...... infinite energy.   How come a photon which travels at a speed of light does not absorb all the energy in the universe?
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Since photons according to relativity interpretation are massless ,they cannot exist as a mass. \n\nSince photons is a mathematical invention which no one really knows what it is.\nHence cannot follow gravity laws.\nFor an entity to follow the laws of gravity ,Be Einstein's or Newton's , it must exist as a mass structure.\n\nYou question is very logical. It contradicts the reasoning that if a mass made up of atoms and when we apply power to make it move at the speed of light ,it will soak mass just like a sponge from its surrounding. Since mass is Energy according to relativity it will soak all the energy around it. \nSince as you say,    E=M *gamma *C^2  is infinite ,it makes sense that Energy would have to come from an infinite source.\n\nThey say mass increases with velocity.This has to.\n magically come from the inside of the atoms or is it a rain of mass that comes from the outside.The atoms become very massive, and at the same time shrink in dimension it the direction of motion only as they approach the speed of light.\n\nThese interpretation of Relativity are very difficult to make real sense out of it.\n\nThat brings to question is the theory of relativity misinterpreted  by scientists?. They did not understand it then,and I have my doubts about the present.Let alone really Understanding What Energy exactly represents!
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Hmmm...very theoretical of an answer you pursue there, my friend.\n\nSince our limted senses are not able to confirm our speculations, I shall speak in a dialect to the speculations only.\n\nThe matter and energy hols themselves in individual co-relation, and would cease to exist in this paradox without each other.\n\nThe Big Bang itself holds itself as a theory due to the sole fact, that the Universe is observed to have expanded, and it supports Einstein's theories as well. \n\nIn such an accordance, energy is prone to have evolved into matter, from Einstein's equation, which seems to be pretty logical, due to the colossal amount of energy at that point in time, that may have resulted in the formation of Universe.\n\nAs the theory goes, the 'infinite' amount of energy was existant for only a millisecond or so. It blast was followed by the formation of waves, which collapsed into miniscule particles we call photon, electron, and neutron and perhaps some other form of matter. This matter furthermore bonded together to give birth to the present Universe.\n\nWhat is actually amazing is the very fact, that all this occured in a few seconds. The forces took over and resulted in various formations, that we bear to our knowledge. We ourselves bear credit to such particles. The concept of life is a debatable query, yet it may hold itself in a form of energy as well. A sort of self-functioning energy that holds this matter in a co-ordinated existence. What we call memory, emotions and other fragments of our brain, could be a manifestation of this energy as well. Perhaps energy bears itself true to the 'spirit' as we address it. \n\nWhatever the matter, yet one factuality is in the least doubt. Matter cannot produced, nor destroyed, for just a creation or devastation would bear no fundaments to it, for energy holds itself responsible for every action. Such a creation/devastation would be like killing death. Heh he...\n\nTill next time, my friend, adieu!
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The universe, from your reference frame, would be length contracted into a single plane perpendicular to your direction of motion, thus enabling you to cross it by traveling no distance. Time for you would be stopped completely, thus you would travel this no distance in no time, at a speed of precisely c in your reference frame (light does that in every reference frame), despite the fact that by definition you are stopped in your own reference frame. Every other light ray would also travel at c in your reference frame and so would pass you in a finite period of time, except time would never move forward and so it wouldn't actually go anywhere. If you looked outside at the infinitesimally thin slice of universe, you would find that the area no distance ahead of your light ray is in the future of the origin (as viewed from any valid reference frame) and the area no distance behind it would be in the past. The beam you are riding on would have no frequency and would appear as a constant electric or magnetic field. Since the beam you are riding on is still traveling at c, it would therefore have infinite wavelength and so the field in question would permeate out to infinite distance in front of and behind you - not that it matters because there is no universe in either place. Speaking of the universe, every particle in it would appear to you to be infinitely massive and the universe would thus collapse on itself infinitely fast, if only there were time for it to do so.\n\nBy the way, there is a reason the speed of light is not considered a valid reference frame in special relativity. This is it.
