can we travel at the speed of light?
399905
We've actually run experiments that EXCEEDED the speed of light - which means the observer detected a particle before it left the emitter.  Wish I still had the link to give you.\n\nWeird science.  But real.
351358
The first answerer is right about the mass increase.  As a mass approaches the speed of light, one of the effects is that the more energy you provide it in order to increase its velocity, the more the mass increases, according to Einstein's famous formula E=mc^2.\n\nThe speed of light is the absolute limit for velocity.  A mass can approach closer and closer to this speed, but can never surpass it.  So, to answer your question, mankind can and likely will build spaceships which can go significantly faster than the present-day ones can, but we will never be able to travel at the speed of light.
117448
From our current undestanding of physics, we cannot. That does not mean in 500 more years or 5000 more years we will not have a better understanding of physics that includes methods for travelling faster than the speed of light in a vaccuum. However, at the moment it looks very doubtful. \n\nWe have substantial evidence that special relativity is true from years of operating particle accelerators. From special relativity, it appears that it would require an infinite amount of energy to accelerate to the speed of light. The glib manner people here are discussing an infinite amount of energy tells me that people do not understand what infinite means. \n\nAn infinite amount of energy is more energy than the sun produces. It is more than the energy produced by a billion suns. It is more than the energy produced by a billion galaxies full of hundreds of billions of stars. It is more energy than would be produced if every particle in the universe (about 10^70, the Eddington Number) was converted into a star like our sun. In fact, it is an INFINITELY greater amount of energy than 10^70 suns would produce. \n\nIf something is going at a speed greater than the speed of light in a vacuum (tachyonic speeds), then presumably the formulae we have for special relativity would not apply. There has been some occasional attempts to look for tachyons (particles going faster than the speed of light), but they have never been reliably discovered. \n\nThere are postulated entities called wormholes that might enable this kind of travel. Of course, we have no evidence for them at all.\n\nHowever, our understanding of physics is still very crude. We do not understand dark matter. Unifited field theory is still unproven. Even if it is proven, we do not understand the consequences of it (a lot of technology came from unifying electricity and magnetism). We do not understand what happens in black holes. We do not understand how the quantum world and gravity fit together. Even in quantum electrodynamics, which is viewed as settled and accepted, we end up performing illegal mathematical operations to get answers that agree with experiments. The role of the observer in quantum mechanics is not understood. We do not understand quantum teleportation very well. We do not understand BCS theory and its instantaneous coupling very well. We do not understand the apparent accelerating expansion of the universe (a sort of anti-gravity). There are immense holes in our understanding. Therefore, I would not be too confident that our current physics means very much here. \n\nThe only way to address this, is to continue to enhance our basic understanding of the way the physical universe operates. This might not be as romantic as it appears in the movies, but the hard work has to be done.
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)
600967
No there is no 'summation' of speeds involved with light.  Light is Electro-Magnetic Energy, although light travels as particles as well as waves.  In this Universe the speed of light is a constant, roughly 186,000 miles-per-second, or 300,000 km/sec or 300 Mega-Metres / sec.  Unless some POWERFUL external force acts upon light, it cannot change speed.  This entails the gravity of black-holes and such. (Not even light can escape from them.)\n\nA vehicle might weigh somewhere in the neighbor-hood of 3,300 lbs. (Approximately 1,500 Kg, for those of you who have not learned to count properly, just yet ...)\nCheck out da' math ...\n\n60mph = 100 kmph = 27.77r mps. \n(1,500 Kg x 27.77r mps) / 9.81 mps = ~ 4,246 N\n\nI doubt, very seriously, that a little over 4,000 Newtons is enough force to even put a dent in the factor of light-speed.  For more info, look-up Einstein's Theory of Realtivity' (Although I believe 90% of it to be short-sighted ancient crap ...)  This subject is covered in it ...\n(umm covered in Einstein's Theory, not copvered in crap .. which err .. is the same thing at times ...
