Time travel?

[TuxDave]

Originally posted by: Farvacola
Ive read that time travel is possible when the flow of time is viewed as a large u shape. At some point in the gap between the two ends, there is a point,
or path of conveyance in which it would be mathematically possible to go back or forward in time. This path is more commmonly known as a worm hole
and is a flux in the space time continuim. The question is, does anything really hold water when it is theoretical and not practical? Only time will tell.

"Imagine time to be like a string with positive and negative time on either end. It is very possible that these ends are connected to the same point, so if we need to go back in time, we just need to accelerate very fast towards one end and instantly appear on the other end. But there's another way. Imagine then taking that string and bundling it up into a pile. Now every point in time is touching another point in time you can just take a 'leap' from one point in time to another."

I know I butchered it... but that's what Quantum Leap basically said... or something like that.

 

[RampantAndroid]

Well, time travel cannot be proven to be possible or not....take the speed of sound, or light for example: there is an asypmtote right before you can break the speed of sound, hence "sonic boom" this is caused by the air dragging brhind the plane, and this only occurs when breaking the speed of sound. However, this "boom" stresses the plane.....so this opens a question: can we build something to withstand the forces that would be caused by the speed of light? There is an asymptote there too!

We can only find out by trying.....however, we have theories, and the ability to test when striving for the speed of light.....how would one go back in time? Perhaps we should look to relativitey:

two people, one on a train going 60 MPH, and he is watching a grandfather clock's pendulum swing back and forth, lets say its arc encompasses 1.5 feet...

Second guy on the train platform, if he could see that pendulum move, one swing from side to side would take much longer, and since 1 second is defined by the swing of the pendulum, to him, the train's time is moving SLOWER. To the guy on the platform, 5 seconds could be equal to 1 of the guy on the train, because the pendulum would take 5 times as long to make one arc (not mathematically correct here, however, based on relativitey, I am "correct")

What if we COULD go faster than light.....lets go 140 lightyears out from earth, and look back at it....if we could take the image we see of earth 140 lightyears away, you would be able to see what civil war (US Civil war for all you ppl not living in the US) really looked like! Technically, you could say you went back in time.......apply the grandfather clock analogy to the faster than light travel....time would slow down there two.....or would it?

I'll stop here because I am tired and need some sleep, and nobody is reading my long post anyway I'll bet!!

One last note: go look at any star....say beetlejuice....did you know beetlejuice may have already gone supernova/created a black hole....and we wouldn't know it for thousands of years, it takes that long for the light to reach us!

 

[DarkSarkas]

This whole thread is moot. We have yet to reach a true understanding regarding the nature of time, and therefore any concept of time travel cannot be explored or hypothesized.

I hope soon we know enough to ask questions that will take us where we need to go

 

[mmcdonalataocdotgov]

Time Travel Is Not Possible Pragmatically.

Proof: If time travel had ever been possible, we would always have known about it, since time travellers would have brought us the information - eventually. It would be inevitable that once time travel was known in one time, it would be known in all times (method, mode, theory, etc.)

Since we do not know how to travel in time, we will never know (never knew) how to travel in time.

 

[Jeff7]

Originally posted by: mmcdonalataocdotgov
Time Travel Is Not Possible Pragmatically.

Proof: If time travel had ever been possible, we would always have known about it, since time travellers would have brought us the information - eventually. It would be inevitable that once time travel was known in one time, it would be known in all times (method, mode, theory, etc.)

Since we do not know how to travel in time, we will never know (never knew) how to travel in time.

Unless those who discovered time travel either destroyed themselves in some further experiment, or else there was a temporal war, in which the future wipes itself out.

 

[DDG]

Time travel is something of an oxymoron since time is a human conceptualization. We created the concept to essentially quantify changes in the world and gave it the name time. Since we experience reality as human beings bound to finite senses we ponnder the idea of traveling in time.

 

[RampantAndroid]

Perhaps time travel can only be used to go into the furute, and the past cannot be altered....or perhaps, for those who do not believe in pre-destination or fate, perhaps you can only go BACK in time, since the furutre is unkown...either way, this is paradoxial.

Or perhaps the universe is structured in adifferent way....every time we make a choice, we create new timelines, one where we say "yes" and one where we say "no", and every time we make a new choice, a new timeline is created for each possibility, thus there are infinite timelines.

 

[JF0603]

everyone knows that the junction of the space time continuum is november 5th 1955

 

[cy7878]

Look, The thread isn't to look for scholarly (or foolish) opinions on whether time travel is or is not possible.

I know mathematically it is because a professor of mine in college worked on this and would have explained it to me if he had the time. It is possible in theory, it is the theory I am after.

Many things are possible in theory but not in practicality because we don't have the resources to make it happen. So please, refrain from providing opinions unless you know what I am asking.

