June 2014 - Categories - categories.org.au

Partial functor
by David Leduc 17 Mar '15

17 Mar '15

Hi, A partial functor from C to D is given by a subcategory S of C and a functor from S to D. What is the appropriate notion of natural transformation between partial functors that would allow to turn small categories, partial functors and those "natural transformations" into a bicategory? The difficulty is that two partial functors from C to D might not have the same definition domain. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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PhD opportunities at the University of Birmingham
by Paul Levy 01 Jul '14

01 Jul '14

* Imminent funding deadline - please contact us immediately if you are interested. * Dear all, We invite applications for PhD study at the University of Birmingham. We are a group of (mostly) theoretical computer scientists who explore fundamental concepts in computation and programming language semantics. This often involves profound and surprising connections between different areas of computer science and mathematics. From category theory to lambda-calculus and computational effects, from topology to constructive mathematics, from game semantics to program compilation, this is a diverse field of research that continues to provide new insight and underlying structure. See our webpage, with links to individual researchers, here: http://www.cs.bham.ac.uk/research/groupings/theory/ Information about PhD applications may be found here: http://www.cs.bham.ac.uk/admissions/postgraduate-research/ If you are considering applying, please contact any of us. We will be very happy to discuss the opportunities available. Best regards, The Birmingham CS theory group -- Martin Escardo (topology, computation with infinite objects, constructive mathematics, intuitionistic type theory) Dan Ghica (game semantics, heterogeneous computing, model checking) Achim Jung (mathematical structures in the foundations of computing: logic, topology, order) Neel Krishnaswami (type theory, verification, substructural logic, interactive computation) Paul Levy (denotational semantics, lambda-calculus with effects, nondeterminism, category theory, game semantics) Uday Reddy (semantics of state, separation logic) Eike Ritter (security protocol verification) Hayo Thielecke (abstract machines, concurrent and functional programming, software security) Steve Vickers (constructive mathematics and topology, category theory and toposes) -- Paul Blain Levy School of Computer Science, University of Birmingham +44 121 414 4792 http://www.cs.bham.ac.uk/~pbl -- Paul Blain Levy School of Computer Science, University of Birmingham +44 121 414 4792 http://www.cs.bham.ac.uk/~pbl [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Helmut Roehrl
by Bodo Pareigis 30 Jun '14

30 Jun '14

I am sorry to inform you that after long illness Helmut Roehrl of UCSD died on January 30, 2014. An obituary (in German) can be found in mathe-lmu.de under Zeitschrift, Download-Archiv, Nr. 29. Bodo Pareigis [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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CSL-LICS 2014 (online registration closes on June 30)
by Andrzej Murawski 29 Jun '14

29 Jun '14

CALL FOR PARTICIPATION JOINT MEETING OF the Twenty-Third EACSL Annual Conference on COMPUTER SCIENCE LOGIC (CSL) AND the Twenty-Ninth Annual ACM/IEEE Symposium on LOGIC IN COMPUTER SCIENCE (LICS) July 14-18, 2014, Vienna, Austria http://vsl2014.at/csl-lics/ http://lii.rwth-aachen.de/lics/csl-lics14/ Online Registration Deadline: Monday 30th June 2014 http://vsl2014.at/registration/ CSL is the annual meeting of the European Association for Computer Science Logic (EACSL) intended for computer scientists whose research activities involve logic, as well as for logicians working on issues significant for computer science. LICS is an annual international forum on theoretical and practical topics in computer science that relate to logic. The organizers of these two series of meetings have chosen to join the 2014 editions of these meetings into a single event within the Federated Logic Conference (FLoC) that will be part of the Vienna Summer of Logic 2014. Thus, in 2014, these meetings have one program committee, one program, and one proceedings. INVITED SPEAKERS Christel Baier (TU Dresden) Patrick Cousot (ENS Paris and NYU) INVITED TUTORIAL SPEAKERS Assia Mahboubi (INRIA Saclay) Jasmin Fisher (MSR Cambridge) PROGRAM http://www.easychair.org/smart-program/VSL2014/CSLLICS-program.html AFFILIATED WORKSHOPS Workshop Block 1 (July 12-13) CL&C 5th International Workshop on Classical Logic and Computation DCM 10th Int'l Workshop on Developments in Computational Models DTP Dependently-Typed Programming GSB Workshop on Gentzen Systems and Beyond 3 LCC Workshop on Logic and Comptuational Complexity LINEARITY 3rd International Workshop on Linearity LOLA 5th Workshop on Syntax and Semantics of Low-Level Languages LSB 5th International Workshop on Logic and Systems Biology PC FLoC Workshop on Proof Complexity SD 3rd Workshop on Structures and Deduction Workshop Block 2 (July 17-18) AISS Algorithmics of Infinite State Systems 2014 APPA All about Proofs, Proofs for All CICLOPS-WLPE Int'l Joint Workshop on Implementation of Constraint and Logic Programming Systems and Logic-based Methods in Programming Environments 2014 FCS-FCC Joint Workshop on Foundations of Computer Security and Formal and Computational Cryptography HOPA Higher Order Program Analysis LFMTP 9th International Workshop on Logical Frameworks and Meta-languages: Theory and Practice NLCS 2nd Workshop on Natural Language and Computer Science PCCR 2nd Workshop on the Parameterized Complexity of Computational Reasoning PSC Proof, Structure and Computation AWARDS The Kleene Award for Best Student Paper will be given for the best student paper(s), as judged by the program committee. The EACSL Outstanding Dissertation Award, named for Wilhelm F. Ackermann, will be presented during the joint meeting. The LICS Test-of-Time Award 2014 will be presented during the joint meeting. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Jim Lambeck and photos of CT 2013
by Koslowski 28 Jun '14

