I’m asking this because there is a scifi book I’m reading, and in the book there’s a scene where someone is communicating with a person in a spacecraft moving at lightspeed. I know their ability to communicate would probably not be possible, but let’s just put that aside for a second. Hypothetically, if you could communicate with someone moving lightspeed, would the time dilation make it so that they would appear to be moving and speaking very slowly relative to you?
That’s interesting, thanks for explaining.
I guess I’m just confused as to how you can have situations where someone ages faster than another due to time dilation. That doesn’t seem to be a symmetrical outcome. Like this scene in Interstellar (which, as I understand it, is scientifically accurate). In this scene Matthew McConaughey goes away for 3 hours and finds that, due to time dilation, his kids have aged 23 years. There doesn’t seem to be a symmetry here. Because Matthew McConaughey aged slower than his children, it would be weird if, from his point of view, his kid’s clocks were ticking slower than his (his kids can’t also think that he has aged 23 years in 3 hours). So how do you resolve this lack of symmetry with the requirement that outcomes need to be symmetrical from both these reference frames?
Granted, in this scene Matthew McConaughey ages due to gravitational time dilation. Is that somehow make things different? Would a similar scenario not be possible with time dilation solely caused by travelling at very fast speeds?
(Please let me know if I’m not making sense with these questions, and I’ll try to reword them)
Well, parts of interstellar are accurate. :) That being said, time dilation due to gravity is real. Go someplace heavy for awhile and then leave and you will travel far into the future. The spaceship-observer example is special relativity. The gravity thing is general relativity. I’m not sure I have a non math explanation here so, simply put, time dilation due to gravity is different.
You can get a similar outcome by going somewhere real fast, then turning around, and going real fast again back towards the start. In the rocket frame that may take, say 10 years, but more years will have passed by on Earth.
You may think this breaks the symmetry I brought up earlier, and it does, but that symmetry breaking occurs when the rocket accelerates a whole bunch turning around and heading back home. On the outbound journey though the rocket will think the earth clock is slow, and vice versa. Similarly, on the return journey the same thing occurs. During the acceleration phase though things gets real weird. Or weirder I should say.
Wait, you’re telling me it’s not scientifically accurate to say that love is the one thing we’re capable of perceiving that transcends the dimensions of time and space? /s
Ah, okay that answers my question then. It’s the acceleration and deceleration that changes things. Thanks for bearing with me so far and answering all my questions!
You are welcome. Thanks for the interest in physics.