Could always look at it from the point of view that there is x amount of energy, always has been, always will be. Introducing yourself into the timeline, again, by traveling into the 'past' will upset that. There is now more energy in the universe then there should be (You are matter, which makes you energy.. a damn lot of it too). You yourself have enough energy there to wipe out a good few major cities, if not more, with that much added energy to the universe a lot will change. A lot. Chaos Theory will make your brain explode <!--emo&:p--><img src='http://www.unknownworlds.com/forums/html//emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif' /><!--endemo-->
And trying to prove 'past'-time travel online is <span style='color:white'>pointless</span>, discussing it just as <span style='color:white'>pointless</span> <!--emo&:)--><img src='http://www.unknownworlds.com/forums/html//emoticons/smile.gif' border='0' style='vertical-align:middle' alt='smile.gif' /><!--endemo--> Paradox's are easy little things. Which makes time travel oh-so fun. There is no correct answer, fella's. Try to concentrate on the more important things, like pipe dreams (Room Temp. Superconductors? DNA Computers? Quantum Computers? Hell, Quantum physics as a whole? ;p )
Oh, a nice couple of paradox's, the first I thought of myself, probably been said before tho.
Well time doesnt actually exist, the only reason we can measure time is because we can see how something changes in realation to somethign else. Time travel assumes that time is liniar and exists as its own entity, not true according to current theories, a great book for anyone interested in this topic is <a href='http://www.amazon.com/exec/obidos/tg/detail/-/0465078354/qid=1081618683/sr=1-2/ref=sr_1_2/104-2642637-0866326?v=glance&s=books' target='_blank'>Three Roads to Quantum Gravity</a> By Lee Smolin, its presented in a very easy to follow language and you dont need to know much physics or math to understand the concepts.
If you look at some of the current theories in quantum mechanics, they present the information of the retarded wave, an energy signal that actually is from the future, but gets absorbed because of its weakness. I agree though that time isn't a physical thing, but I also think that the present is a state of being rather than just something thats there and thats the whole story.
0- Your grandfather is born 1- Your father is born 2- You are born 3- You travel back into time 4- You attempt to kill your grandfather S- You succeed F- You fail NE- You no longer exist E- You exist +1 - You Travel back to one minute past when you left. -1 - You Travel back to one minute before you left. S - You stop yourself FS - You fail to stop yourself ? - Unknown event N/A - Simpsons Episode #8235-A never aired.<!--c2--></td></tr></table><div class='postcolor'><!--ec2--> <!--emo&:p--><img src='http://www.unknownworlds.com/forums/html//emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif' /><!--endemo-->
In this, your time machine has screwed up, sending you to a time where your father has been born. You will still exist, as your father still lives. Again, it will loop until you give up or succeed.
This one deals with a looping cycle of events in which you either fail or succeed. Obviously, if you succeed the cycle is broken and if you fail it continues forever.
[Oops. Pressed send WAY too early. Oh well. And this is all guessing that you enter a new dimention for #1+2, otherwise you'd meet yourself each time you went back into time. For #3 you'd almost certainly meet yourself.
Man, do I EVER hate the mechanics of "Time"!]
[Edit 2: Actually i think it's impossible to look at this on a 2D plane (IE a sheet of paper) in it's most complex form; simply because you'd run out of paper trying to cover all the events and variables. I mean, i have 14 variables, and 3 examples, and look at how much space it's already taken! <!--emo&:0--><img src='http://www.unknownworlds.com/forums/html//emoticons/wow.gif' border='0' style='vertical-align:middle' alt='wow.gif' /><!--endemo--> ]
And even if it was possible, nothing will change the past.
The shotgun will jammed. A homeless man will get in the way between grandpa and the gun. You will be run down by a really big St.Bernard. Grandpa tripped a stone and you missed the shot.
Point is, you will never ever hit grandpa in the first place, no matter how hard you try.
Saying that you think if you can go back, but cannot create a paradox, this seems more of an issue of if you believe in fate or destiny not time travel. It seems that your subscribing to the theory that, if a man is going to die in a plane crash on July 1st and for some reason he doesn't get on the plane he'll die in a taxi. I agree with the person before that said if you can go back in time you can change it if you can't create paradoxes then you just can't go back in time. Becuase to prevent any paradoxes at all we would literally have to read somewhere that we went into the past and then go do otherwise the act of time traveling to the past would be a paradox in itself.
<!--QuoteBegin-Matthew L. Barre+Apr 10 2004, 05:07 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Matthew L. Barre @ Apr 10 2004, 05:07 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> Saying that you think if you can go back, but cannot create a paradox, this seems more of an issue of if you believe in fate or destiny not time travel. It seems that your subscribing to the theory that, if a man is going to die in a plane crash on July 1st and for some reason he doesn't get on the plane he'll die in a taxi. I agree with the person before that said if you can go back in time you can change it if you can't create paradoxes then you just can't go back in time. Becuase to prevent any paradoxes at all we would literally have to read somewhere that we went into the past and then go do otherwise the act of time traveling to the past would be a paradox in itself. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> No, no. That's not what I'm saying at all.
I'm saying that you just can't prevent that man to go on that plane and die in the crash.
