October 2025 - Categories - categories.org.au

Lecture notes by Bill Lawvere
by Michael Barr, Prof. 22 Apr '26

22 Apr '26

I got a request from someone named C. Muster who is searching for a set of lecture notes by Bill that he gave at U. Laval in 1974. Does anyone have a copy that they would be willing to send to him. Michael You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.as…> | Leave group<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.as…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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Subject: Dedicated to R. H. Street’s 80
by George Janelidze 16 Mar '26

16 Mar '26

Dear Colleagues, In honor of the 80th birthday of Professor Ross Howard Street, we are pleased to announce a special issue of Journal of Pure and Applied Algebra dedicated to celebrating his remarkable contributions to category theory and mathematics in general. Topics of interest include (but are not limited to) all areas of pure and applied category theory. The Guest Editors are: Jiří Adámek Maria Manuel Clementino Marino Gran George Janelidze Stephen Lack We are sending this message now so that you can begin to plan for possible submissions. The deadline will be 31 July 2026, and we will write again with further information about submissions once the journal’s website is ready. George Janelidze, on behalf of the Guest Editors Disclaimer - University of Cape Town This email is subject to UCT policies and email disclaimer published on our website at https://www.uct.ac.za/main/email-disclaimer or obtainable from +27 21 650 9111. If this email is not related to the business of UCT, it is sent by the sender in an individual capacity. Please report security incidents or abuse via https://csirt.uct.ac.za/report-incident You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.as…> | Leave group<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.as…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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7th Workshop on Formal Topology (7WFTop)-( first annoucement)
by Maria Emilia Maietti 11 Feb '26

11 Feb '26

================================== 7th Workshop on Formal Topology (7WFTop). >From topology to dynamic constructivism, and back. (first announcement) > ------------------------------ The 7th Workshop on Formal Topology will take place in Venice, Italy, on April 13-17, 2026 at Convento di San Francesco della Vigna. This is the seventh of a series of successful meetings on the development of Formal Topology and its connections with related approaches. The first six have been held in Padua (1997), Venice (2002), Padua (2007), Ljubljana (2012), Stockholm (2015), and Birmingham (2019). The meeting is supported by Dipartimento di Matematica “Tullio Levi-Civita” (Università di Padova). ------------------------------ Dynamic constructivism is a new approach to the foundation of mathematics proposed by Giovanni Sambin starting from the 90s and whose forthcoming book is a first organic exposition. The main claim is that mathematics is the result of a dynamic, human process, which stems from the interplay between the construction of mathematical entities, by abstraction and by idealization, and their selection according to their effectiveness in applications to reality and in the organization of mathematics itself. Pointfree topology in the form of Formal Topology and the more recent Positive Topology provides a key tool to link the effective content of mathematics with its ideal one, and thus achieve a synthesis of computation and visual intuition. A careful management of information within a dynamic view "back and forth" from mathematics to its foundation inevitably leads to accepting a plural vision of mathematics, thus enlightening connections between different constructive or even classical approaches to it. INVITED SPEAKERS: Steve Awodey, Andrej Bauer, Ingo Blechschmidt, Francesco Ciraulo, Maria Manuel Clementino, Thierry Coquand, Laura Crosilla, Tom de Jong, Martín Escardó, Hugo Herbelin, Hajime Ishihara, Tatsuji Kawai, Ansten Klev, Takako Nemoto, Michael Rathjen, Giovanni Sambin, Göran Sundholm, Mark van Atten, Steve Vickers, David Wärn, Joshua Wrigley. CONTRIBUTED TALKS There will be room for some contributed talks. Information about abstract submission will appear soon in the website of the workshop. ACCOMODATION The organizers will be happy to help you find accommodation, given the peculiarities of the city of Venice, and are making agreements with some facilities to guarantee partecipants a convenient price for their stay. If you are interested, please write to the workshop email address 7wftop(a)math.unipd.it<mailto:7wftop@math.unipd.it> as soon as possible, indicating "accommodation" in the subject. Finding accommodation at a reasonable price will be difficult or virtually impossible after June-July 2025. REGISTRATION The registration form will be available soon on the workshop website https://events.math.unipd.it/7wftop/. Participation will require a registration fee. SCIENTIFIC COMMITTEE Ingo Blechschmidt (University of Antwerp) Thierry Coquand (Gothenburg University) Martín Escardó (University of Birmingham) Maria Emilia Maietti (University of Padua) Per Martin-Löf (Stockholm University) ORGANIZING COMMITTEE Cipriano Junior Cioffo (University of Pisa) Francesco Ciraulo (University of Padua) Maria Emilia Maietti (University of Padua) Samuele Maschio (University of Padua) Pietro Sabelli (Czech Academy of Science) Giovanni Sambin (University of Padua) CONTACTS For inquiries, please send an e-mail to: 7wftop(a)math.unipd.it<mailto:7wftop@math.unipd.it> You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.as…> | Leave group<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.as…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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Lex objects in a 2-category
by Steven Vickers 01 Nov '25

