Understanding the Concept of Relativity: Unraveling the Confusion

In summary, the conversation is about the concept of relativity, specifically how time and speed are affected by acceleration. The person understands the basic idea of how traveling at a high speed can result in aging less, but is confused about who actually ages less when two objects are moving at different speeds. They also question what happens when meeting another spaceship and how to compare aging in that scenario. The summary concludes with the idea that in relativity, it is always possible to determine who is accelerating and that the concept of time and speed can be different for each observer.
  • #1
Jarfi
384
12
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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  • #2


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.
 
  • #3


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.
 
  • #4


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?
 
  • #5


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?
 
  • #6


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.
 
  • #7
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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1. What is the theory of relativity?

The theory of relativity, developed by Albert Einstein, is a fundamental theory in physics that explains the relationships between space and time. It is divided into two parts: the special theory of relativity, which deals with objects moving at constant speeds, and the general theory of relativity, which deals with objects in accelerated motion.

2. How does the theory of relativity impact our understanding of the universe?

The theory of relativity has had a significant impact on our understanding of the universe. It has helped us to understand the concept of space-time, the bending of light, the behavior of gravity, and the structure of the universe. It has also led to advancements in technology, such as GPS systems, that rely on the principles of relativity.

3. What is the difference between special and general relativity?

The special theory of relativity deals with objects moving at constant speeds, while the general theory of relativity deals with objects in accelerated motion. Special relativity also includes the concept of time dilation, where time moves slower for objects moving at high speeds. General relativity includes the concept of gravity as the curvature of space-time.

4. How can we observe the effects of relativity in our daily lives?

One example of the effects of relativity in our daily lives is the use of GPS systems. These systems rely on the principles of time dilation to accurately calculate positions on Earth. Additionally, the bending of light due to gravity, as predicted by general relativity, has been observed in astronomical phenomena such as gravitational lensing.

5. Is the theory of relativity still considered valid?

Yes, the theory of relativity is still considered valid and has been extensively tested and confirmed by experiments and observations. It is a fundamental theory in physics and has not been disproven or replaced by any other theory. However, scientists continue to study and refine the theory to better understand the workings of the universe.

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