This is afterall, highly technical.

 

[CycloWizard]

What if we COULD go faster than light.....lets go 140 lightyears out from earth, and look back at it....if we could take the image we see of earth 140 lightyears away, you would be able to see what civil war (US Civil war for all you ppl not living in the US) really looked like! Technically, you could say you went back in time.......apply the grandfather clock analogy to the faster than light travel....time would slow down there two.....or would it?

Einstein proved that the speed of light is constant regardless of your point of observation using mathematics, and he was pretty good at math. That doesn't mean he's right, but I have yet to read anything proving any of his highly regarded theories wrong. "Relativity: The Special and the General Theory, A Clear Explanation That Anyone Can Understand" by Einstein give a pretty good discussion on the subject that most people with a basic physics/math background will be able to understand.

Originally posted by: mmcdonalataocdotgov
Time Travel Is Not Possible Pragmatically.

Proof: If time travel had ever been possible, we would always have known about it, since time travellers would have brought us the information - eventually. It would be inevitable that once time travel was known in one time, it would be known in all times (method, mode, theory, etc.)

Since we do not know how to travel in time, we will never know (never knew) how to travel in time.

"Aliens."

There's another book out there by a physics PhD from Stanford that discusses this subject. I haven't read it yet, but I picked it up for $4 at a used book store. "Faster Than Light: Superluminal Loopholes in Physics" by Nick Herbert. Short paperback and probably worth the read if you're genuinely interested.

 

[ReiAyanami]

Proof: If time travel had ever been possible, we would always have known about it, since time travellers would have brought us the information - eventually. It would be inevitable that once time travel was known in one time, it would be known in all times (method, mode, theory, etc.)

why would they travel to this time? they might travel to some year in the future that is still the past to them. in fact, they keep travelling back in time just to make movies about robots and governators

time is generally regarded as the 4th dimension, and all first 3 dimensions are traversable in both directions, so why not the 4th as well. although quantum scientists say there are 10-12 dimensions total but then things get real loopy.

 

[tphss]

Maybe it's possible in the mathematical theory, but physically, an object could see something before it happens (travel forward in time) only if it can travel faster then the speed of light, and no object that has a mass can travel the speed of light or faster. This makes it impossible, atleast for today's sience.
But, no one belived 200 years ago we would be able to fly 450 people in a plane traveling close to 1000km/h, but for some reason I think this thing will be a bit more complicated and near impossible.

 

[everman]

If it is possible to travel reverse through time, either whoever can will "never" make it known in our own past, or else we would already know about it.

I think the only responsible way to time travel would be as an observer only. I think if someone did have the capability to traverse time, would it also mean that they never did destroy themselves in the process? Because if you did for example you cannot kill your parents in the past because the act of doing so would cause you to not exist.

I guess my basic idea is it would be possible if you could avoid every paradox involved.

 

[GMElias]

Well, since time is just a continuum and not really a constant (the only "constant" is c, or the speed of light), we can, by means of special relativity, "shift our location in time." And really, time IS location because it is a measure, per se, of the speed of light. Anyway, I am not sure if we can go back in time if that is your question because we would be in a different space continuum, or rather, a different position. But it is physically possible, mathematically, to slow your metabolical rate (or increase your lifespan) by travelling near the speed of light. The only trouble is this: as soon as your acceleration nears the speed of light, or let's say, 0.1 x the speed of light (c), then, your mass invariably increase (I forgot if there is direct 1:1 proportion, or something else...I used to know this when I studied phsyics more seriously!)...anyhow, as soon as your mass increases, the amount of energy needed for acceleration increases. So, it become a never-ending cycle and therefore, a "body" of mass X can never reach the speed of light because the mass would approach infinity. SO, to actually travel the speed of light, you would need to have virtually (I am not sure how "virtual" now that science is finding things like quarks that have some mass because they have integer spin, or have-integer spin, etc...but I am not caught up on all this)...anyway, approaching the speed of light is for all intent and purposes, impossible, so have a human travel through time is sort of a paradox as well.

Anyway, just my two cents worth...if I am off my rocker, let me know. I wasn't a physics major (biology and music instead), but I did study fairly high level physics, math, etc. I would suggest reading Stephen Hawking (non-fiction) and some Piers Anthony (fiction...seriously, he has an interesting series that deals with this topic to a degree).

Cheers,
Elias

 

[wseyller]

I don't think time travel to the past will ever happen. If it did imagine the time travelers from the future coming to our present or past and imagine all the ways that they could screw things up. It it would ever happen we probably wouldn't be here right now or someone in the government would of figured it out by now that time travelers were coming here and they would have their technology and then we could time travel and screw past events up.

