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darkvenusian
2004-Aug-02, 03:08 PM
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Hello, I just joined this forum, although I have looked at the website before. I was wondering if anyone had any new info about time travel, and any progress made in making it less of a theory and more of a reality. Any links/ first hand info would be greatly appreciated! Thanks!


Dark :)

StarLab
2004-Aug-02, 03:24 PM
Welcome to the Forum, Daven!
I hardy think we have made any progress of that sort, but if we did the gov't's keeping it secret from us at Area 51. Your best bet is to be hoping that a member Ziggy is soon to read this post, because we all suspect he is building a time travel machine in his backyard. :lol:

galaxygirl
2004-Aug-02, 03:51 PM
Welcome to the forum!

Here are some links I found that have some info regarding time travel:

Nova- Time Travel (http://www.pbs.org/wgbh/nova/time/)

How Time Travel Works (http://science.howstuffworks.com/time-travel.htm)

imported_Ziggy
2004-Aug-02, 04:50 PM
WARNING_ ANY INFORMATION REGARDING BACKYARD PROGRAMS IS HIGHLY CLASSIFIED TO ANY PERSONAL WITH LOWER THAN LEVEL 6 CLEARENCE_ DEADLY FORCE IS AUTHORIZED AGAINST ANY PERSON(S) THAT ENDANGER BACKYARD SECURITY_ ALL PERSONS THAT VIOLATE THESE RESTRICTIONS WILL BE INCARCERATED BY THE HIGH COURT OF PLUTO_

Spacemad
2004-Aug-02, 09:20 PM
Your links are very interesting, Galaxygirl, I especially like the link to "How things work"! :)

As for time travel who needs it when with an instant messaging programme you can sit at home & communicate with your past, present & future!

I have been doing so for the last few weeks - I have conversations with folk from Australia (in my future - by about 8-9 hours), with folk here in the UK, where I live (my present) & with folk in the USA (my past - by about 5-6 hours) & all of us talking to each other in real time! (& at the same time!)

How´s that for time travelling? :P

kodakball
2004-Aug-02, 11:03 PM
Here is an interesting article about time travel, in a news paper
http://english.pravda.ru/science/19/94/379...experiment.html (http://english.pravda.ru/science/19/94/379/12190_experiment.html)

astromark
2004-Aug-03, 12:58 AM
No, No, No. It can not be. Call me old and starched but think it through.
If, as you sit there reading this you consider that moment comming... its here. Its gone. Now its history... and thats it. Finished.
Well not completly... IF you were to travel at above the speed of light, away from where you are, fast enuff to get infront of that image as it reaches you at the speed of light you would see it again. This will I suspect never be posable. Go buy a vidio camera, Its easyér. then you can record the past. for the future.. Try this idea... think of space as a limitless void. thats close to what it is. Its got some stuff woffling about in it. we are some of that stuff. If we could zoom across the universe in any direction you like, for as long as you like, at speeds unthought of. At any point you arrive at, in space and time. That is the time there, now, at that moment. You can not change that. Norr would you want to... Traveling faster or slower would change the time you arrive, and thats it. All finito, fin, finished
You can not time travel forword... as it hasent happened yet.
and time travel back. No. cos it has allready happened.
We are stuck in this reality ...

DarkChapter
2004-Aug-03, 03:45 AM
Why I dont think we will travel faster than light.

When you reach the speed of light, the bottom line of the equation in your relativity formula becomes 0. so you have infinite mass. Having infinite mass would mean that you exert infinite gravitational force uniformly on all points in the universe, which will then accelerate towards you infinitely quickly, hence the instantaneous collapse of the universe, a joyus occasion for all.

David S
2004-Aug-03, 04:58 AM
Having infinite mass would mean that you exert infinite gravitational force uniformly on all points in the universe

Actually, while mass does increase as you approach the speed of light, gravity is determined by the objects rest mass only. So even though your mass increases, your gravity doesn't. Otherwise you would have some people moving in certain reference frames seeing planets collapsing into black holes (since they see themselves as stationary and the planets zooming past them)




You can not time travel forword... as it hasent happened yet

It's happening right now. I'm traveling into the future at the rate of one hour for every hour passing by on earth. Thanks to general relativity, however, I can change that rate. If I where to travel at 99% the speed of light, I would travel into the future at the rate of one hour for every 7 hours passing on earth. Which means by the time I got done, very little time would pass by for me and a lot of time would pass by for the earth, meaning I could essentially travel into the future by slowing down the rate time passes for me.

