A real Time Machine.

[dguy6789]

OK lets discuss time travel, and the possibilites of time machines.


Speed+Time=The Speed of Light


No matter what the first 2 are, they MUST equal the speed of light. It has been proven that as something moves with greater velocity, the time relative to it slows down. So in theory, time would eventually have to be negative if the speed was great enough.

The speed of light is roughly 186,000 Miles per second.

As your speed increases, time slows down, correct?

Acording to this law, if you were at the speed of light,
time would = 0, as 186,000mps + 0 = 186,000mps(speed of light).

So if you could get to the speed of light, you could stop time.(relative to you at least)

But what if, you could go even further beyond that speed. Time would have to equal a negative number(going back in time) to equal the speed of light. Lets say 200,000mps+(-14,000)=186,000. You would be going back in time correct?

If this is possible, we would need an immense amount of power, and a way to keep a human being alive while going so fast, but if we passed these limitations, acording to the math above, is time travel possible?

 

[TuxDave]

Only if your initial formula was correct. Here... try this version instead.

TimeRate(to the traveller) = TimeRate(to the unmoving guy)*sqrt(1-speed^2/c^2)

Edit: Minor correction. So anyways, let's say TimeRate(to the unmoving guy) = 60 clicks/minute. As your speed approaches the speed of light (c), TimeRate(to the traveller) starts decreasing.

 

[dguy6789]

Dont know where i got that other formula. But googlin brought it upon me.

 

[TuxDave]

Originally posted by: dguy6789
Dont know where i got that other formula. But googlin brought it upon me.

Maybe it was just a simplified way to show the GENERAL idea that as you speed up, time slows down. Anyways, as far as I know, it requires an infinite amount of energy to accelerate to the speed of light and so us slowpokes are kinda stuck below it. I don't know what it says about things that already exist above the speed of light.

 

[eigen]

man that was one of the craziest OP's i have ever read.
Ausm

 

[kotss]

While the following might someday not be true, according to what I have read the speed of light in a vacuum is a universal constant. The reason photons can go the speed of light is due their very nature.
They only exist to mediate electromagnetic radiation and only exist at the velocity of light. They do not exist at rest and have no rest mass. They only have a mass due to mass energy equivalence. (E=mc²).
When an object other than a photon is accelerated it undergoes relativistic transformations with respect to
other obects relative to it. The properties that undergo transformation are length (distance), time and
momentum. For time and length the transformation diminishes the observed time and length for an observer who is not undergoing relativistic transformations themselves. For momentum you gain relative to an observer. Therefore at just a very tiny portion below the speed of light you have nearly an infinite momentum. In order to achieve the speed of light you would need an infinite force to accelerate the object to the speed of light. Since no infinite force exists, you will not reach the speed of light. The
3 forms of the Lorentz transformation are as follows:

Time - T(observer) = T(object) * sqrt(1 - (v²/c²))
Length - L(observer) = L(object) * sqrt(1 - (v²/c²))
Momentum - p(observer) = p(object) / sqrt(1 - (v²/c²))

Momentum - p = mv (mass * velocity)
Kinetic Energy - k = 1/2 * m * v²

As an object increases it velocity it gains an increase in kinetic energy and since energy is interchangeable
with mass the mass or total energy of the object increases.

An interesting fact appears for a photon if you apply the relativisitc transformations to a photon.
The photon is already travelling at c. So therefore the time and length a photon experiences is always zero. So a photon always travels 0 distance in 0 time. Obviously this is not practically true since even
light takes time to travel.

Remember to take into account the theorys of relativity.

Hopefully this explains why time travel by going faster than the speed of light is fundamentally flawed.

Almost forgot to mention: Even at small speeds we are undergoing relativistic transformations, they are just too small to observe. True relativistic effects do not start to manifest themselves until at least 10% of the speed of light.

