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A comment on Ways to travel at nearly the speed of light. Parent comment

Re:Ways to travel at nearly the speed of light by smallnamespace on Saturday June 01, 2019 @09:03PM (#20072813)
It's both actually. But that gives an apparent contradiction - how can both observers see that the other party has slower clocks? Who is 'right'?

The answer is that the 'moving' traveler needs to flip the ship around at some point and thrust back towards the starting point. Whoever turns back around will find that it's their clocks that passed more slowly.

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Re:Ways to travel at nearly the speed of light by ctdonath on Saturday June 01, 2019 @10:03PM (#20072991)
And if the universe is spherical?
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Re:Ways to travel at nearly the speed of light by somab on Saturday June 01, 2019 @10:17PM (#20073046)
I think the question you are asking is what if the universe is toroidal. What if you traveled so far you came back around.
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Re:Ways to travel at nearly the speed of light by badosu on Saturday June 01, 2019 @11:34PM (#20073286)
You come back around on a sphere too, e.g. traveling by the equator.
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Re:Ways to travel at nearly the speed of light by somab on Sunday June 02, 2019 @08:35PM (#20079448)
In that case you would be traveling a curved path so there would be acceleration even if your speed remained constant.
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Re:Ways to travel at nearly the speed of light by badosu on Sunday June 02, 2019 @09:59PM (#20079845)
Isnt a torus curved? What's the argument?
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Re:Ways to travel at nearly the speed of light by somab on Tuesday June 04, 2019 @10:48PM (#20101087)
If you use toroidal boundary conditions then you could remain in an inertial reference frame and return back to the same pont.

See https://en.m.wikipedia.org/wiki/Periodic_boundary_conditions

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