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Atomic Clocks Make a Quantum Leap in Accuracy

engineering.com

11–20 of 45 posts

Re: Atomic Clocks Make a Quantum Leap in Accuracy

#12

The coolest part it that it improves both stability and accuracy. Cesium is often touted as a good clock but it only has good accuracy. The short-term stability has more noise than something like a Rubidium clock that is very stable on the short-term but inaccurate(relative to cesium anyway) on the long term. This is cool because it is the best in both dimensions.

True! People use Rubidium clocks only because they are inexpensive. I don't think scientists working in expensive labs rely on Rubidium clocks.

Re: Atomic Clocks Make a Quantum Leap in Accuracy

#13
post #4

Hate to be that guy when it comes to being pedantic about headlines, but wouldn't a `quantum leap` in accuracy be rather un-noteworthy?

Quantum leap refers to a sudden increase in something. Given that this clock is 50% more precise than the previous record holder, I think it qualifies to be called a 'quantum leap'. So even if you are pedantic about headlines, it should still make sense. Don't you think so?

Re: Atomic Clocks Make a Quantum Leap in Accuracy

#15
post #9

This could be the basis of a future tricorder or Star Trek-like sensor array. Three ultra-sensitive clocks in an array should be able to infer mass and motion both for the unit and objects in the local area indirectly. Relativistic effects are minuscule, but not non-existent. Extremely-tuned clocks would have some pretty cool capabilities.

One thing I've spent some time thinking about is whether it would be possible to use atomic clocks to get a better measurement of the gravitational constant G. (G is by far the most poorly known of all the fundamental physical constants.) The idea would be to build a sphere whose mass is very precisely known and place one clock near the mass and one clock far away. By measuring the gravitational time dilation you cou…

Good point! The research group is still working on refining their system. So may be they will have another breakthrough in a year or two, you never know!

Re: Atomic Clocks Make a Quantum Leap in Accuracy

#16
post #4

Hate to be that guy when it comes to being pedantic about headlines, but wouldn't a `quantum leap` in accuracy be rather un-noteworthy?

Quantum leap refers to a sudden increase in something. Given that this clock is 50% more precise than the previous record holder, I think it qualifies to be called a 'quantum leap'. So even if you are pedantic about headlines, it should still make sense. Don't you think so?

This might clarify what he meant: http://www.smbc-comics.com/?id=2628

Re: Atomic Clocks Make a Quantum Leap in Accuracy

#18
post #10

In a vacuum, you could get GPS accuracy down to 700 nanometers with clocks that accurate [1]. If only that pesky atmosphere didn't get in the way! [1]: http://www.wolframalpha.com/input/?i=%281+second+%2F430+tril...

There are also other problems than atmosphere.

http://eu.mio.com/en_gb/global-positioning-system_gps-accura...

Re: Atomic Clocks Make a Quantum Leap in Accuracy

#19

The coolest part it that it improves both stability and accuracy. Cesium is often touted as a good clock but it only has good accuracy. The short-term stability has more noise than something like a Rubidium clock that is very stable on the short-term but inaccurate(relative to cesium anyway) on the long term. This is cool because it is the best in both dimensions.

True! People use Rubidium clocks only because they are inexpensive. I don't think scientists working in expensive labs rely on Rubidium clocks.

Some Rubidium clocks require very little power (700mW or less). This makes them ideal for under water applications where short term accuracy isn't an issue because the SONAR data transmission is going to be a mess anyway, and they provide much better long term stability than a crystal oscillator.

Re: Atomic Clocks Make a Quantum Leap in Accuracy

#20
Ask: Such synchronous clocks possible?

Special and general relativity steam-roll over synched digit accuracy, at introducing any object's mass, any object's displacement.

Not gain or lose over five billion years?

How many digits this time?

Tides, quakes, rain on the roof, defeat the possibility of unbounded synched accuracy.

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