64217
to answer your question it is possible to go faster the the speed of light. The speed of light is 186,000 miles per second.\n\nIf zooming beyond the local speed limit is punishable by law, then some scientists may have a gargantuan speeding ticket to pay. \n\nIn a controversial experiment reported in this weeks journal Nature, scientists at the NEC Research Institute in Princeton, New Jersey claim to have broken the ultimate speed limit -- the speed of light. Though hotly contested, some say this achievement could dramatically increase the speeds at which we can send and receive information. \n\nTaught in physics classes the world over, Albert Einsteins theory of special relativity holds that no object or information can move faster than the speed of light in a vacuum, or 186,000 miles (300,000 kilometers) per second. But NECs Lijun Wang says he created an experiment in which a light beam raced through a gas-filled chamber so quickly, it exceeded the speed of light by a factor of 300. Whats more, the light pulse appears to have left the confines of the chamber before it even entered a seemingly impossible occurrence according to theories of causality, which predict that causes must always precede their effects. \n\n"It sounds crazy, but this can actually occur," said Raymond Chiao, a physicist at the University of California at Berkeley. Chiao, one of a group of researchers who have been working to break the speed-of-light limit, explained that although a common object such as a baseball could never be flung faster than the speed of light, pulses of energy with certain complex properties have been known to bend the rules. \n\n\n\n"It sounds crazy, but it actually can occur." \n\n\n\n\nIn fact, several recent experiments, including one done by Chiao earlier this year, have pointed to energy pulses zooming faster than light speed. Yet each of these experiments has been encumbered by severe limitations on measurement or observation of the energy pulses. In contrast, this latest experiment is being touted by some as the most dramatic example yet of light breaking its own speed barrier. \n\n"The effects are much larger and more spectacular" than previous observations, said Chiao. \n\nIn Wangs experiment, a pulse of light passed through a small chamber filled with atoms of elemental cesium. A light beam traveling through such a medium has two different velocities a velocity for the individual light waves in the beam and a group velocity for the entire beam. Oddly, some light waves in the beam can actually travel backward for miniscule amounts of time, creating a sort of "tail" behind forward-moving waves. As such, a light wave and its tail can leave the gas cavity at different times, creating the effect that the light beam has left the cavity before its even entered. \n\nConfused? Youre not alone. In fact, even scientists who are familiar with this area of study are unsure about the details of Wangs experiment. And many scientists said the experiments results are still open to interpretation. \n\nWilliam Happer, a physicist at Princeton University argued that several specific problems exist with the experiment, including the fact that pulses get distorted when passed through any media other than a vacuum, or empty space. In addition, he said Wang and his colleagues performed the experiment in a way that doesnt tell the whole story, and that it can be interpreted incorrectly. "This is anything but dramatic," said Happer. "If you look at the data, theres essentially no evidence that [the beam] is going faster than the speed of light." \n\nWhats more, most scientists agree that even if such a beam can be proved speedier than light, it would probably not be able to carry any information. Such a feat could conceivably allow data to be sent back in time, thus violating laws of causality and sending quantum physics into disrepair. \n\nOthers are more optimistic as to the possible
214563
The previous answer is wrong. There is absolutely nothing stopping your reference frame travelling near (or even at) the speed of light. Even if you were travelling at 0.999999% the speed of light, you would still observe a light beam travelling past you at c. This speed is a constant because the speed of light does not depend on the velocity of the object emitting the radiation (see Maxwells equations).
532772
nothing but light can travel at light speed.  the faster you go, the more energy it requires to accelerate.  at speeds that are close to the speed of light, you would need what is basically an infinite amount of power to accelate.  with current technology, it is impossible.  the only reason light can travel that fast, is because when it is created it is already traveling that fast.  it doesnt have to accelerate.
933622
Nothing is faster than light
25198
You can't be in a vehicle going the speed of light, because as objects accelerate they gain mass and a car going the speed of light would be insanely massive.
855043
It's all theory, we don't know if (something) can exceed the speed of light. I would argue that time would be void at that moment, but again it's my theory. Interesting thought though.
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.
72735
No it is not possible to travel faster than light because the equipment you try to use will not work. The fastest thing to probably work may be a fast car. But there is still no way to travel fater than the speed of light. Speed of light travels at about 7 miles per second. I hope this helps.
678688
It's not a yes or no question.\n\nCan one travel faster than the speed of light?  No.\n\nCan objects be moving away from each other at a relative rate faster than the speed of light?  Yes.\n\nMeditate upon this, and you may become enlighted, or enspeeded, or something...
50535
OK, first fo all Mr cliffx has it backwards.  As you continue to acellerate tworads the speed of light time will slow down for you and stay normal for everyone else.  Thus at that speeds you could travel 10000 lightyear in only 1 year, your lifetime, but thousands of years could pass on earth.\n\nIt has been theorized that time travel is posible but you could not simply accelerate to that speed.  Even if we could travel that fast the economical need would be currently beyond what any country has, even if they put all there funding into that one project.  but I am getting off the subject.\nOne theory is to travel into a black hole.  The gravetational field in a black hole is so strong that it has been theoryzed that even time cannot escape.  Thus if we were able to travel into a black hole we could use the captuered time there, so to speak, and transverse the timeline.\n\nThen there are ideas of actually traveling on light waves, lasers, to allow us to travel to the speeds necisary.  Of course then we could only travel to the time of how long that peice of machinery is on.  Also we would have to convert ourselvesinto an electrical signale, data (essicially transport), which would then bring up the promblum of measuring matter without moving it and blah blah blah.\n\nSummery, Yes it is possible to travel through time.  We just do not havet he knowledge and/or technology to do it yet.
193299
It would take infinite energy to accelerate you and your light fixture to the exact speed of light which would thus be impossible.  However, as you approach the speed of light, at ever greater fuel expenditure, your rocket ship would shrink in the direction of travel and you would become a "pancake" but not be aware of it.  When you turn on your light, the photons emitted straight ahead would travel at the speed of light, c.  Photons always travel at the speed of light in a vacuum.  it is not like shooting bullets ahead from a fighter plane where muzzle velocity is added to the speed of the plane.  Although Einstein's theories of relativity do apply to the plane and bullets as well as photons, the effects are almost undetectable at the very low velocities we ordinarily experience on earth.
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