Spatial Concepts

Spatial mobility is an essential component of the way societies organise space. It has been defined in various ways, in reference to different registers of observation and conceptualisation. In its most frequent acceptation, mobility is movement or travel from one «place» to another. This movement can concern people, but also material and immaterial goods, and information. The unit of measurement naturally depends on what is travelling, and can for instance be in terms of numbers of (...)

An environment or medium is said to be isotropic if its physical properties are identical in all directions. A «system» will be termed isotropic if its (macroscopic) properties are invariant in relation to a particular direction, and therefore none of these properties is directionally dependent. Should one of its properties be directional, the system is not isotropic, but anisotropic. A physical magnitude can also be said to be anisotropic or isotropic according to whether or not it is (...)

The concept of polarisation covers two distinct acceptations in Geography:
A classical acceptation synonym of concentration of matter and energy. Polarisation is the attraction exerted by a place on a more or less extended and heterogeneous space that is in a situation of dependency with respect to this centre. Space is compared to a magnetic field in which a place, assimilated to a pole (generally a city or a region) exerts a magnetisation proportional to its population, to its activities (...)

A system is a set of sets : set of elements linked with each other through relations which form a set of interactions ; presence of positive and/or negative retro-action loops is an indispensable element of a system definition. Defined in this way, a system forms a totality, whose limits may be defined. Most systems in which human sciences are interested are open; they maintain relations with a part of the outside world which constitutes their environment. Inputs in the system condition its (...)

Although the notion of spatial interaction plays a central role in the definition of contemporary geography, it is extremely difficult to define, so various are the definitions that have been proposed for it. An attempt may however be made to make a rough classification of these definitions in order to distinguish between what constitutes the heart of the notion, and what points to extensions of it and the theoretical issues it raises.
1. The spatial interaction and gravity model.A (...)

In a very broad acceptation, discontinuity is what separates two neighbouring and different spatial sets. One can distinguish the elementary discontinuity, built on a single indicator, which is a useful but frail indication, from the structural discontinuity, superposition of numerous converging elementary discontinuities measured on basis of a coherent set of indicators. The latter may be defined as the spatial form of transition between two neighbouring systems.
Discontinuity may be (...)

In common language, situation of an object on the Earth surface is the same as its position. In everyday use, both terms: situation and position, are used indiscriminately. They refer to reference points conventionally designated by means of an explicit reference system, namely geographical coordinates (latitude, longitude).
In geographical discourse, situation defines a relative location in space. For a given place, it is expressed with respect to that of other places whose physical or (...)

The word "structure" comes from Latin struere which means to build, to arrange, and contains the notion of an organised thing. Spatial structures exist, because geographical space is not constituted by a set of unique places, occupying random locations. The successive choices of actors and, more broadly, the answers given by societies to the issue of space control , obey to certain logics, even if the overlapping and interweaving of these logics make their legibility more or less evident; (...)