Einstein's Twin Paradox: Age Difference on a Rocket at the Speed of Light

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Discussion Overview

The discussion revolves around the Twin Paradox, specifically examining the age difference between twins when one travels on a rocket at the speed of light and then returns to Earth. The conversation touches on the implications of relativistic effects on aging and the mechanics of space travel.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant suggests a scenario where a rocket accelerates to the speed of light but then runs out of fuel, questioning the resulting age difference between the twin on the rocket and the one on Earth.
  • Another participant challenges the coherence of the initial scenario, arguing that a rocket cannot slow down in space without firing its engines, implying the need for clarification on the mechanics involved.
  • A subsequent reply proposes a modified scenario where engines are used to slow down the rocket, indicating a willingness to explore the implications of this adjustment.
  • One participant mentions that, according to their understanding, time does not pass for an object traveling at the speed of light, suggesting that the traveling twin would not age while the twin on Earth continues to age normally.
  • Another participant questions the clarity of the original question, asking whether the inquiry is for personal understanding or merely a brain teaser, which may not be appropriate for the forum.

Areas of Agreement / Disagreement

Participants express differing views on the mechanics of the rocket's motion and the implications for aging, indicating that there is no consensus on the scenario or its interpretation.

Contextual Notes

There are unresolved assumptions regarding the feasibility of traveling at the speed of light and the mechanics of aging in different frames of reference. The discussion also lacks clarity on the specific conditions under which the age difference is being evaluated.

General_Relativity19
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say the rocket had a engine, which produced to get the rocket to go at the speed of light but then it ran out of fuel and the rocket would slow down. what would be the age difference between them? say both were 24 one on Earth and one on return journey from a nearby star system.
 
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General_Relativity19 said:
say the rocket had a engine, which produced to get the rocket to go at the speed of light but then it ran out of fuel and the rocket would slow down. what would be the age difference between them? say both were 24 one on Earth and one on return journey from a nearby star system.
That isn't even close to being a coherent thought. Could you try again please? The one part that made any sense - the part about the rocket slowing down - is wrong. Rockets do not slow down in space without engines firing to slow them down.
 
russ_watters said:
That isn't even close to being a coherent thought. Could you try again please? The one part that made any sense - the part about the rocket slowing down - is wrong. Rockets do not slow down in space without engines firing to slow them down.


ok so what if the there were engines that fired to slow them down?
 
Well, your question is kind of sketchy, but if I am reading it right...
since light has no notion of time (time freezes when you are traveling the speed of light), the spaceship in space would be equal to 24 (it would remain unchanged, and the spaceship on Earth would have continued aging at a normal rate...
 
cheers mark
 
Does the spaceman come back to Earth to compare ages ? You don't specify which frame you are measuring in ? Are you asking because you want to know...or because you want to see what other people know ? In other words, is this a doubt or a brain teaser ? The latter does not belong here.
 

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