IDEA OF MEASURING CHANGES ) DESIGN OF A CLEPSYDRA
A clock is a device whose functioning is correlated with the configuration of the
Sun and Earth (Fig. 3.1). When used as clocks, the rhythms of nature do not
generate time. A clock does not produce time and it does not consume time; the time displayed is subject to strict international conventions. The idea (concept) of measuring changes (phenomena) is made concrete by the invention of the clock (artifact): this is conception or design, i.e., the materialization of a concept through
the gnomon, sundial, clepsydra, and clock. Consider what Petronius (?–65 AD)
said: … a clock near which a “bucinator” (latin word for a “trumpet player”) warns
us of the flight of the days, and time gone by ([11]: XXV).
Days and hours cannot be measured; it is changes that are measured.
IDEA OF MEASURING CHANGES = MAKING A CLOCK
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Therefore, a consistent definition of the second is
THE SECOND IS A UNIT CORRESPONDING
TO 9,192,631,770 CESIUM CYCLES
This definition of the second does not go against the provisions of the Conferences of 1967 and 1983, including reference to cesium frequency; but its wording has the advantage of not using the word duration. In addition, this definition emphasizes that the international unit of time has no physical existence
In 2011, a British clock reached an accuracy of 2.3 10−16 s, which is an error of 1 s/138 million years. It illustrates the considerable role of high technology and state-of-the-art physics. The leap second between solar time and atomic time requires periodic resynchronization: if time was a physical component of nature, such questions would obviously not arise. The accuracy of measurements is determined by the accuracy of clocks; but the accuracy also depends on the rigor of the definition of the second.
Terrestrial rotations, terrestrial revolutions, and the cesium oscillations, produce observable and measurable cycles, but they do not produce time; even if a misleading field effect suggests the idea of an arrow of time
Both extracts from
The Invention of Time and Space by
Patrice F. Dassonville
If you wish to know about time and clocks I recommend this book. Very detailed in parts but understandably with the contention time does not exist