Is that possible for us to create space ship which could reach a speed of light?
349427
no, anything that travels close to the speed of light becomes more massive as it goes faster, and would actually become infinitely massive at the speed of light. this means it would take an increasing amount of energy just to get close, and an infinite amount to reach that speed. the only reason light can reach that speed is because it is made of photons which have no mass. even a tiny particle like an electron can never actually reach the speed of light.\n\nHowever, faster than light travel may be possible by warping space-time itself, using phenomena like wormholes or even black holes.
77099
it would be called superluminal.\n\nyou can read more about it here - \nhttp://en.wikipedia.org/wiki/Faster_than_light
3115
This is considered to be impossible.  As you APPROACH the speed of light, your energy and/or mass change.  If  you HIT the speed of light, your energy and mass approach zero and infinity.  So there would be nothing left of you to actually EXCEED the speed of light.\n\nBut I encourage you to try.  Write us and tell us how it goes!
596319
There is a big difference between predictions that the speed of sound could not be broken and that the speed of light cannot. It was always known that *some* things can go faster than sound. Bullets for example. The question was whether we would have the technology to get people to that speed.\n\nThe speed of light is very different since we haven't seen *anything* go faster than light in a vacuum. Nothing. Ever. Furthermore, the predictions of special relativity have been verified in particle accelerators when the particles are going to within a hundred thousandth of the speed of light.\n\nAs an example, at Fermilab protons are accelerated to energies of 2TeV. This is over 2000 times the rest mass of those protons. To accelerate something the mass of a *gram* to an equivalent speed would take about the energy of the largest hydrogen bomb ever exploded. This amount of energy would be needed for each gram to get to that speed, so multiply it by 75000 for a medium sized human. And that doesn't count the spaceship they would have to travel in!\n\nNow, this is how much energy is needed to get to speed we *know* about. To go faster would require even more. Unfortunately, we have never seen a wormhole of any type. But the predictions are that the energy requirements would be even more prohibitive than what I just described.
1085739
OK!! Ignore the people who are saying that nothing physical can travel at the speed of light.  Light is physical and does actually travel at the speed of light!!  \n\nOnto your hypothetical train.  If the train is travelling at the speed of light and you try to run from one end to the other, logic dictates that you'd be travelling faster than light, but this time logic fails us.\n\nIt is impossible, according to einstein to travel faster than light.  But, according to einstein, it is possible to run from one end of the train to the other!!  This is done because they would be in the same place!  This is due to a part of the Theory of relativity call Lorentz contraction! \n\nAccording to you, the train would be the same length as it would be if stationary, and you would feel like you were running as if it were stationary.  But relative to the observer that is 'stationary' (actualy no such thing according to einstein) you would be at both ends of the train at the same time because you and the train would be zero.  The formula for lorentz contraction is L=L(0) x (square root of(1-(v/c)^2)).  Where L is the length of the train according to an observer, L(0) is the length of the stationary train, v is the speed of the train, c is the speed of light.\n\nIf you make v=c then you'll see that the train and you have absolutely no length.
491273
Right now, we're not even close to faster-than-light (or FTL) travel.  All out traveling has to be done at less than the speed of light, so most stars are farther away than we can get to.  Even at half the speed of light (which is far faster than we can travel) it would take 8 years to reach the nearest star, not counting the Sun.  (Not to mention 8 more years to get home afterward!)  Nothing can move faster than the speed of light, so our best hope is to do just like they do on Star-Trek.  The found a way to bend spacetime to get to distant stars without actually moving through normal space, which had less of a curve.  Nobody has any idea how to do that now, so we just have to keep expanding our understanding of science until we do.  Until then, I think our best bet on meeting intelligent extraterrestrial life is to hope for them to come to us!
