theANTIcraig

if i were to travel to a star...say 5 light years away (10 LR round trip) at 99.99999999 percent the speed of light and then come back to earth...which of the following would occur: 1) 10 years would pass for me (the traveler) where thousands of years would pass for those back on earth or, 2) a few hours would pass for me due to time and space dilation, and 10 years would pass for those back on earth thanks

Well, it can be said that, disregarding all frames of reference, that for the two objects relative to each other, one of them will experience time dilation (the one traveling faster) and the other will not. What if you treat the traveler as one entity, and the rest of the universe as the other entity. For whom will the time be slowed down for? Is the traveler traveling at near speed of light relative to the universe, thus slowing his own time down compared to the rest of the universe? Or is the rest of the universe traveling at the near speed of light, thus leaving the traveler the only one experiencing the "actual" sense of time?

for a while now theres been something regarding relativity that i just cant seem to understand...i asked my physics professor and it looked like he had a reasonable explanation but he doesnt speak english very well and it was hard for me to understand his explanasion.... as we all know relativity states that there is no ABSOLUTE velocity or speed...but it is only measured relative to its surroundings or environment... so when talking about time dilation...for example...a rocketship versus the earth...the rocketship is moving near the speed of light...and the earth is still...so time is passing slower on the rocketship than on earth...therefore when the rocketship returns...the brother on the rocketship will be younger than his twin on earth b/c lesss time has passed for him... what i dont understand is how relativity distinguishes WHICH object was the one traveling near the speed of light...b/c the way i see it...its paradoxical to think that the spaceship should be the one experiencing the time dilation....b/c who is to say that the rest of the universe isnt moving away from the spaceship...thus causing the REST of the universe to experience the time dilation... im pretty sure my professor was telling me something about acceleration...and i still cant see why that would be relevant...b/c the way i see it...theres 2 different entities being compared...the universe and the spaceship.... how do u find out which is experiencing the slowed down time?? which entity is traveling at the speed of light and which is considered stationary?