Unfortuantly, I couldn't go backwards in time to when I started, so once I reach the future I'm stuck there.

rahuldandekar
2004-Aug-03, 12:11 PM
I found this article - Time Travel (http://en.wikipedia.org/wiki/Time_travel).

From Astrowannabe's post :

It's happening right now. I'm traveling into the future at the rate of one hour for every hour passing by on earth. Thanks to general relativity, however, I can change that rate. If I where to travel at 99% the speed of light, I would travel into the future at the rate of one hour for every 7 hours passing on earth. Which means by the time I got done, very little time would pass by for me and a lot of time would pass by for the earth, meaning I could essentially travel into the future by slowing down the rate time passes for me.

Unfortuantly, I couldn't go backwards in time to when I started, so once I reach the future I'm stuck there.

Maybe that's how grandfather paradoxes can be avoided, and Time travel be allowed. Any more improbablities?

StarLab
2004-Aug-03, 05:16 PM
Think about the following: when the future becomes the present, it will be the present for just a moment before becoming the past. The past will always be the past, even if someone invents a time travel machine to go live in the past. And the present is NEVER unchanging. Each possible moment in the future will one day be the present. This is not relative, it is not exponetial, it is a steady path of time that I prefer we leave uninterrupted. I prefer to learn from my mistakes - not avoid them.

lswinford
2004-Aug-03, 08:14 PM
I like time travel. I especially like it at night, with a comfortable clear night (no bugs). I can sit and watch the universe march on its way as I simultaneously view light that has traveled a few dozen years to catch my eye and untold millions, if not billions, of years to converge on the same spot.

Time is a forward vector that is definitely relative. My younger relatives constantly share their observations that it moves very slowly. My older relatives relate that it moves much too quickly.

Time, to others, however, stands still until we move through it.

I just hope that when it comes time for my car to stall that it is not the time when it is a speeding truck's time to be where I am at. Then it shall be time for me to discover a new plane of existance, or is that a truck bumper, which shall propel me beyond where I would have otherwise been. Then, if my faith is correct, I will be able to ask the One who made time, but I probably won't be able to tell you until it is your time, when you can ask for yourself.

WizardWayne
2004-Aug-06, 08:27 PM
Originally posted by DarkChapter@Aug 3 2004, 03:45 AM
Why I dont think we will travel faster than light.

When you reach the speed of light, the bottom line of the equation in your relativity formula becomes 0. so you have infinite mass. Having infinite mass would mean that you exert infinite gravitational force uniformly on all points in the universe, which will then accelerate towards you infinitely quickly, hence the instantaneous collapse of the universe, a joyus occasion for all.
Einsteins equation in the relativity formula only prevents travel AT THE SPEED OF LIGHT. That's when you get a zero in the denominator. Dividing by zero would be BAD.

Einsteins relativity equations DO NOT specifically prevent travel at faster than the speed of light. The denominator becomes a negative number and just what that means isn't clear (best guess: that you move BACKWARDS through time).

But, you ask, if I can't go AT the speed of light, how can I surpass it? It's called tunnelling, moving from one allowed location (speed, energy, etc, etc) to another through a barrier that you can't be in. Think of it as being in your house (which is allowed) and you want to be outside your house (which is also allowed) but you want to go through the brick wall (which is not allowed). With luck and quantum mechanics you can tunnel right through your brick wall. In fact, electrons are doing this millions of time every second inside your computer, allowing you to read this message.

Algenon the mouse
2004-Aug-06, 09:36 PM
There is a great article in "Discover Magazine" about Einstein and his theories. his theories allow time travel, we just do not have the technology to do it right now. If you make a large heavy rotating cylinder that is a light year long, it should distort space and time around it allowing a person to travel forwards and backwards in time by circumnavigating it. Maybe we can ask Bill Gates to build one.

There are three main concepts about time that you can look up:

Spacelike time: (is it three dimensions or four?)

Arrow of time: the relationship of phenomena where time is supposedly irreversible.

Flowing time: This deals more with quntum theory. "We are only aware of a part of time, not one single part.


I hope this helps..

David S
2004-Aug-06, 09:38 PM
Einsteins relativity equations DO NOT specifically prevent travel at faster than the speed of light. The denominator becomes a negative number and just what that means isn't clear

Actually, with Einsteins equations at speeds greater then the speed of light you are forced to take the square root of a negative number, which is also very bad for mathmatics.

The bottom of his equations looks like this:

sqr(1-(v^2/c^2)

So if v>c, then v^2/c^2 will be greater then 1, which will result in the square root of a negative number, which is undefined.

