October 2021 - Categories - categories.org.au

Re: "First" use of 'Category theory' to describe our field
by David Roberts 24 Feb '24

24 Feb '24

Dear Ross, no, that's pretty good! It's mildly surprising that it took ~20 years for the name to 'stick', but maybe less so given that the field grew slowly to start. Thanks, David David Roberts Webpage: https://ncatlab.org/nlab/show/David+Roberts Blog: https://thehighergeometer.wordpress.com On Thu, 11 Jul 2019 at 08:21, Ross Street <ross.street(a)mq.edu.au> wrote: > > Dear David > > From memory, the Pure Mathematics Honours (USyd) course that Max Kelly taught in 1965 > was called ``Category Theory''. It concentrated on different kinds of morphisms > and factorizations in a category, and finished with adjoint functors. > Also John Gray's (UIllinois) 1968-69 graduate course had that name. > > From Eilenberg I heard that each person using categories should have their own category of expertise. > I told this to John Gray who said that was fine; the time had come for that category to be Cat. > > I would suggest that the first category theorists to think of themselves as such were Eilenberg's students at Columbia. > However, Mac Lane was definitely a category theorist. > > This is probably not the verifiable stuff you were seeking. > > Ross > > > On 10 Jul 2019, at 10:01 PM, David Roberts <droberts.65537(a)gmail.com> wrote: > > Hi all, > > the (idle) question is: when did the phrase 'category theory' catch on > for the field? Clearly it didn't leap from either of the heads of > Eilenberg or Mac Lane full-grown, since they used the phrase 'General > theory of natural equivalences'. There are the old 'Reports of the > Midwest Category Seminar' lecture notes (the first in 1967), which > hints that 'category theory' wasn't quite the name in use. > > Even more interesting: who was the first "category theorist", by that name? > > Answers referring to verifiable sources would be best. > > Thoughts? > > David > > > > David Roberts > Webpage: https://ncatlab.org/nlab/show/David+Roberts > Blog: https://thehighergeometer.wordpress.com > [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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AMS-MRC Applied Category Theory 2022
by Valeria de Paiva 30 Oct '21

30 Oct '21

dear all, Just announcing our MRC on "Applied Category Theory", May 20--June 4th 2022, at Beaver Hollow Conference Center, NY. Deadline for applications is 15 Feb 2022. Mentors/organizers are John Baez, Simon Cho, Daniel Cicala, Nina Otter and myself. Please let your students, post-docs and friends in general know! Full details can be found at https://www.ams.org/programs/research-communities/2022MRC-Categories Best regards and Happy Halloween! Valeria -- Valeria de Paiva http://vcvpaiva.github.io/ https://topos.institute/ http://www.cs.bham.ac.uk/~vdp/ [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Pursuing Stacks
by David Roberts 27 Oct '21

27 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. Mateo Carmona has made (with the collaboration of Ulrik Buchholtz) an extended and revised version of: Pursuing stacks https://github.com/thescrivener/PursuingStacks Originally written between February 1983 and January 1984 represents a very important moment in the development of Grothendieck, namely that of "le nouveau style". You can see it here: https://agrothendieck.github.io/divers/ps.pdf Relevant to this work is also a note written in 1968 called "Tapis de Quillen" https://agrothendieck.github.io/divers/tapisQscan.pdf (and a project of transcription https://agrothendieck.github.io/divers/tapisQ.pdf) Remarks, and corrections, in general, are welcome. If you want to see more, please visit and get involved in https://agrothendieck.github.io/ David Roberts Webpage: https://ncatlab.org/nlab/show/David+Roberts Blog: https://thehighergeometer.wordpress.com [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Publication of Volume LXII-4 of the Cahiers
by Andrée Ehresmann 21 Oct '21

21 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. Dear colleagues, We are pleased to inform you that Volume LXII-4 (4th quarter 2021) of the Cahiers is now freely downloadable from the website of the Cahiers: <http://cahierstgdc.com/> <http://cahierstgdc.com/> http://cahierstgdc.com/ <http://cahierstgdc.com/> both as a whole issue and as separate articles. Best regards, Andree Ehresmann, Marino Gran and Rene Guitart [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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TACL 2022: First announcement
by TACL2022 21 Oct '21

