January 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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Postdoc opening in categorical semantics
by Patricia Johann 01 Feb '21

01 Feb '21

CAUTION: The Sender of this email is not from within Dalhousie. Dear Colleagues, I have an opening for a postdoc, as described in the ad below. In addition to accepting applications, I will be very happy to respond to informal enquiries about any aspect of the position, from technical ones to ones about life in a beautiful, "alternative" mountain town in western North Carolina. Best wishes, -patricia -------- Applications are invited for a postdoctoral researcher position in the Computer Science Department at Appalachian State University. The position is part of an NSF-funded project on the categorical semantics of advanced data types, such as nested types, GADTs, and other higher-kinded data types. The project aims to build on recent work on higher-kinded data types to understand the categorical settings in which they have initial algebra semantics. One primary goal is to classify such types according to the complexity of the categorical settings in which they have well-defined initial algebra semantics. Another is to understand what parametricity means, practically speaking, for them. The ideal applicant will have a strong background in functional programming, type theory, and category theory, although more expertise in one area may, together with a commitment to developing the required competencies, compensate for less in another. The successful applicant will also be excited about working on fundamental research questions on the themes of categorical semantics of data types and parametricity. Interests in applications and/or formalizing computer science theory in, e.g., Agda, are also welcome. The successful hire will work on the funded project with Prof. Patricia Johann at Appalachian State University, her students, and collaborating researchers. (Due to COVID-19, remote work may be possible for some initial portion of the position.) The duration of the position is initially one year, with guaranteed continuation by mutual agreement. The position will start at a mutually agreeable date, ideally on or around 1 July 2021. Compensation will be competitive and commensurate with experience. Interested persons should first contact Patricia Johann at johannp(a)appstate.edu, briefly outlining their academic background and research interests, and why they are interested in the position. A complete application will consist of a cover letter and CV, including contact information for three academic references. Complete applications should be made online at https://appstate.peopleadmin.com/postings/27464 Review of applications will begin on 15 February 2021 and continue until the position is filled. Appalachian State University is an Affirmative Action/Equal Opportunity Employer. The University does not discriminate in access to its educational programs and activities, or with respect to hiring or the terms and conditions of employment, on the basis of race, color, national origin, religion, sex, gender identity and expression, political affiliation, age, disability, veteran status, genetic information or sexual orientation. Individuals with disabilities may request accommodations in the application process by contacting Patricia Johann. Any offer of employment to a successful candidate will be conditioned upon the University's receipt of a satisfactory criminal background report. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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ETAPS Test of Time Award 2021, call for nominations
by Tarmo Uustalu 01 Feb '21

01 Feb '21

CAUTION: The Sender of this email is not from within Dalhousie. ETAPS Test of Time Award The ETAPS Test of Time Award recognizes outstanding papers published more than 10 years in the past in one of the constituent conferences of ETAPS. The Award recognises the impact of excellent research results that have been published at ETAPS. See https://www.etaps.org/about/test-of-time-award Nominations Nominations for the 2021 ETAPS Test of Time Award are solicited from the ETAPS community. A nomination should include the title and publication details of the nominated paper, explain the influence it has had since publication, and why it merits the award. It should be phrased in terms that are understandable by the members of the award committee and suitable for use in the award citation, and should be endorsed by at least 2 people other than the person submitting the nomination. Self-nominations are not allowed. Nominations should be sent by Monday 15 February to the chair of the award committee, Don Sannella <dts(a)inf.ed.ac.uk>. Award committee The 2021 award committee consists of Rance Cleaveland, Ugo Dal Lago, Marieke Huisman, Peter Ryan, Don Sannella (chair), Gabriele Taentzer and Peter Thiemann. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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YaMCATS category theory seminars on Zoom next Friday, 5 Feb
by Steve Vickers 30 Jan '21

