« on: 01/02/2016 23:16:35 »
The Earth frame can not both observe the ship traveling at almost the speed of light and take 2000 years to observe the ship arriving.You are using the word observe in 2 different contexts.
What is going on here?
Relativity does not allow for the light travelling back from the destination because it is only considering travel time.
At a speed of almost light the ship will take just over 1000 yrs to reach its destination. The use of the term observer - on earth - should be read as meaning the time taken in the earth reference frame, which is considered to be at rest. If on arrival the ship sets off a bright light the light will take 1000 years to arrive on earth.
I think you are using the word observed to mean watched ie including time for light to get back to our eyes, which is not what was intended.
Edit: sorry MurBob our post crossed. Welcome to the forum, by the way.
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