Relativity question
Hello <insert recipient here>,
I recently learned about “The Twin Paradox”, in which one twin of a pair was loaded onto a spaceship, rocketed into distant space at near light speed, and then returned to earth at an equally fast speed. From what I read, according to the point of view of the twin on earth, the space-traveling twin will have aged slower (let’s say that ten years passed, but the space-traveling twin will have only aged one year.) Now apparently, things like this have been proven by experiments using clocks and muons and whatnot, so I’m willing to take it on faith. Things get more difficult for me to grasp when we change the point of view.
From the point of view of the astronautic twin, does his trip take ten years while the age of the earth (and everything moving at near-earth speeds) appears to have only aged by one year? (a flip-flop of what happened when the point of view was different)
If so, from the points of view of everyone in the universe, does the astronautic twin show up both ten earth-years later and only one year older AND one earth-year later but ten years older? OR is there some sort of splitting of realities, where in one he’ll show up on earth ten years later, and in another reality he’ll show up on earth only one year later?
John R. Filleau
Specifically I'm looking for any sort of data/previous experiments/calculations that could help me wrap my mind around this concept. Dissemination throughout educational channels would also be appreciated.
I recently learned about “The Twin Paradox”, in which one twin of a pair was loaded onto a spaceship, rocketed into distant space at near light speed, and then returned to earth at an equally fast speed. From what I read, according to the point of view of the twin on earth, the space-traveling twin will have aged slower (let’s say that ten years passed, but the space-traveling twin will have only aged one year.) Now apparently, things like this have been proven by experiments using clocks and muons and whatnot, so I’m willing to take it on faith. Things get more difficult for me to grasp when we change the point of view.
From the point of view of the astronautic twin, does his trip take ten years while the age of the earth (and everything moving at near-earth speeds) appears to have only aged by one year? (a flip-flop of what happened when the point of view was different)
If so, from the points of view of everyone in the universe, does the astronautic twin show up both ten earth-years later and only one year older AND one earth-year later but ten years older? OR is there some sort of splitting of realities, where in one he’ll show up on earth ten years later, and in another reality he’ll show up on earth only one year later?
John R. Filleau
Specifically I'm looking for any sort of data/previous experiments/calculations that could help me wrap my mind around this concept. Dissemination throughout educational channels would also be appreciated.
Comments
The astronaut twin shows up ten years later, but it was only a year to them, that's how it works.
Whoa, that should totally be on our SCIENCE! movie list.
The pure perspective of the twin on Earth is that ten years passed.
There are no other perspectives.
this is an issue that I always had witht theory of relativity too, but let me try to say it so the dilemma is a little more clear. Let's make it a more logical example, if you're standing on the side of the road, I drive past going 50 mph from your eyes. From my eyes however, my body is still, and you just went past my car at 50 mph. Relative to the earth, the space ship was moving at the speed of light. However, the oposite is also true. If we look at the space ship as standing still, the earth is travelling at the speed of light.
But like hammy said, you gotta go with the pure perspectives.
Now here's another quirk to it for ya:
as a low speed example, here:
65 mph <----(car A) (*"rest" object*) (car
car A would see car B as moving at 85 mph away, right? nice and simple. now let's get theoretical.
if two ships are travelling in opposite directions, one (ship A) at .75*c, and the other (ship
.75*c <----(ship A) (*"rest" object*) (ship
.75*c + .5*c = c(.75+.5), so it's 1.25*c
basic motion would lead one to beleive that ship A would see ship B as moving at 1.25*c... but c is the speed limit of the universe, right? well, that whacky Einstein had to go and mess up my head even more by saying, yes, c is the highest relative velocity possible, so, he came up with a more complex formula for calculating relative velocity.
relative velocity = (Vb - Va) / (1 - Vb*Va/c^2)
this would put ship B in the above example (relative to A) as moving at .9090909(bar)*c . Hence, there must be time dilation to explain the difference in relative velocity. I hate Einstein. I hate him so much.
It also made a big deal of the time travel, because Ender had apparently been alive for thousands of years by space traveling... but I can't exaplin it as well. Read the book. Or watch that movie, I haven't watched it but I'll certainly take Mario's word for it.
EDIT!! This was my 69th post and I didn't do anything.... oh wells. lulz!
*sad face* :[
"You still owe me four years back rent on that ship."
"Four years for you, but it's been only three weeks for us. We're on the high end of the lightspeed curve, remember?"
"Relativity is a damn lousy excuse for not paying your bills!"
heh, no idea. all i know is that he was insane.
oh, and Vb and Va are velocity of ship A and velocity of ship B.