What Happens in the Reverse Twins Paradox with Accelerated Motion?

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Discussion Overview

The discussion revolves around the Reverse Twins Paradox, specifically examining the scenario where two twins start in ships moving at relativistic speeds, with one twin traveling to Earth and back while the other remains in uniform motion. The focus is on determining which twin ends up older, considering the effects of acceleration and changes in direction.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant questions the outcome of the Reverse Twins Paradox, asking who ends up older when one twin travels to Earth and back while the other maintains uniform motion.
  • Another participant suggests that the twin who changes direction and accelerates four times will be the younger one, although this claim is later corrected.
  • A different participant introduces a concept related to the worldlines of observers, stating that the observer with a longer Euclidean length between two events will have a shorter Lorentzian length and thus shorter proper time, implying they remain younger.
  • A subsequent post corrects the earlier claim, clarifying that the twin who changed direction and accelerated is indeed the younger one.

Areas of Agreement / Disagreement

Participants express differing views on the implications of acceleration in the Reverse Twins Paradox, and the discussion remains unresolved regarding the definitive outcome of which twin is older.

Contextual Notes

There are missing assumptions regarding the specifics of acceleration and the definitions of proper time in the context of relativistic motion, which may affect the conclusions drawn.

Austin0
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Reverse Twins paradox ?

This may have come up before but I haven't seen it and don't know the answer.

What if the twins started out in two ships moving together at relativistically significant velocity relative to earth. One of the twins then simply goes to Earth and back while the other maintains unform motion.

In this situation who ends up older?
 
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Austin0 said:
This may have come up before but I haven't seen it and don't know the answer.

What if the twins started out in two ships moving together at relativistically significant velocity relative to earth. One of the twins then simply goes to Earth and back while the other maintains unform motion.

In this situation who ends up older?
The one that changed direction and accelerated four times.
 
Last edited:


for the worldlines of two observers who meet up at two different events, the one which has a longer Euclidean length between these two events, will have a shorter Lorentzian length, thereby a shorter proper time and consequently the corresponding observer remains younger. draw a diagram.
 


MeJennifer said:
The one that changed direction and accelerated four times.
Oops, I mean to say that the one that changed direction and accelerated four times is the younger not the older one. My apologies.
 

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