# Question about clocks (1 Viewer)

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#### ValenceE

Hello to all,

Could someone give me a link that would point me towards a description of the inner workings of the famous clocks that are part of all discussions and experiments dealing with the relativity of time. What kind of clocks are those ?

Thank you,

VE

#### JesseM

Any kind of physical clocks whatsoever, according to our current knowledge.

#### robert Ihnot

I thought most of them were sand clocks.

#### notknowing

Hello to all,

Could someone give me a link that would point me towards a description of the inner workings of the famous clocks that are part of all discussions and experiments dealing with the relativity of time. What kind of clocks are those ?

Thank you,

VE
Hi, this is a very interesting question. One could go a little bit deeper into this and ask what physical constants are necessarily involved. If one has for instance a simple resonant L-C circuit, then such a clock would involve the dielectric permittivity and magnetic permeability of the vacuum. Other clocks could involve Plancks constant, the charge of an electron, ... (for instance in the Rydberg frequency).
It would be interesting to know what constants are minimally required.
Could someone for instance make a clock in which the frequency is only based on the magnetic permeability of the vacuum ?

#### notknowing

Hi, this is a very interesting question. One could go a little bit deeper into this and ask what physical constants are necessarily involved. If one has for instance a simple resonant L-C circuit, then such a clock would involve the dielectric permittivity and magnetic permeability of the vacuum. Other clocks could involve Plancks constant, the charge of an electron, ... (for instance in the Rydberg frequency).
It would be interesting to know what constants are minimally required.
Could someone for instance make a clock in which the frequency is only based on the magnetic permeability of the vacuum ?
I just realised that the answer to my last question is definitely NO. In fact one just has to look for all combinations of "physical constants" which result in a dimension of time.

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