# Time travelling

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I've been thinking about how to do it and came up with these theories.

Travelling to the future or past using the closer to the speed of light you travel the slower time passes for you law of relativity.

I think you can travel into Earths future by getting in a space ship and travelling really fast for a few years. So what?? It'll be easier for us to perfect cryogenic suspension or whatever and travel into Earths future without even aging a day never mind a few years. So it's pretty pointless using high speed to travel into Earths future faster than you already are.

Travelling faster than the speed of light, why do people think once you pass the speed of light you're travelling backwards in time??

Consider this, you get a ship capable of lightspeed.

It travels 93 million miles in 8 minutes, you doulbe its speed and it takes it 4 minutes, double it again and it takes 2 minutes you keep doubling the speed and halfing the time needed to travell those 93 million miles. Until the doubling of speed only reduces the time needed from 0.00002 seconds to 0.000005 seconds. You will never get it to turn into -1 second or -8 minutes to travel 93 milllion miles.

What I can't visualise is if a ship flew across our heavens at the speed of light for 93 million miles and I was on it and it took me 8 minutes to make the journey. How would that affect time on Earth in relation to my own??

Travelling at lightspeed it would take me 8 minutes and the people left on Earth would see it for 8 minutes too.

Our sun is moving through our galaxy so when we look at the sun it is actually moved in relation to where it was 8 minutes ago which is what we see.

If I'm travelling 93 million miles at light speed and it takes me 8 minutes the people on Earth will still only see me 8 minutes away from where I started. Won't they??

I have a wild theory on travelling to the dawn of time though.

It depends on how the universe works though, some of which I don't know.

What do black holes eat? Is it energy, matter and space itself or just energy and matter??

Is the universe heading towards a super supermassive black hole??

There's a supermassive black hole at the centre of every galaxy, doesn't that mean all galaxies will eventually become just bigger supermassive black holes??

And if galaxies can collide can't they all collide and form one huge super supermassive black hole that can't contain all the matter/energy and blow it out in a big bang. An infinitely self replicating universe??

If black holes don't eat space itself, in other words you could have this SSBH but the space (universe less any matter/energy) around it still exists, couldn't you?

All you'd need to do then is live for a very VERY long time and hang around for the next universe to be created. Then you could go and visit the lifeforms that evolve in that universe.

I was oriiginally thinking you'd be able to visit Alexander the Great or someone but the universe wouldn't create itself in exactly the same way because your ship wouldn't be part of the matter spewing from the SSBH causing knock on effects that lead to the creation of Alexander the Great or even Earth for that matter.

But you could travel to the birth of the next universe and have a head start on any life that develloped in it.

I'm 50/50 on whether it's possible for us to be able to live that long, even through lengthening the human lifespan to 2 or 300 years, perfecting cloning and conscioussnes transference into the cloned body. But as life we could, our descendants would have to be the ones witnessing the new universe.

But they'd be able to do lots of crazy things like guiding a species towards living in peace and harmony by reenforcing their religious beliefs, appearing on top of a mountain and giving some guy some guidelines or transferring one of our peoples conscioussneses into one of their bodies and doing some unbelievable tricks.

Then once they reach that state of peace we can start introducing ourselves and teaching them what we know.

You could say that's what the aliens we're allegedly seeing right now are, then again they could have been born in this universe and just have developed before we have...

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People think that if you travel faster than the speed of light you could travel backwords in time, and if at light speed foward in time because of the special and general theories of relativity.

The faster you travel (acourding to special relativity) the more energy gained. The law $E=mc^2$, the more energy given, the more mass given as well. The universal speed limit - $1.86 \times 10^3$ mp/s - is the speed of light ($C$), the closer the speed of an object to $C$, the more massive the object becomes. Nothing can ever reach the speed of light (exept light an other EM waves/photons) because it will become so massive as it reaches $C$, that enough energy will not be available to keep the object going so it slows down.

The only way I can think of to reach the speed of light is to somehow power a space-ship on the energy collected from the high level of acceleration.

To travel faster than light, you'd have to gain so much energy that you slow down time enough to where even light is slowed down (only possible with a large amount of gravity), while you are contained in a sort of Time-Feild so you stay at a stable speed.

With that much energy the speed of time would now be in the negatives ($-n$), and time would be in reverse.

some of this I thought up on my own, but may have already been a published theory

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Ehhh, I'm not sure how accurate some of the above is, I know there are a few errors anyway.

