just a tho

[Xminent]

just a tho if we ever invented time traveling wouldnt u think we would see the people in the furture who did come back to this time to study about us.

Or maybe thats what the UFOs is?

Or maybe earth and human life dies out before we could?

Maybe is impossable to go back in time?

But if we did wouldnt we go back in time and stop all the bad things that happened on earth like WW2?

[RQ]

That poses several logical as well as perceptual problems aside from the physical impossibilities:

Think about it, if WW2 is stopped, then who is going to remember stopping it in the future? It never happened so why bother going back and stopping something that never happened, yet if you don't it would happen.

Also where did this stopping come from? If you went back and stopped it, but it made you come back, then the whole process of stopping came out of nowhere. Think of it like the scientist and the magazine:

A scientist goes in the future and sees a magazine with an important theorem. He goes back in time and teaches it to a student, who publishes it a year later. Where did the theorem come from? Nowhere. It doesn't make sense.

P.S. What makes you think WW2 was such a bad thing?

[pat]

One of the premises (well, the word "premises" may be elevating the writers a bit) of the movie Repo Man is that UFOs are really time machines. (Paraphrased):

Miller: If you think about it, there had to be a time when there were no people. So, where did they come from?
Otto: How the f*** should I know?
Miller: From the future. And, how did they get there? In space-ships, which are really.... yes, you've got it.... time machines.
Otto: Miller, did you do a lot of acid back in the hippie days?

[BearDin]

If there were no people at a given time, how could there be people then in a later time in the future to travel back to the now? What the hell is time? Anyone ever wonder if time was maybe reverse, like what we see as future is really the beginning, and the past is the end, some weird kind of reversal?

[Malaktix]

If just one person was to exist in a time that they didnt once exist in, wouldnt it cause a complete imbalance of matter? (I don't even know what I mean by that, I did when I typed it, then couldnt really explain it)

But anyway, ever heard of the butterfly effect?

Just one person existing in a time that they originally didnt would completely change the course of events.

Even just the extra oxygen consumed by that person would have drastic effects in the long term.

Can't quite remember the quote. I think it's something like "If a butterfly flaps it's wings somewhere, it can cause a tornado somewhere very far away"

So if a person was to travel very far back in time just for a brief moment, then return the future, I believe they would return to a completely different world.

The more I think about it, the more I think that traveling back in time would not be possible.

[RQ]

If there were no people at a given time, how could there be people then in a later time in the future to travel back to the now? What the hell is time? Anyone ever wonder if time was maybe reverse, like what we see as future is really the beginning, and the past is the end, some weird kind of reversal?

The people came from the people that came. That's the part that makes sense.

The psychological arrow of time is with accordance to the thermodynamic arrow of time. Thus we can tell the two events of the past leading to the future with the increasing of entropy. If it was the other way around then what we would call the past would be the future and vice versa though it wouldn't be possible.

[3l3ctr0]

but just for discution say we wore able to go back in time. would u actualy go back in the same "time line" or would u go in to another "time line" totaly independent of the one u came from. then if u went back into the "origanl time" u came from the other alternet time would disaper. or would u have created anoter "time" all together which fits into the part of the movie that we arived from the future and there was nothing befor us... :?

pat

Miller: If you think about it, there had to be a time when there were no people. So, where did they come from?
Otto: How the f*** should I know?
Miller: From the future. And, how did they get there? In space-ships, which are really.... yes, you've got it.... time machines.
Otto: Miller, did you do a lot of acid back in the hippie days?

[3l3ctr0]

hey i just thought of sumthing else... what if we were in a comma or we are sleepin and when we die... we are then in "reality" and we will have a chance to right our mistakes... so in a way we are actualy travalin back in time. or another thing that could be hapining is that we are not born yet but we would be when we die and once again we can right our wrongs, so that we have a second and better life... :?

[brasileiro]

hey i just thought of sumthing else... what if we were in a comma or we are sleepin and when we die... we are then in "reality" and we will have a chance to right our mistakes... so in a way we are actualy travalin back in time. or another thing that could be hapining is that we are not born yet but we would be when we die and once again we can right our wrongs, so that we have a second and better life... :?

A very interesting thought... Now, there was an old phylosopher, chinese I think, who said (I apologize if I accidentally paraphrase this), "Sometimes I believe that my dreams are the real world, while my real world is the dream. Is anything possible?" or somethin like that. But that's the gist of it... can you see where I'm comin from? Sometimes, I too feel like the dream is the real world and my life as I live it is one big dream... and it only strengthens my feeling when I can't remember what happened yesterday and can remember every detail to my dream that night. so maybe.... maybe........