01 Nov '25

An nLab page https://ncatlab.org/nlab/show/cartesian+object defines an object of X of a 2-category K to be “cartesian” iff the 1-cell X -> 1 and the diagonal X -> X^2 both have right adjoints. This assumes K has finite 2-products. If, further, K has finite PIE-limits, hence finite powers (cotensors) X^C, then it seems reasonable to define X to be “lex” if every diagonal X -> X^C has a right adjoint. Unless I’ve made a mistake, in the 2-category of categories this characterises the lex categories. Have these lex objects in a 2-category been studied? Steve Vickers. You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Leave group<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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Academic positions at the University of Bath, UK
by Guy McCusker 31 Oct '25

31 Oct '25

Though the below advertisement is not explicitly asking for category theorists, we would welcome applications from anyone with an interest in developing theoretical aspects of cybersecurity, which could certainly include people on this mailing list. I hope this will not be considered spam! Please circulate to anyone you think might be interested. All the best, Guy. — The Department of Computer Science at the University of Bath is seeking to appoint two lecturers in cybersecurity, who will join the Mathematical Foundations of Computation group: https://www.bath.ac.uk/research-groups/mathematical-foundations-of-computat… We’re particularly looking for individuals with research interests around fundamental aspects of cybersecurity, including but not limited to - post-quantum cryptography - formal methods and verification - complexity, logical systems and type theory. The official job announcements and online application form can be found here: https://www.bath.ac.uk/jobs/Vacancy.aspx?ref=AP13145 *Important dates* Application deadline: 10 December 2025 Interviews to be held on: 26-27 January and 2-3 February 2026 For any questions about the post or the recruitment process, please contact James Davenport (masjhd AT bath.ac.uk) or Thomas Powell (trjp20 AT bath.ac.uk). You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Leave group<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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*** 6th ItaCa Workshop *** ** Second Announcement **
by Giuseppe Metere 28 Oct '25