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Wow, great question(s)!  You're brooding over something called the 'twin's paradox', read more about it in the link below.  Basically, what you're fretting over are a couple of the (wierd) implications of special (and general) relativity.  You (and what some others have said) are right, all velocity is relative, which comes from the simple fact that there is no special place that we can call 'still' which we could measure our velocity against.  The single exception to this lies in the speed of light, which is constant for everyone everywhere, no matter what their speed is relative to anything else.  (Note: light isn't special, the only reason it's able to travel at the upper speed limit is because it's particles, photons, have no mass.  Nothing with mass can ever travel AT the speed of light, only near if it is pumped up with huge amounts of energy.)  Think about the wierd implications of this; even if you were able to travel at 99.999999% the speed of light, and your friend would also be able to travel the same speed in the opposite direction, if you shined a light back toward your friend and could measure the photon's speed as they travelled between you the photons would STILL be travelling at the speed of light.  Ok, what does that mean?  The speed of light is just a speed, like any other, but is a constant that can not be exceeded.  Well, like any other speed, c (the usual symbol for the speed of light) is definded as the ratio of the distance travelled (call it 'x') by the time it took to travel it (call it 't'), or c=x/t.  But if 'c' can't change (because it's a constant) what is changing?  There's only two other things in the equation, x (the distance, a measure of space) and t.  Time and space enter into Einstien's equations here, the only way to keep c constant is for x and t to somehow collaborate to change together to make it so.  This is why time (and space) are so 'relavent' to velocity.  And as a matter of fact, time is 'relavent' to gravity as well, as Einstein pointed out so much better than I can.  For Einstein, the breakthrough came when he realized that there is no measurable way to distinguish between gravity and acceleration (a.k.a. the rate of change of velocity with respect to TIME), or more importantly, between the lack of gravity (say a person floating in space) and a particle (or person) in a falling box, they're indistinguishable.  From these two simple ideas (the constancy of c, and the equivalence of gravity and acceleration) Einstein formulated the theory of general relativity, one of the crowning achievements of human thought.  You ask good questions, keep wondering!
58074
Photons do not just have a very small, negligible mass, they have zero mass.\nA photon does however have momentum due to the fact that it is traveling at the speed of light.\n\nYou cannot apply a force to a massless object, therefore, Newtons 2nd law is of no use here.\n\nIt might also help to remember that a photon is just one way to look at the nature of light.  Not only is light a particle, it is also a wave, an electromagnetic wave, and you surely cannot apply a force to a wave.\n\nhttp://math.ucr.edu/home/baez/physics/ParticleAndNuclear/photon_mass.html
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Not sure that i can agree with Messrs Santras. Photons that do not have a mass? \nhmmm.. no mass, no energy, no time, no light. Anyway.. The  idea about photons that i find interesting are that they only have mass while they are moving. The mass disappears as a result of trying to observe it.\nMaybe the giving up of mass and the subsequent conversion of this mass to energy gives us the equal and opposite force to power...............TIME.\nAs for the rest of this question? Well if light is not electromagnetic then what is it? Are photons spots of energy or waves? This has been an argument for a long time. Maybe they are both. Each having their own laws to drive them.\nIf we consider the double slit experiments with light, we come up with some interesting results. One of which talks about the possibility that photons can communicate with each other! That there is some clandestine signalling goes on between a source of a photon and a recipient of a photon. This would have to happen at a super-light speed and therefore involve time travel of the signals! Maybe? The crux could be following the simplest form of physical law "the path of least resistance" how does a photon (light) know which direction is a straight line?\nPhoton theory isnt easy to think about. there are many established experiments out there to prove many things about photons but to manipulate photons in order to make something invisible? We would have to understand the fundementals of time, as yet this has not been achieved. We can only hope to observe its effect rather than it's mechanics.
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There are two types of particle in the universe. Those with a rest mass (ie a mass when they are stationary) and those with no rest mass. Only zero rest mass particles can travel at the speed of light.\n\nMeasurements have shown that the speed of light is the same however fast you are moving. This couterintuitive result is the basis for special relativity. It is fairly straightforward to show from this measurement that accelerating a particle with non zero rest mass close to the speed of light does not simply add to its energy but increases its mass. An infinite amount of energy would be needed to accelerate a particle with non-zero rest mass to the speed of light. This effect too can be measured in a lab.\n\nThe red shift does not have its origins in changes in the speed of light at all - in fact it relies on the speed of light being the same for all wavelengths of light. It is in effect the doppler effect for light - the same thing that makes the frequency of a passing car drop as it recedes.\n\nAnd it is perfectly possible - not even that difficult - to do measurements on the speed of light accurate to 8 or 9 decimal places.
