May 2022 - 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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Pieter Hofstra
by Philip Scott 01 Jun '22

01 Jun '22

It is with great sadness that we announce that our dear friend and colleague Pieter Hofstra (1975-2022) passed away unexpectedly on May 1. Pieter obtained his PhD from Utrecht University, under Jaap van Oosten, studying realizability toposes. His research interests included general topos theory, realizability, inverse semigroups and groupoids, abstract computability, and homotopy type theory. Among his recent works, with J. Funk he introduced the notion of isotropy groups of toposes, which he was actively developing with students and colleagues. While Pieter was a brilliant researcher, a kind teacher and a caring supervisor, we will most remember him as a friend. When we have any details for a memorial service, we will pass them along. Richard Blute, Simon Henry, Philip Scott (University of Ottawa) [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Conference in Almeria
by Noson＠sci.brooklyn.cuny.edu 27 May '22

27 May '22

I would like to draw your attention to the conference “Functor Categories, Model Theory, and Constructive Category Theory”, to be held July 11-15, 2022 at the University of Almería, Spain. For more information please visit https://web.northeastern.edu/martsinkovsky/p/Conferences/Almeria2022/FM.html [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Announcement of Higher structures and homotopical algebra Session at the AMS Sectional Meeting this fall
by Martina Rovelli 26 May '22

26 May '22

To all enthusiasts for higher structures and homotopical algebra, We are organizing a special session at the AMS Sectional Meeting at the University of Massachusetts in Amherst, MA. The dates of this meeting are October 1-2, 2022 (Saturday-Sunday), and we expect it to occur in-person. We would be delighted if you participated, and please feel free to encourage others to attend as well. Information about this meeting can be found at http://www.ams.org/meetings/sectional/sectional.html Special sessions follow some AMS policies that may not resemble other conferences you?ve attended, so bear in mind the following: 1) The AMS does not pay any expenses of faculty attending special sessions. However, PhD students are encouraged to apply for travel funding from AMS; see http://www.ams.org/student-travel for more information, including application procedures and deadlines. 2) Everyone who attends the meeting is required to pay a registration fee. Over the years there have been a significant proportion of meeting participants who have not done so, resulting in a considerable loss of revenue to the AMS. For information about the cost of registering, child care, or special needs, see https://www.ams.org/meetings/sectional/2301_other.html Best, John Berman, Michael Ching, Ivan Contreras Palacios, Owen Gwilliam, and Martina Rovelli [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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In search of papers on monads and algebraic theories
by Nathanael Arkor 25 May '22

25 May '22

Dear all, I have been searching for several papers/preprints regarding monads, and algebraic theories, without much success. If anyone has a copy of one of the following papers, or knows where to find a copy, I would be very grateful to hear from you. (Unfortunately I do not have much information further than the title, author, and year, since I have come across these simply as citations.) - "A note on a construction of Kleisli" (Michael Barr, University of Illinois, 1965). - "J-adjonctions et J-monades" (Yves Diers, Universit?? de Lille, 1970). - "Relative Functorial Semantics, III: Triples vs. Theories" (Fred Linton, Banach Center (Warsaw), 1974). - "Clones, Cotriples and the Structure Semantics adjointness" (George Reynolds, Union College, 1975), the abstract for which can be found here: https://www.ams.org/journals/notices/197601/197601FullIssue.pdf. If anyone knows whether there was ever a "Relative Functorial Semantics, II" (the first in the series presumably being the 1969 paper "Relative functorial semantics: adjointness results"), I would also like to know. In addition, Fred Linton apparently gave two talks about algebraic theories a number of years after his papers on the subject. If anyone attended either of the following talks (presuming the talks were given) and recalls any of the content, I would be interested to hear. - "Triples vs. Theories???one last time" at Billfest, 1997. - "Triples vs. Theories as Yet another Yoneda Lemma" at either Octoberfest 2005 or StreetFest 2005. Many thanks, Nathanael [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Second ANTIPODE workshop
by SARACCO Paolo 21 May '22