Also for the person going relativistic speeds you do not observe any changes in your surroundiongs or in the passage of time. The reason is that all measuring devices that you are using are relative to you and
are therefore undergoing transformation just as you are and remain accurate for your frame of reference.

 

[Maverick2002]

is time travel possible?

Yes, though not in the way you're describing. Generally, the closer to the speed of light you go, the more time will elapse outside your frame of reference (hope I'm phrasing this correctly). The twin paradox explains this. You're also traveling through time every night when you look up at the stars. But in relation to your question, here are some of the obstacles that would have to be overcome:

At the speed of light:

-time stops
-your length contracts to nothing
-your resistance to acceleration becomes infinite (so you need infinite energy)

Good luck!

 

[cbehnken]

The speed of light may not be constant. They have observed that light traveling past Jupitor's speed is somewhat affected by gravity. Can't remember exactly where I read this...

 

[MobiusPizza]

Why don't people realise that time travel is just impossible?
Nature does not have a way of remembering their old self. You cannot ask the nature to go back and fetch what you did 3 days ago at 4:19 pm. This is the simpliest paradox to understand. All other paradoxes such as what happen if you go back and kill your mom/dad would you still exist. Nature must not allow any of this to happen because everything has to make sense. Any loops are not possible.

Assume you almost reach the speed of light, you feeled sloweed down in reference to people on earth, no matter how much you slow down more there's no way to even get time to stop. It's like one of the exponential decay curves you never reach 0.

 

[cbehnken]

Nothing is impossible. If the human race lives for an infinite amount of time then we will have an infinite number of discoveries.

People didn't think we could break the speed of sound or split an atom once.

 

[rgwalt]

Also, it *litterally* would take an infinite amount of energy to accelerate something with a nonzero rest mass to the speed of light. It is one of the consequences of relativity. We could not ever generate enough energy to go that fast.

R

 

[MobiusPizza]

There would always be something that is impossible. There are many examples of impossiblities in this world.

The fact that it takes infinite ammount of energy to reach speed of light is an example, which means reaching the speed of light is impossible by definition. It's like telling you to do a 1KM high jump which is impossible.

Impossible is impossible, nothing can change that.

 

[Zero Plasma]

It's thought not to be possible to go past the speed of light unless you always were and always will be moving faster then the speed of light.So as far as I know what you said is not possible for humans to do as we are moving less then the speed of light as of now.

Travel faster the the speed of light could be possible though, by way of wormholes and such.

 

[ApacheChief]

AnnihilatorX, how much you want to bet we could make some kind of prosthetic device to jump 1KM high?

You CANNOT say anything is impossible, because you don't know.

The universe doesn't keep a 'record' of itself, but it DID happen... time/space can be bent, it has been proven.

 

[Sahakiel]

Originally posted by: insolence
AnnihilatorX, how much you want to bet we could make some kind of prosthetic device to jump 1KM high?

You CANNOT say anything is impossible, because you don't know.

The universe doesn't keep a 'record' of itself, but it DID happen... time/space can be bent, it has been proven.

Why bother building a prosthetic leg? Distance is relative. Just go to some asteroid somewhere and jump off. Odds are, you'll get a lot farther than 1km.

As long as General Relativity holds, no human will travel back in time by exceeding the speed limit. You might as well try reversing the aging process by reversing the flow of entropy. Oh, wait...

 

[mcade]

An enjoyable book on the subject is Time: A Traveler's Guide. It is a fictional story with some very non-fictional science at the end of every chapter.

 

[Tab]

Could we potentally build something that went faster than the speed of light? I mean, lets say we had a spaceship with the best damn telescope on it and went faster than the speed of light, we could see back into our past.

 

[everman]

Originally posted by: cbehnken
The speed of light may not be constant. They have observed that light traveling past Jupitor's speed is somewhat affected by gravity. Can't remember exactly where I read this...

Well not exactly...This has to do with the mass of a very large object in space. Basically because of how big it is, it creates a larger curvature in spacetime, which makes for a longer distance to travel versus a perfectly flat surface. The speed of light never changes, merely the distance it has traveled which may give you the illusion that it slowed down.