 

[GMElias]

quote from wseyller
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I don't think time travel to the past will ever happen. If it did imagine the time travelers from the future coming to our present or past and imagine all the ways that they could screw things up. It it would ever happen we probably wouldn't be here right now or someone in the government would of figured it out by now that time travelers were coming here and they would have their technology and then we could time travel and screw past events up.
__________________

sorry pal...I hate certain mistakes in grammar...it should be would have.

Anyway, you do make an interesting point otherwise. If people could travel in time in OUR future, why haven't they visited us? Or perhaps they have (Denis Rodman...just kidding!).

-Elias

 

[User1001]

Originally posted by: imgod2u
Sure it is. All you need is a flux capacity, a Delorean that's going up to 88 mph and 1.21 gigawatts of electricity.<BR><BR>But in all seriousnss, there is a working theory of timetravel in the way of wormholes. However, to produce such a thing would be pretty drastic.

didn't stephen hawkings take back his ideas wormholes?

 

[GMElias]

don't know...I know Stephen Hawkings has come out with some new ideas. There is also another great proessor at Princeton (I believe)...the "father" of the super-string theory, who might have some ideas on this topic, and other dimensional travel. Anyway, a lot of good books out there. Stephen Hawking is still one of my favorite thinkers of the 20th-21st centuries!
Cheers,
Elias

 

[Genx87]

I thought there is at least one or two theories on blackholes that theorize at the event horizon you would be able to freely flow in time.

I know it isnt mathematical but of course we would probably never know either due to the gravitational forces.

Also I am just a regular joe who really knows jack squat about this but likes to read what others have to say hehe.

 

[gsellis]

Stephen Hawkings finally realized that the event horizon theories were just flights of fantasy. In the end, you just become stellar mass. The answer was obvious, it just needed to be gleaned. As for time travel, just another flight of fancy. Time is "is", "was" and "will be". Time travel to the past assumes that "will be" can be "was". That +2 equal -2. Time travel fiction is my favorite, but the reality is like the black holes. No wonderful fantasy about travelling to the past as the event occurred and you cannot get back to it.

Evidence? We humans are such meddlers. Do you think that society removed all of the sociopaths that would just have to go back and change something? Security is so good that they could prevent it? No, it just means either that the earth does not exist in the future or time travel does not happen. Hey, the changes branch! Just a figment to resolve the paradox of why we don't see change. We humans are so creative.

 

[everman]

Hawking said that according to string theory, information is not destroyed when put into a black hole. That is if a black hole consumed a star, and you had some way to observe the contents of this black hole, you would be able to determine everything about that star because information about it is not destroyed at the string level.

Somehow this relates to wormholes not able to be used for time travel...I think.

Hey maybe some day we can use wormholes as mass data storage devices?

 

[Chaotic42]

Kip Thorne said that time travel to the past is possible in a way.

Bear with me, I may have part of this incorrect (it's been a long day):

You'd have to take a worm hole, somehow keep it open for a significant amount of time (which from what I've heard may be impossible), place one end at A, then place the other end B.

B (or A, but let's say B) should be a spaceship, but anything will do.

As B travels about, it's time will differ from the time at A. A spaceship is a good thing to use, because it can actually travel fast enough for there to be a noticeable difference in time.

Anyway, B travels along at some speed. Let's say that 1 hour has passed at B. A, on the other hand, has experienced a year of time. Someone at A could walk through the hole and arrive at B with their spaceship pilot captain friend being one year younger than they are.

This would make it possible in a manner of speaking, but you couldn't just arbitrarily go back billions of years.

 

[everman]

Originally posted by: Chaotic42
Kip Thorne said that time travel to the past is possible in a way.
[....snip....]

It kind of sounds like they're creating a tunnel via time dilation? The side traveling faster is traveling slower in time from the perspective of the slower refrence point. But this type of thing requires traveling very close to the speed of light.

 

[Chaotic42]

Originally posted by: everman
It kind of sounds like they're creating a tunnel via time dilation? The side traveling faster is traveling slower in time from the perspective of the slower refrence point. But this type of thing requires traveling very close to the speed of light.

Yep. It also requires lots of exotic material to hold the wormhole open, if that's even possible.

Edit: Here is an interesting link.

 

[gsellis]

There is this old economics joke...

A mathematician, physicist, and an economist are stranded on a desert island. The only food they have is three boxes of canned baked beans. No rocks, no way to open them.

The physicist says, "hey, we could build a fire, and I can calculate where we need to put the cans in the fire so that the tops blow off."

The mathematician smiles and says, "Great, I know some distributions I can run and we can calculate where to put leaves to catch all of the beans as they fly out!"

The economist shakes his head, "you guys are doing this all wrong. Just assume we have a can opener."

So, let's assume we have a wormhole grins, ducks, runs.