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On the contrary, a light beam would merely percieve that it travelled instantly inbetween origin and destination. Space would be warped to Zero distance in the direction of travel, not Zero space. I know it seems like a sleight-of-hand trick with the mathematics, but the distinction is important.
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Light IS energy...sorry I can only think of one...:(
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Photons are produced by atoms when a bound electron moves from one orbital to another orbital with less energy. Photons can also be emitted by an unstable nucleus when it undergoes some types of nuclear decay. Furthermore, photons are produced whenever charged particles are accelerated.\n\nIn physics, the photon (from Greek φως, "phōs", meaning light) is the quantum of the electromagnetic field, for instance light. The term photon was coined by Gilbert Lewis in 1926.\n\n \nThe photon can be perceived as a wave or a particle, depending on how it is measuredThe photon is one of the elementary particles. Its interactions with electrons and atomic nuclei account for a great many of the features of matter, such as the existence and stability of atoms, molecules, and solids. These interactions are studied in quantum electrodynamics (QED), which is the oldest part of the Standard Model of particle physics.\n\nIn some respects a photon acts as a particle, for instance when registered by the light sensitive device in a camera. In other respects, a photon acts like a wave, as when passing through the optics in a camera. According to the so-called wave-particle duality in quantum physics, it is natural for the photon to display either aspect of its nature, according to the circumstances. Normally, light is formed from a large number of photons, with the intensity related to the number of them. At low intensity, it requires very sensitive instruments, used in astronomy or spectroscopy, for instance, to detect the individual photons.\n\nPhotons are commonly associated with visible light, but this is actually only a very limited part of the electromagnetic spectrum. All electromagnetic radiation is quantized as photons: that is, the smallest amount of electromagnetic radiation that can exist is one photon, whatever its wavelength, frequency, energy, or momentum. Photons are fundamental particles. They can be created and destroyed when interacting with other particles, but are not known to decay on their own.\n\nPhotons have zero mass and zero electric charge, but they do carry energy, momentum and angular momentum. Photons are always moving, and photons in a vacuum always move at the vacuum speed of light with respect to all observers, even when those observers are themselves moving. The energy and momentum carried by a photon is proportional to its frequency (or inversely proportional to its wavelength). This momentum can be transferred when a photon collides with matter. The force due to a large number of photons falling on a surface is known as radiation pressure, which may be used for propulsion with a solar sail.\n\nThe actual upper limit of the photon rest mass compatible with observations depends on additional assumptions. A conservative consensus limit of the Particle Data Group is 6×10-17 eV based on changes in magnetohydrodynamics which would contradict solar wind observations.\n\nPhotons are deflected by a gravitational field twice as much as Newtonian mechanics predicts for a mass traveling at the speed of light with the same momentum as the photon. This observation is commonly cited as evidence supporting Einstein's theory of gravitation, general relativity. In general relativity, photons always travel in a "straight" line, after taking into account the curvature of spacetime. (In curved space, such lines are called geodesics).
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Dan's answer is good. Kacey misunderstood the question and then got it wrong to boot; the speed of light is constant only in a vacuum. In materials it is slower, and slower in a prism than in air.\n\nBut you weren't asking about light bending in a prism, were you? You were asking about it bending in space, around a massive body.
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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
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Actualy, I am an expert in this field, having a Ph.D. in Optical Sciences.\n\nI don't believe light is a particle, exactly.  It is a quantization of energy, but not really like a particle.  If it were a particle it would explain how it can propagate across nothingness.  The existence of something in space would just get into its way, so the nothingness only helps light to propagate.  But a particle implies rest mass and other physical properties which light does not have.\n\nI don't believe that empty space is something, contrary to the way some people interpret Einstein.\n\nI don't believe it is action at a distance.  Light takes a finite amount of time to cross space.  The action occurs where the light is.\n\nThe question was more of a problem when light was considered to be merely a wave.  A wave needed a medium to disturb or propagate across.  Sound moves molecules about as it propagates.  But light only bears a resemblance to a wave in the way it behaves.  It is not like a classical wave.\n\nThe best way I can think of to explain it is to understand that an electromagnetic wave carries with it its own medium.  The electric and magnetic fields oscillate, feeding on itself, so to speak.  The energy is launched into space and perpetuates itself according to the laws of physics.
