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New method of quantum entanglement increases the information that can be carried

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Re: New method of quantum entanglement increases the information that can be carried

#11

Post by moron4hire »

teraflop wrote: post #4
jackinloadup wrote: post #3

I wonder how long before we see major internet nodes connected via quantum entanglement.

Entanglement can't be used for communication. https://en.wikipedia.org/wiki/No-communication_theorem

I don't understand the limitation that "neither Alice nor Bob is allowed, in any way, to affect the preparation of the initial state." Why shouldn't Alice create the initial state?

If we can use the quantum entanglement to determine if some Eve has intercepted a message between Alice and Bob, then why can't we use the fact of tampering as the data pipe? Why shouldn't Alice create the initial state and Bob use the quantum entanglement to communicate back? Use two constant photon streams between the two, one from Alice to Bob, one from Bob to Alice. The photons that are emitted are identical--it's notionally a carrier wave. Alice checks to see if Bob "tampers" with the photons. The actual data encoded in the photon itself isn't important.

Say I fire a laser beam to the Moon. It's going to take a second and a half to get there. I send one half of my entangled pair to the Moon and I send the other half down a fiberoptic delay line. In 1.5 seconds, I start checking whether or not my entangled photons have been tampered with, and that is the data stream back from the moon.

Re: New method of quantum entanglement increases the information that can be carried

#12

Post by ikeboy »

omnipedal wrote: post #9
teraflop wrote: post #4

Earlier quoted context omitted.

Entanglement can't be used for communication. https://en.wikipedia.org/wiki/No-communication_theorem

They already teleported information via similar means, so I would hope this doesn't mean FTL communication is impossible.

It does mean that, actually.

Re: New method of quantum entanglement increases the information that can be carried

#13

Post by ikeboy »

moron4hire wrote: post #11
teraflop wrote: post #4

Earlier quoted context omitted.

Entanglement can't be used for communication. https://en.wikipedia.org/wiki/No-communication_theorem

I don't understand the limitation that "neither Alice nor Bob is allowed, in any way, to affect the preparation of the initial state." Why shouldn't Alice create the initial state? If we can use the quantum entanglement to determine if some Eve has intercepted a message between Alice and Bob, then why can't we use the fact of tampering as the data pipe? Why shouldn't Alice create the initial state and Bob use the qua…

>If we can use the quantum entanglement to determine if some Eve has intercepted a message between Alice and Bob, then why can't we use the fact of tampering as the data pipe?

You can't; quantum key distribution requires a classical channel as well. See https://en.wikipedia.org/wiki/Quantum_key_distribution#BB84_...

>After Bob has measured all the photons, he communicates with Alice over the public classical channel.

Edit: also, "I don't understand the limitation that "neither Alice nor Bob is allowed, in any way, to affect the preparation of the initial state." Why shouldn't Alice create the initial state?"

If Alice creates the initial state, she can send a message encoded within.

Re: New method of quantum entanglement increases the information that can be carried

#14

Post by omnipedal »

ikeboy wrote: post #12
omnipedal wrote: post #9

Earlier quoted context omitted.

They already teleported information via similar means, so I would hope this doesn't mean FTL communication is impossible.

It does mean that, actually.

https://en.wikipedia.org/wiki/John_G._Cramer

This guy seems to believe otherwise and many other scientific breakthroughs were declared as impossible before they were done, it is unwise to cling to limiting beliefs like that as that kind of attitude prevents technological advancement.

In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well.

Re: New method of quantum entanglement increases the information that can be carried

#15

Post by ikeboy »

omnipedal wrote: post #14
ikeboy wrote: post #12

Earlier quoted context omitted.

It does mean that, actually.

https://en.wikipedia.org/wiki/John_G._Cramer This guy seems to believe otherwise and many other scientific breakthroughs were declared as impossible before they were done, it is unwise to cling to limiting beliefs like that as that kind of attitude prevents technological advancement. In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well.

All his experiments have failed. See https://faculty.washington.edu/jcramer/NLS/NL_signal.htm

People have been trying to use QM to show FTL communication since QM was discovered, it doesn't work.

>In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well.

Yes, you can speculate whatever you want, that doesn't make it any truer.

Re: New method of quantum entanglement increases the information that can be carried

#16

Post by omnipedal »

ikeboy wrote: post #15
omnipedal wrote: post #14

Earlier quoted context omitted.

https://en.wikipedia.org/wiki/John_G._Cramer This guy seems to believe otherwise and many other scientific breakthroughs were declared as impossible before they were done, it is unwise to cling to limiting beliefs like that as that kind of attitude prevents technological advancement. In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well.