30 Jan '21

CAUTION: The Sender of this email is not from within Dalhousie. YaMCATS is the Yorkshire and Midlands Category Theory Seminars https://www2.le.ac.uk/departments/mathematics/extranet/staff-material/staff… Our next meeting, virtual by Zoom, will be hosted by Nicola Gambino at Leeds University next Friday afternoon. Details and Zoom link below. Nicola Gambino Simona Paoli Steve Vickers YaMCATS - Friday 5th February - University of Leeds (via Zoom) All times are UK (GMT = UTC+00:00). 14:30-15:30 Martin Escardo (University of Birmingham), Equality of mathematical structures 15:30-16:30 Sina Hazratpour (University of Leeds), Kripke-Joyal semantics for dependent type theory 16:30-17:00 Break 17:00-18:00 John Baez, Structured versus decorated cospans Zoom links: Nicola Gambino is inviting you to a scheduled Zoom meeting. Topic: YaMCATS 23 Time: Feb 5, 2021 02:30 PM London Join Zoom Meeting https://universityofleeds.zoom.us/j/81042397132?pwd=RTg3MFV1TUt2YzJXZVZJSkh… Meeting ID: 810 4239 7132 Passcode: 683026 Abstracts Martin Escardo Title: Equality of mathematical structures Abstract. Two groups are regarded to be the same if they are isomorphic, two topological spaces are regarded to be the same if they are homeomorphic, two metric spaces are regarded to be the same if they are isometric, two categories are regarded to be the same if they are equivalent, etc. In Voevodsky's Univalent Foundations (HoTT/UF), the above become theorems: we can replace "are regarded to be the same” by "are the same". I will explain how this works. I will not assume previous knowledge of HoTT/UF or type theory. Sina Hazratpur (University of Leeds) Title: Kripke-Joyal semantics for dependent type theory Abstract. Every topos has an internal higher-order intuitionistic logic. The so-called Kripke–Joyal semantics of a topos gives an interpretation to formulas written in this language used to express ordinary mathematics in that topos. The Kripke–Joyal semantics is in fact a higher order generalization of the well-known Kripke semantic for intuitionistic propositional logic. In this talk I shall report on joint work with Steve Awodey and Nicola Gambino on extending the Kripke–Joyal semantics to dependent type theories, including homotopy type theory. John Baez (University of California at Riverside) Structured versus decorated cospans Abstract. One goal of applied category theory is to understand open systems: that is, systems that can interact with the external world. We compare two approaches to describing open systems as cospans equipped with extra data: structured and decorated cospans. Each approach provides a symmetric monoidal double category, and we prove that under certain conditions these symmetric monoidal double categories are equivalent. We illustrate these ideas with applications to dynamical systems and epidemiological modeling. This is joint work with Kenny Courser and Christina Vasilakopoulou. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Leicester Pure Maths crisis- petition
by simona.paoli＠virgilio.it 30 Jan '21

30 Jan '21

CAUTION: The Sender of this email is not from within Dalhousie. Dear All, There is a threat to pure mathematics research at Leicester and a petition here https://www.ipetitions.com/petition/mathematics-is-not-redundant which I encourage you to sign. The proposals represent an attack on pure mathematics research in general and a specific threat to the category theory research represented at Leicester and to the LMS funded Yorkshire and Midlands Category Theory network which has its main node at Leicester. Best wishes, Simona. ------------------------------------------------------------------------------------------------------------ Dr Simona Paoli Associate Professor School of Mathematics and Actuarial Science University of Leicester, UK [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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First Call for Nominations: Beth Outstanding Dissertation Prize (BODP) 2021
by Sadrzadeh, Mehrnoosh 29 Jan '21

