bigdogchris
Fully [H]
- Joined
- Feb 19, 2008
- Messages
- 18,708
Why is this making headlines now? It has been known for decades that the closer to light speed you go, the slower time moves for you.
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Instead of explaining it from the ground up, it's easier to think of it this way: Because everything else is defined using it, including time and space. Physicists slow and speed up time itself and add more dimensions to space to fit c, not the other way.
Michio Kaku - he's quite famous, funny, I even have several of his books. He's a player on all these History and Discovery channel physics and astronomy shows.
Seems like you are the only one fixated on his disability. I know he's brilliant, and handicapped... I've heard things though about how he's kind of an ass once you get to know him. *shrugs*
He's actually really fun and nice if you talk to him though, less of a hand-puppet astronomy teacher... which I've noticed I'm also guilty of, and here I thought it was simply my Italian genes kicking inThere's also that Tyson DeGrasse something or other guy; I guess he's personable, but I've always found him cheesy and annoying on those shows.
Sounds like the backstory for a Fallout-like video game.Theoretically, such a space ship would allow the crew to repopulate the earth if they found our species had become extinct during their flight.
Instead of explaining it from the ground up, it's easier to think of it this way: Because everything else is defined using it, including time and space. Physicists slow and speed up time itself and add more dimensions to space to fit c, not the other way.
For me the whole traveling at the speed of light thing and time traveling things has always been a funky subject, namely because photons traveling from the subjects traveling at or near the speed of light would be like a slide show. Say a baseball pitcher can throw a baseball at 101mph and picture he is traveling at 101mph and throws the ball out of the back of the car, how fast is the ball traveling? To me, this is all relative, pun intended.
Say you had a really really long string. You left one end stationary, and tied the other end to the really fast spaceship.
Said spaceship accelerates for 6 years, reaches the speed of light, etc.
Now the spaceship slows down and returns back to where the beginning of the string is.
Does that mean the ends of the string would be in multiple time periods simultaneously?
Google 'DARPA time travel'.... some weird stuff :S
Google 'DARPA time travel'.... some weird stuff :S
Say you had a really really long string. You left one end stationary, and tied the other end to the really fast spaceship.
Said spaceship accelerates for 6 years, reaches the speed of light, etc.
Now the spaceship slows down and returns back to where the beginning of the string is.
Does that mean the ends of the string would be in multiple time periods simultaneously?
Of course, that won't actually work. The reason why is that communication still requires you to send information - at the speed of light, maximum - through that cable. And because of the time dilation, it will take precisely 90 years for your signal to reach the other end. Not a very useful communication link. Do the same thing with a wormhole, however, and you'll be rocking. It's too bad we don't know how to make those yet.
I don't get it, how can you travel back in time (Technically reversing time to a point, while keeping yourself from being reversed.) then shoot another you? You would just shoot yourself, like not a younger version of yourself, just you. You wouldn't leave a copy to reverse in your place.
I listened to a Discovery Channel show on black holes and how we might be able to travel through time via them. I can't name a person from that show. Would anyone be able to name Stephen Hawking is he was not disabled?
Don't get me wrong, he is one smart person. But would he be as renown if he was not disabled?
Well then technically speaking, space exploration at great distances would be rather useless since it would require the people exploring to travel at the speed of light to even make any useful distances around even just within the galaxy. Then having them travel at that speed to return home to deliver the data, too much time would have gone by for the people at home.
Simply because it's an allowed solution to an equation doesn't mean that it's reflective of reality.
No, that is not the correct interpretation. The two ends of the string will exist at the same point in space time, but will have taken different paths to get there.
you mean we don't know how to make something for which we have no evidence of its existence? Simply because it's an allowed solution to an equation doesn't mean that it's reflective of reality.
Very important words. I'm not speaking against HOCP4ME's post. But in general people and their fantasies all to often seem to forget this important principle. There is a difference between what's logically possible and what's actually possible.
you mean we don't know how to make something for which we have no evidence of its existence? Simply because it's an allowed solution to an equation doesn't mean that it's reflective of reality.
We have evidence that black holes exist, and according to the equations governing black holes, some of them should produce wormholes. Whether any of these are traversable, exist for more than a fraction of a second, or even work within the laws of general relativity, however, is unknown.
I look at the existence of wormholes the same as the existence of other intelligent civilizations: we've never actually seen them, but according to what we have seen, they should almost certainly exist (even if they will never be more than a curiosity from our perspective).
Hey man, my post wasn't directed at you. What I think gets a little too fruity is where there people imagine alternate universes where I chose not to post in HardForum, rather than to post in HardForum.
People said the same thing about black holes until we started seeing one in every galaxy...you mean we don't know how to make something for which we have no evidence of its existence? Simply because it's an allowed solution to an equation doesn't mean that it's reflective of reality.
I know it wasn't directed at me. No offense taken.
And ah yes...the many worlds theory. That's another whole can of worms. Although its main purpose is as one of the many explanations of time and time travel paradoxes. One off the (few) things physicists still don't understand hardly at all is why we experience time in such a linear, directional fashion. According to classical and relative theories, time should be just like any of the spacial dimensions, and the difference between past and future should be no greater than the difference between left and right. But it's obvious that's not the case, for unknown reasons.
Would this ship be going to meet the aliens that Hawking believes in?
I hate to seem that I'm picking on you, but I'd like to correct some things in your post (sue me, I'm anal). Many worlds is an interpretation of the quantum mechanical process of measuring an observable; it wasn't developed to deal with time travel and the paradoxes it brings. If you'd like to read on the topic, go ahead and google it, as well as the Copenhagen interpretation - as they are competing view points.
Also, it's not quite true that we don't have an explanation for the arrow of times. It's true that many physical phenomenon are invariant under time reversal, but as you've pointed out there is a definite arrow to time. The reason is pretty simple, as it turns out: entropy. It appears as if the universe prefers to maximize its entropy, and this gives time a definite direction. If we reversed the arrow of time, we would be reducing the entropy of the universe - which is mathematically forbidden.
Think about it. Say you walk across the room and in so doing you radiate heat into the environment. If we reversed this process we would have to take all that energy and put it back into your body - which can't be done as that heat has been lost (otherwise perpetual motion machines would be commonplace).
My problem with time travel into the past is that we would have to assume that the past exists at the same time as the present. Forward time travel does make much more sense.
For someone who can't talk he sure does talk alot, he is lame.
2 jokes in 1.
Time for theory is over, time to try to reach the speed of light.....which is unlikely possible.
That's pretty much right. You can go 99.9999%..etc the speed of light, but not 100%. In order to get that last fraction of a percent would require more energy than there is in the universe.
I do understand the concept of entropy and how it gives time a direction. I'm not sure why I wasn't thinking of that when I posted. The way I understand it, entropy is not only why time has direction, but how we define that direction: given state A and state B, whichever state was lower entropy existed "after" the higher entropy state, correct?
I don't quite understand how many worlds explains the quantum effects of observation...care to elaborate on that? Is it that every observer exists in his own universe, which consists of everything he has observed up to that point?