21 May '22

Dear Colleague, We are glad to announce the "second ANTIPODE workshop" that will be held at the ULB - Université Libre de Bruxelles on the 12th and 13th of September, 2022. This two-days event aims at being an occasion to gather together international experts and young researchers in the theory of partial actions and representations as well as in related topics such as inverse semigroups, groupoids, Hecke algebras. Please, feel free to share the details of this event in your local academic community. ================================================================= REGISTRATION Registration is now open via a Google Form on the webpage https://hopfalgb.ulb.be/ANTIPODE2. You may also reach it directly via the following link: https://forms.gle/FrqefvoJZNPMx1Bj7 Please, register before the 1st of August at 23:59:59 Anywhere on Earth. Due to the limited budget at our disposal, we can offer limited financial support to (young) participants who will actively contribute to the event. If you are interested to apply, please mention it in the registration form. We will contact you once we collected all the applications. ================================================================= CONFIRMED SPEAKERS - Alessandro D’Andrea (Rome) - Ganna Kudryavtseva (Ljubljana) - Martina Lanini (Rome) - Johan Öinert (Karlskrona) - Juan Jacobo Simón Pinero (Murcia) ================================================================= ORGANISERS Michele D'Adderio Paolo Saracco Joost Vercruysse For any additional information, please contact us at Paolo.Saracco(a)ulb.be, Michele.DAdderio(a)ulb.be, Joost.Vercruysse(a)ulb.be. -- Paolo Saracco, PhD (he/him) ULB - Université Libre de Bruxelles Département de Mathématique Campus de la Plaine CP 216 Bd du Triomphe sites.google.com/view/paolo-saracco homepages.ulb.ac.be/~psaracco -- - Le mie parole sono incise nelle montagne - - My words are carved into the mountains - [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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TYPES 2022 -- Second call for participation
by Pierre-Marie Pédrot 20 May '22

20 May '22

SECOND CALL FOR PARTICIPATION 28th International Conference on Types for Proofs and Programs, TYPES 2022 and EuroProofNet Cost Action CA20111 meeting Nantes, France, 20-25 June 2022 https://types22.inria.fr Early registration deadline: **June, 1st 2022** Registration: https://types22.sciencesconf.org/registration/ Registration fees: see below INVITED SPEAKERS Youyou Cong: Composing Music from Types Ekaterina Komendantskaya: Refine and Synthesise: a type-theoretic view on neural network robustness. Sam Lindley: On the expressive power of types. Leonardo de Moura: The Lean 4 theorem prover and programming language PROGRAMME https://types22.inria.fr/programme/ REGISTRATION FEES To facilitate their attendance, TYPES'22 offers a reduced rate for students, available in the registration form. In addition, all registrations performed before June, 1st will be offered a discount. It is possible to register for the satellite events only, which will take place on June 24th and 25th. Such a registration is free, but mandatory for catering purposes. Registering to TYPES'22 implicitly includes registration to satellite events. See the registration page https://types22.sciencesconf.org/registration/ for details. BACKGROUND The TYPES meetings are a forum to present new and on-going work in all aspects of type theory and its applications, especially in formalised and computer assisted reasoning and computer programming. The TYPES areas of interest include, but are not limited to: * foundations of type theory and constructive mathematics; * applications of type theory; * 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; * formalizing mathematics using type theory. The EuroProofNet Cost Action CA20111 focuses on the same research topics as TYPES and partially sponsors the TYPES Conference. CONTACT Email: types2022(a)easychair.org PROGRAM COMMITTEE Sandra Alves (University of Porto) Carlo Angiuli (Carnegie Mellon University) Stephanie Balzer (Carnegie Mellon University) Lars Birkedal (Aarhus University) Frédéric Blanqui (INRIA) Sandrine Blazy (Université de Rennes 1 - IRISA) Thierry Coquand (University of Technology) Andrej Dudenhefner (Saarland University) Jacques Garrigue (Nagoya University) Delia Kesner (Université de Paris) (PC Co-Chair) Marina Lenisa (Università di Udine) Paul Blain Levy (University of Birmingham) Sara Negri (Università degli Studi di Genova) Pierre-Marie Pédrot (INRIA) (PC Co-Chair) Luca Padovani (Università di Torino) Zoe Paraskevopoulou (Northeastern University) Brigitte Pientka (McGill University) Matija Pretnar (University of Ljubljana) Talia Ringer (University of Washington) Kathrin Stark (Princeton University) Paweł Urzyczyn (University of Warsaw) Lionel Vaux (Université d’Aix-Marseille) Niki Vazou (IMDEA Software) TYPES STEERING COMMITTEE Andreas Abel (Gothenburg University) Sandra Alves (University of Porto) (Secretary) Henning Basold (Leiden University) (SC chair) Frédéric Blanqui (INRIA) Ugo de'Liguoro (Università di Torino) Matthieu Sozeau (INRIA & Université de Nantes) ORGANIZERS Assia Mahboubi (INRIA & Université de Nantes) Matthieu Sozeau (INRIA & Université de Nantes) Nicolas Tabareau (INRIA & Université de Nantes) [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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CCC2022 -September 19-23, 2022- call for contributions
by Maria Emilia Maietti 18 May '22

