This blog post features an opinion piece from PLOS ONE Section Editor in Urban Studies Dr. Diego Rybski about the interplay between shifts in work, friction of distance (or of space), transport patterns, and urban decline. He discusses where opportunities for new insight may be found.
Diego Rybski is a senior researcher at the Potsdam Institute for Climate Impact Research (PIK) and at the Wuppertal Institut. In addition, he is external faculty in the Complexity Science Hub in Vienna and a section editor at PLOS ONE (Urban Studies). Currently, he also serves as the coordinator of the UPon project (Urban Percolation) funded by the German Research Foundation (DFG).
Diego holds a PhD in Physics from Justus-Liebig-Universität (Germany). He was a visiting scholar at Bar-Ilan University (Israel) and a Postdoctoral Fellow at the City College of New York (CCNY). Between 2019 and 2021, he was a Feodor Lynen Research Fellow of the Alexander von Humboldt Foundation at the Department of Environmental Science, Policy, and Management at the University of California, Berkeley.
His research focuses on cities and urban systems—specifically, on cities as complex systems, cities and climate change (mitigation/adaptation), and urban climate and the urban heat island effect. Diego was born in Brazil, grew up between Germany, where his family is from, and Brazil, and is currently based in Berlin (Germany).
Opinion: the ‘death of the distance’ revisited
Digitization, the Internet, and Information & Communications Technology (ICT) dramatically change the way we work . Service is the dominating sector and continues to expand . However, offices – the traditional service-sector working place – are out of fashion. The home office represents a popular working mode, which became necessary during COVID-19 lockdowns and was facilitated by ICT. Technologies, such as video-calls and -meetings, collaborative writing, and cloud services in general, are not only efficient tools but also make personal presence dispensable.
In this post, I discuss a specific example of remote work and contextualize it beyond ICT in relation to urban decline, gravity, and sustainability.
Braesemann et al.  investigated a fully remote labor market and studied to what extent remote work connects employers and workers in different countries. Online labor platforms are market places that bring together employers and workers. Since they are online, they facilitate the matching of partners across the globe. For example, a software company based in North America could give a job assignment to a coder located in South Asia – the platform helps them find each other and coordinate the full work pipeline from service contracting to delivery.
The authors reported that – although in principle space-independent – cities draw in remote jobs, whereas rural areas fall behind. This result suggests that traditional agglomeration economies also play a role in the virtual world. A reason might be that workers with in-demand skills attract profitable jobs, while others face intense competition and obtain low wages  – just like in the offline world.
Although information and communication technologies have been predicted to bring economic activities to rural areas, the actual development is the opposite, and knowledge spillovers (exchange of ideas among individuals) drive further urbanization . Large cities seem to attract skilled and creative employees, irrespective of their work being online or offline. This is a finding that is also fundamental to urban scaling [5, 6], in that large cities generate, for example, more GDP per capita than small ones (known as increasing returns to scale).
However, ICT changes not only work but also many other aspects of our lives. Streaming has progressively replaced traditional ‘linear’ television as well as the already weakened movie theaters. Moreover, e-commerce (online shopping) drastically reduces the revenues of retail stores. Many of them close, and bankrupt department stores leave (metaphorical) holes in the city centers. Deserted inner cities represent serious challenges, as for example in Germany where pedestrian-only areas have traditionally played a vital role in the cities’ spatial, social, and economic functioning.
These considerations lead to the question: what role does space play and what role will it will play in the future? Historically, city size is limited by the time needed to move within them . In contrast to walking or riding a horse, modern means of transport have enabled the formation of larger cities. Today, ICT makes traveling even more efficient by means of real-time routing or ride-sharing . But what happens if we think ahead about the impacts of digitization, for example where home offices reduce the need to commute, and where remote work is even commute-free?
Space, of course, involves a range of aspects but here I want to focus on one. In geography, one speaks about the friction of distance (also referred to as friction of space ) . In our daily life we go from A to B and the distance, travel time, and costs all represent a friction. Usually, this friction is modeled with a decreasing function: the likelihood to make a trip decreases with the distance.
Often a power-law is used to model spatial flows, where the flow is proportional to the distance raised to a negative power (fA,B ∼ dA,B-γ). The exponent γ characterizes the friction of distance under the umbrella of gravitational models [9, 10]. A large value means that distance has a strong effect, meaning that long trips are hard and rare. A small γ means distance has only weak influence, so traveling is easy, and long trips are frequent. In fact, many mobility studies report displacement distributions that follow power-laws [11, Sec.3.3.2]. Similar models are used for all kinds of spatial processes, including communication and interaction between people at a distance.
As a consequence of new ICT developments, we would expect a weakening of the friction of distance (a smaller exponent γ). On the one hand, virtually, we can meet ideally anyone on the globe (γ ≈ 0) and the only restrictions, assuming access to the Internet, are time zones. On the other hand, we do not need to travel, because many things can be done from home (home office, e-commerce) and for these purposes distance becomes essentially irrelevant (γ → 0; strictly speaking, the distance is shifted from the consumers to the vendors/logistics). Last but not least, if we travel, ever more efficient transport permits easy and long trips (for the sake of the argument, we disregard traffic jams).
To date, it is unresolved if and how the γ exponent is changing over time or as a consequence of digitization. Maybe new ICT developments mostly alter the prefactor c in fA,B = c · dA,B-γ. Already in the early Internet age (web 1.0) the death of the distance was anticipated .
In 2022, a highly subsidized mobility experiment was conducted in Germany. Intended to compensate for rising costs of living and with the purpose of incentivizing a modal shift from car to public transport, during the months June–August the 9-Euro-Ticket (9ET) was offered. All regional and local public transport could be used across the entire country for 9 Euro per month. From the cost perspective, this ticket implies γ ≃ 0 and people could travel even long distances. And indeed, many people used connections of regional trains to travel across Germany. Because lower-income demographics had the chance to travel, the 9-Euro-Ticket had a social benefit.
It is disputed to what extent the original expectation of stimulating a shift from car to public transport was met but it was estimated that the intervention reduced air pollution by more than six percent  and, mostly, the model has been positively evaluated . It is worth mentioning that in 2023 the “Deutschland Ticket” (“Germany Ticket”) was introduced, with the same access but for 49 Euro per month. A big advantage is that city visitors do not need to understand the local ticket pricing system and can use the same ticket in whatever city within Germany. Please note that, in terms of travel time, one can assume larger γ for such tickets than for long distance trains that go faster than regional trains (on large scales).
In order to make mobility more sustainable, it has been proposed to avoid trips or to reduce their length, to shift the means to active transport such as walking and cycling, and to improve the transport technology (avoid, shift, improve; ASI) . The idea of avoiding and reducing trips corresponds to larger γ, i.e. increasing the friction of space. Larger γ, however, contrasts with the idea of the 9ET. As a “consumer” we want to conveniently go anywhere and with little effort. This represents a sort of paradox requiring further consideration.
In summary, by considering selected implications of the digital revolution I argue that while home office and remote work have become popular models, traditional structures such as agglomeration economies persist. The reason could be persisting friction of space, despite transitional ICT developments. There is a research need to understand if and how the friction of distance (represented by the γ exponent) evolves and how sustainability and consumer needs can be reconciled. How do the transport demand and the selection of modes need to change?
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