Talk:Atomic clock
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"The most accurate time scales are moderated by precise astronomical measurements and the insertion or removal of leap seconds. " seems to be wrong since TAI is just as accurate as anything else, in fact, you could argue that it's more "accurate" than UTC since you can use a precise TAI time in the future and know how long from now that is. With UTC you can't.
How did they set the first atomic clock? Did they use astronomical measurements or some other source?
--haavis 12:15, 5 Nov 2004 (UTC)
A: Using astronomical measurements. Does the last paragraph in caesium standard explain it well enough?
--tdunc 8:29,10 May 2007
"When the electrons are attracted back closer by the opposite charge of the nucleus, the electrons wiggle before they settle down in their new location. This moving charge causes the light, which is a wave of alternating electricity and magnetism."
This explaination is unacceptable. The author either needs to elaborate or change it all together, why the electron jumps to a lower level. I have reason to believe it is not because of attraction due to charge (which would be constant), rather the electron emits a photon thus lowering its energy level, which could by coincidence mimick charge attraction but I dont feel its the same concept. If so it needs to work both ways, we cant for instance say a repeling charge is responsible for an electron going into a higher energy level. What is with the word "wiggle" anyway?
- I have fixed the article to avoid this issue. The explanation is simply quantum mechanics. Chapter 9 of Griffith's undergraduate QM textbook has a cogent derivation. Amcfreely 07:01, 16 May 2006 (UTC)
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[edit] Compared to what?
"National standards agencies maintain an accuracy of 10-9 seconds per day"
So I set up my brand new atomic clock, go away for 3 million years, and come back to find out it is off by one second. Compared to what? Another atomic clock? I don't see what else it could be if, by definition, an atomic clock is the standard. --Chauncey27 19:21, 24 December 2005 (UTC)
- Compared to a theoretical ideal. Accuracy of one part in 10-9 is because the clock can be off by as much as half a cycle per second without being noticed. --Carnildo 08:57, 26 December 2005 (UTC)
[edit] Radioactivity?
How radioactive are small atomic clocks? Is it safe to make handheld devices with them?
- A small atomic clock is about as radioactive as any other similarly-sized piece of electronics: that is, slightly less radioactive than the average brick. --Carnildo 09:33, 10 May 2006 (UTC)
[edit] Synchronization
How are Atomic clocks synchronized across the world, or are they not? Do they have to be in the same place to be synchronized off each other sort of thing? Even then how do they set them with such prescison accuracy? —The preceding unsigned comment was added by 90.192.138.193 (talk) 21:02, 22 December 2006 (UTC).
[edit] Mercury Atomic Clock Keeps Time with Record Accuracy
www.nist.gov/public_affairs/releases/mercury_atomic_clock.htm —The preceding unsigned comment was added by 218.102.23.117 (talk) 14:30, 8 January 2007 (UTC).
