We are 129 members of the academic community in the United Kingdom and beyond, including Austria, China, Finland, France, Germany, Iceland, Italy, Korea, Mexico, Russia, Serbia, Slovenia, Spain, Sweden, and the US, working at the forefront of computer science, mathematics and machine learning.

We are deeply concerned about the arrest of our colleague, Professor Abbas Edalat, in Iran (Report, 3 May).

Many of us have known Abbas for decades as a kind, caring, decent and honourable man, of great intellect and integrity.

It is particularly surprising that Abbas was arrested specifically in Iran. He deeply respects his own rich heritage, background and ethnicity, and we have heard him say only positive things about the Iranian nation and people. He has always been ready to express his love for his native country.

In addition to being a prominent academic, making fundamental contributions to mathematical logic and theoretical computer science, Abbas has worked ceaselessly to bridge the gap in technology, education and development between the developed and developing worlds.

Abbas has taught many generations of students at Imperial College. Some of us have written our PhD dissertations under his supervision. Many of us owe Abbas our own achievements in computer science, mathematics and machine learning – strategic areas of research for the United Kingdom and for the world – through his generous teaching, advice, and truly visionary thought leadership over many decades.

In addition to inflicting inexplicable suffering on our colleague, teacher and friend, Abbas’s detention is causing a lot of harm to the academic community in the United Kingdom, in Iran and worldwide.

By signing this letter, we are not trying to make a political statement or influence international affairs one way or another. We are expressing concern for our colleague, teacher and friend.

We are all extremely concerned about Abbas’s situation and would humbly solicit all those who can help to facilitate his release.

Prof Samson Abramsky, FRS, Christopher Strachey Professor of Computing, Fellow, Wolfson College, University of Oxford

Prof V. Michele Abrusci, Professore Ordinario, Logica e Filosofia della Scienza, Dipartimento di Matematica e Fisica, Università Roma Tre

Prof Luca Aceto, Professor, School of Computer Science, Reykjavik University, Iceland

Prof Marcello D’Agostino, Professor of Logic, Department of Philosophy, Head of Doctoral School in Philosophy and Human Sciences, University of Milan, Italy

Prof Fabio Alessi, Associate Professor, University of Udine, Italy

Ignacio Fábregas Alfaro, IMDEA Software Institute, Madrid, Spain

Dr. Mauricio Alvarez-Manilla, Quantitative Modeller; Prof Abbas Edalat’s former PhD student

Prof Davide Ancona, Associate Professor at Dipartimento di Informatica, Bioingegneria, Robotica e Ingegneria dei Sistemi (DIBRIS), Università of Genova, Italy

Prof Bruno Apolloni, Full Professor in Computer Science, Department of Computer Science, the Milan University, Italy

Dr. Rob Arthan, Visiting Academic, School of Electronic Engineering and Computer Science, Queen Mary, University of London

Prof Andrea Asperti, Department of Informatics, Science & Engineering (DISI), Alma Mater Studiorum - Università di Bologna

Prof Gianfranco Balbo, Professor, Computer Science Department, University of Torino, Italy

Prof Stefano Baratella, Dipartimento di Matematica, Università di Trento, Italy

Prof Franco Barbanera, Associate Professor, Department of Mathematics and Computer Science (DMI), University of Catania, Italy

Prof Lev D. Beklemishev, Steklov Mathematical Institute of Russian Academy of Sciences in Moscow, Russia

Prof Alessandro Berarducci, Dipartimento di Matematica, Università di Pisa

Dr. Martin Berger, Lecturer in Foundations of Computation (Informatics), University of Sussex

Dr. Ulrich Berger, Reader at the Department of Computer Science, Swansea University

Dr. Paul Alexander Bilokon, Lecturer in Machine Learning, Department of Mathematics, Imperial College London; Founder and CEO, Thalesians Ltd; Prof Abbas Edalat’s former PhD student

Dr. Daniela Briola, Researcher at University of Milan Bicocca, DISCO department, Italy.