[brasileiro]

just a tho if we ever invented time traveling wouldnt u think we would see the people in the furture who did come back to this time to study about us.

Or maybe thats what the UFOs is?

Or maybe earth and human life dies out before we could?

Maybe is impossable to go back in time?

But if we did wouldnt we go back in time and stop all the bad things that happened on earth like WW2?

This is something I love to spend time and ponder. Time travel, it may be possible, but it would only propel you into the past. Therefore, explaining the dopplegangers (exact duplicates of onesself). The only thing about it is, there is no real way to travel into the future. The only way we would be able to accomplish this would be to travel at the speed of light, or very close to. If we can accomplish this, we can then work on the way to make only our molecular structure speed up to that speed, and then we would just pass time by and watch it fly as we are standing/sitting still and moving at our "normal pace". Watch the movie "Time Machine" I think it's called. It will show what would happen, theoretically, if we could time travel. I will now explain, as best I can, why we can't "really" travel into the future.

Since we can create our own future, we cannot travel into something that hasn't been created yet. We would then be in nothing, and therefore, become nothing.

That simple enough? For this, I would suggest "Back to the Future". Although I don't see how they would be able to travel into the future if there was no future to travel to... anyway, travelling to the past, will change the future, as you know it. Anything you do, will change it as you know it... once again, only theoretically. The thing there is, if you DO happen to travel back into time, you wouldn't change anything because it would have already happened. Now, I tell everyone to refer to "Harry Potter and the Prizoner of Azkaban". Now I'm not a big HP fan, but when I saw the time travel part, it got me.

NOW... we go to dimensions. Everything that has ever happened, is caught in a still-frame in time. every little millionth of a second is stuck in time... and it is through this that we would be able to time travel. Now everything is caught in time, but it is also happening in another dimension... exactly how it happened before, and there are infinite dimensions, therefore, creating infinite repeats of what has happened before, not to mention, infinite possibilities of what COULD have happened. That leads us to believe that there are also infinite possibilities of what WILL happen... of which, we will only do one... BUT all the other dimensions will choose their own. It goes on from here... and just gets either a little easier or a little harder to understand... depending on who you are.

[brasileiro]

And from here, we will go into stopping incidents. Like I said previously, if we were to travel back into time, we will only repeat what has happened before. BUT, in another dimension, we will stop what has happened... that will happen in several dimensions. But, for now, we will assume that what has happened to this world has been for the best. That is all we can do. Since we will never know how it WOULD have turned out (we can only speculate and assume what could have happened), we will just leave it at that. This brings us into the Worm Hole theory. Worm Holes aren't fully explained yet, because we do not yet have the technology to explore them. One theory I like to stick with is that the Worm Hole is an entrance to a dimension unbeknownst to Human kind, and is like I explained before, just another dimension in which our world is duplicated and manipulated to either what we wanted to happen, or what could have happened if we did something different. And since there are infinite possibilities, then there is mathematically no possible way to get back to our own dimension... as we know it. We may find a dimension exactly like ours, but it would not be ours... and we would not be able to prove otherwise. Its all just very confusing sometimes...

[Twix18]

how many different paradoxes are there with time? lets sugest that paradox A is the situation of going back in time to kill you grandfather so that you are not born... but if you ar not born than how can you go back and kill your grandfater... ect.

how many are there that we havent even thought of?

[jinydu]

According to the laws of Relativity, we certainly can "travel into the future" (although you do have to be careful with the phrase, remember that there is no absolute time). Probably the two simplest ways to do this are:

Travel at speeds close to the speed of light (relative to observers on Earth). According to Special Relativity, your clocks will run slowly relative to those on Earth. In fact, this effect occurs at any nonzero speed, but it generally becomes noticeable only at high speeds. Still, it is true that astronauts on board the ISS aged roughly 1 second less than their counterparts on Earth.

Stay inside a strong gravitational field. According to General Relativity, observers outside the gravitational field will observe clocks inside the field as running slower than normal. Thus, if you could hover just outside a black hole, your clocks would run slower than those in the outside universe, i.e. you would "travel into the future".

[Twix18]

wow... although that was slightly interesting it wasnt what i was going for... try this. use your imagination... your wits... heck even common sense and logically figure out the problem for yourself... you seriously look like your just copy and pasteing from one thread to another, changeing just the theory youve found to support a question that was not asked.

