we cannot transfer information faster than light yet by any means, including quantum entanglement.\n\nhowever certain "type" of information can be transported.\nsee the thought experiment below --\n\nAlice and Bob seperated by 1 light year and keeping a couple of entangled pairs of photons can communicate information about what was the spin of the first pair when one of them collapsed the wave function.\n\n\nthus certain "type" of information can be transmitted. the information that can be transmitted is of the "chance" type.\n\nyou can transmit the outcome of a "roll of dice"\n\nif Alice gets spin up....Bob will get spin down. \n\nwhile alice/bob cannot control the outcome....they have the information regarding the outcome instanteously.\n\nisn't this some sort of instaneous "information transfer"?
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This is the kind of question I like ... :-)\n\nNo, this is not information transfer. I will try to enlighten the problem by formulating it more precisely.\n\nBut first, I'd like to show that if you could tranfer information faster than light, you'd get a contradiction with special relativity.\n\nSuppose A can communicate some information faster than light to B. Let A sending the information be event 1, B receiving it event 2. If the message is travelling faster than light, it can be shown that in the reference frame of A, event 1 happens _before_ event 2, while in the reference frame of B event 1 happens _after_ event 2, which is a contradiction because Bob cannot receive the message before Alice sends it. If a light-signal cannot travel between events 1 and 2, we call them spacelike separated (at least in some other languages than English we do :-) ). Spacelike separated events don't have a definite temporal order (the order depends on the reference frame).\n\nOf course, in your example there is a correlation between the outcome of Alice's and Bob's measurement, but it cannot be considered information transfer. They always knew that they would get opposite results, but they didn't know who would get |up> and who would get |down>. Information transfer would mean that Alice already has a piece of data she knows, eg. a bit of 1, and she would like to transfer it to Bob. Bob's gaining knowledge of this information is the result of Alice's sending it. So there is a definite temporal order (and causal relationship) between these events. In the entagled particle-pair example she doesn't have this piece of information before she does a measurement.\n\nHowever, you could say that A can transfer information like this: she does a measurement, and as the result of the measurement the wave function of both particles collapses, and B can measure to see if his particle is in a collapsed (|up> OR |down>) or superposed (|up> + phase_factor*|down>) state. So B will know if A has already measured or not! But B cannot decide which state the particle was in with only one measurement! And he can make only ONE measurement, because the measurement collapses the state. As a result he will always get either UP or DOWN, so he cannot tell if the original state was |up>+|down> or one of |up> or |down>.\n\nOf course if B could copy the state of his particle, he would be able to make multiple measurement on the same quantum-spin-state, but he cannot copy the state because of the no-cloning theorem (Zurek-Wootters, Nature, 1983 if I remember well, but anyway, see it on Wikipedia). Of course, if he would be able to copy the state, we would get a contradiction with special relativity.\n\nAs satanorsanta pointed out there are still problems with the _interpretation_ of quantum mechanics (especially with the measurement postulate), but I wouldn't consider this specific question unsolved.\n\nI know my English is not the best ... I hope you will understand my reasoning. If you's like to chat about these thing, send me a mail.
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at the atomic level, there is indeed randomness. you can predict the probabillity that things will occur, but cannot know for sure unless you make a measurement, which messes up the experiment because you "contaminated" the experiment with whatever you used to measure it. for instance, if you shine a flashlight at a double slit, half the light will go through 1 slit and half will go through another. however, if you turn down the output of the flashlight to 1 photon at a time, then the same thing happens. you cannot predict which one it will go through, it is completely random.\n\noh, and quantum theorry has been proven correct, better than any other theory out there - like newtonian physics, which have been shown to be approximations of the more accurate quantum theory.
142165
Yes, any object can, in theory, be treated as a single "state" that is scattered from some potential, with some probability that it ends up in a given direction.  Of course, for an object (such as a billiard ball) of macroscopic size, the only final states with any reasonable probability are those for which the result is near "classical".  And writing the initial state of a collection of ~10^23 particles that make up a macroscopic object as a single state (without approximation) is essentially impossible.\n\nIn other words, you COULD treat an everyday collision involving macroscopic objects as a quantum scattering problem, but you'd certainly be better off with classical mechanics for such situations; the probability of the actual result deviating from the classical result by even a tiny amount is pretty much zero.
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Your example is actually a good one for how we know no one can travel faster than the speed of light.  The people on the boat would measure the same speed for the beam of light as those standing on the shore.\n\nEinstein's theory of special relativity states that, regardless of your motion, light's speed remains constant.  Space and time warp in order to make light's speed constant from all perspectives.  As matter gets closer and closer to the speed of light, space stretches and time contracts, requiring infinite energy to reach the speed of light.  Only things with no mass (i. e. energy only) can travel at the speed of light, and nothing we know of can go faster.\n\nHowever, Einstein's theories do suggest that we could bend space and time to allow us to get around the speed of light.  We can't travel a trillion miles per second, but, with enough energy, we could shift some spot a trillion miles away to right next to us.