18 May '22

CALL FOR?? CONTRIBUTIONS: CCC 2022: Continuity, Computability, Constructivity ??? From Logic to Algorithms Department of Mathematics and???? ONLINE Padova, Italy, September 19-23, 2022 Conference website?????? https://events.math.unipd.it/ccc2022/ ============================================== Submission link https://easychair.org/conferences/?conf=ccc20220 Submission deadline: ???? August 16, 2022 Nofication of acceptance: ?? August 26, 2022 ==================================================== Topics: constructive mathematics constructive analysis computable analysis exact real number computation CCC is a workshop series that brings together researchers applying logical methods to the development of algorithms, with a particular focus on computation with infinite data, where issues of continuity, computability and constructivity play major roles. Specific topics include exact real number computation, computable analysis, effective descriptive set theory, constructive analysis and topology, and related areas. The overall aim is to apply logical methods in these disciplines to provide a sound foundation for obtaining exact and provably correct algorithms for computations with real numbers and other continuous data, which are of increasing importance in safety-critical applications and scientific computation. Participation is welcome in person or online. Previous workshops have been held in Cologne 2009, Trier 2012, Gregynog 2013, Ljubljana 2014, Kochel 2015, Nancy 2017, Faro 2018, Ljubljana 2019, Faro 2020 (online), Birmingham 2021 (online). ===================================================================== Submission Guidelines The workshop invites all contributions relating to computation where issues of continuity, computability and constructivity play major roles. Specific areas of interest include: ?????? Exact real number computation ?????? Correctness of algorithms on infinite data ?????? Computable analysis ?????? Complexity of real numbers, real-valued functions, etc. ?????? Effective descriptive set theory ?????? Domain theory ?????? Constructive analysis and topology ?????? Constructive foundations ?????? Category-theoretic approaches to computation on infinite data ?????? Weihrauch degrees ?????? Other related areas. Extended abstracts (1-2 pages) should be submitted in pdf format. A post-proceedings volume will be published in the open-access journal Logical Methods in Computer Science. =============================================== Tutorial speakers: ?????? Alexander Miquel (Universidad de La Republica, Uruguay) ?????? Linda Westrick (Penn State University, USA) Invited speakers: ?????? Miko??aj Boja??czyk (Warsaw, Poland) ?????? Tatsuji Kawai (JAIST, Japan) ?????? Michael Rathjen (Leeds, UK) ?????? Andreas Rauh (Oldenburg, Germany) ======================================================== Program Committee ?????? Pieter Collins (Maastricht, Netherlands) ?????? Achim Jung (Birmingham, UK) ?????? Maria Emilia Maietti (Padova, Italy)?? (chair) ?????? Arno Pauly (Swansea, UK) ?????? Alex Simpson (Ljubljana, Slovenia) ?????? Holger Thies (Kyoto, Japan) ?????? Chuangjie Xu (Munich, Germany) ?????? Ning Zhong (Cincinnati, USA) ?????? Martin Ziegler (KAIST, Republic of Korea) Organizing committee ?????? Francesco Ciraulo (Padova, Italy) ?????? Maria Emilia Maietti (Padova, Italy) ?????? Samuele Maschio (Padova, Italy) ?????? Pietro Sabelli (Padova, Italy) Contact All questions about submissions should be emailed to ccc22(a)math.unipd.it [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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ItaCa Fest - Coraglia and Kock - 19 May
by Ivan Di Liberti 16 May '22

