John W. Hessler, FRGS
Applied Mathematician, Geographic Information Systems Scientist, and Professor in Nice, France
John W. Hessler, FRGS
Applied Mathematician, Geographic Information Systems Scientist, and Professor in Nice, France
When not climbing in the Alps or racing a carbon fiber Pinarello, I am an applied mathematician, geographic information systems (GIS) scientist, and lecturer at Johns Hopkins University, specializing in the spatial modeling and mapping of infectious disease transmission.
In summer 2025, I am a maître de conférences adjoint en mathématiques appliquées et en sciences de l'information géographique théorique, at the Sorbonne Université (Faculté des Sciences et Ingénierie), teaching, The Mathematical and Ontological Foundations of Geographic Information Science: an Introduction to Mereotopology, Toposes, and Category Theory.
I am the director of BIOMAP-LAB AI, where we use bioinformatic and genomic data, machine learning, and advanced geographic information systems, to study the far-from-equilibrium and non-stationary transmission of zoonotic diseases and the movement patterns of their animal hosts.
Our current projects are centered on mapping the spread of highly pathogenic avian H5N1 influenza in wild bird populations; on using wavelet and non-linear approximation methods to study the SARS-CoV-2 pandemic; on trying to understand the medieval patterns of plague transmission in Europe and Eurasia; and on reconstructing the dynamics of the 2014-2016 Ebola epidemic in west Africa.
The author or editor of more than one hundred articles and books, including the New York Times bestseller, MAP: Exploring the World, I am now trying to turn a mess of mathematical course notes into the forthcoming book, The Algebra of Space: Lectures on Mereotopology, Category Theory and the Ontological Foundations of Geographic Information Science.
Interested in the origins and metaphysical foundations of point-free geometries and region based topologies for GIS, I am also working on a mathematical commentary on Alfred North Whitehead’s 1916, La Theorie Relationniste de L’Espace and William Lawvere's Categories of Space and Quantity.
My latest articles, To save lives: lessons of a pandemic cartographer, was published in the Transactions of the Institute of British Geographers (2024), and Mapping the Last Pool of Darkness: a Tribute to Cartographer Tim Robinson (1935-2020), appeared in the Spring 2024 issue ofThe Portolan.
A Fellow of the Royal Geographical Society (FRGS), I find being close to the gentle hum of supercomputers, pondering the complex mathematical knots of topos theory, and exploring the complex labyrinths of Darwin’s tangled bank, strangely comforting.