21 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. =================================================== TOPOLOGY, ALGEBRA AND CATEGORIES IN LOGIC (TACL 2022) First announcement =================================================== Conference: June 20-24, 2022 in Coimbra School: June 13-18, 2022 in Praia de Mira https://www.mat.uc.pt/~tacl2022 Organized by the Centre for Mathematics (CMUC <https://cmuc.mat.uc.pt/rdonweb/>) and the Department of Mathematics (DMUC <https://www.uc.pt/fctuc/dmat>) of the University of Coimbra Scope -------- Studying logic via semantics is a well-established and very active branch of mathematical logic with many applications in computer science and elsewhere. The area is characterized by results, tools and techniques stemming from various fields, including universal algebra, topology, category theory, order, and model theory. The programme of the conference TACL 2022 will focus on three interconnecting mathematical themes central to the semantic study of logic and their applications: topological, algebraic, and categorical methods. TACL 2022 is the tenth conference in the series Topology, Algebra and Categories in Logic (TACL, formerly TANCL). Earlier instalments of this conference have been organized in Tbilisi (2003), Barcelona (2005), Oxford (2007), Amsterdam (2009), Marseille (2011), Nashville (2013), Ischia (2015), Prague (2017), and Nice (2019). Featured topics --------------------- Contributed talks are intended to be about topological, algebraic or categorical methods used in mathematical or computer science logic. This includes, but is not limited to, the following areas: * Algebraic logic * Algebraic structures in CS * Categorical methods in logic * Coalgebra * Domain theory * Fuzzy and many-valued logics * Lattice theory * Lattices with operators * Modal logics * Non-classical logics * Ordered algebraic structures * Ordered topological spaces * Pointfree topology * Proofs and types * Residuated structures * Semantics * Stone-type dualities * Substructural logics * Topological semantics of modal logic Invited speakers --------------------- * Marta Bilkova, Czech Academy of Sciences, Prague * David Fernandez-Duque, Ghent University * Richard Garner, Macquarie University, Sydney * Jean Goubault-Larrecq, Ecole Normale Superieure Paris-Saclay * Peter Johnstone, University of Cambridge * Vincenzo Marra, University of Milan * Amanda Vidal, Artificial Intelligence Research Institute, Barcelona * Friedrich Wehrung, University of Caen * Fan Yang, University of Helsinki Lecturers at the Summer School ------------------------------------------ * Dirk Hofmann, University of Aveiro * Rosalie Iemhoff, Utrecht University * Graham Manuell, University of Coimbra * Walter Tholen, York University, Toronto Submission instructions ------------------------------- Authors can submit an Extended Abstract of 2 pages (including references) at the EasyChair conference system: https://easychair.org/conferences/?conf=tacl2022 Important dates --------------------- School: June 13-18, 2022 Conference: June 20-24, 2022 Contributed talks: Submission deadline: March 4, 2022 Notification to authors: April 15, 2022 The school's programme will start on Tuesday June 14 in the morning and will end on Saturday June 18 in the afternoon. A bus transfer from and to Coimbra will be arranged by the organisers, on the afternoon of June 13 and June 18, respectively. The conference programme will start on Monday June 20 in the morning and will end on Friday June 24 in the afternoon. Financial support ----------------------- For the summer school a certain amount of funding is available for those in financial need. This is intended primarily for students, but non-students can be considered in exceptional circumstances. Program Committee --------------------------- Peter Jipsen, Chapman University, USA (PC co-chair) Jorge Picado, Universidade de Coimbra, Portugal (PC co-chair) Nick Bezhanishvili, University of Amsterdam, Netherlands Agata Ciabattoni, Vienna University of Technology, Austria Maria Manuel Clementino, Universidade de Coimbra, Portugal Mai Gehrke, Universit?? C??te D'Azur, Nice, France Silvio Ghilardi, Universit?? degli Studi di Milano, Italy Zuzana Hanikova, Inst. of Computer Science, Czech Academy of Sciences John Harding, New Mexico State University, USA Tomas Jakl, University of Cambridge, UK Zurab Janelidze, Stellenbosch University, South Africa Ramon Jansana, Universitat de Barcelona, Spain Agi Kurucz, King's College London, UK Serafina Lapenta, Universita degli Studi di Salerno, Italy Matias Menni, Conicet and Universidade Nacional de La Plata, Argentina George Metcalfe, University of Bern, Switzerland Hiroakira Ono, Japan Advanced Institute of Science & Technology, Japan Daniela Petrisan, University Paris Diderot (Paris 7), France Adam Prenosil, Universita degli Studi di Cagliari, Italy Luca Reggio, University of Oxford, UK Greg Restall, University of St Andrews, UK Benno van den Berg, University of Amsterdam, Netherlands Steering Committee --------------------------- Guram Bezhanishvili, New Mexico State University, United States Mai Gehrke, CNRS and Universite Cote d'Azur, France Silvio Ghilardi, University of Milan, Italy Ramon Jansana, University of Barcelona, Spain Hilary Priestley, University of Oxford, United Kingdom James Raftery, University of Pretoria, South Africa Yde Venema, University of Amsterdam, Netherlands Organizing Committee ----------------------------- Maria Manuel Clementino (chair) Igor Arrieta Ana Belen Avilez Celia Borlido Maria Joao Ferreira Carlos Fitas Goncalo Gutierres Dirk Hofmann Graham Manuell Jorge Picado Sandra Pinto Rui Prezado Manuela Sobral Lurdes Sousa More Information ------------------------ Information about registration as well as suggested hotels will be forthcoming in future announcements. If you would like to receive future announcements, please send a message to this effect to the conference e-mail address. TACL 2022 web site: https://www.mat.uc.pt/~tacl2022/ Conference email: tacl2022(a)mat.uc.pt School web site: https://www.mat.uc.pt/~tacl2022/#school [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Research Fellows in Logic at UCL, London
by David Pym 20 Oct '21

