Saturday, January 23, 2010

Why worry? Each one of us is carrying an unlicensed nuclear accelerator on his - Wrist?

From ScienceDaily:

The world's most precise clock - on which all time-keeping and navigation systems are based - might be made as small as a wristwatch with a new design proposed by an international team of physicists.

A new class of atomic clocks of at least equivalent accuracy could be made much smaller and simpler by trapping aluminium, gallium, cesium or rubidium atoms in a lattice of laser light operated at a specific "magic" wavelength, according to a new theory put forward by physicists at the University of Nevada, in the US, and the University of New South Wales.

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Ytterbium for Next-Generation Atomic Clocks

Cesium has been the element of choice, thus far, for the most accurate clocks. It is in use in our civilian time standard.

But make way, Cesium:

An experimental atomic clock based on ytterbium atoms is about four times more accurate than it was several years ago, giving it a precision comparable to that of the NIST-F1 cesium fountain clock, the nation's civilian time standard, scientists at the National Institute of Standards and Technology (NIST) report in Physical Review Letters.

This photo shows about 1 million ytterbium atoms illuminated by a blue laser in an experimental atomic clock that holds the atoms in a lattice made of intersecting laser beams. The photo was taken with a digital camera through the window of a vacuum chamber. NIST is studying the possible use of ytterbium atoms in next-generation atomic clocks based on optical frequencies, which could be more stable and accurate than today's best time standards, which are based on microwave frequencies. (Credit: Barber, NIST)

1 million ytterbium atoms illuminated by a blue laser

[via: ScienceDaily]

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Thursday, July 16, 2009

Universal Measurements

Time is, of course, a measurement. As horologists, we are interested in the development of technology used to get the most accurate measurement possible.

I came accross this fascinating article, where...

"These silicon spheres, manufactured by metrologists at Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO) as part of efforts to alleviate dependence on the International Prototype Kilogram, have properties that are as close to truly exact as measurable properties are likely to be for a long time to come: They weigh 1.0000000 kilograms, are smooth to the nearest 0.0000000003 meter, and are round to within 0.000000050 meters. One of them is even monoisotopic." Via boing2.

[via MAKEzine]