<!--QuoteBegin-Skidzor+Apr 9 2004, 10:28 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Skidzor @ Apr 9 2004, 10:28 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> If you somehow reach a velocity greater than the speed of light, you enter negative time and thus have time travel. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> But wouldn't going FASTER than time cause you to end up in the future in stead of the past?
A respected scientist Dr Frank Tipler published plans for a working time machine in 1974: The machine is too big to be built anywhere on earth, it consists of a huge cylinder of very dense material. When set spinning the Tiper cyclinder creates areas which act as gateways to the past and future. The best shape for a timeship which could use the gateways created by a Tipler Cylinder is disc-like. In other words, similar to a flying saucer.
<!--QuoteBegin-JezPuh+Apr 11 2004, 12:41 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (JezPuh @ Apr 11 2004, 12:41 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> <!--QuoteBegin-Skidzor+Apr 9 2004, 10:28 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Skidzor @ Apr 9 2004, 10:28 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> If you somehow reach a velocity greater than the speed of light, you enter negative time and thus have time travel. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> But wouldn't going FASTER than time cause you to end up in the future in stead of the past? <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> No.
If you go somewhere at a certian speed, it takes 2 hours. If you go twice as fast, it only takes an hour. If you go there fast enough, you arrive at the moment you leave, the journey takes no time at all. If you go faster, you arrive before you left. If you go far enough for long enough, you can travel to any point in the past that you want. The only trouble is, you cannot get back.
<!--QuoteBegin-Umbraed Monkey+Apr 9 2004, 10:01 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Umbraed Monkey @ Apr 9 2004, 10:01 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> "Why arent we seeing visitors from the Future?"
Think about it. If man is to be able to time travel in the future, then in our history, there would be recordings of visitors. This right here tells us either a) Time travel is simply impossible for physical beings, or b) Time travel would NOT affect the past, thus paradoxes are not a problem. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> There is a simple answer to this question.
It is because the limits of time travel are this:
You cannot go back farther then when the time travel machine was built.
Remember, a time traveling machine would only go back to it's history. Of course, once it is built, you could fling yourself far into the future and see what's up.
<!--QuoteBegin-Z.X. Bogglesteinsky+Apr 11 2004, 09:56 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Z.X. Bogglesteinsky @ Apr 11 2004, 09:56 AM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> <!--QuoteBegin-JezPuh+Apr 11 2004, 12:41 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (JezPuh @ Apr 11 2004, 12:41 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> <!--QuoteBegin-Skidzor+Apr 9 2004, 10:28 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Skidzor @ Apr 9 2004, 10:28 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> If you somehow reach a velocity greater than the speed of light, you enter negative time and thus have time travel. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> But wouldn't going FASTER than time cause you to end up in the future in stead of the past? <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> No.
If you go somewhere at a certian speed, it takes 2 hours. If you go twice as fast, it only takes an hour. If you go there fast enough, you arrive at the moment you leave, the journey takes no time at all. If you go faster, you arrive before you left. If you go far enough for long enough, you can travel to any point in the past that you want. The only trouble is, you cannot get back. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> Actually, if you go twice as fast, you get there in less than half the time. It's not exactly proportional. The effects aren't really noticable until you go "fast enough," about the speed of light.
So, sending a single photon back in time by about a femptosecond by barely exceeding the speed of light is possible, but it would never happen to a person. You simply won't be able to accelerate them to that speed because of the rediculous amount of energy it would take (+ the engine, ship, and infinitely large amount of fuel they'd have to take). Also, to avoid killing the passenger you'd have to accelerate slowly over the course of about 10 years. And then there's friction...
And, if you wanted to travel back in time at any significant rate (ie, die of old age by the time you got there), you'd have to go several times that speed, if it's even possible.
<!--QuoteBegin-Dr.Suredeath+Apr 11 2004, 01:00 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Dr.Suredeath @ Apr 11 2004, 01:00 AM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> No, no. That's not what I'm saying at all.
I'm saying that you just can't prevent that man to go on that plane and die in the crash.
Taxi is not an option. Plane is the only option. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> Ok then the real question how do you know thats its not your fate to go back in time and kill him. Everything being locked into fate and nothing can change doesnt seem to be a very plausible option.
Maybe you all should keep in mind that 'time' is indeed nothing but the mental construct we use to cope with the flow of causality - which does, as has been recently <a href='http://www.quantumphil.org/' target='_blank'>proved</a> - care diddly squat for chronology. What I'm trying to say here is that just because we can't imagine a solution to the problem - our brains base any kind of assumption about a causal process on its chronology - it doesn't have to be there at all. Who says the universe cares about who your grandfather is? You are there, he is there, energy sums play no role as the universe is for all we know not self-contained, so what's the big deal? Again, I don't claim that I can solve the paradox, I merely claim that it wouldn't necessarily be a deterrent from time travel, a process regularily undertaken by verious subatomic particles, all without of them becoming fathermurderers, as I might add.
<!--QuoteBegin-Z.X. Bogglesteinsky+Apr 10 2004, 10:42 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Z.X. Bogglesteinsky @ Apr 10 2004, 10:42 AM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> Thats my point. You dont have photographs because photography wasnt invented. There is no way of getting a photograph of a time period before photography was invented. I cannot get a photo of my great great great gandmother because she died before photography existed. In the same way you could not travel back beyond the point time travel started to exist. With the wormhole idea, you would only be able to go back to the point when the wormhole begins, no further <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> That doesn't stand up to common sense or logic. You're talking about traversing time and the actual invention of a time machine ( this is absence of any use ) has no affect on time itself.