20 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. Please note, with my apologies, an error in the information below: the closing date should read 31 October. Thank you to the many people who have pointed this out. [Apologies for cross-postings. Please share widely. Thank you.] I am looking for Research Fellows in Logic to join me in UCL’s PPLV group (http://pplv.cs.ucl.ac.uk/welcome/) in London. I’m interested in the following topics: - Foundational work in classical, intuitionistic, modal, and substructural logic, with a particular interests in - proof-theoretic semantics, including primary and categorical approaches, and - foundational work in reductive logic and proof-search. - Applications of logical ideas to systems modelling. - The development of logical tools for systems modelling, including dynamic, epistemic, deontic, and doxastic approaches, with case studies in security and policy modelling. Posts are 12 months in the first instance with possible extensions subject to agreement. The posts are funded by UK EPSRC grants. Please note that the closing date is 15 October. Details, including salary, terms, and how to apply may be found at UCL’s jobs page: https://atsv7.wcn.co.uk/search_engine/jobs.cgi under Research Fellow/Senior Research Fellows in Logic, specifically https://atsv7.wcn.co.uk/search_engine/jobs.cgi?SID=amNvZGU9MTg3OTAwMiZ2dF90… For an informal discussion, please contact me at - d.pym(a)ucl.ac.uk - http://www.cs.ucl.ac.uk/staff/D.Pym/ Thank you, David [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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TYPES 2021 post-proceedings: Open call for papers
by Henning Basold 20 Oct '21

20 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. Open call for papers for the Post-proceedings of the 27th International Conference on Types for Proofs and Programs TYPES 2021 TYPES is a major forum for the presentation of research on all aspects of type theory and its applications. TYPES 2021 was held 14-18 June 2021 virtually hosted by University Leiden, Netherlands. The post-proceedings volume will be published in LIPIcs, Leibniz International Proceedings in Informatics, an open-access series of conference proceedings (http://www.dagstuhl.de/en/publications/lipics) Submission to this post-proceedings volume is open to everyone, also to those who did not participate in the conference. We welcome high-quality descriptions of original work, as well as position papers, overview papers, and system descriptions. Submissions should be written in English, not overlapping with published or simultaneously submitted work to a journal or a conference with archival proceedings. The scope of the post-proceedings is the same as the scope of the conference: the theory and practice of type theory. In particular, we welcome submissions on the following topics: * Foundations of type theory and constructive mathematics; * Applications of type theory (e.g., linguistics or concurrency); * Dependently typed programming; * Industrial uses of type theory technology; * Meta-theoretic studies of type systems; * Proof assistants and proof technology; * Automation in computer-assisted reasoning; * Links between type theory and functional programming; * Formalising mathematics using type theory; * Homotopy type theory and univalent mathematics. IMPORTANT DATES * Abstract submission: 19 November 2021 (AoE) * Paper submission: 26 November 2021 (AoE) * Author notification: 25 March 2022 DETAILS * Papers have to be formatted with the current LIPIcs style and adhere to the style requirements of LIPIcs: http://www.dagstuhl.de/en/publications/lipics/instructions-for-authors/ * The upper limit for the length of submissions is 20 pages, excluding title page and bibliography but including appendices. * The processing charge will kindly be sponsored by LIACS (Leiden Institute for Advanced Computer Science) for up to 20 publications, given that these publications do not exceed the page limit. See here for details about the processing charge: https://submission.dagstuhl.de/documentation/faq/11 * Papers have to be submitted as PDF through EasyChair: https://easychair.org/conferences/?conf=posttypes2021 * Authors have the option to attach to their submission a zip or tgz file containing code (formalised proofs or programs), but reviewers are not obliged to take the attachments into account and they will not be published. * In case of questions, e.g. on the page limit, contact one editors either directly or through <types21(a)liacs.leidenuniv.nl>. EDITORS - Henning Basold (https://liacs.leidenuniv.nl/~basoldh/) Leiden University, NL - Jesper Cockx (https://jesper.sikanda.be/) Technical University Delft, NL - Silvia Ghilezan (http://imft.ftn.uns.ac.rs/~silvia/) University of Novi Sad, RS [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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composite qualities (extensive x intensive)
by Posina Venkata Rayudu 19 Oct '21

