Does time move faster while measured from space or from earth?

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Time is measured differently on Earth compared to space due to the effects of gravitational time dilation and relative motion. Atomic clocks in space will register the same number of vibrations per second, but observers on Earth will perceive the space clock as ticking faster due to gravitational effects. GPS satellites must account for these time discrepancies to maintain accurate positioning. The discussion highlights that the depth in the gravitational potential field is crucial, as it influences how time is experienced differently in various gravitational strengths. Overall, the complexities of general relativity and special relativity play significant roles in how time is perceived in different locations.
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If you were to have an atomic clock, would it registered that time is moving faster while earth-bound or while orbiting in a satellite?

Also, most atomic clocks measure the amount cesium vibrates a second, which is 9,192,631,770. If time moved 'slower' would this number drop, or would it increase? My guess is increase but I just want to be sure.
 
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Rorkster2 said:
If you were to have an atomic clock, would it registered that time is moving faster while earth-bound or while orbiting in a satellite?

Well, first, the term's a bit misleading. But the stronger gravitational field would cause an orbiting observer to see a person on Earth's clock moving more slowly. (I imagine a person on Earth would see an orbiting observer's clock moving more quickly, but I have no evidence to back this.)

Also, most atomic clocks measure the amount cesium vibrates a second, which is 9,192,631,770. If time moved 'slower' would this number drop, or would it increase? My guess is increase but I just want to be sure.

What do you mean? An atomic clock, regardless of gravitational field, for any local observers, measures the same number of vibrations per second. Now, if the two are moving relative to each other, then SR kicks in, but neither's truly moving more slowly. When we finally get to GR, which is in a stronger gravitational field? The clock or the observer?
 
Whovian said:
What do you mean? An atomic clock, regardless of gravitational field, for any local observers, measures the same number of vibrations per second.
Not true. Time does move at a slightly different pace in space then on earth. And I know the answere is known to scientists. GPS satellites and other perscise communications from Earth to space need to take this 'time speed shift' into account or else everything would be off and GPS would not work in the manner intended. So the answere is somewhere, I am just hoping someone here knows it.
 
Rorkster2 said:
Not true. Time does move at a slightly different pace in space then on earth. And I know the answere is known to scientists. GPS satellites and other perscise communications from Earth to space need to take this 'time speed shift' into account or else everything would be off and GPS would not work in the manner intended. So the answere is somewhere, I am just hoping someone here knows it.

True. However, note that I stated local observers. Nearby observers will still see cesium atoms have 9,192,631,770 vibrations/sec. Observers in stronger gravitational fields than the atoms should see more, weaker less.
 
Rorkster2 said:
I answered my own question upon further research. (http://en.wikipedia.org/wiki/Gravitational_time_dilation) time passes slower in space.

Define what you mean. Are you saying that observers on Earth will see observers in space have slower clocks? Far as I can tell, this is the exact opposite of what happens.
 
Whovian said:
Define what you mean. Are you saying that observers on Earth will see observers in space have slower clocks? Far as I can tell, this is the exact opposite of what happens.

I mean people in space will have a slower clock that registers a slightly less amount of vibrations per second then an atomic clock on the Earth's surface due to the presents of more gravity.
 
Rorkster2 said:
I mean people in space will have a slower clock that registers a slightly less amount of vibrations per second then an atomic clock on the Earth's surface due to the presents of more gravity.
A ground clock sees a space clock as gravitationally blue shifted. A space clock sees a ground clock as gravitationally red shifted. So, if anything, both agree that the space clock is faster.
 
Rorkster2 said:
I mean people in space will have a slower clock that registers a slightly less amount of vibrations per second then an atomic clock on the Earth's surface due to the presents of more gravity.
If people in space observer their clock in space, it will always have 9,192,631,770 oscillations per second. This is the definition of a second! If they observe a proper clock on earth, they will see less oscillations there, per second on their own clock.

With high orbits, general relativity dominates, and the effect is asymmetric - observers on Earth will see that the space clock ticks more than 9,192,631,770 times per Earth second.

The GPS satellites operate with a frequency of 10.22999999543 MHz (in their own frame), and we on Earth observe the signals with a frequency of 10.23 MHz - more ticks per second.
 
  • #10
[what DaleSpam said]

Note that it is not the gravitational field strength that matters, per se. It is the depth in the gravitational potential field. A weak field that extends over a long distance will have the same effect in this respect as a strong field that extends over a short distance.

Note also that for orbitting clocks one needs to account for the relative velocity between a clock on the surface and one orbitting above. The orbitting clock will run slow because of its motion. [From an SR point of view, the orbitting clock is not at rest in an inertial frame]

Whether the "GR" effect of the low clock running slow or the "SR" effect of the rapidly moving clock running slow will dominate depends on whether the craft is in a high fast orbit or low slow one.
 
  • #11
Thanks everyone this has been a big help
 
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