16 May '22

Dear all, The next date of the ItaCa Fest will be May 19, 2022 at 3 pm (Italian time): - G. Coraglia, - J. Kock. The zoom link is the following: https://stockholmuniversity.zoom.us/j/68792232558 While the Fest website is this one: https://progetto-itaca.github.io/pages/fest22.html Join us (and bring a friend)! Cheers, Beppe, Ivan, Edoardo, Fosco, Paolo. ———————————————————————————————————— Coraglia. Title: Comonads for dependent types Abstract: In exploring the relation between a classical model of dependent types (comprehension categories) and a new one (judgemental dtts) we pin-point the comonadic behaviour of weakening and contraction. We describe three different 2-categories and show that they are 2-equivalent, then proceed to analyze the benefits of each of the three. The fact that one can precisely relate such different perspectives allows, for example, for a swift and cleaner treatment of type constructors: we show how certain categorical models for dependent types come inherently equipped with some due to the choices one makes in introducing tools to interpret context extension. Kock. Title: Decomposition spaces, right fibrations, and edgewise subdivision Abstract: Decomposition spaces are simplicial infinity-groupoids subject to an exactness condition weaker than the Segal condition. Where the Segal condition expresses composition, the weak condition expresses decomposition. The motivation for studying decomposition spaces is that they have incidence coalgebras and Möbius inversion. The most important class of simplicial maps for decomposition spaces are the CULF maps (standing for 'conservative' and 'unique-lifting-of-factorisation'), first studied by Lawvere; they induce coalgebra homomorphisms. The theorem I want to arrive at in the talk says that the infinity-category of (Rezk-complete) decomposition spaces and CULF maps is locally an infinity-topos. More precisely for each (Rezk-complete) decomposition space D, the slice infinity-category Decomp/D is equivalent to PrSh(Sd(D)), the infinity-topos of presheaves on the edgewise subdivision of D. Most of the talk will be spent on explaining preliminaries, though. This is joint work with Philip Hackney. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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special volume of TAC in honour of Marta Bunge
by Valeria de Paiva 14 May '22

14 May '22

Dear colleagues, It's a pleasure to announce that (together with other friends) we have decided to organize a special volume of TAC dedicated to Marta Bunge and her deep technical and conceptual work in Category Theory along the years. Here is our call for papers. Colleagues that would like to join us, but might have difficulties with the timeline proposed are encouraged to get in touch with one of the guest editors of the volume. Best regards to all, Valeria, Maria Manuel, and Jonathon ============== SPECIAL VOLUME of TAC IN HONOUR OF MARTA BUNGE ON CELEBRATION OF A LIFE WORK IN CATEGORY THEORY Marta Bunge, Emerita Professor from McGill University, is the doyenne and a role model for women in Category Theory. Some of her friends and colleagues thought that it was about time we celebrated her work and asked the Editorial Board of TAC for a special celebratory volume. We are happy to tell you that the volume is going ahead and TAC will dedicate a special volume to her as a celebration of a life's work in category theory. Authors are invited to submit their manuscripts in electronic form to Maria Manuel Clementino <mmc(a)mat.uc.pt> ( or Jonathon Funk or Valeria de Paiva), possibly suggesting one of the Guest Editors be assigned to their paper. All papers will be carefully refereed following the standards of "Theory and Applications of Categories". Prospective authors are requested to: 1. Copy the managing editor of TAC, Geoffrey Crutwell at (at tac(a)mta.ca) , when submitting an article. 2. As with ordinary TAC papers, for the final version, authors should follow the instructions on the TAC website and then send their final .tex and .pdf files to Geoff (again at tac(a)mta.ca) The guest editors would much prefer that also the initial submission of a PDF already use the TAC template to simplify the work of reviewing. The deadline for submission of papers is Nov 30th, 2022. The Guest Editors Maria Manuel Clementino, Valeria de Paiva and Jonathon Funk -- 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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