I`ve thought about a special sort of twin paradox.(adsbygoogle = window.adsbygoogle || []).push({});

I know the usual explanation of the twin paradox but give me please the answer to this special case:

Imagine:

A static universe (non-expanding) with a closed geometry and a circumference of one lightyear. The twins start their journey in different direction from their planet (EARTH2) with nearly light speed.

<-------- [TWIN1] [EARTH2] [TWIN2] -------->

Here is my question:

When they will met again after one year on EARTH2 --

which twin is the younger one?

The answer to my question isn`t so easy to give as it seems.

Please think correctly.

You may try this answer:

Twin 1 travels in the system of twin 2 and therefore he ages less because of the time-slowing, conclusion:

he has a different age!

This answer is in contradiction with the principle of relativity!

You may try perhaps this answer:

They both travel the same journey, the conclusion is:

- they both have the same age.

Now you have a serious problem.

Twin 1 had placed 1000 clocks along the circumference of the universe.

The clocks have all the same distance between them - and they also move exactly in the same direction and with the same velocity like twin 1 does.

Imagine now twin 1 synchronises all these moving clocks with his own clock. They all show the same time in the system of twin 1.

Twin 1 says:

I see my twin moves forward from clock1 to clock2 and so on and so I can see that his own slow-down-time conforms to Einsteins theory of relativity.

When my twin finally reaches clock999 to clock1000 and EARTH2 he is finally jounger than me.

Twin 2 makes the same experiment with another set of 1000 clocks.

Twin 2 says:

I see my twin moves forward from clock1 to clock2 and so on and so I can see that his own slow-down-time conforms to Einsteins theory of relativity.

When my twin finally reaches clock999 to clock1000 and EARTH2 he is finally younger than me too!

What are you thinking now?

Who`s one is right?

Please don`t give the usual answer to me I have to search the solution in the general theory of relativity.

That`s no answer at all.

My question is:

Which twin is actually the younger one?

- or have both the same age?

What answer gives us the general theory to this question?

Is there no time-slowing at all?!

Please answer the question.

In my opinion there is no solution to this question.

This paradox shows:

In our universe the special theory of relativity is right. I agree.

But in a closed universe it can`t be right,

conclusion:

we don`t live in a closed universe.

Think you got to know this.

That`s all!

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# Twin paradox in a closed universe

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