41–50 of 55 posts
Earlier quoted context omitted.
My understanding is there are scientists working on quantum entanglement communication. If so, I'm not sure why you assert no information transfer. (Not a physicist.)
Isn't that just tamper-proofing, rather than FTL communication? ( http://www.newscientist.com/article/dn12786-quantum-cryptogr... )
Entanglement doesn't send information.
It just protects it by giving you a private one-time pad to use for cryptography.
Earlier quoted context omitted.
Almost, but spooky action is quite a bit spookier. Suppose you and your friend both agree to MAYBE wave a flag every day at 1200 GST, then communicate no further about it. The alien would always observe that either both flags are being waved, or both are not.
(My physics education is limited to some undergrad level classes, so sorry if my interpretation is erroneous) Could it be that spooky action has underlying causes that we can't tell yet? For example, reusing the flag metaphor- you and your friend decide to MAYBE wave a flag every day at 1200 GST, and then in practice it happens that every sunny day you both wave it (because hey it's sunny, everybody likes to go outsi…
Earlier quoted context omitted.
Almost, but spooky action is quite a bit spookier. Suppose you and your friend both agree to MAYBE wave a flag every day at 1200 GST, then communicate no further about it. The alien would always observe that either both flags are being waved, or both are not.
(My physics education is limited to some undergrad level classes, so sorry if my interpretation is erroneous) Could it be that spooky action has underlying causes that we can't tell yet? For example, reusing the flag metaphor- you and your friend decide to MAYBE wave a flag every day at 1200 GST, and then in practice it happens that every sunny day you both wave it (because hey it's sunny, everybody likes to go outsi…
Earlier quoted context omitted.
Almost, but spooky action is quite a bit spookier. Suppose you and your friend both agree to MAYBE wave a flag every day at 1200 GST, then communicate no further about it. The alien would always observe that either both flags are being waved, or both are not.
(My physics education is limited to some undergrad level classes, so sorry if my interpretation is erroneous) Could it be that spooky action has underlying causes that we can't tell yet? For example, reusing the flag metaphor- you and your friend decide to MAYBE wave a flag every day at 1200 GST, and then in practice it happens that every sunny day you both wave it (because hey it's sunny, everybody likes to go outsi…
Earlier quoted context omitted.
Except in the case of the top article,as far as I understand, information could in theory be transmitted thanks to time. A spin change can represent a 1 bit, and the lack of a spin change at a time can represent a 0 bit.
It can be used to share a cipher (one-time-pad) because you and I would know the arrangement of bits that the other person has, and no-one else would/could know. However the measurements on the qubit's are probabilistic, so we cannot control the arrangement of bit that we have. We will only know if the are correlated/anti-correlated.
Being able to send data across the Pacific at essentially the speed of light, which was uninterceptable, would still be a massive breakthrough. Work on "weak" measurements of superpostioned systems interests me to that end (http://en.wikipedia.org/wiki/Weak_measurement)
Earlier quoted context omitted.
> Then he didn't understand what you were asking. It can easily be faster than the speed of light because no information can be transmitted through this phenomenon. If its observable then how could information not be transmitted? I'm the furthest thing from a physicist but if quantum entanglement causes an atoms polarity to change because millions of miles away another atom it is entangled with did the same, that wou…
It's like you and a friend have a deck of cards. You each take a card from the deck, and then travel a million miles away. Then, at the crack of noon (synchronized to GST, of course), you both look at your cards. Your card is the 3 of Clubs. You travel back to meet your friend, and discover that his card (which he measured at noon, just like you) was the 7 of Diamonds. You repeat this experiment a gazillion times and…
Thusfar that isn't the case - so it does seem to be spooky action at a distance. It's not just an inability to perform a suitable measurement beforehand.
Everyone here is getting confused by the fact that you cannot control the polarity/polarization of the qubits before/as you send them. This means that one cannot send information faster than light. What is useful however is the fact that when you send entangled qubits very far away, and measure them is the fact that the results of the measurements are always correlated/anti-correlated. As an example. Alice has a pair…
Earlier quoted context omitted.
(My physics education is limited to some undergrad level classes, so sorry if my interpretation is erroneous) Could it be that spooky action has underlying causes that we can't tell yet? For example, reusing the flag metaphor- you and your friend decide to MAYBE wave a flag every day at 1200 GST, and then in practice it happens that every sunny day you both wave it (because hey it's sunny, everybody likes to go outsi…
I believe that would be labeled a hidden-variable theory, which have apparently been mathematically eliminated from consideration.
Everyone here is getting confused by the fact that you cannot control the polarity/polarization of the qubits before/as you send them. This means that one cannot send information faster than light. What is useful however is the fact that when you send entangled qubits very far away, and measure them is the fact that the results of the measurements are always correlated/anti-correlated. As an example. Alice has a pair…
Can you explain the one-time pad application a bit more? It seems to me that if Alice and Bob can share a bunch of entangled qbits, they could just as easily share a classical one-time pad. What am I missing?
In a classical bit stream, ie loads of photons in a fiber or a radio wave, Eve can intercept 10% of the signal without Alice or Bob knowing, and she can recreate and send that 10% perfectly.
Alice and Bob can publicly announce measurement bases and a few of the bits to see if the line was touched.
Everyone here is getting confused by the fact that you cannot control the polarity/polarization of the qubits before/as you send them. This means that one cannot send information faster than light. What is useful however is the fact that when you send entangled qubits very far away, and measure them is the fact that the results of the measurements are always correlated/anti-correlated. As an example. Alice has a pair…
Can you explain the one-time pad application a bit more? It seems to me that if Alice and Bob can share a bunch of entangled qbits, they could just as easily share a classical one-time pad. What am I missing?