19 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. Dear All, I hope and pray that you and your families are all well. If I may, space, according to Kant, is the form of intuition, i.e. the canonical extensive quality of intuition. Along similar lines, time, according to Proust, is the shape of memory, i.e. the canonical extensive quality of memory. Now, given a category of objects, we can find out its qualities. For example, the category of irreflexive graphs satisfies one of the axioms of cohesion (see F. William Lawvere, 2007, Axiomatic Cohesion; http://www.tac.mta.ca/tac/volumes/19/3/19-03.pdf) which is: subobject classifier is 1 piece (see Lawvere and Schanuel, Conceptual Mathematics, p. 345), but doesn't satisfy another cohesion axiom: pieces of product equals the product of pieces of the factors (p(A x A) = 3, while p(A) x p(A) = 1 x 1 = 1, where A = * ---> *, one of the two basic shapes of the category of irreflexive graphs). However, reflexive graphs, wherein arrows have distinguished loops as sources and targets, satisfy the product preservation of the pieces functor (for illustration see Fig. 6 in https://zenodo.org/record/4048096#.YW4e2RpBzIU) Simply put, given a category, we can see if it is cohesive; its qualities: both extensive and intensive qualities. Now, according to Poincaré (see p. 45 in F. William Lawvere, Axiomatic Cohesion; http://www.tac.mta.ca/tac/volumes/19/3/19-03.pdf) Extensive E and intensive I qualities jointly reflect isomorphisms. For example, with (E1 x I1) and (E2 x I2) as products of the canonical extensive AND intensive qualities of two cohesive objects C1 and C2, respectively, if composite quality E1 x I1 is isomorphic to E2 x I2, then the cohesive object C1 is isomorphic to C2 (see pp. 173-174 in Lawvere and Schanuel's Conceptual Mathematics). In light of the above, I was wondering if we can characterize the nature of a category whose extensive quality is space and/or that of a category whose extensive quality is time. Isn't it a problem of knowing only one of the two variables of a 2-variable function (e.g. instead of a surface on a plane we have a curve). Independent of Kant and Proust, isn't it mathematically interesting to know if the calculation of qualities of a category can be inverted (not necessarily isomorphisms, but, say, inverse images or fibers of a map from the category C of categories to a product category E x I of extensive and intensive quality types)? Returning to Poincaré, is the product category (E x I) of categories of extensive (E) and intensive (I) quality types coadequate for the category C of categories? Now, given a functor C ---> E x I we get a pair of functors C ---> E AND C ---> I by aft composition with corresponding projections to factor categories E and I. With extensive quality E = S (category of spaces/modes of cohesion), we get to know how the codomain intensive qualities I structure the domain category C of categories. Similarly, with extensive quality E = T (category of time(s?)/types of change), we get to know how intensive qualities structure the category of categories. These calculations can then be brought to bear on the nature of and relations between intuition and memory (since they have space and time as their respective extensive qualities; for worked out examples of cohesive categories (reflexive graphs) and quality types (idempotents), see: https://zenodo.org/record/3924474) I look forward to your corrections of any mistakes I might have made in my description of extensive and intensive qualities. Thanking you, posina [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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postdoctoral position on polynomial functors at Topos Institute
by David Spivak 19 Oct '21

19 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. Dear all, I'm happy to announce that Topos Institute is hiring a postdoctoral research fellow to study polynomial functors and their applications. A mathjobs listing is here: https://www.mathjobs.org/jobs/list/18637 and information on the precise project can be found here: http://www.dspivak.net/grants/AFOSR2020-Topos-Supplement2021.pdf Applicants should be strong in mathematics or computer science and know category theory. Strong programming experience or strong math research experience is required, and a combination of the two is preferred. The position is for 1 year, but a renewal may be possible, depending on funding. Topos is committed to building a team with diverse perspectives and life experiences, so those with underrepresented personal or professional backgrounds are highly encouraged to apply. Unfortunately, Topos is unable to sponsor visas for international candidates at this time. We are looking to hire as soon as possible. Please feel free to contact me if you have any questions. Best regards, David [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Conant Prize for Andrej Bauer
by Jirí Adámek 16 Oct '21

16 Oct '21

CAUTION: The Sender of this email is not from within Dalhousie. Andrej has recieved the 2022 Conant Prize for the best expository article. Details can be found here: https://www.ams.org/news?news_id=6827&utm_source=Informz&utm_medium=email&u tm_campaign=Informz%20Mailing&_zs=NG0BH1&_zl=en4T6 [www.ams.org] Congratulations Andrej! Best wishes Jiri [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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