January 2025 - Categories - categories.org.au

Lecture notes by Bill Lawvere
by Michael Barr, Prof. 23 Apr '26

23 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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Collection honouring Robert Paré for his 80th birthday
by Bryce James Clarke 13 Jun '25

13 Jun '25

We are pleased to announce a special collection in Applied Categorical Structures honouring our friend and colleague, Bob Paré, on the occasion of this 80th birthday. Throughout his career Bob (Professor Emeritus and Adjunct Professor at Dalhousie University) has made several lasting contributions to category theory, including notable research in a broad range of subjects, such as double categories, higher categories, indexed categories, toposes and accessible categories. This collection will bring together contributions which honour the lasting impact Bob has made, and is making, in the category theory community. Submissions will be open from 1 October 2024 until 30 June 2025 at this link: https://link.springer.com/collections/dijeibfdbh All submissions on topics which celebrate Bob's work are welcome, including double categories, higher categories, indexed categories, toposes and accessible categories. The collection will be edited by four guest editors: - Bryce Clarke (Tallinn University of Technology) - Marco Grandis (University of Genoa) - Dorette Pronk (Dalhousie University) - Christina Vasilakopoulou (National Technical University of Athens) The publication process for this collection in Applied Categorical Structures differs from the traditional model for a special volume. Articles are published within whichever issue is open at the time, and concurrently published in the collection available at the above link. This helps papers to be published quickly, without having to wait for a whole issue to be ready, while still allowing all papers in the collection to be available in a single place. The editors are happy to answer any questions, and we look forward to receiving your submissions. Best wishes, Bryce, Marco, Dorette, and Christina. 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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Special Volume of MSCS in honor of Marek Zawadowski
by Chris Kapulkin 17 Mar '25

17 Mar '25

Dear Colleagues, We are honored to announce a special volume of the journal Mathematical Structures in Computer Science celebrating the work of Marek Zawadowski. Marek Zawadowski (1960-2024) was a mathematician at the University of Warsaw. He received his Ph.D. from the Université de Montréal in 1989 under the supervision of Gonzalo Reyes with the dissertation “Théorie de la descente pour les prétopos.” He made fundamental contributions to category theory, logic, and linguistics. He passed away unexpectedly in February 2024. This special volume is a celebration of Marek Zawadowski’s work and welcomes submissions on a broad range of topics, including: categorical logic, higher category theory, and linguistics. The volume will be edited by four guest editors: Pierre-Louis Curien (Université Paris Cité and Inria) Justyna Grudzińska (University of Warsaw) Chris Kapulkin (University of Western Ontario) Karol Szumiło (University of Warsaw) To submit your paper to the special volume, please go to https://mc.manuscriptcentral.com/mscs After starting a new submission, you will be asked (as part of Step 1) whether your manuscript is a candidate for a Special Issue; you should select “Tribute to Marek Zawadowski.” The editors will be happy to answer any questions at marek.zawadowski.memorial(a)gmail.com The submission deadline is March 31, 2025. If you are planning to submit a paper but are worried about making the deadline, please contact the editors at your earliest convenience. Best wishes, Chris Kapulkin For the Guest Editors 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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41st British Colloquium for Theoretical Computer Science
by Alasdair Lambert 15 Feb '25

15 Feb '25

BCTCS 2025 -- Call for Contributed Talks BRITISH COLLOQUIUM FOR THEORETICAL COMPUTER SCIENCE 2025 University of Strathclyde 14–16 April 2025 https://msp.cis.strath.ac.uk/bctcs2025/ ABOUT THE BCTCS The BCTCS is an annual event for UK-based researchers in Theoretical Computer Science to present their research and discuss future directions. The meeting aims to provide an environment in which PhD students can gain experience in presenting their work, to broaden their outlook on the subject, and to benefit from contact with established researchers. The scope of the colloquium includes all aspects of Theoretical Computer Science, including Algorithms, Automata Theory, Complexity Theory, Concurrency, Education, Formal Methods, Languages, Logics, Semantics, and Types. CONTRIBUTED TALKS We invite 30 minute contributed talks on any topic in the scope of the colloquium. Presentations from research students and early career researchers are particularly encouraged. To propose a talk, please fill in the submission form: https://forms.office.com/e/1E8nuEU9hS The scope of "theoretical computer science" is intended to be interpreted broadly. In particular, this year we invite talk proposals which detail novel and innovative ways to teach theoretical content, as part of a track focused on theoretical computer science education. For all talks, please ensure that your talk is accessible to other students who may not be specialists in your research topic. We put no restrictions on the originality or publication status of submissions. There will be no formal proceedings, but the collection of the contributed abstracts will appear in the Bulletin of the EATCS ( https://eatcs.org/index.php/eatcs-bulletin ). INVITED SPEAKERS We will have the following invited speakers: * Elizabeth Polgreen (Edinburgh) * Nicolai Kraus (Nottingham) * Jess Enright (Glasgow) * Jakub Opršal (Birmingham) * Conor Mc Bride (Strathclyde) * Rob van Glabeek (Edinburgh) REGISTRATION We hope to open registrations in January 2025. The registration fees will be as follows: * Early registration (until 24 March): £45 * Late registration (until 7 April): £60 Further details are available at https://msp.cis.strath.ac.uk/bctcs2025/ 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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Workshop "Advances in Interactive and Quantitative Semantics", 26-28 mai 2025, CIRM
by Pierre Clairambault 31 Jan '25