Guest
2004-Aug-07, 10:47 AM
Actually, that will result in imaginary numbers and what it means is not clear. It doesn't become undefined.

rahuldandekar
2004-Aug-07, 10:48 AM
That was me, forgot to log in.

eburacum45
2004-Aug-07, 02:44 PM
The usual way of travelling backwards in time is by using a pair of wormholes.

First you take one end of a wormhole at relativistic speed to another star, this will result in a time difference between the ends due to time dilation. Iif you then repeat this move in the opposite direction

This is all explained in Galaxygirl's link
http://science.howstuffworks.com/time-travel.htm

but what is not explained is the fact that time travel is very very dangerous, and would probably destabilise the Universe by destroying causality;

this is my anti-time travel rant here...
http://www.orionsarm.com/intro/WhyNoTimeTravel.html

it turns out that wormhole theories tend to incorporate a time-travel defeating clause; this can either be a kind of event horizon, which stops a wormhole becoming a time machine-
this event horizon has a name- the Cauchy horizon.

Another way of preventing wormholes becoming time machines is the sudden flux of virtual particles which suddenly appear, travelling round and round the closed timelike curve in a virtual and instantaneous racetrack; this sudden burst of radiation destabilises and destroys the wormhole.

So the universe conspires to prevent paradoxes, and you can never kill/become your own granfather before your father is conceived.

Algenon the mouse
2004-Aug-07, 06:47 PM
I know that wormholes are the popular theory, but it really has not pratical use as of yet since even a macrosopic body would be crushed out of existence by the energies in a wormhole. They also tend to be like one way street through an unknown city, you have no idea where the hell you would wind up.


Maybe in the future...

eburacum45
2004-Aug-07, 07:09 PM
That is not the way wormholes are used in this thought experiment;
first you find a wormhole which has both its mouths close to each other; then you put one mouth in a spaceship and take it to a distant star, keeping the other one near Earth;

when you get the wormhole to the destination you inflate it with 'negative energy' which stops it collapsing and crushing you.

The real difficulty is finding a wormhole, and manufacturing negative energy, which only exists in tiny amounts.

(don't get it confused with antimatter- negative energy is totally different)

Algenon the mouse
2004-Aug-08, 06:29 PM
So exactly what would you say negative energy is then? I am curious..

Since wormholes are suppose to be the line from which mini blackholes are connected, it would interesting to see what kind of force could keep one from crushing you. I have not heard this before.

Guest
2004-Aug-08, 07:53 PM
Negative energy is the opposite of energy; add negative energy to a system and the energy decreases. This is most commonly enncountered in the theory ogf black hole Hawking radiation; as you know, a virtual particle pair is created at the event horizon, and the negative particle falls into tthe hole, while the positive particle is emitted.

Most people think that the particle that falls into the Black hole is antimatter- I certainly did;
it isn't.

No; it is negative energy, and it causes the black hole to reduce in total energy and shrink.

Negative energy has negative gravitatonal pull, and could hold open a wormhole; real physics types call negative energy 'exotic energy' and quantify it in terms of something called the averaged null energy condition (ANEC).


Here is Matt Visser talking about it.
http://cabinet.auriol.free.fr/Documents/pa...ie/trou-ver.htm (http://cabinet.auriol.free.fr/Documents/parapsychologie/trou-ver.htm)

eburacum45
2004-Aug-08, 07:55 PM
Sorry; didn't realise I wasn't logged in.

lswinford
2004-Aug-09, 08:45 PM
Now which StarTrek franchise am I supposed to use to follow this wormhole discussion in? And, of course, there is a space-warp field that protects the craft and its contents, plus their artificial gravity and inertia-dampeners. I can hardly wait (I guess I'm still "not thinking fourth-dimensionally" yet, oops, that was another).

eburacum45
2004-Aug-13, 08:06 PM
Star Trek get the wormhole theory quite wrong; they have the wormhole opening and closing; well, it seems likely that once it closes it is gone. Wormholes are precious things- you don't want to lose them.

Also Star Trek (and Babylon 5) wormholes are disk-like objects, or whirlpools;

the special effects people look at the diagrams and think a wormhole looks like a funnel. This is incorrect.

As a wormhole is a three dimensional flaw in space-time, it should be spherical;
at the very least a spheroid (like an M+M).

You can enter a wormhole at any angle, and as long as you avoid the 'throat' (where it gets narrower) you will get to the other end.

rrdude
2005-Mar-31, 02:06 AM
i dont understand how you could use worm holes to travel through time. I thought in theory they were created when two masses collide punching a hole per say through space to their respected locations. thus making it possable to move quickly between the two objects but not auctuly moving through time its self.

-rrdude