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space-time

(Encyclopedia)space-time, central concept in the theory of relativity that replaces the earlier concepts of space and time as separate absolute entities. In relativity one cannot uniquely distinguish space and time...

time zone

(Encyclopedia)time zone: see standard time.

time-division

(Encyclopedia)time-division: see multiplexing. ...

daylight saving time

(Encyclopedia)daylight saving time (DST), time observed when clocks and other timepieces are set ahead so that the sun will rise and set later in the day as measured by civil time. The amount of daylight on a given...

equal-time rule

(Encyclopedia)equal-time rule, a Federal Communications Commission rule that requires equal air time for all major candidates competing for political office. It was preceded by the fairness doctrine, abolished in 1...

time , in music

(Encyclopedia)time, in music: see tempo; meter; rhythm; syncopation; metronome and musical notation. ...

time and motion study

(Encyclopedia)time and motion study, analysis of the operations required to produce a manufactured article in a factory, with the aim of increasing efficiency. Each operation is studied minutely and analyzed in ord...

period, in geologic time

(Encyclopedia)period, unit of time on the geologic timescale. Periods are shorter than an era and longer than an epoch. Periods are of variable length, generally lasting tens of millions of years, with characterist...

Major Planets of the Solar System (table)

(Encyclopedia)Major Planets of the Solar System ...

day

(Encyclopedia)day, period of time for the earth to rotate once on its axis. The ordinary day, or solar day, is measured relative to the sun, being the time between successive passages of the sun over a stationary o...