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The role of complexity for digital twins of cities


We argue that theories and methods drawn from complexity science are urgently needed to guide the development and use of digital twins for cities. The theoretical framework from complexity science takes into account both the short-term and the long-term dynamics of cities and their interactions. This is the foundation for a new approach that treats cities not as large machines or logistic systems but as mutually interwoven self-organizing phenomena, which evolve, to an extent, like living systems.

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Fig. 1: Features of complexity.
Fig. 2: Complexity and digital twins.

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Regarding J.L.F.-V., the views of set out in this article are his own and do not necessarily reflect the official opinion of the European Commission. We thank M. Clarin from COSNET Lab/BIFI for designing Figs. 1 and 2. G.C. acknowledges support from EU Project ‘HumanE-AI-Net’, no. 952026 and from project SERICS (PE00000014) under the NRRP MUR program funded by the EU - NGEU. C.G. acknowledges support from UNAM-PAPIIT projects (IN107919, IV100120, IN105122) and from the PASPA program from UNAM-DGAPA. D.H. acknowledges support through the project ‘CoCi: Co-Evolving City Life’, which has received funding from the European Research Council (ERC) under the European Union Horizon 2020 research and innovation program under grant agreement no. 833168. Y.M. acknowledges support from the Government of Aragon through grant E36-20R (FENOL), and from MCIN/AEI/10.13039/501100011033 through grant PID2020-115800GB-I00. E.A. and M. Batty acknowledge support from the Alan Turing Institute under QUANT2-Contract-CID-3815811 and from the UK Regions Digital Research Facility (UKRDRF) EP/M023583/1 through EPSRC. J.J.R. acknowledges funding from MCIN/AEI/10.13039/501100011033 and Fondo Europeo de Desarrollo Regional (FEDER, UE) under Project APASOS (PID2021-122256NB-C22), and the María de Maeztu Program for units of Excellence in R&D CEX2021-001164-M by MCIN/AEI/10.13039/501100011033. A.S. acknowledges support from project BASIC (PGC2018-098186-B-I00) funded by MCIN/AEI/10.13039/501100011033 and by ‘ERDF A way of making Europe’. The funders had no role in study design, data collection, and analysis, decision to publish, or preparation of the manuscript.

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Caldarelli, G., Arcaute, E., Barthelemy, M. et al. The role of complexity for digital twins of cities. Nat Comput Sci 3, 374–381 (2023).

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