31 Jan '25

We are delighted to announce the workshop "Advances in Interactive and Quantitative Semantics" which will take place on the 26-28th of May 2025 at the CIRM in Marseille, France -- at the doorstep of the Calanques national park. The workshop marks the end of the ANR grant "Dyverse". It aims, on the one hand, to publicize some of the results obtained in the course of the project, but also to gather the communities around interactive and quantitative semantics. More information on the scientific context can be found in the web page: https://conferences.cirm-math.fr/3518.html We would be happy to see you there! Registration ============ Registration is free, and covers accommodation and meals on site, from the dinner on the sunday 25th to the lunch on the 28th. Pre-registration is open on the web site: https://conferences.cirm-math.fr/3518.html Pre-registrations will be validated on a first come first served basis, up to the available budget and the available slots at CIRM. Other expenses (travel, etc) are not covered. Programme ========= There will be 9 invited talks, by the following speakers: Aurore Alcolei, Université Paris Est Creteil Marcelo Fiore, University of Cambridge Simon Forest, Aix-Marseille Université Jim Laird, University of Bath Paul-André Melliès, CNRS & Université Paris Cité Hugo Paquet, Inria & ENS Paris Glynn Winskel, Queen Mary University of London ... and more TBA. There will also be a few slots (6 30-min slots) for contributed talks. We invite authors of contributed talks to send their proposals (titles and abstracts) to the organizers: pierre.clairambault(a)cnrs.fr, lionel.vaux(a)univ-amu.fr Best, Pierre Clairambault et Lionel Vaux Auclair 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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Research Engineer (12-Month Contract) - Huawei Canada
by Jing Wang (A) 31 Jan '25

31 Jan '25

Dear All， Huawei Canada seeking 4 Research Engineers with strong Haskell skills for a 12-month contract role. If you have a passion for research and innovation, we would love to hear from you! Position Details: * Contract Duration: 12 months * Location: Onsite,Markham, Ontario, Canada * Number of Positions: 4 About the job: * Engage in research projects focused on neuro-symbolic systems (NSSs) that leverage symbolic AI and formal methods to enhance and refine LLM outputs, ensuring the generation of acceptable symbolic results * Implement innovative NSS designs and validate their intended properties * Collaborate on research publications to disseminate findings About the ideal candidate: * A Ph.D. in Computer Science, Software Engineering, Mathematics, or a related field, with a preference for candidates specializing in symbolic techniques, particularly in formal methods tools * Proven experience in developing symbolic computation tools, such as programming language tools, compilers, model checkers, theorem provers, or similar applications. Familiarity with functional programming languages, especially Haskell, is an asset * A solid understanding of programming language theory, logic, and symbolic verification is an asset * A strong interest in the integration of LLMs with symbolic tools * Knowledge of Category Theory is an asset1 How to Apply: If you are interested in applying for this position, please send your resume to jing.wang9(a)h-partners.com<mailto:jing.wang9@h-partners.com> We look forward to your applications! Best, Angel(Jing) Wang Senior Recruiter, Recruitment Huawei Technologies Canada Co., Ltd. 19 Allstate Parkway, 5st Floor Markham, Ontario Canada L3R 5B4 Email: jing.wang9(a)h-partners.com<mailto:jing.wang9@h-partners.com> Corporate: www.huawei.com/ca [cid:image001.png@01DB7266.55736C60] 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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Heyting Day 2025 — Intuitionism and computability: symposium in honour of Jaap van Oosten, 14 March, Amsterdam
by Tom de Jong 27 Jan '25

27 Jan '25

=========================================================== Heyting Day 2025 — Models of intuitionism and computability Symposium in honour of Jaap van Oosten =========================================================== *14 March 2025, Amsterdam* Time: 10:00 - 16:45 Location: KNAW Trippenhuis - Kloveniersburgwal 29, Amsterdam https://www.knaw.nl/en/heyting-day-2025 *Abstract* Can we imagine a world in which computability is built-in into the very fabric of reality? The answer is a resounding yes. However, it took us almost 40 years to get the first detailed picture of such a world. Our speakers will give you a scenic tour around worlds of computability. They will introduce the relevant concepts and discuss the many amazing properties of such worlds. The symposium marks the retirement of Jaap van Oosten and will be conducted in English. *Invited speakers* - Andy Pitts (University of Cambridge) - Andrej Bauer (University of Ljubljana) - Sebastiaan Terwijn (Radboud University) - Jaap van Oosten (Utrecht University) If you would like to attend, please sign up at https://www.knaw.nl/en/heyting-day-2025 *Organisers* - Benno van den Berg, b.vandenberg3(a)uva.nl (University of Amsterdam) - Tom de Jong, tom.dejong(a)nottingham.ac.uk (University of Nottingham) - Albert Visser, a.visser(a)uu.nl (Utrecht University) 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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On why addition of ultrafilters over N is not commutative
by Bertalan Pecsi 25 Jan '25

