The Theory Of Relativity What does it mean for space travel?

[mitchellmckain 0]

So how is it possible that you can go somewhere as fast as you want even though you never exceed the speed of light? The answer is lorentz contraction. This means that all lengths and distances in the direction of relative motion are decreased by the factor gamma. In fact gamma is known as the lorentz contraction factor.At 99.5% of the speed of light you would see the earth moving away from you at 99.5% of the speed of light and your destination coming toward you at 99.5% of the speed of light, just as the people on earth see you moving away from them at 99.5% of the speed of light. But since gamma = 10, for you the distance between earth and your destination is only one tenth the distance as seen by the people on earth. So it only takes you 4 tenths of a year to get to the nearest star while it takes 4 whole years for the people on earth to watch you go to the nearest star.One way of looking at this is to say that time on your ship is passing only one tenth as fast as time on the earth.

[jet 0]

jet, what you dont seem to understand, is that mass and energy are the same thing.

the fasdter you go, the more energy you have, and therefore the more mass you have.

the more mass you have, the more energy is required to accelerate you.

 

mass increaces exponentially.

 

at the speed of light, you have infinite mass.

and an infinite amount of energy is required to accelereate an ininite mass.

 

its got nothing to do with friction.

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mass and energy are not the same thing. If they were, why would they be on two different axes of the same graph? At the moment, physics does indeed dictate that light is the fastest travelling thing ever. If it were not, the entire area of physics and relative science would be rewritten. But it has been before. Remember the times when people thought everything revolved around earth, or even that earth was flat?

 

Another thing that hasn't been taken into account is other dimensions. The fourth dimension is often thought to be that of time.

[amrit_i 0]

yes, if we keep relativity in mind then we cannot travel faster than light as Einstein declared, but his own later investigations into quantum physics and seperate works by various minds reveals that when dealing with the bizzare laws of quantum physics, relativity and the speed of light as a limit break downrelativity says that nothing can travel faster than light, not even information. Thus when a hydrogen atom goes bust (hypothetically) in andromeda there is no chance that this event would happen somewhere else in the universe simultaneously as the information would travel maximum at the speed of light.......however we see through repeated experiments in quantum physics that this does in deed happen sumtimes and information can travel faster than light, instantaneously in fact.this has some startling implications on matter and mind as we understand it. quantum laws are now making it increasingly clear that the human mental consciousness directly interacts with the matter around it......ancient Chinese and Indian texts claim that the mind and matter are both two forms of the same one energy, something that quantum physics is starting to believe.the way i understand all this then is such: - due to relativity, we cannot ever travel faster than light, because we have a mass and as such our mass would need to be pushed infinitely to travel faster than light.....but the very components of light, photons, are massless!!!thus we can travel to the stars provided we are massless, how do we do that? we use our mind. i do not mean imagination but that if we can understand the interactive relationship of mind and matter, we might go to any end of the cosmos using our mind as the propulsion drive, as the hyperdrive or as the improbability drive

[Moody 0]

The problem with going at the speed of light, is that you can't. As dear mr Einstein said, anything that moves, is slowing down. And it gets smaller. A spaceship that accelerates, shrinks and deaccelerates. When it would reach the speed of light time would stop and the spaceship would disappear. That's why the speeds of light is the limit.Quantum physics is about small things, about electrones and quarks. If we would be massless, we could travel faster than light. But the problem is, if we are massless, we can't travle in the first place. I'm curious when somebody proves Einstein wrong, but I don't think I'll live to see that scientist.

[mitchellmckain 0]

The problem with going at the speed of light, is that you can't. As dear mr Einstein said, anything that moves, is slowing down. And it gets smaller. A spaceship that accelerates, shrinks and deaccelerates. When it would reach the speed of light time would stop and the spaceship would disappear. That's why the speeds of light is the limit.

 

I'm curious when somebody proves Einstein wrong, but I don't think I'll live to see that scientist.

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No one suggested going at the speed of light. The question again is what is the limitation that relativity imposes upon space travel. How soon can you get to a star 10 light years away?

 

It is a myth that scientist are eventually proven wrong by later scientists. If that were true why do we still teach Newton's physics in school. It was never proved wrong. It was merely improved upon. I think the same is the case with Relativity. It will never be proven wrong. Something that works so well for so long doesn't get disproved.