The difference between a time machine and photography is that photography is an invention in and of itself and of course cannot exist before it was invented. A time machine, if possible to build, would use something that existed prior to its creation. So there is no reason to even assume that time travel could not go back past the actual invention.
I agree with the above, but I also have to say the same about photography. A camera won't care what point of time your in it is meant to take pictures of anything, its not going to start screaming at you, "I can't do that I dont exist yet."
If it's to happen, there's much more than a person to be teleported. His clothes, the air around him, the moisture, the floor he's standing on. What will happen to the surround once he get to the past? Will there be a big boom caused by these sudden appearance of this stuffs out of no where? What happen to the air, the atmosphere that's already there?
The world and the galaxy is moving at an unimaginable speed. If we're to be teleported, doesn't that mean we're going to popped up 123,233,321 miles away in space?
Unless you can answer this question, do not attempt time travel.
moultanoCreator of ns_shiva.Join Date: 2002-12-14Member: 10806Members, NS1 Playtester, Contributor, Constellation, NS2 Playtester, Squad Five Blue, Reinforced - Shadow, WC 2013 - Gold, NS2 Community Developer, Pistachionauts
edited April 2004
<!--QuoteBegin-Nemesis Zero+Apr 11 2004, 04:18 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Nemesis Zero @ Apr 11 2004, 04:18 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> Maybe you all should keep in mind that 'time' is indeed nothing but the mental construct we use to cope with the flow of causality - which does, as has been recently <a href='http://www.quantumphil.org/' target='_blank'>proved</a> - care diddly squat for chronology. What I'm trying to say here is that just because we can't imagine a solution to the problem - our brains base any kind of assumption about a causal process on its chronology - it doesn't have to be there at all. Who says the universe cares about who your grandfather is? You are there, he is there, energy sums play no role as the universe is for all we know not self-contained, so what's the big deal? Again, I don't claim that I can solve the paradox, I merely claim that it wouldn't necessarily be a deterrent from time travel, a process regularily undertaken by verious subatomic particles, all without of them becoming fathermurderers, as I might add. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> I wouldn't go that far. Time is definitely more than the flow of causality. It is generally excepted in every theory I've physics that I've heard of that time is a dimension, although the properties it has may be very different than those we ascribe to it in our daily lives. Pretty soon we might not need to debate this much since we could soon have experimental evidence to differentiate string theory from relativity. <a href='http://www.boston.com/news/nation/articles/2004/04/03/probe_eyes_key_concept_of_physics/' target='_blank'>check it out</a>
for an interesting little brain teaser, time can be measured in meters and distance can be measured in seconds, which of course makes velocities unitless quantities. <!--emo&::nerdy::--><img src='http://www.unknownworlds.com/forums/html//emoticons/nerd.gif' border='0' style='vertical-align:middle' alt='nerd.gif' /><!--endemo--> <!--emo&:D--><img src='http://www.unknownworlds.com/forums/html//emoticons/biggrin.gif' border='0' style='vertical-align:middle' alt='biggrin.gif' /><!--endemo-->
<!--QuoteBegin-Dr.Suredeath+Apr 11 2004, 11:47 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Dr.Suredeath @ Apr 11 2004, 11:47 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> The world and the galaxy is moving at an unimaginable speed. If we're to be teleported, doesn't that mean we're going to popped up 123,233,321 miles away in space?
Unless you can answer this question, do not attempt time travel. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> Nothing some NASA engineers wouldn't be able to compensate for on their lunch break.
First of, sadly (be cool to travel in a DeLorean), Back to the Future is flawed (duh, its Hollywood. I mean, come on, the entire 3rd move could have been 1 hour or less - switch gas tanks, remind 1965 counterpart to get new tank.)
Now, I believe in the so called "worldline theory" more than anything. Now, this states that any action causes a new worldline. Confused? Heres an interactive example:
Hold out two hands. Now snap a finger.
So, why did you do that one, you could have snapped the other. Why did you hold out your arms in the first place, you don't need to hold then out anyway. Why did you even do what I said, anyway?
See, in something seemingly simple as snapping a finger, you have created the possiblities of creating an almost infinite amount of worldlines. So, instead of going back in time, you jump backwards on "worldlines." (Think either John Titor or BTTF part 2, where an alternate time was created. Guess that could explain how Old Biff brought back the DeLorean to the future, eh?)
Another thing to prove this... I quote from JohnTitor.com:
"Imagine your path through time is through a cone. The farther away from the center of the cone, the more differences you will see in the worldline."
I would think of it as traveling in water or space. Can you swim in a perfect line? No. Waves and the movement of other things in the water will push you of course. The same with space travel. Yea, there are correctional boosters and such on the ships, but the pull of gravitational pulls (sun, moon, Earth, etc.) will still pull said spaceship off course. So, apparently the same applies to time travel, as John Titor has said here.
