Is Simultaneity Relevant in Intergalactic Communication?

In summary: I don't think it's a question of whether or not we should define it, I think it's a question of whether or not we can. The answer is no, we can't.
  • #1
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Suppose someone from Planet X, In another part of our galaxy, is trying to communicate with the earth. He sends out a message. This is, of course an electromagnetic wave that travels through space with the sepeed of light. Assume that it takes ten years for the message to travel to earth. Twelve years before a radio astronomer on Earth receives the message, the astronomer has received a nobel Prize.

Does this permit us to say that he received the prize before the message was sent from planet X?
 
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  • #2
Where does Planet X come into the picture? btw, an effect cannot precede its cause.
 
  • #3
Sorry about that... they are the same planet...
 
  • #4
How is this a "relativity" question? In fact, how is this even a physics question?

Zz.
 
  • #5
there is no absolute time throughout the universe by which absolute simultaneity can be measured
 
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  • #6
Karma said:
there is no absolute time throughout the universe by which absolute simultaneity can be measured

Well, there sort of is. For example, we often talk about how the CMB was emitted 300,000 years after the Big Bang, and we say that the universe is 13.7 billion years old. While simultaneity is relative, special relativity does not void the concept of time altogether.

By the way I'm fairly certain that the answer is yes, the astronomer received the prize before the message was sent. As someone else said, I'm not sure that this is actually a physics question.
 
  • #7
My initial response still holds true.

Edit: OK, I just reread your question and see that you've changed it. So you might not see how the entire cause-effect thing applies to your situation.
 
  • #8
Karma said:
Suppose someone from Planet X, In another part of our galaxy, is trying to communicate with the earth. He sends out a message. This is, of course an electromagnetic wave that travels through space with the sepeed of light. Assume that it takes ten years for the message to travel to earth. Twelve years before a radio astronomer on Earth receives the message, the astronomer has received a nobel Prize.

Does this permit us to say that he received the prize before the message was sent from planet X?

I still don't see what is "relative" here, or anything to do with relativity. Either you have severely misunderstood "time dilation" in SR, or this has nothing to do with it at all.

Zz.
 
  • #9
I disagree with everyone. First, this is a perfectly valid question, and I think, a profound one. Second, the simple answer is no, there will exist a reference frame where these events happen in reverse order. This is because the two events, the sending of the signal and the awarding of the nobel prize, are related by a "space-like" interval in "Minkowski space". They happen outside each other's "light cone". i.e. they happen at a proper distance of 10 light years apart, and only two years apart in proper time. If they were "time like" then one could say with certainty that one happened before the other. i.e. If they happened one light year apart (proper length) and 10 years apart (proper time), then no "lorenz transformation" would reverse the order.

For more info, google the terms I put in quotes.
 
  • #10
is simulataneity is something we should define? won't it be better if we were confined with oer own world ('within' our time cone) coz' that would shut stupid questions like these!
 

FAQ: Is Simultaneity Relevant in Intergalactic Communication?

What is the "Relativity planet X question"?

The "Relativity planet X question" refers to the hypothetical scenario proposed by physicist Albert Einstein in his theory of general relativity. In this scenario, a planet or celestial body with a very strong gravitational pull, known as "planet X", could potentially alter the orbit of another celestial body like a comet or asteroid, causing it to deviate from its expected path.

Is planet X a real planet?

No, planet X is a hypothetical concept used in Einstein's theory of general relativity. It is not a real planet that has been observed or discovered.

How does the concept of relativity apply to planet X?

Einstein's theory of general relativity states that gravity is not a force between masses, but rather a curvature of space and time caused by the presence of mass. In the "Relativity planet X question", the strong gravitational pull of planet X would cause a distortion in the fabric of space-time, influencing the path of other celestial bodies nearby.

Has planet X been observed or detected?

No, planet X has not been observed or detected. The concept of planet X is purely theoretical and has not been confirmed by any scientific evidence or observations.

Could planet X actually exist and have an impact on our solar system?

While the existence of planet X cannot be ruled out entirely, there is currently no scientific evidence to support its existence. The laws of physics and our understanding of the universe suggest that even if planet X did exist, its impact on our solar system would be minimal.

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