[finaldesign1405241487 0]

Everyone is going Star Wars crazy and no one is here to give a stand and say something like: "Star Wars is a movie - an imagined fantasy that most probably cannot be real in our life. So ditch the imagnination and go on with your life!"

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Ok, first of all, you are thinking way off now... People watch the movies for about what 55-65 years now... That's not a loong time, but did you know that when first car is invented, car's speed was aprox. 25 km/h and people think that if car could go 100 km/h human body in car will be destroyed by it's speed. (!) Now, same thing with airplanes, breaking the speed of sound, diving into deep sea, jumping with parachute, landing on Moon!!!

Now people are crazy and they like to think something is impossible just because they are scared of unknown... What people think now about man landing on Mars? Mostly people think it's pretty impossible, because the lack of technology. But the aren't aware about how fast technology advances forward.

You look at STAR TREK episode now, and you may say: "Blah! That warp speed is imposible" But hey! What the people tought about some of the greatest philosophers in the world? That they probably crazy. And many of them was actually crazy. Why? Because they where crazy enough to think and invent stuff that noone else would dare to do.

 

So, don't make harsch decisions yet. Many, really many things still wait to be discovered by human race.

[mitchellmckain 0]

One of my points in starting this forum is because I peceive that a lot of the resistance to relativity was due to a lack of understanding of it. People dont understand that relativity is not an obstical to star travel. Just because we cannot go faster than the speed of light does not mean that we cannot go to the stars as quickly as we want. According to relativity we can cross the galaxy in seconds. It is just that we cannot expect to make it home for dinner afterwards.

yes, if we keep relativity in mind then we cannot travel faster than light as Einstein declared, but his own later investigations into quantum physics and seperate works by various minds reveals that when dealing with the bizzare laws of quantum physics, relativity and the speed of light as a limit break down

This is inaccurate. What breaks down is local realism. This is really a comination of things like the speed of light and determinism. But the weak link here is determinism not the speed of light. Some people cling stubbornly enough to determinism for philosophical reasons that they would rather toss the limit to the speed of light. But all of scientific evidence and logical consistency suggest it is determism that does not hold, and that the speed of light is unbreakable. Scientist now discard all unified field theories which have tachions (which go faster than light) as evidence that these theories are wrong.

however we see through repeated experiments in quantum physics that this does in deed happen sumtimes and information can travel faster than light, instantaneously in fact.

This is simple untrue. Bell's experiments does show that there is a connectedness to the universe which exceeds the speed of light but it connot be used to transmit information. There is no way to send a message faster than the speed of light.

quantum laws are now making it increasingly clear that the human mental consciousness directly interacts with the matter around it......ancient Chinese and Indian texts claim that the mind and matter are both two forms of the same one energy, something that quantum physics is starting to believe.

As much as some people would like this to be true. It is not. This is a misuse of the results of quantum mechanics. It absurd to think that consciousness is the determining factor in quantum mechanics that leads the existence of cats which are both dead and alive at the same time. However, with the downfall of determinism, of which quantum mechanics is definite evidence, science can no longer be used as a blunt club to disprove or scoff at the belief in that mental consciousness interacts directly with matter.

the way i understand all this then is such: -  due to relativity, we cannot ever travel faster than light, because we have a mass and as such our mass would need to be pushed infinitely to travel faster than light.....but the very components of light, photons, are massless!!!

thus we can travel to the stars provided we are massless,

I am afraid not. Massless objects travel at the speed of light. Nothing can go faster that the speed of light because it is really an infinite speed. To go faster than the speed of light is logically equivalent to traveling backwards in time.

how do we do that? we use our mind. 

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I have no objection to this. I believe there are such things as esp and such. I also believe that there very nature will always make them somewhat unreliable. We may one day be able to travel to distant galaxies with esp or something but I think that we will never be able to prove that we have done so.

[MajesticTreeFrog 0]

No one suggested going at the speed of light.  The question again is what is the limitation that relativity imposes upon space travel.  How soon can you get to a star 10 light years away?

 

It is a myth that scientist are eventually proven wrong by later scientists.  If that were true why do we still teach Newton's physics in school. It was never proved wrong. It was merely improved upon.  I think the same is the case with Relativity.  It will never be proven wrong. Something that works so well for so long doesn't get disproved.

