Proximity/Space

Physical Space: Gravity and Form

Social network research addresses the role of physical space in at least three distinct ways: by focusing on the influence of space on networks, the consequences of networks for space, and the structuring of space by networks.

In some cases, the focus is on understanding how the physical environment and arrangement of social entities within it influences their interactions. Public space in a neighborhood can provide a site for the formation of new relationships, while meandering networks of residential streets can facilitate unplanned encounters. Proximity in physical space is also important, and is typically associated with more frequent or intense interaction. For example, individuals living on the same street are likely to interact with one another more than those living elsewhere in the neighborhood. A similar pattern is also observed for aggregates like firms or cities, and is often described using a gravity model that borrows from Isaac Newton's classical formulation:

The intensity of interaction between two entities (e.g., phone calls, migration) is proportional to the product of their sizes and inversely proportional to the square of the distance between them. However, noting advances in communication and transportation technology, some have questioned the extent to which physical space and distance continues to structure interactions and networks.

Because social networks are often localized in physical space (e.g., among neighborhood residents), in other cases, the focus is on understanding the social consequences of networks for space. Dense networks of interaction can serve to transform merely physical spaces into socially meaningful places. For example, while a neighborhood may have an objective physical location (i.e., its latitude and longitude), its neighborhood character derives from the relationships that exist among its residents and from their repeated interactions with one another. Similarly, while a region like Silicon Valley can be described by its spatial boundaries, its social and economic significance depends on the networks that exist among technology firms located within the space.

Finally, much attention has been devoted to mapping the network structure of physical space. At the perceptual level, individuals navigate their surroundings using mental maps composed of such network elements as paths, such as streets and sidewalks; edges, like walls and buildings; and nodes, such as intersections. More objectively, network methodologies have been used as urban planning tools to study such urban features as the organization of urban infrastructures. Reductions in traffic congestion, for example, may be sought by comparing the efficiency of the hub-and-spoke structured street systems found in older cities with the grid-based systems found in newer cities.

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