29 Jan '21

CAUTION: The Sender of this email is not from within Dalhousie. First Call for Nominations: E. W. Beth Outstanding Dissertation Prize 2021 Since 2002, the Association for Logic, Language, and Information (FoLLI) has been awarding the annual E.W. Beth Dissertation Prize to outstanding Ph.D. dissertations in Logic, Language, and Information (http://www.folli.info/?page_id=74) with financial support of the E.W. Beth Foundation (https://www.knaw.nl/en/awards/funds/evert-willem-beth-stichting/evert-wille…) Nominations are now invited for the best dissertation in these areas resulting in a Ph.D. degree awarded in 2020. The deadline for nominations is the 15th of April 2021. Qualifications: - A Ph.D. dissertation on a topic concerning Logic, Language, or Information is eligible for the Beth Dissertation Prize 2021, if the degree was awarded between January 1st and December 31st, 2020. - There are no restrictions on the nationality, ethnicity, age, gender or employment status of the author of the nominated dissertation, nor on the university, academic department or scientific institution formally conferring the Ph.D. degree, nor on the language in which the dissertation has originally been written. - In accordance with the aim of the Beth Foundation to continue and extend the work of the Dutch logician Evert Willem Beth, nominations are invited of excellent dissertations on topics in the broad remit of ESSLLI, including current topics in philosophical and mathematical logic, computer science logic, philosophy of science, philosophy of language, history of logic, history of the philosophy of science and scientific philosophy in general, as well as the current theoretical and foundational developments in information and computation, language, and cognition. Dissertations with results more broadly impacting various research areas in their interdisciplinary investigations are especially solicited. - If a nominated dissertation has originally been written in a language other than English, its dossier should still contain the required 10 page English abstract, see below. If the committee decides that a nominated dissertation in a language other than English requires translation to English for proper evaluation, the committee can transfer its nomination to the competition in 2022. The English translation must in such cases be submitted before the deadline of the call for nominations in 2022. The committee may recommend the Beth Foundation to consider supporting such nominated dissertations for English translation, upon request by the author of the dissertation. The prize consists of: - a certificate - a donation of 3000 euros, provided by the E.W. Beth Foundation - an invitation to submit the dissertation, possibly after revision, for publication in FoLLI Publications on Logic, Language and Information (Springer). Only digital submissions are accepted, without exception. Hard copy submissions are not allowed. The following documents are to be submitted in the nomination dossier: - The original dissertation in pdf format (ps/doc/rtf etc. not acceptable). - A ten-page English abstract of the dissertation, presenting the main results of each chapter. - A letter of nomination from the dissertation supervisor, which concisely describes the scope and significance of the dissertation, stating when the degree was officially awarded and the members of the Ph.D. committee. Nominations should contain the address, phone and email details of the nominator. - Two additional letters of support, including at least one from a referee not affiliated with the academic institution that awarded the Ph.D. degree, nor otherwise related to the nominee (e.g. former teachers, supervisors, co-authors, publishers or relatives) or the dissertation. - Self-nominations are not possible. All pdf documents must be submitted electronically, as one zip file, via EasyChair by following the link https://easychair.org/conferences/?conf=bodp2021. In case of any problems or questions please contact the chair of the committee Mehrnoosh Sadrzadeh (m.sadrzadeh(a)ucl.ac.uk) The prize will be awarded by the chair of the FoLLI board at a ceremony during the 32nd ESSLLI summer school in Utrecht, August 2-13, 2021. Beth dissertation prize committee 2021: Samson Abramsky (University of Oxford) Maria Aloni (University of Amsterdam) Cleo Condoravdi(Stanford University) Robin Cooper (University of Gothenburg) Guy Emerson (University of Cambridge) Katrin Erk (University of Texas at Austin) Sujata Ghosh (ISI, Chennai) Davide Grossi (Universities of Groningen and Amsterdam) Christoph Haase (University of Oxford) Louise McNally (Universitat Pompeu Fabra Barcelona) Reinhard Muskens (University of Amsterdam) Mehrnoosh Sadrzadeh (University College London, chair) Mark Steedman (University of Edinburgh) Matthew Stone (Rutgers University) Jouko Vaananen (University of Helsinki and University of Amsterdam) FoLLI is committed to diversity and inclusion and we welcomes dissertations from all under-represented groups [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Topos Institute Colloquium series
by David Spivak 29 Jan '21

29 Jan '21

CAUTION: The Sender of this email is not from within Dalhousie. Dear categorists, I'm writing to announce a new series of talks, called the Topos Institute Colloquium. Topos Institute is a new, independent non-profit research institute working to shape technology for the public benefit by advancing sciences of connection and integration. Our core research focuses around applications of category theory, type theory, and related fields, including but going significantly beyond topos theory. We're based in Berkeley, California. The first few speakers in the colloquium series are: David Spivak Richard Garner Gunnar Carlsson Samson Abramsky John Baez Milly Maietti The talks will generally occur on Thursdays, though the time of day will fluctuate based on the timezone of the speaker. For the time being, talks will occur virtually on Zoom; they will generally be recorded and uploaded to YouTube. The schedule, along with titles and abstracts, can be found here: https://topos.site/seminars/ If you are interested in receiving announcements, please sign up by sending an email with subject line "subscribe" to tim(a)topos.institute. We hope to see you there! Best regards, David [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Seminar talk on the semantics of bisimilarity
by Harley D. Eades III 29 Jan '21

29 Jan '21

CAUTION: The Sender of this email is not from within Dalhousie. Hi, everyone. On Friday, Feb. 5, 2021 between 9am and 10am EST (2pm - 3pm UTC), Dr. Shin-ya Katsumata will be giving a presentation as part of the CS Colloquium Series at Augusta University. Presentation details can be found here: https://the-au-forml-lab.github.io/colloquium_talks/Katsumata.html Shin-ya will discuss his work on a purely categorical characterization of bisimilarity. It's going to be a great talk! These talks are open to the general public via Zoom. I'll also be living streaming it on Youtube. So if you are interested in attending the Zoom meeting please RSVP with me before the talk. Questions will be taken from those on Zoom and YouTube. If you care to watch via YouTube, please use the following link: https://youtu.be/8auEgwMvoOc Feel free to share this message with everyone you know. I hope all of you, your family and friends are doing well! Very best, Harley [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Re: Invitation: GReTA online seminar, January 29 at 15:00 CET
by Heckel, Reiko (Prof.) 28 Jan '21