" Nothing can ever reach the speed of light (exept light an other EM waves/photons) because it will become so massive as it reaches C, that enough energy will not be available to keep the object going so it slows down."

The object will not slow down, merely become harder to accelerate. The more energy you put in, the more mass is added. The more mass you have, the more energy is needed to accelerate the ship. To reach c would take an infinite amount of energy.

"The only way I can think of to reach the speed of light is to somehow power a space-ship on the energy collected from the high level of acceleration."

I'm not really sure what you mean by this, but you wouldn't be able to reach c by doing it.

"To travel faster than light, you'd have to gain so much energy that you slow down time enough to where even light is slowed down (only possible with a large amount of gravity), while you are contained in a sort of Time-Feild so you stay at a stable speed."

Time field? Light slowing down? Sounds like science fiction to me. I could be wrong, someone with more knowlede will have to comment on this.

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i see what nos is saying. dont know if you can have that sort of endless power though. thought you couldnt make more power than you use. good idea to play with though. i always thought

t=C+.000(repeating)1

thats why tacheons (if they exist) travel in negetive time. my spaceship idea was to have just one giant pulse of energy for an instant accel to the desired speed. but you would be a pile of mush.

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i see what nos is saying. dont know if you can have that sort of endless power though. thought you couldnt make more power than you use. good idea to play with though. i always thought

t=C+.000(repeating)1

thats why tacheons (if they exist) travel in negetive time. my spaceship idea was to have just one giant pulse of energy for an instant accel to the desired speed. but you would be a pile of mush.

Well thats fine, but you still wouldn't be able to reach c.

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" Nothing can ever reach the speed of light (exept light an other EM waves/photons) because it will become so massive as it reaches C' date=' that enough energy will not be available to keep the object going so it slows down."

The object will not slow down, merely become harder to accelerate. The more energy you put in, the more mass is added. The more mass you have, the more energy is needed to accelerate the ship. To reach c would take an infinite amount of energy.[/quote']

But the more mass added, would make it harder to accelerate, and therfore take more energy to keep at the same speed (much less actually accelerate), so eventually after loosing quite a bit of energy, the object won't have enough energy in it's body available, so it decelerates.

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']

"The only way I can think of to reach the speed of light is to somehow power a space-ship on the energy collected from the high level of acceleration."

I'm not really sure what you mean by this' date=' but you wouldn't be able to reach c by doing it.

[/quote']

What i mean by that, is if you use the energy that you collect from the high speeds (the energy that becomes mass) and use it to power the engine in your ship. all you need is a little boost to take of and then all the energy used as mass to slow you down is now used to power you the rest of the way. and on top of that, you don't really loose energy at all because you gain much more than you loose, and so you speed up.

To travel faster than light' date=' you'd have to gain so much energy that you slow down time enough to where even light is slowed down (only possible with a large amount of gravity), while you are contained in a sort of Time-Feild so you stay at a stable speed. [/quote']

light is the same speed realative to all observers (no matter what there speed), because it's the fastest thing in the universe. but what i described above is similar to what occors inside a black hole. with an infinite density the holes gravity is so strong that it's escape velocity it greater than C, so light is sucked in. and because the black holes gravity is so strong, time itself is streched and spegetified and messed up in all sorts of other ways that i can't think of at the moment. if time is messed up (and time is the cause of motion and energy and lots of other things), so if time is messed up, then motion and speeds are messed up, so many of the laws of physics and nature no longer aply, and that includes general relativity.

all the time feild part would be is when everything - except a small aura of time - is slowed down into the negatives in time's speed, while you (safe within the time feild) stay in the posotives.

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"But the more mass added, would make it harder to accelerate, and therfore take more energy to keep at the same speed (much less actually accelerate), so eventually after loosing quite a bit of energy, the object won't have enough energy in it's body available, so it decelerates."

This is incorrect. According to Newtons first law, an object will remain at a constant velocity until an outside force acts on it. You do not need to apply any force to have an object maintain its current velocity. It would only decelerate if an outside force was being exerted on it.

"What i mean by that, is if you use the energy that you collect from the high speeds (the energy that becomes mass) and use it to power the engine in your ship. all you need is a little boost to take of and then all the energy used as mass to slow you down is now used to power you the rest of the way. and on top of that, you don't really loose energy at all because you gain much more than you loose, and so you speed up."