Prof Alan Bundy, FRS, CBE, FREng, School of Informatics, University of Edinburgh.

Dr. Peter Buneman, FRS, FRSE, FACM, Professor of Database Systems, University of Edinburgh

Prof Olivia Caramello, Assistant Professor, University of Insubria – Como, Italy

Dr. Giuliano Casale, Senior Lecturer, Department of Computing, Imperial College London

Prof Alessandra Cherubini, Full Professor of Algebra, Dipartimento di Matematica, Politecnico di Milano

Prof Agata Ciabattoni, Vienna University of Technology, Austria

Prof Nicoletta Cocco, DAIS – Ca’ Foscari University, Italy

Prof Roberto Di Cosmo, Computer Science Professor, on leave at INRIA from IRIF/University Paris Diderot

Prof Jim Cunningham, Reader Emeritus, and Senior Research Fellow, Department of Computing, Imperial College London

Prof Pierre-Louis Curien, Director of Research at Centre National de la Recherche Scientifique (CNRS), France

Prof Ferruccio Damiani, Associate Professor, Coordinator of the MoVeRe research group, Dipartimento di Informatica - Università degli Studi di Torino

Prof Anuj Dawar, Professor of Logic and Algorithms, Department of Computer Science and Technology, University of Cambridge

Prof George Danezis, Professor of Security and Privacy Engineering, University College London

Prof Pierpaolo Degano, Full Professor, Computer Science Department, University of Pisa, Italy

Prof Mariangiola Dezani-Ciancaglini, Departimento di Informatica, Università di Torino

Prof Susanna Donatelli, Full Professor of Computer Science, University of Torino, Italy

Prof Gilles Dowek, researcher at Inria at the LSV, professeur attaché at the ENS Paris-Saclay, France

Dr. Serdar Erbatur, IMDEA Software Institute, Madrid, Spain

Dr. Martín Hötzel Escardó, Reader in Theoretical Computer Science, School of Computer Science, University of Birmingham

Prof Lorenzo Tortora de Falco, Associate Professor of Logic, Università Roma Tre, Italy

Prof José Fiadeiro, Professor of Computer Science and Head of Department, Royal Holloway University of London, UK; member of Academia Europaea

Dr. Nicola Gambino, Associate Professor in Pure Mathematics, School of Mathematics, University of Leeds

Prof Giangiacomo Gerla, Department of Mathematics, Università degli Studi di Salerno

Prof Silvia Ghilezan, Faculty of Technical Sciences, University of Novi Sad, Serbia

Prof Roberto Giacobazzi, Dipartimento di Informatica, Università di Verona, Italy

Prof Pietro Di Gianantonio, Associate Professor, University of Udine, Italy

Dr. Anandha Gopalan, Senior Teaching Fellow, Department of Computing, Imperial College London

Prof Roberto Gorrieri, Dipartimento di Informatica – Scienza e Ingegneria, Università di Bologna, Italy

Dr. Matthew Hague, Reader and EPSRC Early Career Fellow, Department of Computer Science, Royal Holloway University of London

Ann Halford, Research Group Administrator, Department of Computing, Imperial College London

Prof Dr. Reiko Heckel, Professor in Software Engineering, Head of Computer Science, Department of Informatics, University of Leicester

Dr. Chris Heunen, Senior Research Fellow, Quantum Informatics, School of Informatics, University of Edinburgh

Prof Jane Hillston, FRSE, Director of Research and Head of School Designate, School of Informatics, University of Edinburgh

Prof Edward A. Hirsch, Research Lead, Laboratory of Mathematical Logic, Steklov Institute of Mathematics at St. Petersburg

Prof Furio Honsell, Full Professor, University of Udine, Italy

Prof Hykel Hosni, Associate Professor in Logic at the University of Milan, Italy

Prof Michael Huth, Professor of Computer Science, Faculty of Engineering, Department of Computing, Imperial College London