563154
There are things that can move faster than the speed of light, but they can't carry information faster than the speeed of light.  For example if you shine a spotlight on a distant mountain and then spin the light around so that the spot moves really fast you can easily get a situation where that spot of light goes faster than the speed of light.\n\nBut I think you were referring to particles that move faster than light maybe?  It was conjectured that a particle called a "tachyon" could go faster than light.  But these particles have never been detected, although serious efforts have been made to do so.  \n\nIn the real world if you keep adding energy to a particle, its speed will keep increasing, but it can never hit the speed of light.  Then again, maybe there can be some mechanism whereby matter could be made to "jump" to a speed higher than the speed of light without ever going *at* the speed of light?  I think nobody knows a way to do this, and it may also be impossible.  New physics would need to be discovered!
25993
No.  No terrestrial object can travel at the speed of light.  If you were traveling at the speed of light you would literally dissentigrate from the millions of pounds of air resistance pinning you down.
711259
I have always been a fan of this discussion. I propose that ANYTHING can travel faster than the speed of light (SOL). I also believe that was the driving force behind Einstein's assumptions. When we start talking about time slowing down as we approach SOL, we are talking about time RELATIVE to something else...If two people are together on a SOL spacecraft, then the time they experience is the same as if they were standing still. \n\nBefore I ramble on too much, What stops light from going any faster? If we had a theoretical spacecraft that could travel at 1/2 SOL, and we shot a laser off the front of it, how fast would the light be travelling? To the observers on the SOL-craft, the light would be travelling at absolute SOL, but to someone standing next to the craft when the laser was activated, would the light NOT be travelling at 1.5 SOL?
380796
simply no. it is not possible to have a perpetual motion machine because there will always be some energy lost. fusion is fantastically efficient in terms of mass to energy and has none of the radioactive problems of its fission counterpart. however it still uses up fuel and you cannot then reuse this. also the technology at the moment uses more energy than it produces meaning that this is still quite a long way off. this is perhaps the most realistic way of powering the spacecraft that you appear to visualise however there is still the problem that it cannot go fast enough and unless a way is found of bending space itself you cannot go faster than the speed of light or indeed reach the speed of light so the answer is no at the moment and no for the foreseeable future.
739346
yes it exists...\nbut cant be achieved by man....\nmay be in near future he may achieve tht too...i dont know coz now i cant travel into future..\nk...according to this guy called einstein..\nwhen some body travels at a speed relative to tht of light,lets say some 0.9c where c is speed of light then in tht frame the time contracts..he told a twin paradox to make it clear..\nlets say there r 2 twins of age 25...if one of them travels at a speed of some 0.9c for some 20 yrs (this 20 yrs is in our frame)\nthen after tht when he comes again to rest then he finds himself to be some 27 yrs old when his brother is 45 yrs old..\nso its equivalent to going into future...\nbut till now there is no theory to prove that travelling into past is possible..\ni think thts not possible...coz past is already happened n if its possible we can change the past....which is not possible as it is already happened....\nits all just theory...i wonder how can anyone achieve a speed relative to that of light....can any material sustain that much of speed???no way...so i think we cant make such time machine which can travel at a speed relative to that of light...
34913
It is not possible for any particle that has mass to travel faster than the speed of light. The reason has a lot to do with relativity. Because the faster you go, the slower time passes for you. So if you are at 80% of the speed of light, and launch a projectile in front of you at light speed, because of your slow passage through time, it will still appear to you to travel at light. Everything is relative, and because of that, certain constants like the speed of light never change.\n\nAlso, a particle with mass would achieve infinite weight at light speed. Since you can't obviously exceed infinite weight, you can't exceed light.\n\nThe ideas behind things like "warp speed" don't propose actually traveling faster than light. What they propose is taking shortcuts through space, kind of like skipping a stone across the surface of the water. Even "warp speed" is subject to the laws of relativity.
672393
Right now, many scientists believe that we cannot go faster than the speed of light.  As you get closer, the plane would get heavier and heavier until it slowed down.  Right near the speed of light, the plane would weigh almost infinity so it wouldn't be able to go faster.\n\nIt might be possible to somehow bypass it, but that's mostly science fiction right now.
