polarization

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polarization The tendency towards concentration at two opposing extremes, observed by sociologists in a large number of diverse contexts. For example, on the basis of research on the Isle of Sheppey, R. E. Pahl (Divisions of Labour, 1984) identified a process of social polarization which was said to be producing in Britain a division into ‘work rich’ and ‘work poor’ households. Pahl argued that opportunities in both the formal and informal sectors of the economy tended to cluster in the same households; or, put somewhat differently, that households whose members were unemployed did not (indeed according to Pahl could not) compensate for this by informal economic activities in the hidden, underground, or so-called black economy.

Many sociological typologies are descriptions of polar types or extremes: one obvious example is Ferdinand Tönnies's distinction between Gemeinschaft (community) and Gesellschaft (association). Sociologists are also prone to polarization when describing processes of social change–as, for example, in Karl Marx's account of the polarization of classes in capitalist societies into the ‘two great hostile camps’ of bourgeoisie and proletariat.

polarization The phenomenon in which electromagnetic waves, such as light waves, vibrate in a preferred plane or planes; or the process of confining the vibrations to certain planes. In unpolarized light the vibrations are equally distributed in all directions perpendicular to the direction of propagation of the wave. If all the vibrations are confined to one plane, the light is said to be plane-polarized (or linearly polarized). If the light in one plane is out of phase with the light in the plane at right angles to it (i.e. if the peaks and troughs of the waves are not in step), then the light is said to be circularly polarized. If all these phenomena occur together, the light is said to be elliptically polarized. Plane polarization is usually caused by scattering, and circular polarization by strong magnetic fields. Circularly and elliptically polarized light can also be produced by a wave plate. See also stokes parameters.