It is off-topic, but I could not resist: I don't think that cameras and microphones have surpassed the human capabilities. Show me a microphone that has the same dynamic range as the human ear. Or a vision system that has the same 'postprocessing' capabilities as our visual cortex.
Resolution and sensitivity are not the only performance indicators!
Yes, big blue had an extensive knowledge about Kasparov's playing pattern, whereas Kasparov did not have the opportunity to learn something about big blue's way to play.
AFAIK, all of Kasparov's request for test games were refused.
For me, this is highly unfair and the proof, that a machine plays better chess than man, is not yet given.
I always thought I understood EPR pretty well, but this article puzzled me at first, as it claims it would allow faster than light communication and reverse causality (unlike with other EPR experiments).
In quantum entanglement you have to objects with an entangled quantum state. That is, one of their properties is always the same (or always the opposite, depending on the kind of entanglement). On the other hand, this property is not already fixed when the objects get separated. Only when you measure the state of one particle you actually stipulate its state, and due to entanglement the state of the other partcle as well. As this happens instantaneous an the objects might be separated by a great distance, you get this 'spooky action at a distance'.
But, as been shown before, since you have no influence on the outcome of the measurement, there is no data tranmission involved (and also no reverse causality).
The article claims, that one can actually set the state of one object at will, thereby forcing the other object to have the same predetermined state. The problem is, that while you can actually force a light beam to behave like a particle (when you look at it how it behaves as a particle) or to behave like a wave (when you look at it how it behaves as a wave), and this actually has an effect on the entangled beam, it is not possible to measure if a light beam behaves like a particle or a wave!
Let's say you make the two slit experiment and observe which slit the beam will choose (thereby forcing the beam to behave like a particle).
If you make the same experiment on the entangled beam, you will observe, that it will go through the same slit. (This is an ordinary EPR experiment without faster than light communication and reverse causality). If, on the other hand, you choose to look at the entangled beam as it behaves as a wave, it will behave as a wave. It still has both, the particle and the wave nature!
Unlike the spin, that could be either up or down, the particle or wave nature of a quantum object are two properties that coexists!
You are actually transport neither matter nor data, but an entangled quantum state!
The reason why this is always attributed with teleportation is very subtle.
Let me define 'teleportation' like this: A short process after which, an object X does no longer exists at place A, but at a distant place B.
In my understanding it is okay, if the object at place B is not object X, but an indentical
copy of it, as long as the object at place A ceases to exist.
One could now disasemble the object into atoms, while writing down the position and momentum of each atom. This information could be transmitted by radio to place B, and there one could reassemble the object from different atoms.
The only problem is, that we would also have to transmit the atom's quantum state in order to really obtain an identical copy. The problem actually already starts with measurement of position and momentum, as one can not measure both quantities with great accuracy (Heisenberg principle). Bottom line, you cannot possibly know everything about the object. It is just not possible, quantum physics wise.
What does guys did, was transfering the quantum state from the object to a different media, the photon. Since this photon was entangled with another one (at place B), one automatically als transfers the quantum state to this other photon, thereby teleporting the quantum state from A to B. The trick is not to measure the quantum state in order not to destroy it.
So, on one hand, one has apparently moved something from A to B in no time. (As it is neither matter nor data the theory of relativity is not violated. It is on the other hand also disputed, if you really have moved something).
This already can be called teleportation.
Furthermore, one could imagine, that one could use this technolgy to transmit more complex quantum states and eventually would be able to take of the entire quantum state of an object, disassemble transmitting an exact blueprint of the object by radio, reassemble the object and reapply the teleported quantum state, thereby having a really exact copy of the object and hence the whole thing could be called teleportation.
So they *can* eavesdrop, you'll just know if they do.
This is not actually true. If one could eavesdrop one could just as well retransmit the original message and therby hide your interception.
The big difference with quantum versus conventional encription is, that the information is immediately destroyed when you read it "the wrong way", i.e. using the wrong angle for your polarisation filter (in case of photons). This polarisation angle(s) act as some sort of key, it has to be known to the intented receiver. An eavesdropper can guess the key, but only *once*. There is no way to make a backup copy of a quantum state.
$.
I don't see why this is so much different to classical AFM's. First of all, it still is an AFM, only the force detection method is different. Secondly, not all AFM's use cantilevers and optics. There are in fact quite a few alternatives (e.g. tuning forks, piezo resistive cantilevers).
And still, even with classical cantilever and optics systems you can achieve much more than 60 lines per second (I first thought it supposed to be 60 frames per second). I worked with such a classical system, and it could scan at a rate of about 300 lines per second. This system was not specifically designed for high speed and was already considered outdated at that time (that was 1999).
