Time Dialation AKARAS Nietzschean Okay, I am the slow one here on the SS when it comes to some things. This may have been discussed before, and if so, I am sorry for bringing it up again. Anyway, I was wondering if someone could explain to me what TIME DIALATION is, and how it works. And if I misspelled it. Can it be avoided, etc. I can handle the dtails. I love details if anyone is up to it Thanks. Telest Human Okay, I'm not exactly sure what you mean there, but you could say that time dialates when the speed of light approaches. Similar effects (at least in Andromeda universe) happen near singularities (extremely strong gravity wells such as black holes). Well, how it works: that gets even trickier (at least with my limited knowledge). I think it all pours down to the speed of light: the speed of light is always observed to be c in vacuum (albeit there seems to be some theories that this might not be exactly true). This is true even if we are moving and irrelevant of the direction of our movement, the speed of light relative to US is always c. What this observation leads to in practise is that if we were moving at half the speed of light, we would still observe all light at moving at the speed of light:). However, to keep things consistent we "length" of things must change when we accelerate. For example, an object moving at a very high velocity relative to our solar system could observe the distance between the Earth and Sun to be only a few kilometers apart. Hence, from his point of view, it's only a short trip and can be taken in a very short time. However, looking at the event from Earth, we would see the distance as "normal". Hence, since the speed of the ship cannot exceed the speed of light, it would take several minutes for a ship to travel the distance. Our subjective time is different from his. From his perspective, everything happens in the blink of eye, from ours it takes several minutes. Time dialation has occurred. Was this anything like what you were after? Christopher Nietzschean Telest got it basically right -- except the word is not "dialation," it is dilation. As in when your pupils dilate -- it's the same word, meaning to expand. Time dilation arises from the Special Theory of Relativity. Basically: every observer throughout the universe experiences the same laws of physics. No frame of reference is more "right" than any other (hence Relativity -- all observations are relative to the observer). Now, the speed of light is a factor in a lot of fundamental physics equations -- change it, and you change the laws. But all observers, no matter how fast they're moving, have to experience the same physics, and that means they have to measure the same speed of light. So the way they measure distance and time has to change to compensate for their own motion, so that they always measure the same speed of light. Time and space are not the constants we assume they are -- only the speed of light and other fundamental cosmic properties are constant. The only reason we think of time and distance as constant is because in normal life we never move fast enough for the differences in our measurements of time and space to be noticeable. Now, since every frame is equally valid, there's a weird effect. If I'm moving away from you at 95 percent of the speed of light, you see me slowed down by a factor of about three times -- an hour for you is 20 minutes for me. So you'd think that I'd see you going three times faster. But I don't -- because in my equally valid reference frame, I'm standing still and you're moving at 95% of lightspeed. So I see you slowed down three times. Sounds like a paradox, but it actually makes sense -- because we see each other by the light travelling between us, and if we're moving apart (or toward each other) at close to the speed of light, then the travel times for those beams of light are constantly changing, and that alters the length of time you perceive my actions to take. And vice-versa. Does this mean time dilation is just an optical illusion, a trick caused by changing travel times of light beams? No, because the way two objects react to each other depends on the exchange of signals and forces between them, and those travel at the speed of light -- so the speeds and distances we perceive are the ones that determine how we're physically affected. So for all practical purposes, this is reality. Can time dilation be avoided? Not really, because it isn't an aberration, it's a normal part of how the universe operates. And time dilation is a relative concept. We may perceive ourselves as being non-dilated here on Earth, but we're certainly dilated relative to a distant galaxy receding from us at a high fraction of lightspeed. Everybody, always, everywhere, is time-dilated relative to something. Heck, if I rode past you on my bicycle we'd be time-dilated relative to each other, although by an infinitesimal amount. But is it possible to travel very fast between stars without being greatly time-dilated relative to your planet of origin? Theoretically, yes, if you travel by warping spacetime. In effect, you're not actually moving at all when you do that, just changing the amount of spacetime between you and your destination. So since you haven't accelerated relative to your homeworld, you aren't time-dilated relative to it. But according to current theory, this would take an impossible amount of energy, and in certain circumstances could create time paradoxes, and thus probably isn't allowed by the laws of the universe. AKARAS Nietzschean Thank you Telest and Christopher for the explanation. I think understand it now. Telest Human Quote: Posted by AKARAS: Thank you Telest and Christopher for the explanation. I think understand it now. I think we should now sell this thread to some physics book and make a lot of $$$. j/k. AKARAS Nietzschean ^Hey, why not. I've got lots of questions, and you have lots of answers. Sounds like a textbook to me.