Questions tagged [atomic-clocks]
Use for atomic clocks - not any other type of clock.
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Allan deviation power expansion
In the 'Hand Book of Frequency Analysis' S3.2, by W.J Riley the frequency stability of an oscillator is expressed as a combination of power-law noises of the form $S(f)\propto f^\alpha$, where $f$ is ...
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Connection between quantum non demolition measurement and the Heisenberg limit in metrology
Quantum non demolition measurements are those that do not feed back action noise into the measured observable. For discrete systems, this leads to the somewhat trivial case of where the observable (...
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What is stopping optical clocks from redefining the second?
Optical clocks, based on optical transitions either in cold atomic lattices or trapped ions, have been shown to up to one million times better accuracy/precision compared to the cesium microwave ...
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Defining the second by an alien civilization [closed]
(The above question could be phrased better, so feel free to suggest.)
Like many, I was imprecisely told that the second is 9192631770 oscillations of caesium valence electron (or smth along those ...
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How to prove that time slow down on all type of clocks? [duplicate]
I read about time dilation and how to prove time dilation existence with light clock.
But how to prove that time slow down on all other type of clocks (biological, mechanical, digital, electric, ...
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Conceptual relations between tick indications of a clock and corresponding tick-response indications of a receiver observing that clock
Descriptions of setups and findings involving clocks can also involve distinct observers (in the following a.k.a. receivers) which (in general) perceived, and possibly then analyze, relevant signals ...
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How to determine whether an atomic clock had "ticked at the Moon's natural pace"? (Nature 614, 13-14 (2023))
The recent news article "What time is it on the Moon? Researchers plan to build a lunar clock", Nature 614, 13-14 (2023) claims that
"Clocks on Earth and the Moon naturally tick at ...
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Why does a transition between 2 $s$-orbitals work for cesium's clock transition?
I have a small question about the cesium's clock transition. According to the information on the Wiki: https://en.wikipedia.org/wiki/Caesium_standard, the chosen transitions are two hyperfine ground ...
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If we had just invented the first clock, and we only had a calendar system, how would we set the time of day for the first time?
I've noticed there are extensive answers on this website about the accuracy of atomic clocks and how they reference the time between each other with the average of time between each other, but I ...
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Why do atomic clocks occasionally fail?
Atomic clocks like the NIST-F1 are extremely accurate yet they can lose a second in a time frame of several million years. Why aren't atomic clocks 100% accurate?
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Why H/Cs/I atomic clocks are more complicated than Rb?
It is known that low-cost commercial Rb atomic clocks are fairly simple in construction: gas cell is probed by a light source and excited by RF around 6.8Ghz. When frequency is right - we see decrease ...
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Solution of Two-Level Atom Equation
I am reading Foot's book. It has the following equations for a two-level atom interacting with light.
$$\begin{align}
i\dot{c}_1&=c_2e^{i(\omega-\omega_0)t}\frac{\Omega}{2}, \\
i\dot{c}_2&...
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Measuring time dilation (due to velocity) with an atomic clock
Let there be a system in uniform motion to us at 36,000 mph, and let it have a clock onboard sending us signals as it ticks. Let us have our own clock, and let us account for variations due to that ...
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Why Rubidium-87 instead of Rubidium-85 for Atomic Clocks?
The traditional Rubidium isotope of choice for atomic clocks is Rubidium-87, although I have found papers describing clocks built around Rubidium-85. I cannot readily find any references for why 87 is ...
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Evolution operator of a two-level system in atomic clocks
I have a few questions concerning equation (6) from this (http://arxiv.org/abs/1610.02537) paper from Weinberg in which he describes the time evolution of a two level system e.g. a Cs atom in an ...