28 Jan '21

CAUTION: The Sender of this email is not from within Dalhousie. FYI, the next instalment of our seminar this Friday Reiko On 25/01/2021, 08:44, "GReTA seminar organisers" <greta(a)irif.fr> wrote: Dear colleagues, It is our great pleasure to invite you to a seminar of the “GReTA - Graph Transformation Theory and Applications” series: Friday, January 29, 15:00 CET “Confluence of Graph Transformation”, L. Lambers and F. Orejas (abstract: see attached) Please refer to http://www.irif.fr/~greta<https://eur03.safelinks.protection.outlook.com/?url=http:%2F%2Fwww.irif.fr%…> for further information on how to register for this Zoom meeting, or alternatively on how to attend the meeting via a YouTube live stream! The GReTA seminar series aims to serve as a platform for the international graph rewriting community, to promote recent developments and trends in the field, and to permit a regular networking and interaction between members of this community. Seminars are scheduled twice a month (cf. https://www.irif.fr/~greta/#talks<https://eur03.safelinks.protection.outlook.com/?url=https:%2F%2Fwww.irif.fr…> for a list of upcoming events). With best regards, Nicolas Behr, Jean Krivine and Reiko Heckel (GReTA organisers) ___________________________________________________ Date and time: Friday, January 29, 15:00 CET Speaker: L. Lambers and F. Orejas Title: Confluence of Graph Transformation Abstract: Confluence has been studied for graph transformation since several decades now. Confluence analysis has been applied, for example, to determining uniqueness of model transformation results in model-driven engineering. It is strongly related to conflict analysis for graph transformation, i.e. detecting and inspecting all possible conflicts that may occur for a given set of graph transformation rules. The latter finds applications, for example, in software analysis and design. Both conflict and confluence analysis rely on the existence and further analysis of a finite and representative set of conflicts for a given set of graph transformation rules. Traditionally, the set of critical pairs has been shown to constitute such a set. It is representative in the sense that for each conflict a critical pair exists, representing the conflict in a minimal context, such that it can be extended injectively to this conflict (M-completeness). Recently, it has been shown that initial conflicts constitute a considerably reduced subset of critical pairs, being still representative in a slightly different way. In particular, for each conflict there exists a unique initial conflict that can be extended (possibly non-injectively) to the given conflict (completeness). Compared to the set of critical pairs, the smaller set of initial conflicts allows for more efficient conflict as well as confluence analysis. We continue by demonstrating that initial conflicts (critical pairs) are minimally complete (resp. minimally M-complete), and thus are both optimally reduced w.r.t. representing conflicts in a minimal context via general (resp. injective) extension morphisms. We proceed with showing that it is impossible to generalize this result to the case of rules with application conditions (equivalent to FOL on graphs). We therefore revert to a symbolic setting, where finiteness and minimal (M-)completeness can again be guaranteed. Finally, we describe important special cases (e.g. rules with negative application conditions), where we are able to obtain minimally complete (resp. M-complete) sets of conflicts in the concrete setting again. Zoom registration link: https://zoom.us/meeting/register/tJIrd-ihrzgqHdO7-bPkhQG92mDpzKdIBCHb<https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fzoom.us%2…> Link to YouTube live stream: https://youtu.be/Um90A_lk4ik<https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fyoutu.be%…> ___________________________________________________ [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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Bohemian L&P Café: Michael Makkai, Feb. 2
by Steve Awodey 28 Jan '21

28 Jan '21

CAUTION: The Sender of this email is not from within Dalhousie. Bohemian Logical & Philosophical Café Michael Makkai Notions of identity for and in higher dimensional categories. RESCHEDULED February 2 at 16.00 Prague time (GMT+1) The zoom link is on the webpage: https://bohemianlpc.github.io <https://bohemianlpc.github.io/> Makkai’s abstract is at this link: https://bohemianlpc.github.io/abstracts/Makkai.pdf <https://bohemianlpc.github.io/abstracts/Makkai.pdf> Regards, Steve [For admin and other information see: http://www.mta.ca/~cat-dist/ ]

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