This does not make sense. If this were to work, it would be a perpetual motion machine.

"all the time feild part would be is when everything - except a small aura of time - is slowed down into the negatives in time's speed, while you (safe within the time feild) stay in the posotives."

At the singularity of a black hole, relativity and all other known theories do indeed break down, and lose their ability to predict things. However this time field stuff, and "negative in time's speed" has no basis in any theories that I have ever heard. There are some good links on this site, look those up, and get a better understanding of just the very basics of relativity. I've never heard of any sort of negative time field, but I havn't heard of a lot of things. Basically I think its wrong because you are mistaken about numerous other things.

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The only way to travel in time is to instantaneously be at c. accelerating to c is what is impossible, but we can travel faster than it. acceleration is change in speed divided by time taken for the change to occur. If that time can be made 0, and our acceleration infinite, then we can reach these speeds. However, it seems to be our fate that anything we do has a duration, so this would be impossible in practice. Light travels at c, because the photons are created travelling at c. The proposed tachyon travels faster than c, becasue when it is created it is already faster than c. Putting the value for v > c for a tachyon into the equations for relativity gives a value for t < 0. (ie negative) This should mean that tachyons travel back in time as soon as they are created, which is possibly why we have never detected one. Perhaps the primitive humans of the past are being bombarded with tachyons created in our High Energy Particle Phsyics experiments? Who knows? Maybe if we could build a ship out of tachyons, with a recording device on it (also made from tachyons) we could use it to venture inot the past.

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what he said

and it may also be possible possible for a so called "hyperspace", which theoretically may be able to somehow change our dimension from 4-D to... say 3-D, where time wouldn't effect us (time is 4-D, and we'd be 3-D) unless were somehow effected by the vibrations of super strings in the 4th dimension.

but, if time dosn't effect us, then time can't keep us below C, and once we reach above C, then we can enter the 4-D universe at speeds greater than C. and if what Ben_Phys618 said is correct, then we would be (in a way) recreated when we reach a new dimension (and so if where recreated at greater than C, then we stay at greater than C).

and [tycho?], remember, a lot of these are theories of my own

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and could someone explain to me what tachyons are?

i understand what Ben_Phys618 is saying, but i don't know what tachyons are.

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i know we cant reach c. maybe the solution is finding a way around it. there are still alot of unknowns that can lead to these advances.

if our ancestors are being bomb barded with tachyons...if going above c you cant slow down to less c. so they wouldnt ever stop going through -n.

sorrry this is not well thought out post, taking the wife away for the weekend and she wont stop talking about dresses rotfl.

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what are tachyons?

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Theoretical particles with negative mass that exist only at speeds above the speed of light.

thanks

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Thanks for trying to keep everything close to the field of science (rather than speculation) [Tycho?] ,

basic facts of relativity, if you break these, make a new theory that doesn't include relativity:

1- Speed of light, c, is constant and unattainable by particles with mass

2- particles can't accelerate to c for the same reason particles at c can't decelerate to sub-c. Photons never slow down, even from a black hole, they get trapped, but their speed is constant, the wavelength changes.

3- The higher a fraction of c, the more inertial mass you have, the more inertial mass, the harder it is to accelerate, you reach infinite mass, unattainable speed limit.

The speed of light is constant because no matter how fast you move, you will always measure a photon's velocity to be c, reason being your measuring device is altered by the velocity your traveling relative to the photon, it combines very effectively to cause c to be constant.

time is relative, the faster you go, time remains constant to you, but to observers around you, you age slower, hence a photon never ages, its 'immortal'. If you were to take a spaceship and travel at a high fraction of c from and to earth, you would age a small amount of time, while millenia will have passed on earth.

noz92, no offence intended, but try to keep everything you say within the field of science by including links to where you get your theory's, and if its created by yourself, make sure to rid of as many holes in your theory by studying around the site and the web and (god forbid) school (though i've never found that to be a good place to learn these things ). But some of your ideas have roots in certain theories being created by physicists around the world so your not completely out of the blue, just keep looking around.