 

[TuxDave]

Originally posted by: everman

Originally posted by: cbehnken
The speed of light may not be constant. They have observed that light traveling past Jupitor's speed is somewhat affected by gravity. Can't remember exactly where I read this...

Well not exactly...This has to do with the mass of a very large object in space. Basically because of how big it is, it creates a larger curvature in spacetime, which makes for a longer distance to travel versus a perfectly flat surface. The speed of light never changes, merely the distance it has traveled which may give you the illusion that it slowed down.

Well... I think the illusion that it has slowed down can only be seen if somehow you are separate from the space you're observing and can see the curvature of space. Since we're all stuck in the space that we're observing, even if light is moving through a very compressed area of space, it'll still look like it's going at the speed of light.

 

[MartyMcFly3]

Just put them in a Delorean

 

[wkwong]

objects that have been accelerated to the speed of light would have no mass, which means you would die once you reached that speed. but with quantum teleportation, would it be possible to reconstruct something in a state where they would be travelling at a speed faster than the speed of light? thus circumventing the need for an infinte energy source and the problem with travelling at the speed of light.

i'm not really sure how the teleportation thing works, so i'm really just throwing out an idea, lol.

 

[imported_Achilles]

Its already been done. Rent Superman 2 and see for yourself.

 

[DouglasAdams]

wasn't the earth flat not that long ago? wasn't it then "impossible" to travel around the world?
and wasn't the earth created at 9am on 4004-OCT-23 BCE?

surely all any1 can say is that given our current understanding, time travel would seem to be impossible

 

[IEC]

Err... no. I believe that this is like Calculus, where there is a limit that is being approached, that limit being 0. The faster you go, the slower time is relative to the rest of the world. So in other words, if you are going faster than the speed of light and traveled for a year, you might come back to Earth and find generation(s) had passed. Time shouldn't be able to be negative. The consequences of time travel would be DEVASTATING. Not to mention if you are going past the speed of light there is a theory you would become light yourself...

 

[Joerg]

Ok excuse me if im just being stupid here but it seems to me that people are making a mistake when they relate time tavel to the speed of light. The speed of light is in this case alot like the speed of sound. For example an asteroid hits and you see the explosion before you here it right?

Ok so now for the purpose of relating this to light lets just assume that sound never disipates. So now you could in theory sleep through the english lesson then travel faster than sound for the length of the lesson then stop and listen to it as the sound arrives at that point. Make sense?

Ok so now lets just speed it up 600,000x and call it light ofcourse the properties and everything are different and sound and light really have nothing to do with each other but for this purpose it works out fine. Anyways now lets say you build somethign that can travel faster than the speed of light and lets say signifigantly faster simply becuase we want to be able to do this and come back in time for lunch.

So your history project on ancient egypt is due. You jump in your faster than light craft and you shoot away from earth. Going at twice the speed of light you can see back one year for every one year of travel that means that to do this in one hour and go back 5000 years we need to be going somewhere around 87.6million times the speed of light to do this in one hours time. Ok so we have traveled our 5000 lightyears away from earth and we went alot faster than light so we arrive before the egyptians built the great pyrimids. Ok so the pyrimids are still built and we cant change that but we can see them being built only becuase the light or the image of them being built just now got to us.

I know really confusing but basically we only beat light not time itself. So in theory we could go back and watch something happen even a million years after it happened we just need to go faster than light and catch that image.

Ok so natures memories are stored as an image but the acctual matter would be there it would be a hallogram if you will. Sort of an empty image like peering into the the sky knowing that some of those stars are no longer there.

Ok now lets says that true time travel were possible by means of black holes or something my question is what happens when you create mass in that time frame you visit? One of the simplest laws in physics is that mass cannot be created or destroyed.

And again im only in highschool if my ideas are very flawed just tell me where im going wrong.