time-space convergence

Places are separated by absolute distance and by time. With improvements in communication systems and methods of transport, this time-distance diminishes. D. G. Janelle (Professional Geographer 20) illustrated this with figures for the journey time between London and Edinburgh:

date	journey time in minutes	mode of transport
1658	20 000	stage coach
1770	6000	stage coach
1820	2700	stage coach
1860	700	railway
1950	200	aeroplane

and expressed the rate at which this takes place as:

TT₁ - TT₂Y₁ - Y₂

where TT₁ and TT₂ are travel times in different years and where Y₁ and Y₂ are the relevant years.

In essence, time-space convergence means that the friction of distance—a concept fundamental to conventional central place theory, diffusion theory, and location theory—is lessening. However, A. Horner (Geography 85) argues that ‘not too much should be read into changes in rail travel time—that much of Europe's population lives outside a high-speed world…and that…developments in telecommunications and…the motorway network could have much greater shrinkage effects’.

[Ge]

The process whereby distances become ‘shortened in time’ as the speed of modes of transportation increases.