I Time Dilation Paradox: Geosynchronous Satellites

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Time dilation in geosynchronous satellites presents a paradox due to competing effects: gravitational time dilation causes time to move faster at higher altitudes, while kinematic time dilation slows time for objects moving at high speeds. The gravitational effect dominates, meaning that despite the satellite's high speed, its time appears to move faster relative to an observer on Earth. It is essential to understand that time is experienced consistently at one second per second, but appears different based on relative motion and gravitational depth. The discussion highlights the complexity of time perception in different frames of reference. Ultimately, the apparent paradox is resolved by recognizing the interplay of these relativistic effects.
InquiringMind
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Time moves faster when higher above the earth. Time move slower the faster you are moving. A geosynchronous satellite has to be very high to be geosynchronous so it's time should be fast, but it also has to be orbiting the earth extremely fast to keep up with a geosynchronous position, so it's time should be slow. This seems like a paradox to me.
 
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InquiringMind said:
This seems like a paradox to me.
Why? It's just two competing effects.
 
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InquiringMind said:
A geosynchronous satellite has to be very high to be geosynchronous so it's time should be fast
In that case the gravitational effect wins over the kinematic effect

Time_Dilation_vs_Orbital_Height.png
 
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InquiringMind said:
Time moves faster when higher above the earth. Time move slower the faster you are moving
Just to be sure you are clear, neither one of these statements is true as an absolute statement. What you have left out is "relative to <something>". That is, your time ALWAYS moves at one second per second no matter where you are in a gravity well or how fast you are moving relative to something else.

Time APPEARS, to a different observer, to move a differing rates relative to that observer's rate, depending on relative depth in a gravity well and relative speed.
 
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InquiringMind said:
Time moves faster when higher above the earth. Time move slower the faster you are moving. A geosynchronous satellite has to be very high to be geosynchronous so it's time should be fast, but it also has to be orbiting the earth extremely fast to keep up with a geosynchronous position, so it's time should be slow. This seems like a paradox to me.
If you eat too much food, you put on weight. If you exercise a lot, you lose weight. If you eat a lot and exercise a lot you should put on weight and you should lose weight. Is that a paradox too?
 
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InquiringMind said:
it also has to be orbiting the earth extremely fast to keep up with a geosynchronous position
Free-fall orbital speed decreases with altitude.
 
The Poynting vector is a definition, that is supposed to represent the energy flow at each point. Unfortunately, the only observable effect caused by the Poynting vector is through the energy variation in a volume subject to an energy flux through its surface, that is, the Poynting theorem. As a curl could be added to the Poynting vector without changing the Poynting theorem, it can not be decided by EM only that this should be the actual flow of energy at each point. Feynman, commenting...

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