Orbiting Time Dilation: Who is Younger?

[g_sanguinetti]

Two ships orbit a planet in opposite directions. Each time they pass each other who is younger?

 

[Mentz114]

Is the planet rotating ? If so, how are the orbits aligned wrt to the poles ?

 

[g_sanguinetti]

The planet is not rotating.

 

[George Jones]

Assuming the planet is in inertial frame, equal times elapse on the ships between meetings.

 

[g_sanguinetti]

Doesn't special relativity predict time dilation between the two ships since there is a relative velocity between them?

 

[George Jones]

Doesn't special relativity predict time dilation between the two ships since there is a relative velocity between them?

No,; this a common misconception.

 

[Mentz114]

Doesn't special relativity predict time dilation between the two ships since there is a relative velocity between them?

They may see each others clocks running differently, but the ageing, or elapsed time will be the same for both when they meet.

 

[g_sanguinetti]

No,; this a common misconception.

So then, when does and when does not relativity apply?

 

[g_sanguinetti]

They may see each others clocks running differently, but the ageing, or elapsed time will be the same for both when they meet.

What do they see?

 

[Mentz114]

What do they see?

That is a difficult question to answer. I've worked out the time-dilation between radially separated observers here -

https://www.physicsforums.com/showthread.php?t=244511

I'll try and do the sums for orbiting observers at some time. Watch this space.

M