Oh, and debunkin the "grandpa theory"... You go back in time and kill your grandfather. EVEN IF IT WAS ORIGINALLY THE SAME WORLDLINE you would still live, since your going back there creates a new worldline. Sorry Doc Brown! Folks, you can't create a temporal paradox. Alternate worldlines prevent this. The Big G up there thought out his creation really good, didn't he?
Oh, the same goes for the "Billiard Ball" test. Yea, you shoot it into the hole. Once it falls through the hole, it goes back in time an crosses paths with itself, stopping it from going back. New worldline once the billiard ball goes back.
THINK 4th DIMENSIONALLY!
Of course, I could have gotten all this wrong, but oh well, heres my 2 pesos.
Oh, and check out JohnTitor.com or the Anomalies.net Forums for stuff on this. Its pretty interesting.
Oh, by the way, why would you want to go back in time, anyway? Is it really worth it to expend that much energy to change something?
<!--QuoteBegin-Nemesis Zero+Apr 11 2004, 03:18 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Nemesis Zero @ Apr 11 2004, 03:18 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> Maybe you all should keep in mind that 'time' is indeed nothing but the mental construct we use to cope with the flow of causality - which does, as has been recently <a href='http://www.quantumphil.org/' target='_blank'>proved</a> - care diddly squat for chronology. What I'm trying to say here is that just because we can't imagine a solution to the problem - our brains base any kind of assumption about a causal process on its chronology - it doesn't have to be there at all. Who says the universe cares about who your grandfather is? You are there, he is there, energy sums play no role as the universe is for all we know not self-contained, so what's the big deal? Again, I don't claim that I can solve the paradox, I merely claim that it wouldn't necessarily be a deterrent from time travel, a process regularily undertaken by verious subatomic particles, all without of them becoming fathermurderers, as I might add. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> We call it time, because we have to call it something. Without names we have no language. I can call a tube a fahamashanti, but it's still a can. Time is the measured (or measurable) period during which actions, processes or conditions exist based on one's frame of reference.
I'm with Nem and the screaming camera guy though, addign energy, in any amount isn't going to make much of a difference, a human body compared to a star is insignificant. You also have to realize that you're not going to make your body go nuclear, however much you try. Your body contains elements heavier than iron and those are solely created through super nova explosions, as they're inefficient, and take energy opposed to creating it.
If it's to happen, there's much more than a person to be teleported. His clothes, the air around him, the moisture, the floor he's standing on. What will happen to the surround once he get to the past? Will there be a big boom caused by these sudden appearance of this stuffs out of no where? What happen to the air, the atmosphere that's already there?
The world and the galaxy is moving at an unimaginable speed. If we're to be teleported, doesn't that mean we're going to popped up 123,233,321 miles away in space?
Unless you can answer this question, do not attempt time travel. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> One would have to assume that your body and the general sphere where your time travel takes place would replace the spot that you arrive and that the space you occupy would vaporize (unlikely), obliterate the matter that shares its volume (possible, but, there's so much space in atoms, very few would actually do this - or they could just fuse); although, realistically, you're probably not going to be in one posistion to go back in time, and your matter will be replaced or traded with whatever you go through.
We'll never know until/if we do it. You're also correct, that if we time travelled on earth, near a star in one of the galaxy's arms - depending on how long we time travelled - we would end up a significant distance from the earth. That's assuming physical laws like gravity and electromagnetic attraction don't occur during time travel though, which I would doubt (if it were possible).
Still based on our current understanding of physics, the only way you could go fast in time (assuming the existance of theoretic particles) in one case: you hitch a ride on one of proposed sub-atomic particles that moves faster than the speed of light (neutrinos or something), of course, a human would slow down the particle (if it existed, and if it could be obtained), to a point at which it would no longer be going the speed of light.
We also can't obtain the speed of light ourselves, because it would require an infinite amount of energy: the closer to c you get, the more time stretches (seems to slow down) and the more energy you need to move your mass. Which is in fact, one of the properties of light that baffles many people, as photons seem to exhibit mass like properties (but of course, photons are packets of energy, (I took physics and I still don't get how you can have a 'packet' of energy that moves like a physical body but still exhibits wave-like properties...)).
Technically, if you go a substantial fraction of the speed of light, you will go back in time (actually, go slower into the future than other people). An observed occurance with space explortaion was that the astronauts did actually gain a few seconds of life compared to that of everyone on earth. Of course, the downside is, you would never be able to go back in time, and you're basically just living longer (but it would feel the same at your frame of reference).
This keeps dancing around the speed of light, but assume there's another way, through the multiverse (which, coincidently, is becoming a more popular view, but is still widely unaccepted). The idea that the universe is splitting into an infinite number of new universes every infinitely small unit of time (every instant, if you will). Assuming we found a way to get to one of these multiverses (some would assume time takes longer to elapse (you could assume the speed of light is different, to cause time to move slower). In that way, the alternate universe would be in the 'past' (and when you arrived there, it would seem the same as it is here, it's just in relation to our reference point that it goes slower). There you could kill someone perfectly like your relative (except he's not, because he's from a diferent universe). That's about as close as you're going to get.
