One of the most lively series of conferences on applied category theory is ‘SYCO’: the Symposium on Compositional Structures. And the next one is coming soon!

• Symposium on Compositional Structures 3, University of Oxford, 27-28 March, 2019.

The Symposium on Compositional Structures (SYCO) is an interdisciplinary series of meetings aiming to support the growing community of researchers interested in the phenomenon of compositionality, from both applied and abstract perspectives, and in particular where category theory serves as a unifying common language. The first SYCO was in September 2018 at the University of Birmingham. The second SYCO was in December 2019, at the University of Strathclyde, each attracting about 70 people.

We welcome submissions from researchers across computer science, mathematics, physics, philosophy, and beyond, with the aim of fostering friendly discussion, disseminating new ideas, and spreading knowledge between fields. Submission is encouraged for both mature research and work in progress, and by both established academics and junior researchers, including students.

Submission is easy, with no format requirements or page restrictions. The meeting does not have proceedings, so work can be submitted even if it has been submitted or published elsewhere. Think creatively—you could submit a recent paper, or notes on work in progress, or even a recent Masters or PhD thesis.

While no list of topics could be exhaustive, SYCO welcomes submissions with a compositional focus related to any of the following areas, in particular from the perspective of category theory:

• logical methods in computer science, including classical and quantum programming, type theory, concurrency, natural language processing and machine learning;

• graphical calculi, including string diagrams, Petri nets and

reaction networks;

• languages and frameworks, including process algebras, proof nets, type theory and game semantics;

• abstract algebra and pure category theory, including monoidal

category theory, higher category theory, operads, polygraphs, and

relationships to homotopy theory;

• quantum algebra, including quantum computation and representation theory;

• tools and techniques, including rewriting, formal proofs and proof assistants, and game theory;

• industrial applications, including case studies and real-world

problem descriptions.

This new series aims to bring together the communities behind many previous successful events which have taken place over the last decade, including “Categories, Logic and Physics”, “Categories, Logicand Physics (Scotland)”, “Higher-Dimensional Rewriting and Applications”, “String Diagrams in Computation, Logic and Physics”, “Applied Category Theory”, the “Simons Workshop on Compositionality”, and the “Peripatetic Seminar in Sheaves and Logic”.

SYCO will be a regular fixture in the academic calendar, running

regularly throughout the year, and becoming over time a recognized venue for presentation and discussion of results in an informal and friendly atmosphere. To help create this community, and to avoid the need to make difficult choices between strong submissions, in the event that more good-quality submissions are received than can be accommodated in the timetable, the programme committee may choose to *defer* some submissions to a future meeting, rather than reject them. This would be done based largely on submission order, giving an incentive for early submission, but would also take into account other requirements, such as ensuring a broad scientific programme. Deferred submissions can be re-submitted to any future SYCO meeting, where they would not need peer review, and where they would be prioritised for inclusion in the programme. This will allow us to ensure that speakers have enough time to present their ideas, without creating an unnecessarily competitive reviewing process. Meetings will be held sufficiently frequently to avoid a backlog of deferred papers.

### Invited speakers

• Marie Kerjean, INRIA Bretagne Atlantique

• Alessandra Palmigiano, Delft University of Technology and University of Johannesburg

### Important dates

All times are anywhere-on-earth.

• Submission deadline: Friday 15 February 2019

• Author notification: Wednesday 27 February 2019

• Registration deadline: Wednesday 20 March 2019

• Symposium dates: Wednesday 27 and Thursday 28 March 2019

### Submissions

Submission is by EasyChair, via the following link:

• https://easychair.org/conferences/?conf=syco3

Submissions should present research results in sufficient detail to allow them to be properly considered by members of the programme committee, who will assess papers with regards to significance, clarity, correctness, and scope. We encourage the submission of work in progress, as well as mature results. There are no proceedings, so work can be submitted even if it has been previously published, or has been submitted for consideration elsewhere. There is no specific formatting requirement, and no page limit, although for long submissions authors should understand that reviewers may not be able to read the entire document in detail.

### Financial support

Some funding is available to cover travel and subsistence costs, with a priority for PhD students and junior researchers. To apply for this funding, please contact the local organizers Antonin Delpeuch (antonin.delpeuch@cs.ox.ac.uk) or Ben Musto (benjamin.musto@cs.ox.ac.uk) with subject line “SYCO 3 funding request” by March 6, with a short statement of your current status, travel costs and funding required.

### Programme committee

Fatimah Ahmadi, University of Oxford

Corina Cirstea, University of Southampton

Bob Coecke, University of Oxford

Carmen Maria Constantin, University of Oxford

Antonin Delpeuch, University of Oxford

Brendan Fong, Massachusetts Institute of Technology

Dan Ghica, University of Birmingham

Giuseppe Greco, Utrecht University

Helle Hvid Hansen, Delft University

Jules Hedges, University of Oxford

Chris Heunen, University of Edinburgh

Dominic Horsman, University of Grenoble

Dimitri Kartsaklis, Apple

Aleks Kissinger, Radboud University Nijmegen

Alexander Kurz, Chapman University

Jean-Simon Lemay, University of Oxford

Martha Lewis, University of Amsterdam

Dan Marsden, University of Oxford

Samuel Mimram, École Polytechnique

Nina Otter, UCLA

Simona Paoli, University of Leicester

Robin Piedeleu, University of Oxford

David Reutter, University of Oxford

Christine Tasson, Paris Diderot University

Jamie Vicary, University of Birmingham

Tamara von Glehn, University of Cambridge

Quanlong Wang, University of Oxford

Gijs Wijnholds, Queen Mary University of London

Philipp Zahn, University of St.Gallen