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A photon is a quantum of the vibrational energy of the space grid (as in the image above). At any one point on the wave, photons are produced out of the zero-point and then oppositely, photon holes are produced. Hence, it must be the case that these oscillations up and down come in discrete steps--or quanta.\n\n \n\nWhen a particle from the quantum vacuum acquires energy from a charged particle of matter, it may expand from the addition of this excitation energy to become an ordinary photon. Energy, therefore, expands the size of a virtual photon in ground state.\n\n \n\nA virtual photon, thus, is a "collapsed" short-range quantum that becomes an ordinary photon when given energy from an excited charged particle. Hence, the primary reason that we do not observe the photons that exist in the quantum vacuum, is because the quanta of space-time that compose the vacuum have a very minute amount of energy within them and are, therefore, too small to be observed directly. However, such vacuum quanta may become observable and measurable as ordinary photons after emission.\n\n \n\nWhen actualization takes place, we may measure photons and photonic energy hitting a measuring device.  But, while in-flight, we may not speak about photons at all, because technically speaking they are not photons.  So, when Planck's equation says that energy comes in lumps E = hf, this only refers to a state of an EM wave after an actualization or measurement has happened.  Prior to this we have only Kant's noumenal "wave" condition.  \n\nphotons must have higher frequencies, by exactly one hertz, than the expected difference of the energy levels of the electrons from which they received energy. Additionally, photon wavelengths must include a very long 3 x 10^8 meters to be added to all emitted wave fronts
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Yeah man...light is one of the most energetic forms that we witness. Light actually has many types of energy, just like most other things. \n\n1) Photons of light (of a suitable frequency are capable of imparting enough momentum to an electron in a metal so that the electron leaves the metal's surface. This is known as the photoelectric effect and the credit for it's knowledge goes to Mr.Einstein.\n\n2) Light has heat energy, and therefore thermodynamic value. You'll see that if you stand in the sun too long, you will be hot. \n\n3) The thermodynamic energy of light causes photochemical reactions, such as the radicalisation of halogen atoms, or the redox reactions of alkyl halides. \n\nI cannot be too sure of my satisfaction quotient with this answer because your question overlays so many fundamental concepts of light. For example, you wouldn't ask a rolling ball, "Excuse me sir, but how much energy do you really have?" The ball will snicker because you have not specified WHAT KIND OF ENERGY you want from the ball. Now, if you were to ask, "Excuse me sir, what is your KINETIC energy?", the ball would happily answer that it would be half of its mass multiplied by the square of its velocity. \n\nOne of the kinds of energy does involve a mass parameter and that would be the photoelectrical energy of light. This energy functions on the sound premise that linear and angular momentum are conserved, and since light has dual (mass-wave) nature, this kind of energy does involve mass. \n\nWe know that the energy of a photon of frequency v is E=hv where h is Planck's constant. We also know that the energy of a photon in relation to its mass is E=mc^2. THus we can say:\n\nmc^2 = hv.\n\nAll right, here is a clear answer, which I just realized. \n\nOne photon of light has the above mentioned amount of energy, and therefore a ray of light will have the energy of how many ever photons are in the ray of light. \n\nSo for n photons, energy of the ray of light is nhv. \n\nNow THIS nhv can be CONVERTED into all of the forms mentioned above. Light has energy which is capable of doing different kinds of work. \n\nForgive me for the error of thinking that light has different forms of energy. It has one form of energy which can be CONVERTED into different forms of energy. Phew....\n\nI really must thank you as this was a learning process for me too.\n\nAyerhs.
40042
Yeah I think you misread what scientists "say".  In the equation, the speed of light is inversly proportional to mass.  So the faster something is, the more infinitly small in mass it has to be.  Light is measured in particles called photons, that have 0 mass.  Since everything we see has a mass, it can never go the speed of light which has none.  Oh and is light really that fast?  It takes 8 minutes for a photon from the sun to get here.  And yeah, photons Smash into us all the time.  Its a whole quantum chemistry thing, but you can feel the warmth of the sun on your skin.  Thats cuz your being bombarded with light.
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We say that a photon is massless because it is in the usualy meaning of the word.  A photon has zero rest mass.  However, since it obviously has energy, it has a momentum.\n\nRead through this site and some of the related articles, I think it explains it very well,\nhttp://math.ucr.edu/home/baez/physics/ParticleAndNuclear/photon_mass.html