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Precise atomic clock may redefine time - Device lays the groundwork for a new second.
Nature News ^ | 09 July 2013 | Philip Ball

Posted on 07/09/2013 4:40:57 PM PDT by neverdem

The international definition of a second of time could be heading for a change, thanks to researchers who have demonstrated that an advanced type of ‘atomic clock’ has the degree of precision and stability needed to provide a new standard.

Jérôme Lodewyck of the Paris Observatory and his colleagues have shown that two so-called optical lattice clocks (OLCs) can remain as perfectly in step as experimental precision can establish1. They say that this test of consistency is essential if OLCs are to be used to redefine the second, which is currently defined according to a different type of atomic clock.

Christopher Oates, a specialist in atomic-clock time standards at the National Institute of Standards and Technology (NIST) in Boulder, Colorado, says that this is “very beautiful and careful work, which gives grounds for confidence in the optical lattice clock and in optical clocks generally”.

Since 1967, the second has been defined as the duration of 9,192,631,770 oscillations of the microwave radiation absorbed or emitted when a caesium atom jumps between two particular energy states.

The most accurate way to measure this frequency at present is in an atomic fountain, in which a laser beam propels atoms in gasous caesium upwards. Emission from the atoms is probed as they pass twice through a microwave beam – once on the way up, and once as they fall back down under gravity.

Caesium atomic-fountain clocks are used to set national time standards at NIST, at the Paris Observatory and elsewhere.

The caesium fountain clock has an accuracy of about three parts in 10 quadrillion (3 × 10−16). This means that it will keep time to within one second over 100 million years. But some newer atomic clocks can do even better. Monitoring emission from individual ionized atoms trapped by an electromagnetic field can...

(Excerpt) Read more at nature.com ...


TOPICS: Science
KEYWORDS: atomicclock; physics

1 posted on 07/09/2013 4:40:57 PM PDT by neverdem
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To: neverdem

Wait a damned minute, or .. a.. second... I just reset my clocks for daylight saving time.. I won’t do it again until New Years Eve, if history repeats itself... :)


2 posted on 07/09/2013 4:46:50 PM PDT by carlo3b (Speechless in Sugar Land)
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To: neverdem

My watch is running slow!!


3 posted on 07/09/2013 4:47:12 PM PDT by Forrestfire (("To educate a man in mind and not in morals is to educate a menace to society." Theodore Roosevelt))
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To: neverdem

I will spend the rest of the day trying to determine the best possible use for that extra second.


4 posted on 07/09/2013 4:49:24 PM PDT by Gator113
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To: neverdem
This means that it will keep time to within one second over 100 million years.

That's good enough for me! I call and sync my wristwatch with the Naval Observatory's clock once in a while.

5 posted on 07/09/2013 4:49:30 PM PDT by FoxInSocks ("Hope is not a course of action." -- M. O'Neal, USMC)
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To: carlo3b

If I were a wind-up clock, I would be really ticked


6 posted on 07/09/2013 4:53:16 PM PDT by chajin ("There is no other name under heaven given among people by which we must be saved." Acts 4:12)
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To: neverdem; a fool in paradise

What a relief! You’ll never again miss your flight, your doctor or IRS appointment!


7 posted on 07/09/2013 4:54:14 PM PDT by Revolting cat! (Bad things are wrong! Ice cream is delicious!)
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To: chajin

What are you tocking about?


8 posted on 07/09/2013 4:55:24 PM PDT by A Formerly Proud Canadian (I once was lost but now I'm found; blind but now I see.)
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To: neverdem

Just think (and appreciate) of the precision this discovery is sure to add to the records the NSA has on us all!


9 posted on 07/09/2013 4:56:44 PM PDT by Revolting cat! (Bad things are wrong! Ice cream is delicious!)
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To: chajin

LOL.. great one.. :)


10 posted on 07/09/2013 4:59:57 PM PDT by carlo3b (Speechless in Sugar Land)
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To: chajin

Good one. I have to hand to you.


11 posted on 07/09/2013 5:04:38 PM PDT by Ray76 (Do you reject Obama? And all his works? And all his empty promises?)
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To: neverdem

Just a quibble. But the title of the article is really misleading. Time has not been “redefined” nor is there a “new second.”

All the clock does is demonstrate the POSSIBILITY of measuring a second more accurately than existing clocks.


12 posted on 07/09/2013 5:24:27 PM PDT by ModelBreaker
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To: FoxInSocks
USN Observatory Master Clock

13 posted on 07/09/2013 6:10:19 PM PDT by kitchen (Make plans and prepare. You'll never have trouble if you're ready for it. - TR)
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To: neverdem

It’s about time.


14 posted on 07/09/2013 6:25:30 PM PDT by UnwashedPeasant
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To: neverdem

New definiion:

One-Mississippi...two-Mississippi


15 posted on 07/09/2013 6:40:05 PM PDT by Mike Darancette (Fight the culture of nothing.)
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To: ModelBreaker

Title are rarely written by the author, and title-writers rarely read much of the article. They also have little interest in reflecting the article accurately. Their goal is to get you to read the article based on the headline. Nothing more. Journalism today is a capitalist enterprise, and they are focused on ratings and ad revenue far more than accuracy, information, or fairness.


16 posted on 07/09/2013 6:58:16 PM PDT by Teacher317 (The public is being manipulated to fleece the taxpayer. That is the real industry in Washington.)
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To: kitchen

Well, yes, I could do that, but who knows how many switches and routers and servers and systems that signal is running through. I always figured a [landline] phone call might be more accurate — every second counts, right?! ;-)


17 posted on 07/09/2013 8:43:15 PM PDT by FoxInSocks ("Hope is not a course of action." -- M. O'Neal, USMC)
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To: Revolting cat!

18 posted on 07/10/2013 9:44:03 AM PDT by a fool in paradise (America 2013 - STUCK ON STUPID)
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