[brasileiro]

I thought I said that though... we can travel into the future, but it won't be what we think of it as. I said we would have to reach a speed fast enough or close enough to light speed to slow down our time in relativity to the time around us. I also said to watch the movie "Time Machine" to find out what i was talking about. I may not know too much about relativity, but this is something I can relate to. It's something I've discussed since Back to the Future came out...

[jinydu]

Problem is, as you hopefully know already, Hollywood often gets its physics wrong.

In any case, if I were to just post my own random thoughts, without any careful logical reasoning or experimental evidence behind it, I would almost certainly be wrong. True, imagination is important, but you have to be familiar with the subject that you're thinking about to have any real chance of being right.

[Twix18]

not really. you seem to be under the illision that every scientist who created your perscious laws was always afraid that if they didnt use others reaserch and be constantly in fear of being wrong that they were failures. einstien was a failure all his life, he took chances made mistake was laughed at and fired... but it was his imagination, his lack of fear about being wrong that gave him the corage to come up with a NEW idea... you are mearly spewing out the texts of others without adding anything of your own

[jinydu]

Einstein was no amateur, nor did he develop his theories in total isolation of previous work. Throughout "On the Electrodynamics of Moving Bodies", the paper where Einstein first introduced the key ideas of Special Relativity, we see references to prevoius works on electromagnetism. In addition, the Principle of Relativity (that the laws of physics apply equally in all inertial reference frames) did not appear out of nowhere. Instead, it was based on previous work that established the symmetry between moving magnets and moving electric currents.

The common myth that he failed math in school is wrong; in fact, he was a very successful student in physics and math (though he did have a reputation among his teachers of not being serious enough). Although he did fail a foreign language entrance exam, he studied at the prestigious ETH, one of the leading universities in Europe in his day outside of Germany.

Furthermore, he was not the first to come up with the Principle of Constancy (that the speed of light in a vacuum is the same for all inertial observers), one of the biggest cornerstones of the Theory of Relativity. In fact, this had been predicted decades earlier by Maxwell's Theory. What Einstein did do, and this enabled him to successfully develop Special Relativity, was provide the correct interpretation of this important principle.

Not only that, Einstein certainly wasn't a disrespected failure all his life. During the 1920s, he was a towering figure in physics. In fact, deBroglie's famous Ph.D. thesis, which is crucial to quantum mechanics, was approved because of Einstein's recommendation.

Was Einstein a brilliant genius who came up with some very good ideas? Yes. Was he ignorant of previous work? No.

[wendy]

The fact that one can freely refer to other books and papers does not in any way diminish that one can work in isolation. The isolation is not that there's nothing to read, but no one you can talk to.

Maxwell's paper on Electromagnetism showed the existance of electromagnetic waves, that these travel at the EM velocity, and the nearness of light to this, suggests that light travels in the same medium.

The rules of Electromagnetism are not Newtonian-relative. That is, the speed of an EM wave happens in just one Newtonian frame: the etherfer. The Moresley-Michaelson experiment failed to find the etherfer, and many people speculated on what was happening: ether was being dragged by large objects, things contracted in the direction of travel, or time expanded.

Einstein's look at relativity was designed to find out what theoretical basis could explain the Moresley-Michaelson experiment, and a number of his own thought-experiments. Specifically, that we do not see standing EM waves suggest that space-time must be linked at that rate, and that the concept of a standing EM wave is somehow concurrent with the instant.

It is certianly true that Einstein referenced older papers. But the heavy work of framing things in terms of a single theory is his in isolation.

[jinydu]

Also, don't forget that Einstein's theory was not just vague speculation. The Theory of Relativity started with a few simple, but precise postulates, and built upon them systematically, and gave specific, quantitative predictions.

Einstein didn't simply throw up ideas like "all motion is relative". Instead, he made precise predictions that could eventually be settled by experiment, such as:

If an inertial observer observes a clock moving with speed v relative to the observer, then the clock will appear to run more slowly than the observer's clock by a factor of 1/sqrt(1 - (v^2)/(c^2)), where c is the speed of light in a vacuum.

Not only that, Einstein was able to give a mathematical proof of why this had to be the case.

[wendy]

Einstein's claims are that there exist transformations of space such that the laws of electromagnetism happen in any frame of reference, when measured in that frame.

The consequences of the theory is that when there is proper motion between two frames of reference, then one can detect from the changes in the results of electromagnetism the speed of the second frame (eg slowing clocks).

The predictions are precise. How accurately they reflect nature was to be tested later in experiment. The experimental error is larger than any observed differences between the prediction and the fact, something which can not be said for newtonian relativity at the same speed scales.

W