Understanding the Concept of Relativity: Unraveling the Confusion

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Discussion Overview

The discussion revolves around the concept of relativity, particularly focusing on the implications of time dilation and the effects of acceleration on observers in different frames of reference. Participants explore the complexities of how aging is perceived between observers moving at relativistic speeds and the conditions under which they can determine who is accelerating.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant expresses confusion about who ages less when traveling at relativistic speeds, noting that from their perspective, both they and Earth could be seen as accelerating.
  • Another participant asserts that the Earth does not need to accelerate to reunite with the traveler, emphasizing that acceleration is key to understanding the situation in Special Relativity.
  • A participant questions the implications of meeting another spaceship and whether the aging comparison depends on who accelerated, suggesting that both could perceive themselves as stationary or accelerating.
  • There is a discussion about how to compare aging if two observers meet only once, with one suggesting that they could either look at conditions in a scope or return to meet again.
  • A later reply clarifies that if only one observer is accelerating, they can determine who is moving, but if both are at constant speeds, they could perceive each other differently without a clear resolution on who is traveling.

Areas of Agreement / Disagreement

Participants express differing views on the implications of acceleration and how it affects the perception of time and aging. There is no consensus on the resolution of these questions, and multiple competing perspectives remain throughout the discussion.

Contextual Notes

The discussion highlights the complexities of relativistic effects, including assumptions about acceleration, the conditions under which observers can compare aging, and the implications of meeting other observers in space. These points remain unresolved and depend on specific scenarios.

Jarfi
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I have been learning about relativity, on my own, just checked how it worked, what the main idea was, I understand the concept now, but there is a thing that I can't work out.Say you would take a spaceship from Earth to the nearest galaxy, in 95% lightspeed, Earth sees you as traveling faster, and they see you moving slower, so you should come back, having aged lesss than them, ok at first I got that, but than they talked about how

I could also say, that they were the ones acclerating, I see Earth acclerating from me, and I'm stuck in place, or me at slowing down, So i see them having a slower passage of time, than they should have aged less wen I come back.

Who the hell aged less, I don't get it!
 
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Jarfi said:
I have been learning about relativity, on my own, just checked how it worked, what the main idea was, I understand the concept now, but there is a thing that I can't work out.


Say you would take a spaceship from Earth to the nearest galaxy, in 95% lightspeed, Earth sees you as traveling faster, and they see you moving slower, so you should come back, having aged lesss than them, ok at first I got that, but than they talked about how

I could also say, that they were the ones acclerating, I see Earth acclerating from me, and I'm stuck in place, or me at slowing down, So i see them having a slower passage of time, than they should have aged less wen I come back.

No, you can't say this. You have to fire your engines in order to come to a stop and then return to Earth. The Earth didn't have to do anything in order for to meet up again. In Special Relativity, you can always know who actually accelerated.
 


Janus said:
No, you can't say this. You have to fire your engines in order to come to a stop and then return to Earth. The Earth didn't have to do anything in order for to meet up again. In Special Relativity, you can always know who actually accelerated.

Why did I get that in one seconde because you said it?

god damnit, I got to go get some more sleep.

But thank god, the world is looking pretty clean now, for now.
 


Janus said:
No, you can't say this. You have to fire your engines in order to come to a stop and then return to Earth. The Earth didn't have to do anything in order for to meet up again. In Special Relativity, you can always know who actually accelerated.

Oh but what if you meet a random spaceship passing by, maybe it came from billions of light years away, will it than depend on witch one if us started accelerating? maybe i and my galaxy accelerated to him or maybe he accelerated to me,

Is the thing about reletivity, that it looks to both as if they are stationary or accelerating, but only one is right?
 


Jarfi said:
Oh but what if you meet a random spaceship passing by, maybe it came from billions of light years away, will it than depend on witch one if us started accelerating? maybe i and my galaxy accelerated to him or maybe he accelerated to me,

If you meet only once, how do you compare how much the two of you have aged?
 


jtbell said:
If you meet only once, how do you compare how much the two of you have aged?

You either look at his condition in a scope, or you both return to meet.
 
Jarfi said:
Oh but what if you meet a random spaceship passing by, maybe it came from billions of light years away, will it than depend on witch one if us started accelerating? maybe i and my galaxy accelerated to him or maybe he accelerated to me,

Is the thing about reletivity, that it looks to both as if they are stationary or accelerating, but only one is right?
No, if only one is accelerating, they both can tell which one. But if they both have stopped accelerating so that there remains a speed difference between them and they wait long enough so that they can no longer see any change in the speed of the other one, then from that point on, either one can say the other one is doing all the traveling.

EDIT: It doesn't matter if they ever meet, only that they no longer see the other one as changing their velocity.
 
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