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As for the question about space travel, going to a star 10 light years away will take AT MINIMUM 10 years. However, to those ON the spaceship on that voyage (assuming the ship moves at lightspeed), the travel will seem instantaneous.

 

There are, however, proposed solutions for the problem of getting somewhere faster than light. Basically, they all involve freaky hax of the universe. For instance, it only takes that long to get there if you travel through the intevening space. If we can (through worm hole or other method) find a way to ignore intevening space, then we get there faster.

 

One proposed method involves quantum entanglement of large numbers of particles creating a FTL teleporter.

 

However, these methods are generally a long long long way off, and maynot even work. So, interstellar travel a la startrek may not be possible.

[mitchellmckain 0]

As for the question about space travel, going to a star 10 light years away will take AT MINIMUM 10 years.  However, to those ON the spaceship on that voyage (assuming the ship moves at lightspeed), the travel will seem instantaneous.

Yes that is right, accept that you should say near lightspeed, say 99.9999995% of light speed, which is close enough to make a 10 light year voyage last only a third of a day. So why not accept this fact and envision the future of space travel that this implies rather than making up ridiculous fantasies about space empires and such. Like maybe we don't need government in space. Let there be exploration and settlement and leave each other alone, which sounds good to me. What is it that people find so hard to let go of?

There are, however, proposed solutions for the problem of getting somewhere faster than light.  Basically, they all involve freaky hax of the universe.  For instance, it only takes that long to get there if you travel through the intevening space.  If we can (through worm hole or other method) find a way to ignore intevening space, then we get there faster. 

Yes and Star Trek had these transporters that take apart your atoms and reassemble them at your destination. All these ideas sound like fun science fiction, but there is no science or technology to make us think that any such thing will ever exist. In fact, relativity tells us that if such means did exist for large distances we would have the same kind of paradoxes that we have in time travel (You know killing your mother before you were born). So all these fantasies still require that relativity be wrong somehow.

One proposed method involves quantum entanglement of large numbers of particles creating a FTL teleporter. 

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There is not even a good idea in this one, just technobabble to impress those who know a little about quantum physics, but not enough.

[Mahanon 0]

We all kinda of know what the Theory of Relativity means for space travel.... but for instance what if it was wrong has anyone even stoped to consider that.I'm not saying it is wrong but everything we knew of formed from that theory would be wrong also wouldn't it guess we won't know until we get out there and start exploring.

[DigitalDingo 0]

We all kinda of know what the Theory of Relativity means for space travel.... but for instance what if it was wrong has anyone even stoped to consider that.
I'm not saying it is wrong but everything we knew of formed from that theory would be wrong also wouldn't it guess we won't know until we get out there and start exploring.

Actually everything the theory of relativity has said has been proven correct through experiments â except one! And I canât remember what it isâŚ
As far as I remember it has something to do with gravity waves going through space. Can anyone correct me here?

But it is very clear that the theory of relativity sets some limits for our further space exploration. But it actually also says another quite interesting thing: the faster you go, the slower time will go. This means that if you travel with the speed of light the time will stop!
I know this is impossible, but think about it: if we could fly at the speed of light then we would not get any older â no matter how long time we will fly at that speed.
If we could get near the speed of light we actually wouldnât age very quickly. It would then be possible for one generation of humans to cover enormous distances in space. But of course we would need some source of energy to make us fly this fast.

Here one particle gets very interesting: the tachyon. Tachyons are so far only a theory, but many things indicate that these particles really exist.
Tachyons are very strange because of their mass: the mass squared is less than zero! (m^2 < 0).
Now people with a little understanding of mathematics would say this is impossible, and yes, it seems so. Thatâs why these particles are only a theory.
Now the interesting part of these particles is that they can travel faster than light. If they were found to be real they could probably help us, not to travel at the speed of light, but a lot faster than today.

But it is certainly a problem, that if you could travel faster than light you could go back in time. This is also a part of the theory of relativity, and it will make it quite difficult to observe and understand these tachyons.

And finally just a little funny poem I found:

There was a young lady named Bright,Whose speed was far faster than light.
She went out one day,
In a relative way,
And returned the previous night!

