Time Measurement: Vibration of Photon vs Atom

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    Measurement Time
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Discussion Overview

The discussion revolves around the concept of measuring time, specifically comparing the vibrations of photons and atoms. Participants explore the implications of relativity on time measurement and propose alternative methods for defining time intervals based on photon vibrations.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that since time is not absolute due to relativity, it may be more appropriate to measure time using the vibration of photons rather than atoms.
  • One participant questions which specific photon should be chosen as a standard for time measurement, highlighting the challenges of defining colors and wavelengths in relation to atomic standards.
  • Another viewpoint proposes measuring time using the period of electromagnetic oscillations, emphasizing the need to clarify whether proper time or coordinate time is being measured.
  • It is noted that measuring time with photons requires a known fixed wavelength to determine frequency, and that the Doppler effect complicates this measurement when in motion relative to the source.
  • A suggestion is made to select a photon from the cosmic microwave background (CMB) for cosmological time measurement, linking this to broader implications about the universe's nature.
  • Some participants express skepticism about using measurements that can change, such as those affected by the Doppler effect, while others clarify that no Doppler effect occurs if one is stationary relative to the source.

Areas of Agreement / Disagreement

Participants express differing views on the appropriateness of using photon vibrations for time measurement, with no consensus reached on the best approach or standard to use. The discussion remains unresolved regarding the implications of relativity and the practicality of photon-based time measurement.

Contextual Notes

Participants highlight limitations in defining standards for photon wavelengths and the effects of motion on frequency measurements. The discussion reflects uncertainty about the implications of using photons versus atoms in time measurement.

bassplayer142
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After I realized that relativity slowed and speeds up time relative to the frame of reference I realized that time is not absolute. Why would we continue to measure time as the vibration of an atom. Wouldn't we start measuring time by the vibration of a photon? Since a photon is absolute no matter where in the universe it is and it stays constant for that wavelength.
 
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bassplayer142 said:
After I realized that relativity slowed and speeds up time relative to the frame of reference I realized that time is not absolute. Why would we continue to measure time as the vibration of an atom. Wouldn't we start measuring time by the vibration of a photon? Since a photon is absolute no matter where in the universe it is and it stays constant for that wavelength.

which photon would you choose as a standard for a unit of time?

be very careful answering that. if you say "photons of blue visable light" then i would ask how you define blue? if blue photons are the photons that make it through some standardized blue filter, then you're back to defining this in terms of the atoms of some material.
 
measuring time

bassplayer142 said:
After I realized that relativity slowed and speeds up time relative to the frame of reference I realized that time is not absolute. Why would we continue to measure time as the vibration of an atom. Wouldn't we start measuring time by the vibration of a photon? Since a photon is absolute no matter where in the universe it is and it stays constant for that wavelength.

Why not measure time using as an unit the period of the electromagnetic oscillations taking place in the electromagnetic wave in which we are immersed? Besides that we should now which kind of time interval we measure: proper time or coordinate time.
 
To measure time, you need photons of known fixed wavelength, so that you know the frequency. If you are moving in reference to the source, that changes the frequency (doppler effect), but that's not a problem in atomic clocks. So you use a specific atomic vibration, with a specific energy, to generate the photons of fixed frequency.
 
Last edited:
rbj said:
which photon would you choose as a standard for a unit of time?
To measure cosmological time:

Select a photon sampled from the peak emission intensity of the CMB corrected for the Earth's dipole movement.

Then the universe woul be eternal, and if c is defined constant and used to measure radar distance, the universe would also be static, as in the Jordan conformal frame of http://en.wikipedia.org/wiki/Self-creation_cosmology .

Garth
 
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I guess your right about the doppler effect. It just doesn't seem right to measure time with something that changes.
 
bassplayer142 said:
I guess your right about the doppler effect. It just doesn't seem right to measure time with something that changes.

You don't get any Doppler effect if you are not moving wrt the source. In metrology, your clock is supposed to be infinitely small and to lie at rest no farther away from your elbow. So, no Doppler effect, of ny sort.
 

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