25 Jan '25

Hi, Towards an understanding of the phenomenon why taking ultrafilters carry over binary operations and associativity but not commutativity (in the sense that if S is a semigroup then it induces a semigroup structure on βS), first I succeeded to generalize this to all monads over Set - I guess it should be well known as well, but then realized that actually the unit of the monad is not required in the proof, so actually all 'semigroupads' (or 'semimonads') carries over semigroups. The unit of the monad is required exactly to carry over monoids. I played around with this idea, and could also come up with correspondent identities involving the Kleisli star in place of the binary monad operation. In particular, a magmad on a category C is just an endofunctor T:C->C and a nat.transformation μ:TT->T (without any further requirements). For example, a 'central element' of (T,μ) would be a nat.transf. ζ:1->T satisfying μ ζT = μ Tζ, and in this case any magma S with central element c, we'll have ζ(c) central in the induced magma TS. So, I basically found some answer to the question in the title: the ultrafilter monad itself is not commutative (whatever it should mean(?)) and therefore commutativity is not carried over. Does anyone know about these kinds of ideas appearing in the literature? Thanks in advance, Bertalan Pécsi 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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subobject as monomorphism
by Posina Venkata Rayudu 25 Jan '25

25 Jan '25

Dear Professor Michael Barr, I hope all is well. If I may, Grothendieck redefines subobject as: a subobject of A is not an object, but an object B, together with a monomorphism u: B --> A (https://www.math.mcgill.ca/barr/papers/gk.pdf, p. 2). Your time permitting, would you be kind enough to shed some light on Grothendieck's conceptual trajectory, along with whatever it is that might have made it indispensable, from the then subset is a set to his subset is a 1-1 function, a conceptual refinement, whose mathematical value was more than adequately explained in Professor F. William Lawvere's geometry of figures (Lawvere & Schanuel, Conceptual Mathematics, pp. 370-371, https://conceptualmathematics.wordpress.com/wp-content/uploads/2013/02/conc…) which can be traced all the way back to Cayley's representation, not to forget Yoneda embedding or Professor's F. William Lawvere's functorial semantics, along the way. If I am not mistaken, the above Tohoku paper you translated is the first instance of a subobject reincarnating as monomorphism. When viewed from the perspective of: a part of a whole is both itself and its relationship to the whole (Lawvere, Objective Logic, p. 53, https://zenodo.org/records/7059109) shouldn't Grothendieck's 'subobject is monomorphism' have been readily incorporated into math (without having to go through the trials and tribulations of having to fight against the accusations of circumlocution, etc.). I look forward to your corrections and clarifications! Thanking you, Yours truly, posina P.S. Rational passage between concepts (https://conceptualmathematics.wordpress.com/2023/02/17/rational-passage/) is my Year 2025 project :) So, I'd appreciate any pointers to go from one concept to another. I could be wrong, but broadly it seems, speaking of the passage between concepts (GRAPH, MONOID, FUNCTION, etc.), since concepts are objectified as categories (the theory of irreflexive directed graphs as a category consisting of two parallel maps, i.e., source, target: Arrows --> Dots), it seems a passage between concepts must necessarily be functorial (mapping of objects must be respectful of their mutual relations, composition, etc). 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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Proof Assistants Special Session @ North American ASL Meeting (May 15 & 16, 2025, Las Cruces, NM)
by Jonathan Weinberger 24 Jan '25

24 Jan '25

======================================== Call for Participation and Contributions North American ASL Meeting Special Session on Proof Assistants May 15 & 16, 2025 New Mexico State University, Las Cruces, NM ======================================== A Special Session on Proof Assistants will be held as part of the 2025 North American Annual Meeting of the Association for Symbolic Logic. The whole ASL meeting will take place May 13-16, while the special session on proof assistants will take place on the last two days May 15 & 16. The confirmed invited speakers are: Favonia (University of Minnesota) Leonardo de Moura (Amazon Web Services) Emily Riehl (Johns Hopkins University) Egbert Rijke (Johns Hopkins University) Mike Shulman (University of San Diego) General information about the meeting is at: https://math.nmsu.edu/asl-2025/index.html There is some limited capacity for contributed talks (duration approx. 20 minutes): The deadline for contributed talk submissions is Thursday, February 27, 2025. Abstracts should be sent to Jonathan Weinberger at jweinberger(a)chapman.edu<mailto:jweinberger@chapman.edu> and Patricia Johann at johannp(a)appstate.edu<mailto:johannp@appstate.edu>. Reviewing of abstracts will be lightweight. Abstracts must abide by the rules listed on this page: https://aslonline.org/rules-for-abstracts/ In particular, abstracts must use the template linked off of the above page. Note, however, that authors of abstracts submitted to the Special Session are NOT required to be ASL members. The deadline for student travel applications is February 13, 2025. Applications should be sent to Shannon Miller at asl(a)uconn.edu<mailto:asl@uconn.edu> and must abide by the rules listed on this page: https://aslonline.org/student-travel-awards/ 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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