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How to Build a Time Machine
frank249 writes "The September issue of Scientific American has an article discussing the possibility of time travel. They say that it wouldn't be easy, but it might be possible. It could be a while until we can expand worm holes and tow them to a neutron star but didn't someone say that if it is possible it will happen. If it is impossible it will just take a little longer."
I move we call for a slashback in a few hundred years when this might be possible. ;-)
Wouldn't the best way to speed up things for this be to leave a post-it note stuck in the files saying "when this is finally invented, please travel back to August 24, 2002AD and provide the HOW-TO."
--
Todd
Quick lesson in physics for those that don't want to read the article...
Time travel. Possible? Yes. It happens relativly speaking every day.
When you get onto an airplane you slow down in time. To say this simply. The faster you go, the slower time moves around you. This was confirmed back in the 1970's using atomic clocks. Although this isn't exactly time travel it's called time dilation which is a product of the general theory of relativity.
A quick little reference for those not familar with Relativity is a set of lecture notes from a basic astronomy class in U of Oregon.
For a little more in depth reading I'd look into buying The Large Scale Structure of Space-Time by Stephen W. Hawking. Or for those that are sadistic you can read Quantum Field Theory in Curved Spacetime and Black Hole Thermodynamics. That is a collection of lectures from the University of Chicago. Although good in a sense of understanding relativity it kinda takes a tagent into the debate about light being a particle or a wave argument.
Of course, this induces the potential for paradox, causing great cosmological and philosophical consternation. I don't know what will happen if/when someone goes backwards through time, but here's some ideas:
- The universe forks in two when a paradox is induced.
- The universe forks in two at the instant the traveller enters history (because at a micro-level, paradox is induced as soon as they appear).
- Paradox induces a cascading feedback loop of self-modifying universes (each inducing a time-traveller who goes back and causes another chage) until the sequence halts with a universe in which time travel is not developed. My bet is that if time-travel is possible, then this is what has happened, because there is no evidence of time travel.
Forward time travel is of course possible right now, requiring only some patienceCrispin
----
Crispin Cowan, Ph.D.
Chief Scientist, WireX Communications, Inc.
Immunix: Security Hardened Linux Distribution
Available for purchase
is first outlined by physicist Kip Thorn and widely accepted by the scientific community as a real possibility. It is a method which utilise the ability of keeping worm holes open and high speed travel IIRC.
:)
Black Holes and Time Warps: Einstein's Outragous Legacy by Kip Thorn is perhaps one of the best science books I read, though I didn't really read that many of them.
geek page at KY speaks
Wear weird clothes (not weird in the everyday weird people sense, but truly out of place). Walk up to someone (inventing an accent is fun) and ask them what year it is. When they say, puzzled, "2002", get a huge smile and dance a future dance away yelling "it worked, it worked!"
Fun to confuse people with.
Just as fun: Dress up like a hippie or something else interesting from the past and change everything accordingly to the past.
Crispin
----
Crispin Cowan, Ph.D.
Chief Scientist, WireX Communications, Inc. [wirex.com]
Immunix: [immunix.org] Security Hardened Linux Distribution
Available for purchase [wirex.com]
Oooo! Everyone check out the big brain on Crispin!
You're using her as bait, Master!
did i get first post?
no, but perhaps someday you can go back in time and get it.
I believe that travelling to the past would merely let us perform certain travelling at speeds faster than light.
...
.. quirks of worthy pursuit.
...
Or, put another way, the time required at maximum velocity to return to your point of origin is at least the amount of time you travelled back in time. I believe you must sacrifice time or sacrifice position.
Position may or may not be in the way we expect; I suspect it is based upon your "depth" in the gravitational field, and as such, you would travel towards or away from heavy celestial bodies, such as the sun. Travelling towards them requires velocity. By the same token, you can temporally return to the beginning of the universe if you travel far enough away from the centre of it (assuming that the gravitational "depth" continues to decrease with distance, and the exponential energy increase required to travel as such is not unreasonable)
Binary stars and other equilibrium comes to mind, but I conjecture that "free" time travel in perfect equilibrium would be impossible; your relationship with time can only be altered in respect to changes in the gravitational depth. However, they may have
So goes a theory
1. Build a time machine.
2. Go into the future to gather information about it.
3. Go back to your own time with your new knowledge.
4. ?????
5. Prophet!
Will work for bandwidth
Time travel isn't possible, except for the everyday kind that your wristwatch measures.
If time travel were possible, somebody (human, alien, whatever) from the future (perhaps billions of years into the future, or maybe just next week) would have traveled into the past already.
So, let's consider what can happen. Somebody will travel back in time to before the initial discovery in order to beat the ``original'' researcher to the punch. Now, we've got a cascade of ``inventions'' of the time machine racing backwards through time. Life and time-travel technology reach the earliest time after the Big Bang that the two are sustainable and both are prolifically spread throughout the infant universe. Clearly, that hasn't happened.
Don't think that some sort of morality would prevent this from happening, either. Time travel is an incredibly powerful weapon; consider what a knife to the throat of the infant Hitler would have done to history, and how many people would leap at the chance, consequences be damned. All it would take is one person to do so...at any time in the next many billion years.
The instant time travel becomes possible, the only possible method for self-preservation is to race to the beginning. After all, how do you know that some far-distant alien race with souls of pure evil won't do the same just out of spite?
There's a wonderful quote, and I wish I could remember who said it. ``Time is Nature's way of keeping everything from happening all at once.'' The obvious corollary is that, if you can break time, then everything will happen all at once.