All his experiments have failed. See https://faculty.washington.edu/jcramer/NLS/NL_signal.htm People have been trying to use QM to show FTL communication since QM was discovered, it doesn't work. >In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well. Yes, you can speculate whatever you want, that doesn't make it any truer.

It's only 2015, I think it's a little ridiculous to make far sweeping conclusions about whole realms of science supposedly not working based on limited current understanding of science.

Re: New method of quantum entanglement increases the information that can be carried

#17

Post by ikeboy »

omnipedal wrote: post #16
ikeboy wrote: post #15

Earlier quoted context omitted.

All his experiments have failed. See https://faculty.washington.edu/jcramer/NLS/NL_signal.htm People have been trying to use QM to show FTL communication since QM was discovered, it doesn't work. >In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well. Yes, you can speculate whatever you want, that doesn't make it any truer.

It's only 2015, I think it's a little ridiculous to make far sweeping conclusions about whole realms of science supposedly not working based on limited current understanding of science.

We've known about QM for 80 years. It's given accurate predictions for all that time. What exactly do you think is limited in currnt understanding of science?

Re: New method of quantum entanglement increases the information that can be carried

#18

Post by Retra »

omnipedal wrote: post #16
ikeboy wrote: post #15

Earlier quoted context omitted.

All his experiments have failed. See https://faculty.washington.edu/jcramer/NLS/NL_signal.htm People have been trying to use QM to show FTL communication since QM was discovered, it doesn't work. >In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well. Yes, you can speculate whatever you want, that doesn't make it any truer.

It's only 2015, I think it's a little ridiculous to make far sweeping conclusions about whole realms of science supposedly not working based on limited current understanding of science.

It is only 2015, and the conclusions you reach must make sense according to what is known in 2015.

And our current understanding of science is only limited in comparison to wild speculation. Those limits also happen to be the strongest point in its favor.

Re: New method of quantum entanglement increases the information that can be carried

#19

Post by omnipedal »

omnipedal wrote: post #16
ikeboy wrote: post #15

Earlier quoted context omitted.

All his experiments have failed. See https://faculty.washington.edu/jcramer/NLS/NL_signal.htm People have been trying to use QM to show FTL communication since QM was discovered, it doesn't work. >In fact, it can be speculated that messages could be sent in the future as well as in the past, and other parallel universes as well. Yes, you can speculate whatever you want, that doesn't make it any truer.

It's only 2015, I think it's a little ridiculous to make far sweeping conclusions about whole realms of science supposedly not working based on limited current understanding of science.

Scientists know very little about QM despite it being known for 80 years due to political, resource and human IQ restraints. The human knowledge in this area is not even in infancy yet.

The experiments on Quantum Entanglement have only begun to intensify in recent years. With the advent of AI and commercial interest in the field due to communication opportunities, this may change rapidly.

When you say FTL communication is impossible that is a mere speculation at best, and a remarkably short sighted and laughable one in retrospect to paradigm shifts in the history of human technology. Scientific conservatism like that is a silly and shameful attempt to signal high status, which has held back human progress many times in the past. FTL communication is a major necessity and this field needs to be explored and pushed into hard without being held back by naysayers with dubious motives.

Re: New method of quantum entanglement increases the information that can be carried

#20

Post by therein »

ikeboy wrote: post #13
moron4hire wrote: post #11

Earlier quoted context omitted.

I don't understand the limitation that "neither Alice nor Bob is allowed, in any way, to affect the preparation of the initial state." Why shouldn't Alice create the initial state? If we can use the quantum entanglement to determine if some Eve has intercepted a message between Alice and Bob, then why can't we use the fact of tampering as the data pipe? Why shouldn't Alice create the initial state and Bob use the qua…

>If we can use the quantum entanglement to determine if some Eve has intercepted a message between Alice and Bob, then why can't we use the fact of tampering as the data pipe? You can't; quantum key distribution requires a classical channel as well. See https://en.wikipedia.org/wiki/Quantum_key_distribution#BB84_... >After Bob has measured all the photons, he communicates with Alice over the public classical channel.…

I was thinking of that too. Do you think that would add additional latency as the entanglement needs to boot and initialize? It also feels like we would be wasting some bandwidth because the tampering of the pipe will give us 1-bit of information rather than the pipe providing us with four.

But hey, it is FTL anyway.

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