It is true, that commercial systems are generally much slower than that. But it would surprise me, if one could not find a commercial system which can do 60 lines per second these days.
$.
Slashdot Mirror
It is off-topic, but I could not resist: I don't think that cameras and microphones have surpassed the human capabilities. Show me a microphone that has the same dynamic range as the human ear. Or a vision system that has the same 'postprocessing' capabilities as our visual cortex. Resolution and sensitivity are not the only performance indicators!
My point is, that we have not provably reached this milestone yet.
In chess it seems to be vital to know its opponent, and in this respect the competition was unnecessarily unfair.
For me, this is highly unfair and the proof, that a machine plays better chess than man, is not yet given.
In quantum entanglement you have to objects with an entangled quantum state. That is, one of their properties is always the same (or always the opposite, depending on the kind of entanglement). On the other hand, this property is not already fixed when the objects get separated. Only when you measure the state of one particle you actually stipulate its state, and due to entanglement the state of the other partcle as well. As this happens instantaneous an the objects might be separated by a great distance, you get this 'spooky action at a distance'.
But, as been shown before, since you have no influence on the outcome of the measurement, there is no data tranmission involved (and also no reverse causality).
The article claims, that one can actually set the state of one object at will, thereby forcing the other object to have the same predetermined state. The problem is, that while you can actually force a light beam to behave like a particle (when you look at it how it behaves as a particle) or to behave like a wave (when you look at it how it behaves as a wave), and this actually has an effect on the entangled beam, it is not possible to measure if a light beam behaves like a particle or a wave!
Let's say you make the two slit experiment and observe which slit the beam will choose (thereby forcing the beam to behave like a particle). If you make the same experiment on the entangled beam, you will observe, that it will go through the same slit. (This is an ordinary EPR experiment without faster than light communication and reverse causality). If, on the other hand, you choose to look at the entangled beam as it behaves as a wave, it will behave as a wave. It still has both, the particle and the wave nature!
Unlike the spin, that could be either up or down, the particle or wave nature of a quantum object are two properties that coexists!
The reason why this is always attributed with teleportation is very subtle.
Let me define 'teleportation' like this: A short process after which, an object X does no longer exists at place A, but at a distant place B.
In my understanding it is okay, if the object at place B is not object X, but an indentical copy of it, as long as the object at place A ceases to exist.
One could now disasemble the object into atoms, while writing down the position and momentum of each atom. This information could be transmitted by radio to place B, and there one could reassemble the object from different atoms.
The only problem is, that we would also have to transmit the atom's quantum state in order to really obtain an identical copy. The problem actually already starts with measurement of position and momentum, as one can not measure both quantities with great accuracy (Heisenberg principle). Bottom line, you cannot possibly know everything about the object. It is just not possible, quantum physics wise.
What does guys did, was transfering the quantum state from the object to a different media, the photon. Since this photon was entangled with another one (at place B), one automatically als transfers the quantum state to this other photon, thereby teleporting the quantum state from A to B. The trick is not to measure the quantum state in order not to destroy it.
So, on one hand, one has apparently moved something from A to B in no time. (As it is neither matter nor data the theory of relativity is not violated. It is on the other hand also disputed, if you really have moved something). This already can be called teleportation.
Furthermore, one could imagine, that one could use this technolgy to transmit more complex quantum states and eventually would be able to take of the entire quantum state of an object, disassemble transmitting an exact blueprint of the object by radio, reassemble the object and reapply the teleported quantum state, thereby having a really exact copy of the object and hence the whole thing could be called teleportation.
This is not actually true. If one could eavesdrop one could just as well retransmit the original message and therby hide your interception.
The big difference with quantum versus conventional encription is, that the information is immediately destroyed when you read it "the wrong way", i.e. using the wrong angle for your polarisation filter (in case of photons). This polarisation angle(s) act as some sort of key, it has to be known to the intented receiver. An eavesdropper can guess the key, but only *once*. There is no way to make a backup copy of a quantum state. $.
I don't see why this is so much different to classical AFM's. First of all, it still is an AFM, only the force detection method is different. Secondly, not all AFM's use cantilevers and optics. There are in fact quite a few alternatives (e.g. tuning forks, piezo resistive cantilevers). And still, even with classical cantilever and optics systems you can achieve much more than 60 lines per second (I first thought it supposed to be 60 frames per second). I worked with such a classical system, and it could scan at a rate of about 300 lines per second. This system was not specifically designed for high speed and was already considered outdated at that time (that was 1999). It is true, that commercial systems are generally much slower than that. But it would surprise me, if one could not find a commercial system which can do 60 lines per second these days. $.