Some people try to get around this in a few different ways. For one, there's the many-universes ilk: each act of time travel creates a whole new universe. In such a case, all of those universes would be on the same headlong rush to take time travel as early as possible. Besides, think of the incredible amount of energy and information needed to duplicate the universe--but I digress.
Others try to justify it by saying that it requires huge energy sources or otherwise make it hard. To this I say, ``so''? All you're talking about is a hard engineering project that'll take a lot of time. And--guess what? Even if it takes ten thousand years to build and the energy output of several stars, the payoff is worth it. Again, the alternative is to let somebody else do it...and invite certain disaster.
I take the mere fact that I'm typing this note as all the proof that I need that time travel is pure fantasy.
Cheers,
b&
All but God can prove this sentence true.
The best thing about having a working time machine would be pushing all who find this fascinating into it and sending them elsewhen.
If time proves to be a complex number, while I would find that fascinating I wouldn't tempted in the slightest to project the terms "backward" or "forward" into a polar coordinate system.
If there's any virtue at all to a discussion about time travel, it's that you can't determine whether mathematics or linguistics is taking the worst beating.
Your post intrigues me, but if you're really looking to prevent World War I, I can suggest people more culpable than Princip:
Grand Admiral Alfred Tirpitz: Led the drive to create the Imperial German High Seas Fleet, which aggravated tensions with the British Empire (the Naval Race and all that).
Colonel General Alfred von Schlieffen: Chief of the German General Staff before the war, architect of the Schlieffen Plan to attack France and defend against Russia, which included the violation of Belgium.
Bringing the British into the war was the real disaster. Had they stayed out, it is quite probable the France would have lost the Battle of the Marne and therefore the war. Germany would then have teamed up with Austria against Russia far earlier, and it is entirely conceivable that the war would have been over before the leaves fell, as the Kaiser had promised his troops.
A quick end to the war would have left the Central Powers dominant on the Continent, Russia in the throes of revolution (I imagine that defeat in the war would cause collapse), and France diplomatically isolated. Not a wonderful situation really, but nothing to lead to the Second World War.
Of course, the above is an exercise in what-if history, which generally gets dismissed as quackery...
~Chazzf
No statement is true, not even this one.
While real physics has always been about rigorous (and vigorous) lab work, the popular image of physics, and Science as a whole, has strayed from this considerably.
Gees. Not only do you insult theoretical physicists here but every other science that does not involve experimentation such as computer science and mathematics. Who are you to define what "real physics" and "real Science" is?
Witness, for example, the popular celebration of Einstein's thought experiments. The average layman is under the impression that Einstein reached his great intellectual climaxes by just sitting and thinking about things, maybe over a cup of hot chocolate. What people don't see is the hours of experimentation (real experimentation) as he tried to verify and correct the results of his thought experiments.
Einstein did some of his best work while employeed as a patent clerk [1] [2] [3]. As a patent clerk, he most likely did not have access to the laboratory equipment needed to perform experiments involving speeds close to that of light. In fact the first experimental verification of general relativity was done some years after his papers and by someone else.
So why is it like that? Are people just stupid?
Okay, you've called us all stupid. Now here's your chance to back up that claim by showing us proof of these supposed "hours of experimentation (real experimentation)" that Einstein needed to work out relativity.
Since the collapse of the Catholic Church in the times of Galileo Galilei, there has been a vacuum where religious fervor once stood. Science (or this fantastical mockery of Science) has filled that void, uncomfortably.
I don't know what country you live in, but here in the US, the Cathloic Church is a formidable force in people's lives and in public policies. It certainly has not collapsed.
Show the theorists some respect.
GMD
watch this
Your two objects have a velocity of 1/2 e only to the observer standing still at 0.0.0. Niether object has exceed the speed of light. At relatvisic speeds you can not simply add the velocity vectors to get the apparent speed. That is the whole point of relativity.
The Speed of light is NOT infinte. It is quite slow if one is trying to cross a galaxy. As you speed up you local times slows down. If you could reach the speed of light your clock would stop, and it would seem like you reach any destination in no time which implies an infinite speed. As far as we know, anything with mass cannot reach the speed of light (not by simply accelerating anyways).
So what has been proved? Clocks DO slow down when they travel fast. Light is bent by strong gravitational fields. In fact, everything we have the ability to currently test, predicted by the theory of relativity has check out so far.
Anarchists never rule
- It is (theoretically) impossible to accelerate to the speed of light, because it would require an infinite amount of energy to do so, so the best we can do is approach the speed of light.
- The closer you get to the speed of light, the harder it is to accelerate, because of said energy requirement.
Wouldn't time distortion then simply occur because things simply could not happen as fast? Your aging, your blood flow, the chemicals flowing between your synapses (this altering preception), the rate at which something burns, the rate electricity moves at, etc. all happen slower than they would if the object where traveling at a lesser speed, because the whole process takes more energy, correct?If this is true, what happens when an object comes to a complete halt in space, the absolute zero of velocity, if you will. Could that make a black hole or something?
IADNAP.
CAn'T CompreHend SARcaSm?
Here, since no one seems to be putting theories forward, here goes.
I think of time like a flashlight shining on a wall.
There is only one point shining at any one time. It may be possible to 'see' into the future, or travel there, but not backwards, namely because the Langoliers have eaten it.
It certainly is possible to travel faster than light, and will not result in time-travel. As time has shown again and again, there are no limits. Sound, Light, Warp 10, etc. So, this should tell you all one thing...
NEVER speak in infinitives. You will ALWAYS be proven wrong.
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