Evolution of the World Stage of Global Science from a Scientific City Network Perspective

This paper investigates the stability and evolution of the world stage of global science at the city level by analyzing changes in coauthorship network centrality rankings over time. Driven by the problem that there exists no consensus in the literature on how the spatial unit "city" should be defined, we first propose a new approach to delineate so-called scientific cities. On a high-quality Web of Science dataset of 21.5 million publications over the period 2008-2020, we study changes in centrality rankings of subsequent 3-year time-slices of scientific city co-authorship networks at various levels of impact. We find that, over the years, the world stage of global science has become more stable. Additionally, by means of a comparison with degree respecting rewired networks we reveal how new co-authorships between authors from previously unconnected cities more often connect 'close' cities in the network periphery.