28 Oct '25

*** 6th ItaCa Workshop *** ** Second Announcement ** https://progetto-itaca.github.io/ItaCa-25/ Dear colleagues and friends, the 6th ItaCa Workshop will take place in Milano, Italy, on December 22–23, 2025. The program will start on the morning of December 22 and continue throughout the morning of December 23, at the Settore Didattico di via Mangiagalli of the Università degli Studi di Milano. The ItaCa Workshops form part of a continuing series of focused scientific meetings organized by ItaCa, the Italian community of category theorists. The aim of these workshops is to promote interaction, collaboration, and dissemination of recent research in category theory and its applications. The workshops are intended as an opportunity to strengthen the Italian categorical community while fostering dialogue with the broader international network. Particular emphasis is placed on the participation of students and early-career researchers, who are especially encouraged to contribute short talks and to take advantage of the opportunity to engage with senior researchers in an open and collaborative atmosphere. The meeting will be held in person, offering ample opportunity for scientific discussion and informal interaction. Participation is free of charge, but registration is required. To register, please fill in the following form: https://forms.gle/ySwnNUU6ymPkzdCt8 Participants wishing to give a contributed talk are kindly requested to send a short abstract (PDF format) to luca.reggio(a)unimi.it<mailto:luca.reggio@unimi.it> and gabriele.lobbia(a)unimi.it<mailto:gabriele.lobbia@unimi.it> Please notice that the deadline for talk submission is approaching! A limited amount of financial support is available for PhD students and postdoctoral researchers who do not have access to funding from their home institutions. Those interested are kindly invited to contact one of the organizers. Finally, participants are advised to book their accommodation as soon as possible, as hotel availability in Milan tends to be limited during that period of the year. Deadlines: Talk submission: November 18. Acceptance notification: November 25. Registration: December, 8. Programme Committee Ivan Di Liberti (chair, Göteborgs universitet) Gabriele Lobbia (Università di Milano) Luca Reggio (Università di Milano) Martina Rovelli (UMass Amherst) Pawel Sobocinski (Tallinn University of Technology) Enrico M. Vitale (UCLouvain) Joshua L. Wrigley (Université Paris Cité) Organising Committee Francesco Dagnino (Università di Genova) Gabriele Lobbia (Università di Milano) Giuseppe Metere (chair, Università di Milano) Andrea Montoli (Università di Milano) Fabio Pasquali (Università di Milano) Luca Reggio (Università di Milano) Vito Volpe (Università di Milano) .ƸӜƷ.•°*”˜˜”*°•.ƸӜƷ.•°*”˜˜”*°•.ƸӜƷ. Giuseppe Metere, PhD Professore Associato DeFENS Università degli Studi di Milano *** Il tuo 5x1000 al diritto allo studio Università degli Studi di Milano CF 80012650158 You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Leave group<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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PhD studentship in logic and information at UCL
by Pym, David 28 Oct '25

28 Oct '25

Applications are invited for a PhD studentship at UCL with project title 'A Foundational Theory of Information Based on Inference’. The joint supervisors are Tim Button and David Pym. UK and international candidates can be considered. Application deadline: 13:00 UK time on Monday 05 January 2026. Note that two references must also be submitted by this time. Description: Information is one of the most widely-used concepts of our times. But it has not yet been given convincing logical or mathematical foundations. Without them, we lack adequate reasoning tools for understanding the complex ecosystems of systems, including AI systems, upon which the society depends. This project will rectify this by developing an inferentialist semantic theory of information. There are three key components: CONCEPTUAL ANALYSIS. The project begins with a philosophically precise account of the concepts required for an inferentialist account of information (there is at present no such inferentialist account in the literature). Dretske expressed the key concepts of information in terms of intentionality, truth, and transmissibility (in ‘Metaphysics of Information’); we crucially replace truth with inferability, and trace the consequences of this replacement. LOGIC. Proof-theoretic semantics (P-tS) provides a mathematical-logical realization of inferentialist reasoning. The project will develop a P-tS for the logical theory of information, capturing the conceptual analysis developed in (1) by developing the mathematical-logical theory of an inferentialist primitive unit of information, the ‘inferon’. This proof-theoretic approach will counterpoint the model-theoretic view of information articulated in ‘situation theory’ (as developed by Barwise, Seligman, Devlin, and others). SYSTEMS. The P-tS tools developed in (2) will provide the basis for a mathematical account of distributed systems modelling — a key tool from computer science for understanding the organization of information processing systems. This will yield a reasoning-based theory of information flow in models of distributed systems. This PhD project will be supervised jointly by Professor Tim Button (UCL Philosophy) and Professor David Pym (UCL Computer Science and Institute of Philosophy, University of London). Applicants should hold or be about to obtain a strong Master-level degree in philosophy, mathematics, or computer science, and have a strong background and interest in logic. Project details: https://ucl-epsrc-dtp.github.io/2026-27-project-catalogue/projects/2531bd16… Studentship details and application process: https://www.ucl.ac.uk/epsrc-doctoral-training/prospective-students/ucl-epsr… Contacts: Tim Button (tim.button(a)ucl.ac.uk, https://www.homepages.ucl.ac.uk/~uctytbu/) David Pym (david.pym(a)sas.ac.uk, www.cantab.net/users/david.pym/) You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Leave group<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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Applied Category Theory 2026: First Call for Papers
by Priyaa Varshinee Srinivasan 27 Oct '25

