Dr. Isabelle Chalendar and Dr. Jonathan R. Partington to receive the 2025 G. de B. Robinson Award

Ottawa, ON – The Canadian Mathematical Society (CMS) is pleased to announce that Dr. Isabelle Chalendar (Université Gustave Eiffel) and Dr. Jonathan R. Partington (University of Leeds) are the recipients of the 2025 G. de B. Robinson Award. They are receiving this award for their joint paper, “Phase Retrieval on Circles and Lines”, published in the Canadian Mathematical Bulletin (67:4 [2024], pp 927-935). The G. de B. Robinson Award was inaugurated to recognize the publication of excellent papers in the Canadian Journal of Mathematics (CJM) and the Canadian Mathematical Bulletin (CMB) and to encourage the submission of the highest quality papers to these journals.

Dr. Isabelle Chalendar is a French mathematician who has been the head of the mathematics department at the Université Gustave Eiffel since 2022. She obtained her Ph.D. from the Université de Bordeaux in 1996 under the supervision of Bernard Chevreau. Her research interests include function theory, complex analysis and operator theory, sometimes with applications to semigroup theory. She wrote a book in collaboration with Jonathan Partington entitled “Modern Approaches to the Invariant Subspace Problem” (Cambridge Tracts in Mathematics). Over the past ten years, she has been very involved in promoting greater parity in mathematics among young people.

Dr. Jonathan R. Partington is a British mathematician, who is now an Emeritus professor at the University of Leeds. He obtained his Ph.D. from the University of Cambridge in 1980, under the supervision of Béla Bollobás. His research interests include complex analysis and operator theory, sometimes with applications to systems and control theory. He has written four books and was formerly an editor of the Journal of the London Mathematical Society.

Their joint paper, “Phase Retrieval on Circles and Lines”, addresses the phase retrieval problem, a vibrant and rapidly evolving area of research at the intersection of pure mathematics and engineering. At its core, phase retrieval seeks to reconstruct a signal based solely on the modulus of its representation, without access to phase information. The practical and theoretical significance of this problem is immense, with applications ranging from quantum mechanics to signal processing. In their work, Dr. Chalendar and Dr. Partington present an innovative and modern perspective on the classical results of Perez, enriching the existing framework and pushing the boundaries of the field. Furthermore, they consider the Nevanlinna class—an essential and comprehensive family of functions on the open unit disk—further broadening the scope and applicability of their findings.

What sets this paper apart is the authors’ meticulous treatment of the most general and challenging scenario: equality conditions on two distinct circles within the disk. Through rigorous analysis, they provide definitive results or counterexamples for each possible configuration, demonstrating both mathematical depth and precision. This paper advances understanding of the phase retrieval problem but also lays the groundwork for future explorations in this vital area of mathematics.

Overall, the paper “Phase Retrieval on Circles and Lines” brings significant contributions to the field and has the potential to inspire further innovation. The CMS is proud to award Dr. Isabelle Chalendar and Dr. Jonathan R. Partington the 2025 G. de B. Robinson Award.

About the G. de B. Robinson Award
The G. de B. Robinson Award is named for Gilbert de Beauregard Robinson, the third president of the CMS. Robinson, along with H.S.M. Coxeter, established the Canadian Journal of Mathematics (CJM) and acted as the managing editor for 30 years. The award recognizes outstanding contributions to the CJM or the Canadian Mathematical Bulletin (CMB).

About the Canadian Mathematical Society (CMS)
The Canadian Mathematical Society (CMS) is the main national organization whose goal is to promote and advance the discovery, learning and application of mathematics. The Society’s activities cover the whole spectrum of mathematics including meetings, research publications, and the promotion of excellence in mathematics competitions that recognize outstanding student achievements. The CMS is a registered non-profit, charitable organization and depends on grants, funding, and generous donations from sponsors, benefactors and community members to be able to carry out its activities.

For more information, please contact:

Dr. Adam Van Tuyl (McMaster University) Chair, Publications Committee Canadian Mathematical Society chair-pubc@cms.math.ca

or

Dr. Termeh Kousha Executive Director Canadian Mathematical Society tkousha@cms.math.ca