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The problem is that there are not two wavefunctions for entangled particles. There is only one, but that one wave function describes *both* of the particles. So the observation collapses that one wave function as fixes the state of the system. This is one difficulty of the 'particle' view of things. There is too much of a tendency to think of a two particle state as two one particle states. This is wrong.
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While photons don't have any force-mitigated interactions, there can be interference.  Matter (fermions) has the Pauli Exclusion Priniciple preventing, say, two electrons from being in the same spin-state in the same sub-orbital...there's a destructive interference term in the probability wave equation that comes from their half-spin states.  \n\nSimilarly, there's an inverse sort of "Pauli Inclusion Principle" for bosons (which have integral spin states and includes photons) to constructively interfere in the wave equation such that there's an increased probability for them to be in the same place at the same time.  \n\nOne might be able to, as you say, 'channel' this and force them to work together by creating an energetic population inversion of electrons ready to emit, then sending through a photon of the proper wavelength to produce a cascade of stimulated emission...Oh wait, that's a laser.
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with the same length of time??? possible but not probable....\n\n\nyou see according to einstein theory of relativity, the speed of light is the speed of near perfection....and it is not that easily attainable unless you have a force of a large magnitude...\n\n\n\nonce you travel that speed you can travel into the future for about a split second..\n\n\n\na more probable situation would be try getting sucked into a blackhole, and you'll speed up to the speed of light...\n\n\n\ncompare a blackhole to a sinkhole, a typical hole in your kitchen sink...fill it up with water but cover the hole...\n\nthen release the cover..the water will get sucked down into the hole...obviously the water will end up somewhere, right??? just like anything sucked up by a blackhole, it would eventually end up somewhere in the time-space dimension... and they call it the whiteholes.... and quantum physicists say that when you let your right hand get sucked into the black hole and ends up on the other end(white hole)..you'll notice that your right hand exist a micro second earlier than your left hand...(assuming your whole body doesn't get sucked up into the black hole)..\n\n\nback to your question...hehehe... getting sucked up in a blackhole will give you a speed equal or nearly equal to the speed of light...
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Well this one is interesting.  Mathematics tell us that to move in time, one must move faster than the speed of light.  There are particles that do move that fast so it is theoretically possible.\n\nWith that having been said, I'll go back to the particles that move faster than light.  These particles cannot be seen or measured in any way that we can figure out but we know that they exist because of the reaction of other things.  ( its like the wind blowing,  you dont see it but trees and stuff react to it )\n\nOne theory suggests that if we do manage to travel back in time,  we wont be able to interact with it at all. ( I dont understand all the mechanics on this one)  But it would be like being an invisible ghost.  You could observe things and events but couldnt make actual physical contact with anything thus you couldnt change events.
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There is a little research and some guy even wrote a book claiming that teleportation is feasible.  But don't buy your home teleportation machine yet.  As yet the only thing that has been transported is a few laser beams.
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im not sure if i know what youre asking. but from what i understand from my QM class, for question 1 youre right. as in the double slit experiment. when they shot electrons at it, there was a wave pattern on the screen but when they watched the slitz there wasnt. the whole thing behind this is tht by watching it, they changed somethin in the situation and cause it to be just a particle pattern. so in theory if there was an infinitely efficient watcher, then thye could see that the elctron goes through both slits and makes a wave.\nthe 2nd question, the whole theory about quantum mechanics is that nothing is definite. its a probability distribution for everything. but just some items   have a 100% probability of being in 1 spot. as in say you have a pen in your hand   then the pen has a 100% probability of being in your hand and 0% everywhere else. but for an electron, you cant see it and since it wont stop moving  there is a different probability for it. theres a probability of say 40% of the electron being over there and 60% of it being here. or somethin. and i dont know what the earthquake thing meant. but i guess the probability distribution they calculated did a really bad job and the QM probability theory could also have done a really really bad job but nobody would know since electrons cant be measured yet (i think)
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Laws sometime are not able to solve entanglement problems.\nThe solution would be basically from an atorney and between atorneys.\nSo the advice is see a professional atorney.
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No.\n\nThere is something often called "quantum teleportation," but it is much more analgous to a fax machine which send a set ot particle properties from one subatomic particle or atom, to another subatomic particle or atom. This is imporant work and will likely impact things like cryptography, but, despite the name which appears in popular accounts it is NOT teleportation in the Star Trek sense.\n\nEven in star trek they realize that it is fundamentally impossible to identify the position and location of each particle in a person accurately enough to be able to reconstruct it - hense the 'heisenberg compensator' they mention in some of the more recent shows.\n\nAlso the amount of energy in something the size of a person is enormous, more than all the nuclear weapons we have. (I'm guessing, but it is in that range.)\n\nSo, no, I would hope no one is working on this. At best, someone can be working on the physics which will lead to the physics that leads to the physics underlying such a device. Assuming such a device is even possible.