28 Jun '14

I was lucky enough to meet Jim in person a few times, e.g. at the famous Octoberfests and CT 1991 in Montreal during my time in the US. And I've seen him giving very nice talks at a rather advanced age. I was, and still am, deeply impressed by the man and the mathematician. On a more positive note: some pictures from CT 2013 in Sydney are finally available (just in time for CT 2014): http://www.iti.cs.tu-bs.de/TI-INFO/koslowj/PHOTOS/CT-2013/ http://www.iti.cs.tu-bs.de/TI-INFO/koslowj/PHOTOS/CT13/ The names will be added at a later stage, though. -- J?rgen Koslowski [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Intro to higher order categorical logic question
by Vasili I. Galchin 27 Jun '14

27 Jun '14

Hello, In the "Introduction to Part II" paragraph one , two type theories are mentioned. The last sentence of this paragraph states "These two versions are shown to be equivalent, although the second(equality .. my words) is useful for describing the internal language of a topos". Question: In what sense are these two type theory equivalent? In some technical sense? Kind regards, Vasya [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Jim Lambeck
by John Duskin 27 Jun '14

27 Jun '14

I knew Jim since I was a graduate student at McMaster in the 60ties. More recently, I was fascinated to find out that Jim was interested in mathematical physics in his early days and had done fundamental work in it. I had intended to write him about it but now it’s too late. My loss!! We will miss him !! [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Jim Lambek
by Michael Barr 27 Jun '14

27 Jun '14

I regret to inform you all that Jim died this afternoon. His son says it was congestive heart failure which is as good a way as any to describe dying of old age. He was still coming to seminar last fall and celebrated his 91st birthday in December in pretty good shape, but has been gradually going downhill since. I don't believe he came to the office since late fall. He had a good run. Michael [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Professorship Available
by Neil Ghani 22 Jun '14

22 Jun '14

Dear All We are looking for a new professor and Head of Department at Strathclyde. People on the categories list might be interested as there is a significant amount of category theory done here so you sou;ld find a fertile soil to put down roots. Details can be found at www.jobs.ac.uk/job/AIZ356/head-of-department/ If you are at all interested, even vaguely, then please do drop me a line. Always happy to chat …. All the best Neil [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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local compactness in four kinds of topology
by Paul Taylor 15 Jun '14

15 Jun '14

Local Compactness and Bases in various formulations of Topology www.paultaylor.eu/ASD/loccbv I would like to ask a specialist question before telling you about this draft paper. In the theory of continuous lattices there is a result due to Jimmie Lawson that says that, if a<<b but not a<<c then there is a Scott-open filter that contains b but not c. The idea is to iterate the interpolation property: a<<...<<b2<<b1<<b0=b. Of course this requires Dependent Choice. Does anyone have an example of a topos without Dependent Choice containing a locale without enough Scott-open filters like this? ----------------- I have posted a longer version of this announcement on "Constructive News", addressed to Formal Topologists: https://groups.google.com/forum/#!topic/constructivenews/i1YWESQPh0Y A basis for a locally compact space is given by a family of pairs of subspaces, one open and the other compact. This paper gives the complete axiomatisation of the relation on indices that says when a basic compact subspace is covered by a finite set of basic open ones. It is a completely rewritten version of one I circulated last year called "A Concise Presentation for Locally Compact Spaces" and in particular now also characterises continuous functions. This work (already in last year's version) is innovative in that the axiomatisation does not require the basis to be closed under finite unions and intersections, as had been done in previous work by Achim Jung and Philipp Sunderhauf and by me. Therefore the leading example of a basis - balls in a metric space - is included. This step shows a lot of the features of interval analysis, but generalised from R to locally compact spaces. An equivalence of categories is proved in Point-Set Topology, Locale Theory, Formal Topology and Abstract Stone Duality. It turns out that, even though one can describe the points, open sets and basic compact sets explicitly, in order to prove correctness in the classical case it is necessary to go via Locales and Formal Topology. Doing this in all four formulations of general topology and their associated logical foundations provides a setting in which to examine how they differ in logical strength. We can say precisely that a continuous function according to a particular definition is a certain relation between sets that are definable in the corresponding logical system. Paul Taylor [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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