Time travel question: What if you had a Skype conversation with no lag with someone orbiting a gigantic mass in space?

Question

So space time is curved around massive objects. The more massive the object, the more curved space time becomes and thus the passing of time varies...right? So if there was a hypothetical way to link two computers on a Skype conversation, one on earth and one on the shuttle orbiting the mass (let s say it s like 100x bigger than earth so that the time dialation effect is noticeable) and let s say there was no lag between the computers. Quantum entanglement or whatnot. What would that conversation be like? Assuming time on the shuttle is passing at like 1/100th the rate that it is on earth, how would the time dialation be observed? Would they talk in slow motion?

Answer 1

This isn't time travel since nobody is traveling through time. This is a time dilation question.



General Relativity predicts (and it has been empirically shown, finally!) that in a gravitational field time is dilated.



ts = tf sqrt(1- Rs/R)



Where ts is the time for the slow ticking clock a distance R from the center of a mass and tf is a fast ticking clock a sufficiently large distance away from any significant mass, sqrt is the square root function and Rs is the Schwarzschild radius of the mass that the slow ticking clock is around.



This is no more time travel though than if you recorded a live football match and played it back in slow motion.

Answer 2

What if you could travel through time with the power of your imagination? What if you made a device that made all gravity in the universe go away? The what-if you're proposing is like that.



You don't know what quantum entanglement is. You can't communicate faster than light with quantum entanglement. You can't send information with it. It's basically like person A sends 2 envelopes, one to person B and one to person C, and B and C both know that only one of the envelopes contains a hundred dollar bill. Person B opens his envelope and sees there's a 100 dollar bill in it and instantly knows person C doesn't have a hundred dollar bill in his envelope. Did person C SEND any information to person B? Did person B SEND any information to person C? No. There's no message passing between B and C, it's not like person B could MAKE his envelope the one with the hundred dollar bill in it or MAKE it the one without the hundred dollar bill in order to send person C a single bit message of his choosing, and the fact that he can't control which envelope he ends up with is why you can't use this to send information. Quantum entanglement basically is that, except that each envelope is Shrodinger's cat box until one of them is opened, the envelope that the hundred dollar bill is in isn't decided until one of them is opened. But that hardly matters I think. It's really quite unremarkable, actually, I don't know why Einstein called it spooky action at a distance, it's really pretty boring.



Ok. As for the actual INTENT of your question. It doesn't NEED to be with no delay though. Even if the person who is right outside the event horizon of a black hole (and that IS what it would require for a 100-to-1 time ratio, it wouldn't be anywhere near that even orbiting right above the surface of a neutron star) took years for the message to get to Earth because he's light-years away, when it did get here, YES it WOULD be in slow motion. Slowed down in every way. If it was sent with a 100 MHz carrier wave, the person on Earth had better tune his radio to 1 MHz, and the message contents will be slower, if he's talking, his voice will be infrasonic. And whatever you send him would be super fast from his point of view.

Answer 3

Well, a planet 100x the size of the earth would exhibit essentially no noticeable time dilation -- you'd need something a LOT more massive than that -- but I get your point.



The short answer is "yes", they would sound like they're talking in very slow motion. And conversely, everything YOU say would sound very speeded-up to THEM. If you said, "Hey, congratulations! Just checking in, we're all hoping you're having a wonderful time, your Mom misses you. So how's it going?" To them it would sound like, "*blip*" Then, once they slowed that down to where they could understand it and (finally) respond, and then they said "Fine," it would sound to you like a low growl that would go on for over a minute.

Answer 4

Near a very large mass, clocks tick slower. If you were there, where clocks tick slower, the messages you receive from places where clocks tick faster would seem to you to be speeded up, like a record played with the turntable turning too fast.