27 Oct '25

------------------------------------------------------------------------ Call for Papers 9th Annual International Conference on Applied Category Theory (ACT2026) July 6 - July 10, 2026 Tallinn, Estonia https://actconf2026.github.io ------------------------------------------------------------------------ The 9th International Conference on Applied Category Theory will take place at the Estonian Maritime Academy of Tallinn University of Technology, Tallinn, Estonia from 6 - 10 July. The conference will be preceded by the Adjoint School Research Week from June 29 - July 3, 2026. This conference follows previous events at Florida (2025), Oxford (2023), Maryland (2023), Strathclyde (2022), Cambridge (2021), MIT (2020), Oxford (2019) and Leiden (2018). Applied category theory is important to a growing community of researchers who study computer science, logic, engineering, physics, biology, chemistry, social science, systems, linguistics and other subjects using category-theoretic tools. The background and experience of our members is as varied as the systems being studied. The goal of the Applied Category Theory conference series is to bring researchers together, strengthen the applied category theory community, disseminate the latest results, and facilitate further development of the field. SUBMISSIONS We accept submissions in English in the following three tracks: 1. Research 2. Software demonstrations 3. Teaching and communication Detailed Call for Papers is available at https://actconf2026.github.io/cfp.html Extended abstracts and conference papers should be prepared with LaTeX. For conference papers please use the EPTCS style files available at >. The submission link is https://easychair.org/my/conference?conf=act2026. Reviewing is single-blind, and we are not making public the reviews, reviewer names, the discussions nor the list of under-review submissions. This is the same as previous instances of ACT. IMPORTANT DATES The following dates are all in 2026, and Anywhere On Earth. - Abstracts Due : Wednesday 23 March - Full papers Due : Friday 30 March - Authors notification : 11 May - Adjoint school research week: 29 June - 3 July - Camera-ready version due : TBA - Conference begins : 6 July ORGANIZING COMMITTEE Geoff Cruttwell, Mt. Allison University, Canada (PC co-Chair) Paweł Sobociński, Tallinn University of Technology (General Chair) Priyaa Varshinee Srinivasan, Tallinn University of Technology (Organizing co-Chair, PC co-Chair) Kristi Ainen, Tallinn University of Technology (Organizing co-Chair) Sofiya Taskova, Tallinn University of Technology (Sponsorship Chair) STEERING COMMITTEE John Baez, University of California, Riverside & University of Edinburgh, U.K. Bob Coecke, University of Oxford, U.K. Michael Johnson, MacQuarie University Simona Paoli, University of Aberdeen, U.K. Dorette Pronk, Dalhousie University, Canada. David Spivak, Topos Institute, U.S.A. PROGRAM COMMITTEE Alexis Toumi, Planting Space Bryce Clarke, Tallinn University of Technology Barbara König, University of Duisburg-Essen Bojana Femic, Serbian Academy of Sciences and Arts Chris Heunen, The University of Edinburgh Daniel Cicala, Southern Connecticut State University Dusko Pavlovic, University of Hawaii Evan Patterson, Topos Institute Fosco Loregian, Tallinn University of Technology Gabriele Lobbia, Università di Bologna Georgios Bakirtzis, Institut Polytechnique de Paris Jade Master, University of Strathclyde James Fairbanks, University of Florida Jonathan Gallagher, Hummingbird Biosciences Joe Moeller, Caltech Jules Hedges, University of Strathclyde Julie Bergner, University of Virginia Kohei Kishida, University of Illinois, Urbana-Champaign Maria Manuel Clementino, CMUC, Universidade de Coimbra Mario Román, University of Oxford Marti Karvonen, University College London Martina Rovelli, UMass Amherst Masahito Hasegawa, Kyoto University Matteo Capucci, University of Strathclyde Michael Shulman, University of San Diego Nick Gurski, Case Western Reserve University Niels Voorneveld, Cybernetica Paolo Perrone, University of Oxford Peter Selinger, Dalhousie University Paul Wilson, University of Southampton Robin Cockett, University of Calgary Robin Piedeleu, University College London Rory Lucyshyn-Wright, Brandon University Rose Kudzman-Blais, University of Ottawa Ryan Wisnesky, Conexus AI Sam Staton, University of Oxford Shin-Ya Katsumata, Kyoto Sangyo University Simon Willerton, University of Sheffield Spencer Breiner, National Institute of Standards and Technology Tai Danae Bradley, SandboxAQ Titouan Carette, École polytechnique Tom Leinster, The University of Edinburgh Walter Tholen, York University Teaching & Communication Selma Dündar-Coecke, University College London, Institute of Education Ted Theodosopoulos, Nueva School We look forward to your participation in the conference! Thank you, PC Chairs (Geoff & Priyaa) You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Leave group<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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Vacancy in "Algebra and combinatorics" at the Université Libre de Bruxelles
by VERCRUYSSE Joost 27 Oct '25

