Does Earth's Rotation and Revolution Affect Time and Speed?

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Discussion Overview

The discussion revolves around the effects of Earth's rotation and revolution on time and speed, exploring how these movements might influence measurements of time from different frames of reference. The scope includes theoretical considerations and experimental implications related to the speed of light and inertial frames.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants describe Earth's rotation around the sun and its axial spin, proposing that these movements create different speeds at various times of day, specifically at noon and midnight.
  • There is a suggestion that these varying speeds could affect "time speed" as observed from the sun, although the feasibility of such an experiment is questioned.
  • One participant references the Michelson-Morley experiment, noting that despite the expected differences in speed due to Earth's motion, no measurable difference in the speed of light was detected, leading to the conclusion that Earth's motion does not affect time measurements in this context.
  • Another participant acknowledges the complexity introduced by multiple objects and velocities, suggesting that different frames of reference could lead to varying observations of time.
  • Some participants express uncertainty about the explanations provided, indicating a lack of complete understanding while still engaging with the ideas presented.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether Earth's rotation and revolution affect time and speed. While some argue that the effects are negligible based on experimental evidence, others suggest that different frames of reference could lead to varying measurements.

Contextual Notes

The discussion highlights limitations in measuring the effects of Earth's motion on time, including the challenges of detecting differences in the speed of light due to the Earth's varying speeds and the complexities of inertial frames.

pokk
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earth rotates around sun @ R speed, Earth spins on its axis @ S speed. Both R & S are counterclockwise. On the equator @ noon my speed is R-S whereas at midnite its R+S. Q= does this affect the time speed thing?
 
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pokk said:
earth rotates around sun @ R speed, Earth spins on its axis @ S speed. Both R & S are counterclockwise. On the equator @ noon my speed is R-S whereas at midnite its R+S. Q= does this affect the time speed thing?
So your speeds are R+ S vs R- S relative to the sun. So this would affect your "time speed" as observed by someone on the sun. There would be several problems with setting up such an experiment!
 
Because the surface of the Earth is continually accelerating, as you pointed out, noon and midnite approximate two different inertial frames, but in each one, if you measure the round-trip speed of light, you will get the same value.

Prior to this fact becoming known, this is essentially what the famous Michelson-Morley experiment (MMX) was trying to take advantage of, assuming that the speed difference relative to the sun (or the stars or whatever) would be detectable. But note that the speed difference you are talking about has a direction to it, the North-South component of the speed would be the same at noon and at midnite whereas the East-West component would be different. It would have been extremely difficult to make a precise enough measurement of the East-West component of the speed of light at noon and compare that to the same measurement at midnite, twelve hours later. So instead of doing that, they compared the East-West measurement with the North-South measurement, looking only for a difference in the two. But they could never detect any difference, no matter when they did the measurement, at anytime during the day or night nor at anytime during the year. The North-South component always matched the East-West component, as well as all other directions in between.

So this was the first experimental evidence that the answer to your question is "no".
 
ghwellsjr said:
Because the surface of the Earth is continually accelerating, as you pointed out, noon and midnite approximate two different inertial frames, but in each one, if you measure the round-trip speed of light, you will get the same value.

Prior to this fact becoming known, this is essentially what the famous Michelson-Morley experiment (MMX) was trying to take advantage of, assuming that the speed difference relative to the sun (or the stars or whatever) would be detectable. But note that the speed difference you are talking about has a direction to it, the North-South component of the speed would be the same at noon and at midnite whereas the East-West component would be different. It would have been extremely difficult to make a precise enough measurement of the East-West component of the speed of light at noon and compare that to the same measurement at midnite, twelve hours later. So instead of doing that, they compared the East-West measurement with the North-South measurement, looking only for a difference in the two. But they could never detect any difference, no matter when they did the measurement, at anytime during the day or night nor at anytime during the year. The North-South component always matched the East-West component, as well as all other directions in between.

So this was the first experimental evidence that the answer to your question is "no".
thanx & even though i don't understand u i believe u so I'm contemplating your post...thanx
 
The more objects and differences in velocities you add to the expample the more different frame of references there could be to observe you measure time differently.
 
thanx, i get it,thanx, all posts worked
 

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