time travel

[GuidoHunter]

Re: time travel

You can't bend measurements. It would be like making a 7 inch long object 8 inches long without changing the object.

Uh, problem with semantics here.

You can't measure an eight inch long object as seven inches long.

You can, however, make an eight inch long object seven inches long simply by accelerating it, as per Lorentz Contraction.

The reason you couldn't measure it is because the measuring device would also contract, as it is moving at the same speed, and if it were moving at a different speed the object couldn't be measured due to the impossibility of simultaneity with regard to time and space dilation (the two objects would have to be colocal).

--Guido

http://andy.mikee385.com

[CypherToorima]

Re: time travel

Time dilation exists, but time travel does not. Although time dilation is very similar to time travel, while time travel happens in an instant while dilation does not. So say you orbit the earth for three years at 99% lightspeed. When you come back down, 150 years has passed for everyone else. So you'll have great grand-kids your age. Many new presidents have been elected (assuming the U.S. has stayed a democracy), and we may be at peace or at war with another country.

[GuidoHunter]

Re: time travel

Holy ****, it's Cypher.

I still wouldn't rule out time travel or (moreso) instantaneous transport, but it would be near impossible for us were it possible at all.

--Guido

http://andy.mikee385.com

[Jhairric]

Re: time travel

if someone were to travel back in time and change something how would you know. And if someone did change something they would have an immediate understanding of what they did and how it turned out wouldn't they? because up until the time they traveld throught time they would be living in the changed world and would have no idea that it was him that changed it. but really what is time it's just how long it takes the earth to rotate so how could you go back.....and what is the past? just your memories and how you precived things, so to go back in time you would in a sense have to convert everyones memories into reality which would only allow you to go back a limited amount of years. If any of this makes sense tell me becasue i always confuse myself when i think about this subject......

[CypherToorima]

Re: time travel

I read my response, and I realized what I typed was not exactly what I meant. That first sentence was more of a recap of the general consensus of the thread.
From what I have heard, the only way to go back in time was to go faster than the speed of light. Then I didn't really get the explination of why that was so. But they said that if one were to go back in time, it would create an alternate reality for that person, since the have gone back and changed the past by just being there.



and something bothered me. A black hole is not a rip. It's a super-massively dense mass. Sorry, that just kinda bothered me when I read it.

[trillobyite]

Re: time travel

and something bothered me. A black hole is not a rip. It's a super-massively dense mass. Sorry, that just kinda bothered me when I read it.

The center of the black hole is the singularity, the dense mass. Since it distorts the laws of Physics, the singularity actually rips the space-time and creates the event horizon (point of no return). A black hole is not just the singularity, however, as it includes the event horizon. Thus a black hole is a rip in space-time consisting of a core of a super-massively dense mass.

[Idonnoimconfused]

Re: time travel

Einstein's special theory of relativity basically explains that time travel is a unique possibility, but only if we can create a machine which would cause us to travel at close to the speed of light. That will not happen for at least a few millenia, so I doubt we have anything to worry about.



There are plenty of movies and games which deal with that theory. Have you ever heard of the JourneyMan Project? It's a series of computer games in which humanity discovers the secret to time travel and numerous measures are taken to contain its power to specified facilities. Of course, something goes wrong. If you're interested in that kind of stuff I recommend you check it out.

I'm sorry, but your first statement is wrong.
Theory of Relativity states if we go the speed of light - Time as we know it, will stop. Also, as we go faster (Near the speed of light) time slows down and things APPEAR to get shorter. And going faster then the speed of light would make it seems that we're heading back in time.
Example of that: Your traveling 4x the speed of light to another planet. You land there. Now since you're going faster then the speed of light, the light that would first get to you is when you first landed, so you would see yourself going backwards. Bad explanation, but deal with it.
You obviously never read about the theory of relativity.
You lose, sorry.

[GuidoHunter]

Re: time travel

I'm sorry, but your first statement is wrong.
Theory of Relativity states if we go the speed of light - Time as we know it, will stop. Also, as we go faster (Near the speed of light) time slows down and things APPEAR to get shorter. And going faster then the speed of light would make it seems that we're heading back in time.

Where, in the Theory of Relativity (either part), is time stoppage discussed at all? Or what will happen if we go the speed of light?

Also, Lorentz contraction exists. There is no "appear".

And why do you go spouting off about what happens if we go faster than the speed of light? We can't, so don't suggest you or anyone knows what would happen.

--Guido

http://andy.mikee385.com

[Idonnoimconfused]

Re: time travel

Where, in the Theory of Relativity (either part), is time stoppage discussed at all? Or what will happen if we go the speed of light?

Also, Lorentz contraction exists. There is no "appear".

And why do you go spouting off about what happens if we go faster than the speed of light? We can't, so don't suggest you or anyone knows what would happen.

--Guido

http://andy.mikee385.com

People have speculated what would happen if we went faster then the speed of light, I never said it was a theory or anything to that sort.
Also, yes it is.

Anything travelling at the speed of light is frozen in time. The general reaction to this statement is "Huh?" but with a bit of explanation it can be made clear. It all goes back to Einstein's theory of relativity: time is relative to the observer. Once again skimming over the details (which, it seems, only Einstein would understand), we discover that as an object accelerates, time slows down relative to that object. It seems that time and speed come together at - you guessed it - the speed of light. This is to say that a person riding a beam of light would be frozen in time - relative to everyone else, he could travel for several million years without aging a single second. To himself (since, relative to himself, he will always be stationary) time appears normal - it's just that the rest of the universe seems to be aging infinitely quickly!