265284
You can't reach the speed of light in any conventional way, but you can get as close as you want, provided you can keep applying acceleration.  \n\nThe best way to do a thought experiment of time dilation for special relativity (special relativity being the case in which you consider high velocities, general relativity just applies this same model to all spacetime trajectories with the observation that gravity is indistinguishable form a physical acceleration) is to consider the case of a "light clock".  \n\nFor a light clock, you have a laser pulse generator, a mirror at some distance, and a pulse counter next to the laser.  Everytime a pulse is recieved at the counter, another pulse is sent from the laser, and so you have a clock that "ticks" at a rate determined by twice the distance from the laser to the mirror.  So, what happens when you move this clock?  If the clock is arranged such that the pulse bounces back and forth perpendicular to the direction of travel, it's easier to get the basic idea.  \n\nThe speed of light is always constant, but as the clock moves at higher and higher speeds, from the perspective of a stationary observer the total distance traveled by the light increases, since now it's going diagonal.   But, to a person traveling along with the clock, it doesn't appear to travel any greater distance.  \n\nIt's something like a person standing in a train car or bus tossing a ball up and down.  While the ball is up in the air, it travels horizontally by the distance the bus has moved while it's been up in the air, so the total distance traveled by the ball is much longer if the bus is moving rapidly instead of stationary.  For normal speeds, the Gallilean transforms are sufficiently accurate, so a stationary observer and the person tossing the ball can agree how fast it's moving in each axis, and how far it moves, just by adding the horizontal velocity of the bus to the vertical velocity the ball is tossed with, and come up with the same wider parabola for higher speeds and narrow parabola for low speeds, or stationary cases.  \n\nBut, light has an interesting property...  it must remain at the same velocity for all observers no matter what their speed relative to the light.  So, in the case of a ball, we can simply say that it's moving faster than it looks to the person on the bus with it, because there's the added background horizontal velocity.  If you add the vertical and horizontal velocity vectors, the sum is longer than just the vertical velocity.  \n\nBut, in truth, how can you know if you're moving at a constant velocity?  There are no pseudoforces of acceleration if you're moving at a constant velocity, but if light behaved oddly by traveling faster in one direction that the other, you would be able to tell if there was a fixed frame of reference outside of your motion, and this would allow you to determine a fixed location relative to the universe as a whole, and even determine where the center of the universe is.  But it doesn't have a center, or all points are equally the center, depending on how you want to look at it, so there can't be any way to tell if you're moving at a constant velocity, and so light must travel at the same speed in any direction when viewed by any set of observers, no matter what their relative velocities are.    Not surprisingly, we find this also comes out from Maxwell's equations describing the propagation of light, the velocity winds up being proportional to one over the square root of the product of the electrostatic permittivity and the magnetic permeability of empty space, a number which is absolute and gives no preference for directions or relative motions.  This isn't surprising since, like I said, it's a necessary condition for a centerless universe.    \n\nSo, the speed of light must remain absolute, but something has to give.  Since the light clock is ticking slower becaus
958904
Building an engine that can get close to the speed of light is much easier, we basically know how to do it now, a low thruse engine that can run for long periods of time in space will just keep accelerating since there is no resistance. NASA is now developing such engines - ion engines.\n\nConversly we don't really have any good ideas on how to build an engine to bend space, or if it is even possible.
1127724
As you approach the speed of light your relativic mass approaches infinity (according to einstein's theory e=mc^2) and your acceleration approaches 0.  since your mass would be infinite it would require an infinite amount of energy.  We have no way of obtaining an infinite amount of energy and since  nothing but light can go the speed of light, nothing can go faster.  (you have to go the speed of light first in order to go faster than it)
55482
It would take too much energy to accelerate anything physical anywhere close to the speed of light. The amount of energy required increases asymptotically to infinity as one approaches the speed of light. However, canukinsocal made some interesting speculations. It is possible that we might eventually be able to send digital avatars of ourselves, connected into our nervous systems. Using something like this, we might be able to experience transmission of an extension of our senses and possibly consciousness at the speed of light.\n\nWhether this will happen in our lifetimes is an open question, but it is interesting to contemplate.