I'm still trying to make sure i understand what happens to an observer traveling at a fraction of c viewing the unaccelerating universe around him, and vice a versa for a relatively stationary observer viewing an accelerating observer (right now i'm thinking the accelerating observer appears to shorten/squish at higher speeds, akin to the term 'pancaking')

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noz92' date=' no offence intended, but try to keep everything you say within the field of science by including links to where you get your theory's, and if its created by yourself, make sure to rid of as many holes in your theory by studying around the site and the web and (god forbid) school (though i've never found that to be a good place to learn these things ). But some of your ideas have roots in certain theories being created by physicists around the world so your not completely out of the blue, just keep looking around.

[/quote']

what are the holes in my theory?

what would i search to try to fill them, i wouldn't know what to search on any search engine, what would i look for on this site, and 2 reasons i couldn't use school: 1) it's summer break, so i havn't even seen any of my teachers yet. and 2) i'm only 11 (an 11 year-old with a genius IQ, but still an 11 year-old).

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what are the holes in my theory?

what would i search to try to fill them' date=' i wouldn't know what to search on any search engine, what would i look for on this site, and 2 reasons i couldn't use school: 1) it's summer break, so i havn't even seen any of my teachers yet. and 2) i'm only 11 (an 11 year-old with a genius IQ, but still an 11 year-old).[/quote']

Please try not to be arrogant and defensive, I'm not trying to flame you or question your intelligence, I'm just giving you a few suggestions so that your later ideas and trains of thoughts will be more concise and intelligible.

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Any particle with on-zero real mass, in any given inertial frame must travel with a speed of less than c, it's a fundamental aspect of the Lorentz group.

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I'm still trying to make sure i understand what happens to an observer traveling at a fraction of c viewing the unaccelerating universe around him' date=' and vice a versa for a relatively stationary observer viewing an accelerating observer (right now i'm thinking the accelerating observer appears to shorten/squish at higher speeds, akin to the term 'pancaking')[/quote']

Hmm according too einstein the person watching the accelerating person will se him deformed in the direction he is accelerating.

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okay then, that makes sense.

One thing i want to understand:

A observer in motion at a fraction of c will witness the world around him age much faster than him.

An observer in motion at minute fractions of c will be witnessed to travel much faster than the 1st observer in the eyes of the 1st observer?

Observer 1 : Large fraction of c

Observer 2 : minute fraction of c

Obvr 1 travels so and so distance in so and so time witnessed by Obvr 1, he views Obvr 2 travel so and so distance much faster relative to Obvr 1 witnessing time according to Obvr 1.

does Obvr 2 witness Obvr 1 traveling at a large fraction of c or at minute speeds because his time rate of change (dt) is less than Obvr 2's dt?

I must be missing something.

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I remember hearing, once, that some scientists were already able to cause a particle to travel at the speed of light. Is this true or just a rumor?

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okay then' date=' that makes sense.

One thing i want to understand:

A observer in motion at a fraction of c will witness the world around him age much faster than him.

An observer in motion at minute fractions of c will be witnessed to travel much faster than the 1st observer in the eyes of the 1st observer?

Observer 1 : Large fraction of c

Observer 2 : minute fraction of c

Obvr 1 travels so and so distance in so and so time witnessed by Obvr 1, he views Obvr 2 travel so and so distance much faster relative to Obvr 1 witnessing time according to Obvr 1.

does Obvr 2 witness Obvr 1 traveling at a large fraction of c or at minute speeds because his time rate of change (dt) is less than Obvr 2's dt?

I must be missing something.[/quote']

There's no such thing as absolute speed (except for photons I suppose), velocity is relative, i.e. it can be defined with refernce to some other object.

Lets say that the first observer is travelling at a large fraction of c relative to the Earth/faraway stars/CMBR frame and the second observer is travelling at a small fraction of c relative to what we have defined as the 'staionary' frame (though I stress that it's completely arbiatry anyinertial frame in SR can equally be considered a stationary frame).

Assuming constant velocity the first observer does not see the world (i.e. objects in the staionary frame) age (i.e. clocks or other measurments of time as compared to the proper time in his frame) faster he sees it age slower, just as an obsrever in the stiaonry frame would see observer 1 age slower too.

Observer two observes observer one travelling at a large fraction of c still.

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I remember hearing, once, that some scientists were already able to cause a particle to travel at the speed of light. Is this true or just a rumor?

If the particle had mass, then it is a rumor indeed. If it didn't have mass, then it isn't much of a news story.

We have never been able to accelerate a particle to c. That would be in direct violation of general relativity, and would definately make news if it was correct.

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we can get particles pretty close, though. they go so fast, thier time slows and they last longer.

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