You could assume that you could use this to go into the future and obtain special documentation about an infinite energy source or something, thus speeding your universe's advancement. Of course, there would be a universe where you failed, where no one wanted to use your plans, where nuclear war erupts, where all the stars in the universe spontaneously explode, where Flayra becomes king of Earth and beats back rabid trekkies, where Han Solo jumps out of a star wars showing - last action hero style, and an infinite number more of probable and inprobable universes.
So with the current human understanding of physics, going slower forward in time would be possible (in fact it has happened), or possibly entering another part of the multiverse (although the multiverse is unproven (although there are many photonic interactions, and afforementioned 'firing stuff through stuff' experiments that suggest that other universes in a multiverse are interacting with our own)).
That doesn't mean I don't wish it were possible though <!--emo&:p--><img src='http://www.unknownworlds.com/forums/html//emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif' /><!--endemo--> . I want to go back in time /cry .
[edit] My disclaimer: I haven't taken physics in a year, but most of this information was accurate (everything is as I remember it, but some details might be minimally off) as to physics knowledge about one year ago (so, maybe the multiverse is more popular now? My physics teacher didn't believe it, but I'm all for the crazy stuff. [edit]
For example, there are some conceptions of time travel which fits Douglas Adams view, in which a change becomes incorporated into the timeline anyway (kind of the reverse of the fatalistic view).
Another example is what I call the Assimov perspective, in which minor changes "Bleed out" changes. For example, taking a rock from 500 million years ago and replacing it a few weeks later (or not at all) will result in a local time change, but in the long term results no change (no three eyed humans as a result of taking that one rock). Yet major changes (like blowing up a sizable fraction of the Earth) will result in a major differential.
Something else of note, until someone can show me a working time machine, I'd hesitate to invite constraints on views, such as the ability to time travel is limited to the invention of time travel, it's better to try and keep a very open mind about this stuff.
Consider the following mathematical examples without explanation and interpret them in relation to time travel.
<!--QuoteBegin-Cronos+Apr 12 2004, 11:38 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Cronos @ Apr 12 2004, 11:38 AM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> the ability to time travel is limited to the invention of time travel,
<!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd--> No, actually its main limiting factor is whether or not it is actually possible. If it is impossible, then no invention on earth (or in space) is every going to change that.
<!--QuoteBegin--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> </td></tr><tr><td id='QUOTE'><!--QuoteEBegin-->Consider the following mathematical examples without explanation and interpret them in relation to time travel.
7 + 8 = 15
8 + 7 = 15
Root 9 = +3 or -3<!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
I have absolutely no idea what you are getting at there. Are you trying to say tht different operations can produce the same result, while the same operation can produce different results?
Comments
And trying to prove 'past'-time travel online is <span style='color:white'>pointless</span>, discussing it just as <span style='color:white'>pointless</span> <!--emo&:)--><img src='http://www.unknownworlds.com/forums/html//emoticons/smile.gif' border='0' style='vertical-align:middle' alt='smile.gif' /><!--endemo--> Paradox's are easy little things. Which makes time travel oh-so fun. There is no correct answer, fella's. Try to concentrate on the more important things, like pipe dreams (Room Temp. Superconductors? DNA Computers? Quantum Computers? Hell, Quantum physics as a whole? ;p )
Oh, a nice couple of paradox's, the first I thought of myself, probably been said before tho.
<span style='color:white'>Don't go O-T.</span>
0- Your grandfather is born
1- Your father is born
2- You are born
3- You travel back into time
4- You attempt to kill your grandfather
S- You succeed
F- You fail
NE- You no longer exist
E- You exist
+1 - You Travel back to one minute past when you left.
-1 - You Travel back to one minute before you left.
S - You stop yourself
FS - You fail to stop yourself
? - Unknown event
N/A - Simpsons Episode #8235-A never aired.<!--c2--></td></tr></table><div class='postcolor'><!--ec2-->
<!--emo&:p--><img src='http://www.unknownworlds.com/forums/html//emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif' /><!--endemo-->
Now:
<!--c1--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>CODE</b> </td></tr><tr><td id='CODE'><!--ec1-->Timeline #1
====0====1====2====3
======4=S -> NE or ?
? ? ? ? ? ? ? "=F==1====2====3
[LOOPS]
<!--c2--></td></tr></table><div class='postcolor'><!--ec2-->
Considering you continue to try, this will loop indefinately until you succeed. Even if you have a 0.000000000001% chance, you'll succeed evetually.
<!--c1--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>CODE</b> </td></tr><tr><td id='CODE'><!--ec1-->Timeline #2
====0====1====2====3
===========4=S -> E
? ? ? ? ? ? ? ? ? ? ? ? ? "=F==2====3
[LOOPS]
<!--c2--></td></tr></table><div class='postcolor'><!--ec2-->
In this, your time machine has screwed up, sending you to a time where your father has been born. You will still exist, as your father still lives. Again, it will loop until you give up or succeed.
<!--c1--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>CODE</b> </td></tr><tr><td id='CODE'><!--ec1-->Timeline #3
[too difficult to display - but it loops until broken]
<!--c2--></td></tr></table><div class='postcolor'><!--ec2-->
This one deals with a looping cycle of events in which you either fail or succeed. Obviously, if you succeed the cycle is broken and if you fail it continues forever.
