Welcome

I am Vincent.

About Me

I'm a 28-year-old urban scientist currently living in Paris, France. Throughout my research career, I've explored a broad range of urban phenomena. However, my current role finds me working as a civil servant for the French government, where I contribute to various aspects of urban development and public policies.

Pre-order my new book on City Population online!

About My Work

Nov 2022 "La modélisation des villes : une approche physique du phénomène urbain" in La Jaune et la Rouge.
Nov 2020 "Comment un village peut devenir une mégalopole" in The Conversation.
Aug 2019 "Transit Can Save the Environment, Just Not How We Expected" in Bloomberg.

Research on Cities

Urban Population

The study of population is the most natural and, consequently, the oldest field in urban research. Population serves as a valuable metric for assessing the significance, or one might say, the success of a city. First and foremost, it is relatively easy to measure, and population can be correlated with a wide array of other urban factors, including wealth, crime, innovation, traffic congestion, and public transportation development.

But what is the 'typical' size of a city? Economics struggles to answer this question. As Paul Krugman points out in his famous article 'The Mystery of Urban Hierarchy,' economics predicts that cities are in equilibrium and should therefore be close to an optimal size, which, in practice, is not the case.

I have shown that:

  1. The distribution of population across cities is unequal, but it does not follow Zipf's law.
  2. Population dynamics are driven by migratory fluxes, which can rapidly change the fate of a city on very short timescales.

Car Traffic Mitigation

Car traffic in cities has been extensively studied in recent decades. My research suggests that urban density is not the most critical variable controlling car-related factors. Instead, the size of the city's area and the density of public transport play a more significant role. Mitigating traffic issues, including CO2 emissions, can be achieved by reducing the urbanized area's size or, more realistically, by enhancing either the density of public transport or its accessibility. In particular, increasing population density is a viable approach only if it also increases the proportion of individuals with access to public transport.

Income Dynamics

Urban inequality stands as a formidable challenge in the 21st century, casting a shadow over the urban landscape. Gentrification, that well-documented phenomenon where affluent residents descend upon low-income neighborhoods, ushering in transformation while displacing established communities, has taken center stage. Yet, equally profound but less explored is the counterflow of gentrification, where pockets of a city witness an economic decline. My research has unveiled a key insight: the financial destiny of an area is intricately intertwined with the economic well-being of its adjacent neighborhoods. To illustrate these findings, we have projected the likelihood of areas undergoing shifts in their income status, looking forward to the year 2030, using Boston and Paris as illustrative examples.

Education (Find my complete résumé here)

Aug 2022 Doctorate of Philosophy, Paris-Saclay University, Paris, France
Thesis: "The modelling of urban systems" – Supervisor: Dr. Marc Barthelemy
Aug 2019 Master of Science, École des ponts, Paris, France
Public Policies and Actions for Sustainable Development. Government executive program.
Aug 2018 Master of Science, École normale supérieure, Paris, France
Theoretical physics -- Statistical physics.
Aug 2017 Master of Science and Engineering Degree, École polytechnique, Paris, France
Grande école

Publications

Handbook

Statistics and Dynamics of Urban Populations: Empirical Results and Theoretical Approaches, Verbavatz, V., & Barthelemy, M. Oxford Universty Press. Scheduled for issuance on December 21st, 2023.

Journal publications