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Mathematical Breakthrough Sets Out Rules For More Effective Teleportation
dsinc sends this news from the University of Cambridge:
"For the last ten years, theoretical physicists have shown that the intense connections generated between particles as established in the quantum law of ‘entanglement’ may hold the key to eventual teleportation of information. Now, for the first time, researchers have worked out how entanglement could be 'recycled' to increase the efficiency of these connections. Published in the journal Physical Review Letters, the result could conceivably take us a step closer to sci-fi style teleportation in the future, although this research is purely theoretical in nature. ... Previous teleportation protocols have fallen into one of two camps, those that could only send scrambled information requiring correction by the receiver or, more recently, "port-based" teleportation that doesn't require a correction, but needs an impractical amount of entanglement – as each object sent would destroy the entangled state. Now, physicists from Cambridge, University College London, and the University of Gdansk have developed a protocol to provide an optimal solution in which the entangled state is 'recycled,' so that the gateway between particles holds for the teleportation of multiple objects. They have even devised a protocol in which multiple qubits can be teleported simultaneously, although the entangled state degrades proportionally to the amount of qubits sent in both cases."
Bit optimistic, aren't we?
Suppose I teleport an object from a height of 1000 feet to a height of 0 feet about sea level. There has been a loss of gravitational potential energy -- where does this energy end up? Conversely, if teleporting the object to a higher elevation, how is the gravitational PE imparted to the system?
Is that you, Bones?
They say the first thing to go is your penis. Well, it's either that or your brain. I forget which...
This one is even better so far, half of the comments are retarded trying to be serious.
For now it is math. Whether it is really relevant for real world physics is a totally different question.
"LOL but on Slash, sci-fi is real. Space elevators, warp drives, Mars colonies and the hundreds of attendant magical technologies and fantasy materials are just a question of, like, how hard we really want them to happen."
And remember Dick Tracy's video wristwatch was described in the 1930s when radio and telephone was less than 50 years old. We have it now and in other forms such as cell phones and tablets less than 75 years later. Slashdot is visited by people in research and science fiction, who knows what could be in the next 100 years if we put the "old nose to the grindstone".
IF countBeingsInChamber > 1 THEN GOTO abort_transfer
This is really serious science. And it doesn't allow to transmit information faster than light. You still need to send classical information to the other side. It's just that instead of correcting the state, the information tells the other side which of the many qubits is in the right state.
As a simple (but not completely accurate) analogy, imagine you've generated a one-time pad, which is shared by Alice and Bob. This shared one-time pad represents the entangled state.
The original teleportation scheme can then be roughly compared to the normal operation of the one-time pad: Alice encrypts her bit and sends the encrypted bit to Bob. Now Bob has to explicitly decrypt the bit.
The port based teleportation scheme allows Bob to not do any calculation, by Alice just telling Bob which of the bits in his copy of the one-time pad already agrees with the bit she wanted to send. However the old scheme had the disadvantage that it destroyed the complete OTP for sending the single bit.
This is a scheme which allows to reuse the same OTP (minus the already-used bits) to transmit further bits.
The point where the analogy fails is that the original data to transmitted are qubits, while the encrypted data sent consists of classical bits. Which is the reason that teleportation is actually interesting because you cannot simply convert an unknown quantum state into classical information; indeed the fact that quantum teleportation works is intimately linked to the fact that the state is "encrypted", that is, the classical bits alone don't tell you anything at all about the teleported quantum state, just like with an OTP the encrypted message alone don't tell you anything about the cleartext bits.
Also note that the "recycling" of entanglement doesn't mean that you end up with the same amount of entanglement as you started with. You just don't use up an excessive amount of it (in the OTP picture: You don't consume an entire large OTP to just send one bit; however your usable OTP still shrinks with each bit sent).
And of course it has to be stressed that, unlike the summary suggests, quantum teleportation is something completely different from Sci-Fi teleportation.
The Tao of math: The numbers you can count are not the real numbers.