Prof J. M. E. Hyland, Professor of Mathematical Logic, University of Cambridge

Prof Marina Jirotka, Professor of Human Centred Computing, Department of Computer Science, University of Oxford

Prof Peter Johnstone, Emeritus Professor of the Foundations of Mathematics, University of Cambridge

Prof Cliff Jones, Professor of Computing Science at the Newcastle University

Prof Achim Jung, Professor of Computer Science, The University of Birmingham; member of the Birmingham Theory Group

Dr. Michal Konečný, Lecturer in Computer Science, Aston University

Prof Alexander Kurz, Professor of Computer Science, University of Leicester

Prof Robert Kowalski, Professor Emeritus and Distinguished Research Fellow, Department of Computing, Imperial College London

Prof Marta Zofia Kwiatkowska, Professor of Computing Systems, Fellow, Trinity College, University of Oxford

Prof Jimmie Lawson, Department of Mathematics, Louisiana State University

Prof Marina Lenisa, Associate Professor, University of Udine, Italy

Prof Giacomo Lenzi, Department of Mathematics, Università degli Studi di Salerno

Dr. Paul Blain Levy, Reader in Theoretical Computer Science, University of Birmingham

Prof Ugo de’Liguoro, Associate Professor of Computer Science, Dipartimento di Informatica, Università di Torino, Italy

Prof Paolo Lipparini, Mathematics Department, University of Tor Vergata Rome, Italy

Dr. John Longley, Lecturer, School of Informatics, University of Edinburgh; Member of Laboratory for Foundations of Computer Science, Director of Quality

Prof Alberto Marcone, Dipartimento di Scienze Matematiche, Informatiche e Fisiche, Università di Udine

Prof Simone Martini, Professor of Computer Science, Head of Department of Computer Science and Engineering, Alma Mater Studiorum - Università di Bologna

Prof Viviana Mascardi, DIBRIS – Dipartimento di Informatica, Bioingegneria, Robotica e Ingegneria dei Sistemi, Università Degli Studi di Genova, Italy

Prof Andrea Masini, Department of Computer Science, University of Verona, Italy

Prof Marino Miculan, Associate Professor, University of Udine, Italy

Prof Michael W. Mislove, Pendergraft Herbert Buchanan Professor, Deparment of Mathematics, Tulane University; Professor and Chairman, Computer Science Department, Tulane University, US

Prof Eugenio Moggi, Professor of Computer Science, the University of Genoa, Italy

Prof Faron Moller, FLSW, Department of Computer Science, Swansea University

Prof Sara Negri, Professor of Theoretical Philosophy, University of Helsinki, Finland

Dr. Luke Ong, Professor of Computer Science, University of Oxford

Prof Catuscia Palamidessi, Director of Research at INRIA, France, Leader of the equipe Comète

Dr. Giuseppe Perelli, Research Assistant, Department of Computer Science, University of Oxford

Prof Giuseppe Persiano, Professor of Computer Science, University of Salerno, Italy

Prof Rossella Petreschi, Dipartimento di Informatica, Sapienza, Università di Roma, Italy

Prof Mario Piazza, Full Professor of Logic and Philosophy of Mathematics, Scuola Normale Superiore, Classe di Lettere e Filosofia, Pisa, Italy

Prof Andrew M. Pitts, Professor of Theoretical Computer Science, Department of Computer Science and Technology, University of Cambridge

Prof Gordon Plotkin, FRS, Laboratory for Foundations of Computer Science, School of Informatics, The University of Edinburgh

Dr. Giuseppe Primiero, Department of Computer Science, Middlesex University London

Dr. Maurizio Proietti, Senior Researcher, Istituto di Analisi dei Sistemi ed Informatica “A. Ruberti” Consiglio Nazionale delle Ricerche (IASI-CNR), Rome, Italy

Prof Davide Quaglia, Computer Engineer and PhD, Assistant Professor Dip. Di Informatica, Università degli Studi di Verona, Italy

Dr. Bernhard Reus, Senior Lecturer, Department of Informatics, University of Sussex