Are you happy now?

[trillobyite]

Re: time travel

I'm sorry, but your first statement is wrong.
Theory of Relativity states if we go the speed of light - Time as we know it, will stop. Also, as we go faster (Near the speed of light) time slows down and things APPEAR to get shorter. And going faster then the speed of light would make it seems that we're heading back in time.
Example of that: Your traveling 4x the speed of light to another planet. You land there. Now since you're going faster then the speed of light, the light that would first get to you is when you first landed, so you would see yourself going backwards. Bad explanation, but deal with it.
You obviously never read about the theory of relativity.
You lose, sorry.

Where did my post every contradict your rebuttal? I didn't state that the machine would have to go at the speed of light, because I acknowledge that the theory states that one would then literally reach the end of time. I stated, accurately, that the machine would travel close to the speed of light, and thus one would have the effect of perceiving that he or she is in the future. I also acknowledge, but simply neglected to state, that going faster would make it appear as though one is going back in time.

I do not see where you even attacked any one of my points, or disagreed. Someone already pointed out that I was talking about time dilation and not time travel, but as to the rest, my points did not contradict yours. Also, drop your "you lose, you don't know anything" routine. Why be a smart-ass and insult others for no worthwhile reason? It's much easier to discuss this stuff in a friendly manner, and in this thread I do not recall making an offensive statement to you or anyone else.

[Reach]

Re: time travel

I don't see why you would be concered with time stopping at the speed of light anyway.

Nonsensical garbage. Time is never going to stop, because it'll never happen, because it can't happen. Not only can an object with real mass not go that fast, you'd be ripped apart long beforehand unless you plan on warping or something, in which those laws don't apply. It's like saying particles SHOULD stop moving at absolute zero. Great. Will it ever happen? No, it's not possible.

And I can't agree with a black hole being a rip. Near infinitely curved space time, yes, however there is no tear in the fabric XD There is no 'rip' at the event horizon, just a change in gravitational field so strong no physical thing could escape its pull. I suppose the terms 'rip' and 'infinite' are used improperly to skip complicated explainations.

[trillobyite]

Re: time travel

Nonsensical garbage. Time is never going to stop, because it'll never happen, because it can't happen. Not only can an object with real mass not go that fast, you'd be ripped apart long beforehand unless you plan on warping or something, in which those laws don't apply. It's like saying particles SHOULD stop moving at absolute zero. Great. Will it ever happen? No, it's not possible.

You got me on the whole time dilation thing before, but I'm pretty sure the theory states that any object travelling at the exact speed of light would literally reach a point in which time ceases to exist. I doubt one can get an object or a person to reach that speed which is why I'm assuming building a time machine is practically impossible.

And I can't agree with a black hole being a rip. Near infinitely curved space time, yes, however there is no tear in the fabric XD There is no 'rip' at the event horizon, just a change in gravitational field so strong no physical thing could escape its pull. I suppose the terms 'rip' and 'infinite' are used improperly to skip complicated explainations.

Well I derived my statement from this site: http://www.avinashv.net/2005/04/13/black-holes/

And it states in these words:
" black hole is unbelievably dense and massive. It has such a strong gravitational field that even light cannot escape. This is a Schwarzschild black hole.

A black hole is composed of two main parts: the singularity and the event horizon. The singularity is the core of a black hole. At the singularity, the known laws of Physics cease, and as a result the singularity actually creates a rip in the fabric of space-time. The event horizon is the point of no return, the opening of the rip in the fabric of space-time, beyond which no object can return. Once inside the event horizon, all points in space-time (read: events) stop. The radius of an event horizon is called Schwarzschild radius."....etc.

According to the site the singularity of the hole actually rips the fabric.

[Reach]

Re: time travel

You got me on the whole time dilation thing before, but I'm pretty sure the theory states that any object travelling at the exact speed of light would literally reach a point in which time ceases to exist. I doubt one can get an object or a person to reach that speed which is why I'm assuming building a time machine is practically impossible.

Um, the theory states time dilates exponentially to a change in energy/gravitational field intensity. "Theoretically" time "should" stop at the speed of light, but the theory does not claim this, because it is simply not possible. Instead it states that to travel at such a speed would require an infinite amount of energy, thus impossible. Time cannot cease to exist because one could never, ever reach the speed of light (without warping).

And according to that site is wrong. There is no rip in space time. Some people 'speculate' black holes rip into some alternate universe, but there is absolutely no proof of this. A singularity just curves space beyond measure, to a point that is so small and dense it is defined as infinitely both, making it absolutely impossible to know what is happening there because of the quantum(random) effects happening at such a field intensity (which essentially means our mathematical solutions give us undefined answers). Einstein actually discovered it before hawkings found proof, but discarded it because he believed the undefined solution to be impossible.

Then again it's hard to say. There's quantum loop theory, and infinities there arn't a mathimatical problem. Generally, as of right now we don't know, if it extends infinitely, if it's small beyond measure or something else, but a lot of theory should be testable soon, so we will learn a lot. A big part of the problem right now is the math, and the use of constants in a lot of situations are used to fill in unknowns, which is likely why undefined solutions occur.

[flamingspinach]

Re: time travel

rofl

I like how nobody seems to have read my post at all :/

[Reach]

Re: time travel

I read it.

Just because noone replied to it doesn't mean it wasn't read, though, because of it's length and the constant QUASI SPATIAL, it probably was not read by many XD

Not to mention you essentially said what others have said, except in another manner, with more detail.