttals. Poster: http://ucalgary.ca/turing/node/35 http://ucalgary.ca/turing/files/turing/aty2012wyatt.pdf *** Watch previous lectures in this series on Mathtube *** http://mathtube.org/conference/lecture_video/Alan%20Turing%20Year Listen to the CJSW Presents feature on Alan Turing: http://cjsw.com/program/cjsw-presents/alan-turing-episode-1/ http://cjsw.com/program/cjsw-presents/turing-episode-2/ From jdgall84 at gmail.com Sun Dec 2 14:55:22 2012 From: jdgall84 at gmail.com (Jonathan Gallagher) Date: Sun Dec 2 14:55:43 2012 Subject: [Alta-Logic] peripatetic seminar Message-ID: Skipped content of type multipart/alternative-------------- next part -------------- A non-text attachment was scrubbed... Name: PeripateticFlyer.pdf Type: application/pdf Size: 71470 bytes Desc: not available Url : http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20121202/61d8f132/PeripateticFlyer.pdf From jdgall84 at gmail.com Mon Dec 10 01:57:23 2012 From: jdgall84 at gmail.com (Jonathan Gallagher) Date: Mon Dec 10 01:57:43 2012 Subject: [Alta-Logic] peripatetic seminar Message-ID: Skipped content of type multipart/alternative-------------- next part -------------- A non-text attachment was scrubbed... Name: PeripateticFlyer.pdf Type: application/pdf Size: 268414 bytes Desc: not available Url : http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20121210/e057394d/PeripateticFlyer.pdf From jdgall84 at gmail.com Fri Dec 14 19:32:55 2012 From: jdgall84 at gmail.com (Jonathan Gallagher) Date: Fri Dec 14 19:33:16 2012 Subject: [Alta-Logic] peripatetic seminar Message-ID: Skipped content of type multipart/alternative-------------- next part -------------- A non-text attachment was scrubbed... Name: PeripateticFlyer.pdf Type: application/pdf Size: 268414 bytes Desc: not available Url : http://mailman.ucalgary.ca/pipermail/alta-logic-l/attachments/20121214/a9d3e502/PeripateticFlyer.pdf