[Oops. Pressed send WAY too early. Oh well. And this is all guessing that you enter a new dimention for #1+2, otherwise you'd meet yourself each time you went back into time. For #3 you'd almost certainly meet yourself.
Man, do I EVER hate the mechanics of "Time"!]
[Edit 2: Actually i think it's impossible to look at this on a 2D plane (IE a sheet of paper) in it's most complex form; simply because you'd run out of paper trying to cover all the events and variables. I mean, i have 14 variables, and 3 examples, and look at how much space it's already taken! <!--emo&:0--><img src='http://www.unknownworlds.com/forums/html//emoticons/wow.gif' border='0' style='vertical-align:middle' alt='wow.gif' /><!--endemo--> ]
And even if it was possible, nothing will change the past.
The shotgun will jammed. A homeless man will get in the way between grandpa and the gun. You will be run down by a really big St.Bernard. Grandpa tripped a stone and you missed the shot.
Point is, you will never ever hit grandpa in the first place, no matter how hard you try.
No, no. That's not what I'm saying at all.
I'm saying that you just can't prevent that man to go on that plane and die in the crash.
Taxi is not an option. Plane is the only option.
But wouldn't going FASTER than time cause you to end up in the future in stead of the past?
A respected scientist Dr Frank Tipler published plans for a working time machine in 1974:
The machine is too big to be built anywhere on earth, it consists of a huge cylinder of very dense material. When set spinning the Tiper cyclinder creates areas which act as gateways to the past and future. The best shape for a timeship which could use the gateways created by a Tipler Cylinder is disc-like. In other words, similar to a flying saucer.
But wouldn't going FASTER than time cause you to end up in the future in stead of the past? <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd-->
No.
If you go somewhere at a certian speed, it takes 2 hours. If you go twice as fast, it only takes an hour. If you go there fast enough, you arrive at the moment you leave, the journey takes no time at all. If you go faster, you arrive before you left. If you go far enough for long enough, you can travel to any point in the past that you want. The only trouble is, you cannot get back.
Think about it. If man is to be able to time travel in the future, then in our history, there would be recordings of visitors. This right here tells us either a) Time travel is simply impossible for physical beings, or b) Time travel would NOT affect the past, thus paradoxes are not a problem. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd-->
There is a simple answer to this question.
It is because the limits of time travel are this:
You cannot go back farther then when the time travel machine was built.
Remember, a time traveling machine would only go back to it's history. Of course, once it is built, you could fling yourself far into the future and see what's up.
But wouldn't going FASTER than time cause you to end up in the future in stead of the past? <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
No.
If you go somewhere at a certian speed, it takes 2 hours. If you go twice as fast, it only takes an hour. If you go there fast enough, you arrive at the moment you leave, the journey takes no time at all. If you go faster, you arrive before you left. If you go far enough for long enough, you can travel to any point in the past that you want. The only trouble is, you cannot get back. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd-->
Actually, if you go twice as fast, you get there in less than half the time. It's not exactly proportional. The effects aren't really noticable until you go "fast enough," about the speed of light.
So, sending a single photon back in time by about a femptosecond by barely exceeding the speed of light is possible, but it would never happen to a person. You simply won't be able to accelerate them to that speed because of the rediculous amount of energy it would take (+ the engine, ship, and infinitely large amount of fuel they'd have to take). Also, to avoid killing the passenger you'd have to accelerate slowly over the course of about 10 years. And then there's friction...
And, if you wanted to travel back in time at any significant rate (ie, die of old age by the time you got there), you'd have to go several times that speed, if it's even possible.
Going backwards in time? I don't think that's possible.
I'm saying that you just can't prevent that man to go on that plane and die in the crash.
Taxi is not an option. Plane is the only option. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd-->
Ok then the real question how do you know thats its not your fate to go back in time and kill him. Everything being locked into fate and nothing can change doesnt seem to be a very plausible option.
Who says the universe cares about who your grandfather is? You are there, he is there, energy sums play no role as the universe is for all we know not self-contained, so what's the big deal?
Again, I don't claim that I can solve the paradox, I merely claim that it wouldn't necessarily be a deterrent from time travel, a process regularily undertaken by verious subatomic particles, all without of them becoming fathermurderers, as I might add.
That doesn't stand up to common sense or logic. You're talking about traversing time and the actual invention of a time machine ( this is absence of any use ) has no affect on time itself.
The difference between a time machine and photography is that photography is an invention in and of itself and of course cannot exist before it was invented. A time machine, if possible to build, would use something that existed prior to its creation. So there is no reason to even assume that time travel could not go back past the actual invention.
If it's to happen, there's much more than a person to be teleported.
His clothes, the air around him, the moisture, the floor he's standing on.
What will happen to the surround once he get to the past? Will there be a big boom caused by these sudden appearance of this stuffs out of no where? What happen to the air, the atmosphere that's already there?
The world and the galaxy is moving at an unimaginable speed. If we're to be teleported, doesn't that mean we're going to popped up 123,233,321 miles away in space?
Unless you can answer this question, do not attempt time travel.
Who says the universe cares about who your grandfather is? You are there, he is there, energy sums play no role as the universe is for all we know not self-contained, so what's the big deal?