Prof Romeo Rizzi, Associate Professor, Operations Research, University of Verona, Italy

Prof Edmund Robinson, Professor of Computer Science, Head of Theory Group, Queen Mary, University of London

Prof Simona Ronchi Della Rocca, Full Professor of Foundations of Computer Science, Dipartimento di Informatica, Università di Torino

Prof Bill Roscoe, FREng, Professor and former Head of Department, Computer Science, University of Oxford

Prof Giuseppe Rosolini, Professor of Mathematical Logic, Dipartimento di Matematica, Università di Genova, Italy

Dr. Sasha Rubin, Postdoctoral Researcher in Computer Science, ASTREA Laboratory, University of Naples “Federico II”, Italy

Prof Berc Rustem, Emeritus Professor, Faculty of Engineering, Department of Computing, Imperial College London

Prof Mark Ryan, Professor of Computer Security, University of Birmingham

Prof Giovanni Sambin, Professor of Mathematical Logic, Dipartimento di Matematica, Università di Padova, Italy

Prof Donald Sannella, FRSE, Professor of Computer Science, Laboratory for Foundations of Computer Science, School of Informatics, University of Edinburgh

Prof Giuseppe Scollo, Dipartimento di Matematica e Informatica, Università degli Studi Catania, Italy

Prof Dana S. Scott, FBA, FNAS, FAAS, ACM, Emeritus Hillman University Professor of Computer Science, Philosophy, and Mathematical Logic at Carnegie Mellon University; winner of the ACM Turing Award, USA

Prof Donia Scott, Professor of Computational Linguistics, University of Sussex

Dr. Monika Seisenberger, Associate Professor in Theoretical Computer Science, Swansea University

Prof dr. Alex Simpson, Professor of Computer Science, Faculty of Mathematics and Physics, University of Ljubljana, Slovenia

Prof Aaron Sloman, Honorary Professor of Artificial Intelligence and Cognitive Science School of Computer Science, The University of Birmingham

Alexander V. Smal, Laboratory of Mathematical Logic, Steklov Institute of Mathematics at St. Petersburg, Russia

Prof Luca Spada, Associate Professor, Department of Mathematics, University of Salerno, Italy

Dr. Iain Stark, Senior Lecturer in Computer Science, The University of Edinburgh

Prof Kostas Stathis, Department of Computer Science, Royal Holloway, University of London

Prof Sam Staton, Associate Professor, Department of Computer Science, University of Oxford

Prof Perdita Stevens, Professor of Mathematics of Software Engineering, University of Edinburgh; former colleague of Prof Abbas Edalat

Prof Dr. Thomas Streicher, Professor of Mathematics at Technische Universität Darmstadt, Germany

Prof Walid Mohamed Taha, Professor of Computer Science at the School of Information Technology, Halmstad University, Sweden

Dr. Paul Taylor, Author, Mathematician, and Computer Scientist, University of Birmingham (honorary), formerly Imperial College London

Prof Carlo Toffalori, Professor, Università di Camerino, Italy

Prof Paolo Turrini, Assistant Professor, Department of Computer Science, the University of Warwick

Prof Giorgio Valentini, Professor of Computer Science, University of Milan, Italy

Prof Daniele Varacca, Professor of Computer Science, Université Paris Est – Créteil, France

Prof Matteo Viale, Associate Professor in Mathematical Logic, Dipartimento di Matematica, Università di Torino

Dr. Steve Vickers, Senior Lecturer, School of Computer Science, University of Birmingham

Dr. Mark Wheelhouse, Senior Teaching Fellow, 2nd Year Coordinator, Department of Computing, Imperial College London; colleague of Prof Abbas Edalat

Dr. Graham White, Senior Lecturer, School of Electronic Engineering and Computer Science, Queen Mary, University of London

Prof Glynn Winskel, Professor of Computer Science, University of Cambridge

Prof Martin Ziegler, Associate Professor, Complexity and Real Computation Lab, KAIST School of Computing, Daejeon, Korea