can we achieve light speed?
410964
i think its very much possible to travel at the speed of light, its just that we would need an extremely strong processor (like a fax machine) to break down the matter that we are made of into energy (E=MC^2) and then after reaching the destination just convert the energy back into matter. (not possible with the technology we have today)
214684
No massive object can move at the speed of light, so the question is ill-posed. Sorry.\n\nAs a physicist, please let me give you a little advice: don't loose your time with this nonsense, try instead to focus on the mathematics of the relativity theory, that's the way to understand it. The rest is pseudo-science.
364291
No, because according to Einstein's equations, to accelerate anything towards the speed of light would require more energy than exists in the universe (after converting all matter to energy).\n\nThere is a theoretical particle that never goes slower than the speed of light, but it has not been experimentally proven. They're called tachyons. http://en.wikipedia.org/wiki/Faster-than-light
376581
Theoretically it is possible to build a spacecraft with that speed. Nasa came to me with that proposal. I gave them a design and asked them to design an engine that would generate INFINITE amount of energy. They are working on that.[you see an object offer more and more energy as it nears speed of light till at c it needs infinite e. Sure a body can theoretically have speed GREATER than light.
366136
Not really - As it would travel at the speed of light (or the lack of) - but there would be a delay of a few picoseconds.....
204272
Light travels faster than sound.
1186042
That's the problem. You can't go beyond the speed of light. It is the cosmic speed limit. But if you could, then you'll be able to travel through time, past and future.
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.
51835
The physics community thinks not, but that never proved anything. The assumption is that nothing can travel faster than light. The answers are usually along the lines of, "since quantum entanglement happens instantaneously, its faster than light, but nothing can travel faster than light, so its impossible".\n\nThere may come a future theoretical structure in which lightspeed is surpassed under some circumstances, without temporal repercussions, then this assumption does not hold.\n\nI would add that I think its possible, based on an experiment described in Brian Greenes fabric of the universe that he uses to explain that its not.\n\nIts a simple extension of the two slit experiment where, immediately after the slits you use a photon doubler to create two entangled photons for each one passing through the slits. One for each slit. One photon carries on, the other is bent off at 90 degrees using a half silvered mirror and sent a long distance.\n\nIf no measurement is made on this second photon,, the other photons act as waves and you get an interference pattern. If a measurement is made, they act as particles and you get hotspots behind each slit.\n\nMy extension is that, by choosing to measure the photons that travel a long distance, you can instantaneous make the photons produce an interference pattern or not. Such a pattern would be noticable. If the split photons have travelled many light years, this pattern should be formable in a few seconds, so the message is coded in interference / non interference. Much like morse code in dots and dashes.
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.
509153
nice question!\nhowever to me the answer would be that it would never be possible\nu should be knowing the relation b/w mass and velocity as \nnet mass= actual mass/[square root of 1-v/c(squared)]\nhere only v/c is squared\nso u see, as the velocity increases the mass of the body increases and hence this compells the body to slow down as mass is inversely proportional to velocity(since constant thrust is applied)\nhence it would never be possible to attain the speed of light, as by this hypothesis at the velocity of light, the mass of the body becomes infinite
1061558
Moving faster than light isn't really the real issue for space travel as traveling AT the speed of light solves all the distance problems(unless you are interested in time travel!). Of course that in itself is a big challenge. If one could demass the vehicle then surely one could achieve the speed of light!!! Afterall photons do travel at this speed.\nBut we would do very well even with speeds like .99999c because time dilation will reduce the time required drastically. Have the science, just need the technology!
109643
No you can not.\nNothing can travel faster than light. Not even light itself.\n\nIf you think that light is a wave (like a wave on the ocean) Imagine that you were riding one wave and were trying to make a new wave from your position (with equal frequenzy ofcours). The new wave would not have twize the speed as the one you were riding, it would have the same speed as the one you ride (try in the bathroom and you will see).\n\nMy point with this explanation is that the light from the back of your car will never reatch the mirror. I think your mirror would seem black, because no light would reatch it. The lightwave from the back of your car would be "flying" towards the mirror in the same speed that the mirror would fly from it. :)
970195
This is one of the oldest questions in the world, after Einstein came out with his special relativity.  The answer is that no matter how fast you are going, your headlight beam is STILL shining ahead at the speed of light. This is exactly what the equations say, and it works.  If it wasn't true, then all the giant particle smashers in the world costing billions of dollars wouldn't even work.
916821
Yes the headlights will work!!  Einstein's theory of special relativity explains that space and time "dilate" as the observer approaches the speed of light so that the observer will ALWAYS be able to "measure" the speed of light to be 300 million meters per second no matter how fast he is traveling.
689820
Neither you, nor the train, could ever travel at the speed of light since both of you have some non-zero rest mass.\nIn order to accelerate something with a non-Zero rest mass, an infinite amount of energy would be required....and in the whole universe, there is not an infinite amount of energy.\n\nBut lets say you were traveling just under the speed of light...at 99.99999999999999% of c and you began to run toward the front of the train, \nyou would still NOT be traveling at or above the speed of light (as seen from an outside, "stationary" observer) since at relativistic speeds such as this, velocities do not add in the normal Galilean way, you would still be traveling slower than the speed of light.
37094
well, its absolutely impossible to travel at the speed of light, but lets pretend you can so i can actually give you an answer to the question. The speed of light is actually the ultimate speed limit to the universe, nothing can travel faster than light, so although you would expect the light to be going at twice the speed of light (you plus the speed of light, because of einsteins theory of relativity)it can't because it is physically impossible for even light to travel faster than the speed of light so it would be going at the same speed of you and not reach any path in front of you. Of course, if you turned on your headlights before you started moving, the light would always be one step ahead of you.\n\nbut again, this situation couldn't happen anyway since you can't get to the speed of light, it would make the denomonator in the lorentz factor 0, and you cant have a 0 in the denomonator of a fraction.