Again, I don't claim that I can solve the paradox, I merely claim that it wouldn't necessarily be a deterrent from time travel, a process regularily undertaken by verious subatomic particles, all without of them becoming fathermurderers, as I might add. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
I wouldn't go that far. Time is definitely more than the flow of causality. It is generally excepted in every theory I've physics that I've heard of that time is a dimension, although the properties it has may be very different than those we ascribe to it in our daily lives. Pretty soon we might not need to debate this much since we could soon have experimental evidence to differentiate string theory from relativity. <a href='http://www.boston.com/news/nation/articles/2004/04/03/probe_eyes_key_concept_of_physics/' target='_blank'>check it out</a>
for an interesting little brain teaser, time can be measured in meters and distance can be measured in seconds, which of course makes velocities unitless quantities. <!--emo&::nerdy::--><img src='http://www.unknownworlds.com/forums/html//emoticons/nerd.gif' border='0' style='vertical-align:middle' alt='nerd.gif' /><!--endemo--> <!--emo&:D--><img src='http://www.unknownworlds.com/forums/html//emoticons/biggrin.gif' border='0' style='vertical-align:middle' alt='biggrin.gif' /><!--endemo-->
The world and the galaxy is moving at an unimaginable speed. If we're to be teleported, doesn't that mean we're going to popped up 123,233,321 miles away in space?
Unless you can answer this question, do not attempt time travel. <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd-->
Nothing some NASA engineers wouldn't be able to compensate for on their lunch break.
First of, sadly (be cool to travel in a DeLorean), Back to the Future is flawed (duh, its Hollywood. I mean, come on, the entire 3rd move could have been 1 hour or less - switch gas tanks, remind 1965 counterpart to get new tank.)
Now, I believe in the so called "worldline theory" more than anything. Now, this states that any action causes a new worldline. Confused? Heres an interactive example:
Hold out two hands. Now snap a finger.
So, why did you do that one, you could have snapped the other. Why did you hold out your arms in the first place, you don't need to hold then out anyway. Why did you even do what I said, anyway?
See, in something seemingly simple as snapping a finger, you have created the possiblities of creating an almost infinite amount of worldlines. So, instead of going back in time, you jump backwards on "worldlines." (Think either John Titor or BTTF part 2, where an alternate time was created. Guess that could explain how Old Biff brought back the DeLorean to the future, eh?)
Another thing to prove this... I quote from JohnTitor.com:
"Imagine your path through time is through a cone. The farther away from the center of the cone, the more differences you will see in the worldline."
I would think of it as traveling in water or space. Can you swim in a perfect line? No. Waves and the movement of other things in the water will push you of course. The same with space travel. Yea, there are correctional boosters and such on the ships, but the pull of gravitational pulls (sun, moon, Earth, etc.) will still pull said spaceship off course. So, apparently the same applies to time travel, as John Titor has said here.
Oh, and debunkin the "grandpa theory"...
You go back in time and kill your grandfather. EVEN IF IT WAS ORIGINALLY THE SAME WORLDLINE you would still live, since your going back there creates a new worldline. Sorry Doc Brown! Folks, you can't create a temporal paradox. Alternate worldlines prevent this. The Big G up there thought out his creation really good, didn't he?
Oh, the same goes for the "Billiard Ball" test. Yea, you shoot it into the hole. Once it falls through the hole, it goes back in time an crosses paths with itself, stopping it from going back. New worldline once the billiard ball goes back.
THINK 4th DIMENSIONALLY!
Of course, I could have gotten all this wrong, but oh well, heres my 2 pesos.
Oh, and check out JohnTitor.com or the Anomalies.net Forums for stuff on this. Its pretty interesting.
Oh, by the way, why would you want to go back in time, anyway? Is it really worth it to expend that much energy to change something?
GG CERN!
Who says the universe cares about who your grandfather is? You are there, he is there, energy sums play no role as the universe is for all we know not self-contained, so what's the big deal?
Again, I don't claim that I can solve the paradox, I merely claim that it wouldn't necessarily be a deterrent from time travel, a process regularily undertaken by verious subatomic particles, all without of them becoming fathermurderers, as I might add. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
We call it time, because we have to call it something. Without names we have no language. I can call a tube a fahamashanti, but it's still a can. Time is the measured (or measurable) period during which actions, processes or conditions exist based on one's frame of reference.
I'm with Nem and the screaming camera guy though, addign energy, in any amount isn't going to make much of a difference, a human body compared to a star is insignificant. You also have to realize that you're not going to make your body go nuclear, however much you try. Your body contains elements heavier than iron and those are solely created through super nova explosions, as they're inefficient, and take energy opposed to creating it.
<!--QuoteBegin--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> </td></tr><tr><td id='QUOTE'><!--QuoteEBegin-->More reason why I think it's impossible:
If it's to happen, there's much more than a person to be teleported.
His clothes, the air around him, the moisture, the floor he's standing on.
What will happen to the surround once he get to the past? Will there be a big boom caused by these sudden appearance of this stuffs out of no where? What happen to the air, the atmosphere that's already there?
The world and the galaxy is moving at an unimaginable speed. If we're to be teleported, doesn't that mean we're going to popped up 123,233,321 miles away in space?
