Altering the circadian clock adapts barley to short growing seasons

To ensure that plants flower at the right time of year, they possess an internal clock that enables them to measure the amount of daylight during a day. In a study published in the journal Plant Physiology, biologists from ...

Quantum dark states lead to an advantage in noise reduction

While atomic clocks are already the most precise timekeeping devices in the universe, physicists are working hard to improve their accuracy even further. One way is by leveraging spin-squeezed states in clock atoms.

Protecting rice plants from heat when it attacks at nighttime

Rice (Oryza sativa L.) is the staple food for more than half of the world's population. Based on mathematical modeling, worldwide cereal production is estimated to have a loss of 6%–7% yield per 1°C increase in seasonal ...

Dipole-dipole interactions: Observing a new clock systematic shift

In a new study published in Science today, JILA and NIST (National Institute of Standards and Technology) Fellow Jun Ye and his research team have taken a significant step in understanding the intricate and collective light-atom ...

The tale of two clocks: Advancing the precision of timekeeping

Historically, JILA (a joint institute established by the National Institute of Standards and Technology [NIST] and the University of Colorado Boulder) has been a world leader in precision timekeeping using optical atomic ...

Image: Micro-world within an atomic clock

What looks like an aerial shot of an alien landscape is actually a scanning electron microscope view of a test glass surface, acquired as part of a project to improve the lifetime of spaceborne atomic clocks, found at the ...

Neanderthals may have been morning people, says new study

A new research paper finds that genetic material from Neanderthal ancestors may have contributed to the propensity of some people today to be "early risers," the sort of people who are more comfortable getting up and going ...

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Clock

A clock is an instrument used to indicate, keep, and co-ordinate time. The word clock is derived ultimately (via Dutch, Northern French, and Medieval Latin) from the Celtic words clagan and clocca meaning "bell". A silent instrument missing such a mechanism has traditionally been known as a timepiece. In general usage today a "clock" refers to any device for measuring and displaying the time. Watches and other timepieces that can be carried on one's person are often distinguished from clocks.

The clock is one of the oldest human inventions, meeting the need to consistently measure intervals of time shorter than the natural units: the day; the lunar month; and the year. Devices operating on several different physical processes have been used over the millennia, culminating in the clocks of today.

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