    -Reginald Buller

[MajesticTreeFrog 0]

As I see it, long distance travel will only happen one of a few ways:The first is teleportation using quantum entanglement.The second is coldsleep-research here is very positive. Travel doesn't happen fast, but it does happen.The third is any of the space bending ideas: worm holes, jump gates, space fold generators. Frankly, I think the first is the most likely method to be eventually used, as it is the only one we know that might work and is also fast.

[mitchellmckain 0]

As I see it, long distance travel will only happen one of a few ways:

 

The first is teleportation using quantum entanglement.

 

The second is coldsleep-research here is very positive.  Travel doesn't happen fast, but it does happen.

 

The third is any of the space bending ideas: worm holes, jump gates, space fold generators.

Frankly, I think the first is the most likely method to be eventually used, as it is the only one we know that might work and is also fast.

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But why do you say this? You demonstrates that people put more faith in science fiction than science. And the reason is probably only that they understand it better. A sci fi book that accepts the reality of relativity at least as far as travel is concerned is "Speaker for the Dead" by Orson Scott Card. Go one step further and give up on the idea of instantaneous communication and space empires and other such nonsense and then we can try to imagine the future as it might be. Ok so ftl travel would be nice, but so would magic spells to turn garbage into food. Makes more sense to focus on what is possible, don't you think?

[mitchellmckain 0]

But it is very clear that the theory of relativity sets some limits for our further space exploration. But it actually also says another quite interesting thing: the faster you go, the slower time will go. This means that if you travel with the speed of light the time will stop!I know this is impossible, but think about it: if we could fly at the speed of light then we would not get any older â no matter how long time we will fly at that speed.
If we could get near the speed of light we actually wouldnât age very quickly. It would then be possible for one generation of humans to cover enormous distances in space. But of course we would need some source of energy to make us fly this fast.

We would not get older because it does not take that long. Relativity affects time and space not the aging process. The point is that relativity does not limit further space exploration! We can get anywhere as fast as we would like. What it does interfere with is our ability to make space empires which just makes for fun stories like star trek.

Here one particle gets very interesting: the tachyon. Tachyons are so far only a theory, but many things indicate that these particles really exist. Tachyons are very strange because of their mass: the mass squared is less than zero! (m^2 < 0).
Now people with a little understanding of mathematics would say this is impossible, and yes, it seems so. Thatâs why these particles are only a theory.
Now the interesting part of these particles is that they can travel faster than light. If they were found to be real they could probably help us, not to travel at the speed of light, but a lot faster than today.

Tachyons are not a theoretical particle proposed by today's physics. They are predicted by theories which are considered flawed and incomplete because of this prediction. None of today's scientists believe that tachyons really could exist. It is just an idea that sci fi shows like star trek could use to entertain you with its techno babble.

But it is certainly a problem, that if you could travel faster than light you could go back in time.

That is correct, which is why none of today's scientists believe that ftl travel could ever be possible. Going back in time makes fun stories but it is a logical contradiction.

[DigitalDingo 0]

We would not get older because it does not take that long.  Relativity affects time and space not the aging process.  The point is that relativity does not limit further space exploration!  We can get anywhere as fast as we would like.  What it does interfere with is our ability to make space empires which just makes for fun stories like star trek.

You're right, I should have thought of that with the aging...
But I still don't agree with you saying "We can get anywhere as fast as we would like." The theory of relativity forbids that - which you fully agree with later...

Tachyons are not a theoretical particle proposed by today's physics.  They are predicted by theories which are considered flawed and incomplete because of this prediction.  None of today's scientists believe that tachyons really could exist.  It is just an idea that sci fi shows like star trek could use to entertain you with its techno babble.That is correct, which is why none of today's scientists believe that ftl travel could ever be possible.  Going back in time makes fun stories but it is a logical contradiction.

Are you sure of this? I could have sworn that many scientists saw the tachyons as a possible solution to many observations, including the accelerating expansion of our universe.
But nevertheless in 1973 Philip Crough and Roger Clay fell over an interesting observation using a large particle detector. They saw what some expects to be a superluminal particle (a particle that travels faster than light).
This result has never been reproduced so we canât make any conclusions upon that. My intension was only to show, that some people still believe in these particles.

Can I hear somebody say: â1973? Thatâs a ****ing long time ago!â?
It is. But as recently as in 1996 the scientist Erasmo Recami came with the conclusion, that it actually is possible for tachyons to have real mass.

So I still believe scientists are taking this particle seriously.