27 Oct '25

(Sorry for double postings) Dear colleagues, My university Université Libre de Bruxelles (Brussels, Belgium) is announcing a vacancy for a permanent possition in “Algebra and combinatorics”. Please feel free to forward this announcement to anyone who might be interested. More information (e.g about formal requirements and teaching load) is in the official vacancy announcmeent to which your can find a link below. Candidates can contact me directly if they have any questions, here are already some first remarks: . The vacancy is open for eligible candidates working in any subfield of algebra or any subfield of combinatorics (so there is no need to work in both fields !). . There is a probational period of 3 years before the position becomes permanent, however there is no selection proceedure after 3 years, only a check if the candidate satisfies all requirements after 3 years, the most important one is being able to teach in French at the end of this period (an extension of the probation period could be negociated if there are exceptional circumstances). . The hiring is at the level of “Chargé de cours”, which is the first of 3 levels of permanent positions in our system (the two next levels being “professeur” and “professeur ordinaire”). . The announcement tells that it is “subject to the approval by the academic board of 24th November 2025”. This is purely formal decision; to give the candidates maximal time to prepare their file (deadline for submissions being 31 January 2026), the vacancy is already made public now. . The teaching load as mentioned in the announcement is not definitive yet (and depends for example on the fact whether the candidate can start teaching in French from the start of the contract). In particular, the candidate can propose a different subject for the Master course in the teaching load. Links to the vancancy pages: https://cwfront.ulb.ac.be/vacacad/vacancies/download/10158 https://www.ulb.be/fr/vacances-d-emplois-academiques-et-scientifiques/facul… Best wishes, Joost You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Leave group<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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Workshop for Martín Escardó's 60th, Birmingham, 17-18 Dec
by Tom de Jong 24 Oct '25

24 Oct '25

Dear all, In celebration of Martín Escardó's 60th birthday this year, we are pleased to announce a two-day workshop on *17–18 December 2025* at the *University of Birmingham*. https://tdejong.com/mhe60 The full list of over 20 invited speakers can be found on the website and reflects Martín's diverse contributions to constructive mathematics, domain theory, locale theory, logic, topology and homotopy/univalent type theory. The workshop is co-located with the Midlands Graduate School (MGS) Christmas Seminar on 16 December 2025 and will support remote participation. If you would like to attend (in person or remotely), please register by *21 November 2025* by completing this form: https://forms.cloud.microsoft/e/4GgaZHTxad We hope to see many of you there, Tom de Jong (tom.dejong(a)nottingham.ac.uk) Eric Finster (e.l.finster(a)bham.ac.uk) You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Leave group<https://outlook.office365.com/groups/groupsubscription?source=EscalatedMess…> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>

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