Unless you can answer this question, do not attempt time travel. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
One would have to assume that your body and the general sphere where your time travel takes place would replace the spot that you arrive and that the space you occupy would vaporize (unlikely), obliterate the matter that shares its volume (possible, but, there's so much space in atoms, very few would actually do this - or they could just fuse); although, realistically, you're probably not going to be in one posistion to go back in time, and your matter will be replaced or traded with whatever you go through.
We'll never know until/if we do it. You're also correct, that if we time travelled on earth, near a star in one of the galaxy's arms - depending on how long we time travelled - we would end up a significant distance from the earth. That's assuming physical laws like gravity and electromagnetic attraction don't occur during time travel though, which I would doubt (if it were possible).
Still based on our current understanding of physics, the only way you could go fast in time (assuming the existance of theoretic particles) in one case: you hitch a ride on one of proposed sub-atomic particles that moves faster than the speed of light (neutrinos or something), of course, a human would slow down the particle (if it existed, and if it could be obtained), to a point at which it would no longer be going the speed of light.
We also can't obtain the speed of light ourselves, because it would require an infinite amount of energy: the closer to c you get, the more time stretches (seems to slow down) and the more energy you need to move your mass. Which is in fact, one of the properties of light that baffles many people, as photons seem to exhibit mass like properties (but of course, photons are packets of energy, (I took physics and I still don't get how you can have a 'packet' of energy that moves like a physical body but still exhibits wave-like properties...)).
Technically, if you go a substantial fraction of the speed of light, you will go back in time (actually, go slower into the future than other people). An observed occurance with space explortaion was that the astronauts did actually gain a few seconds of life compared to that of everyone on earth. Of course, the downside is, you would never be able to go back in time, and you're basically just living longer (but it would feel the same at your frame of reference).
This keeps dancing around the speed of light, but assume there's another way, through the multiverse (which, coincidently, is becoming a more popular view, but is still widely unaccepted). The idea that the universe is splitting into an infinite number of new universes every infinitely small unit of time (every instant, if you will). Assuming we found a way to get to one of these multiverses (some would assume time takes longer to elapse (you could assume the speed of light is different, to cause time to move slower). In that way, the alternate universe would be in the 'past' (and when you arrived there, it would seem the same as it is here, it's just in relation to our reference point that it goes slower). There you could kill someone perfectly like your relative (except he's not, because he's from a diferent universe). That's about as close as you're going to get.
You could assume that you could use this to go into the future and obtain special documentation about an infinite energy source or something, thus speeding your universe's advancement. Of course, there would be a universe where you failed, where no one wanted to use your plans, where nuclear war erupts, where all the stars in the universe spontaneously explode, where Flayra becomes king of Earth and beats back rabid trekkies, where Han Solo jumps out of a star wars showing - last action hero style, and an infinite number more of probable and inprobable universes.
So with the current human understanding of physics, going slower forward in time would be possible (in fact it has happened), or possibly entering another part of the multiverse (although the multiverse is unproven (although there are many photonic interactions, and afforementioned 'firing stuff through stuff' experiments that suggest that other universes in a multiverse are interacting with our own)).
That doesn't mean I don't wish it were possible though <!--emo&:p--><img src='http://www.unknownworlds.com/forums/html//emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif' /><!--endemo--> . I want to go back in time /cry .
[edit] My disclaimer: I haven't taken physics in a year, but most of this information was accurate (everything is as I remember it, but some details might be minimally off) as to physics knowledge about one year ago (so, maybe the multiverse is more popular now? My physics teacher didn't believe it, but I'm all for the crazy stuff. [edit]
So far there have only been a few kinds of Time Travel discussed here.
1. Impossible due to matter/laws of physics (etc)
2. The "Fatalistic" kind in which time in unchangable, but observable (Gun jams etc)
3. Multiverse (extradimensional, "worldline", alternate timelines etc etc etc)
However, there are others.
For example, there are some conceptions of time travel which fits Douglas Adams view, in which a change becomes incorporated into the timeline anyway (kind of the reverse of the fatalistic view).
Another example is what I call the Assimov perspective, in which minor changes "Bleed out" changes. For example, taking a rock from 500 million years ago and replacing it a few weeks later (or not at all) will result in a local time change, but in the long term results no change (no three eyed humans as a result of taking that one rock). Yet major changes (like blowing up a sizable fraction of the Earth) will result in a major differential.
Something else of note, until someone can show me a working time machine, I'd hesitate to invite constraints on views, such as the ability to time travel is limited to the invention of time travel, it's better to try and keep a very open mind about this stuff.
Consider the following mathematical examples without explanation and interpret them in relation to time travel.
7 + 8 = 15
8 + 7 = 15
Root 9 = +3 or -3
<!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd-->
No, actually its main limiting factor is whether or not it is actually possible. If it is impossible, then no invention on earth (or in space) is every going to change that.
<!--QuoteBegin--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> </td></tr><tr><td id='QUOTE'><!--QuoteEBegin-->Consider the following mathematical examples without explanation and interpret them in relation to time travel.
7 + 8 = 15
8 + 7 = 15
Root 9 = +3 or -3<!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
I have absolutely no idea what you are getting at there. Are you trying to say tht different operations can produce the same result, while the same operation can produce different results?
root 9 is +3 <i>and</i> -3, both at the same time