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The first website gives a good overview with no math, if you already understand light/waves/atoms skip to the part that I put in paranthesis.\nThe third site is a more advanced and goes more into the consequences.  In case we have different ideas of what laymen are.\nHere's a quick summary:\nquantum entanglement is when one photon of light is split into two equal photons of opposite polarity (direction of the wave disturbance) .  The two photons seem to be linked in a way that is currently innexplicable but demonstratable using interference patterns.  Which I hope you don't consider techno babble, but if you do, just ask what interference patterns are and I'll answer that, too.  That's a quick expanations of what's happening.\nUnless you mean why, the last site does a pretty good job of explaining that we don't really know, but we're trying pretty hard to figure it out.  There are many theories right now.  It'll go over a couple of them.(it's really an excellent paper.  I don't know what level of physics education you have, but it was perfect for me.I'm not a physicist, I'm a chemist.)
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A photon will keep going until it gets absorbed.  By the essense of your question, I am guessing that you are thinking of photons in terms of a solid particle.  True, it can be thought of as a particle, that is part of wave-particle duality.  But the truth is, we cannot really understand wave-particle duality in an intuitive way.  The mathematics are well understood, but as humans we cannot really grasp, it does not make sense to our everyday experiences.  Don't think of it as a particle disappearing.  A photon is merely a means of transmitting energy.\n\nMaybe this will help:  An atom is in an energized state with an electron in a higher orbital.  The electron drops to the ground state and a photon is emitted.  That photon travels either 10 nanometers or one light year (doesn't matter) until it interacts with another atom of the same kind.  That second atom absorbs the photon and an electron gets excited to the same state as the electron in the orginal atom.  So in this sense a photon is just a means of transferring energy.  No matter is created or destroyed.
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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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When one end of the unbreakable cable felt a tug, the force would be transfered along the cable to the satelite. When the cable is close enough the a blackhole, the acceleration at one end would cause the cable to break.. despite unbreakable. This is because the force cannot be transmitted fast enough along the cable... one end would be moving so fast while the other end barely felt the force yet and hence has not started moving.\n\nBlackhole is a very dense matter. So, it's straightforward to think that after the whole string is "in" the blackhole, they are condensed into very very dense form. However, is this so? Nobody can tell as known physical laws cannot be extended into this singularity in spacetime.\n\nIt might be a lame answer but I have to say it. The above situation cannot arise because there simply can be no unbreakable cable. Just like in QM... what if I know the velocity and position of an electron exactly. It's interesting to know what will happen, but QM tells us, u cannot know it. So, even though it is interesting to know it, it's beyond the domain of our universe. Yes, if it exist, it'll break the laws of logics in our universe..... but that's exactly why it does not exist..... because logic is consistent. Logic itself prevent such situation from arising. Know what I mean?\n\nAnyway, even if the cable is unbreakable... what about the part of the satellite it is tied to? Let's just imagine the cable and the satellite are unbreakable, then the blackhole would simply stretch the cable infinitely long without breaking it... allowing time for the force to "flow" thru the whole cable to accelerate the satellite. Is it reasonable to think of sth that can be stretch infinitely but would not break? Or u can set another rule that the cable cannot be stretched at all. This would then violate the rule of special relativity, that nothing can travel faster than the speed of light, as the force would be transfered to the satellite instantaneously.
485388
(1) there is no problem with the concept\n\n(2) the concept refers not to "a wave of particle". But to the fact that the wave IS the particle, and the particle IS the wave.  More precisely, the particle (in our everyday definition, i.e. a small bit of matter) does not really exist at a precise point in space, but it is to be found in a given region, and the probability of finding it there is proportional to the absolute value of its "wave function"\n\nyou seem to view this as little bits of matter / light undulating on top of a wave - that's wrong.\n\n\nhistorically, what happened is that various experiments seemed to suggest that SOMETIMES it seemed that you had a wave, and other times, a particle.\n\nThe most famous one is the double slot experiment.  Incoming light will go through the two slots, and lights re-emitted after having gone through each slot will interfere with each other, and on a screen you will observe an interference pattern, i.e. a series of bright and dark bands.\n\nso then someone suggested to use light of such low intensity so that you'd literally emit one photon at a time.  Hoping to not get any interference picture - since each photon could not interfere with anything.\n\nbut what happened was that the photons would arrive at various points on the screen, and little by little, their accumulation would reconstruct the interference picture\n\nthis is what caused people problems - until they invested quantum physics, which deals perfectly with this.