Wonder if Atlas has a hand in this

# Quantum Internet and Quantum Teleportation

**jedidia**#2

Just to clarify, âQuantum teleportationâ is not matter transport. Itâs the application of a state from one particle to an entangled partner. The two entangled particles had to have been together at some point, so this doesnât constitute superluminal communication either. Atlas seems to be way ahead in this field (well, no wonder, since they can get superlumina to send them research data from the futureâŚ).

Also, âQuantum internetâ and stuff usually refers to using quantum entanglement for save encryption, as in Quantum key distribution, the actual data transfer is still handled by digital data.

**Virakotxa**#3

This is crazyâŚ You just need to translate spins to binarie and you have instantaneous transluminal communication! Imagine the implications for space exploration! No *âInterstellarâ* time-dilation crap to deal with!

Is this real? Are the lines crossing!?

**Wickedobject**#4

Not only space, deep ocean. Perhaps global connected computer systems acting as one.

**jedidia**#5

Unfortunately, thatâs not how it works. First off, as mentioned above, the particles had to have been together at some point in time, so whatever distance they are apart had to be crossed at sublight speeds.

But while this would still be very neat, thereâs an even bigger problem: You canât know what youâre sending.

Quantum entanglement means that *observation* of one particle influences the other. Before observing, you donât know what you have. Once you know, itâs already been âsentâ. Hence, data transmitted by quantum entanglement is completely random. Which is great if what you want to share is an encryption key, but rather undesirable when you want to say hi.

**Dolnor**#6

Thank you for clearing that up @jedidia because I was worried that we could soon have Quantum Flame Wars, Quantum Griefing, Quantum Doxing, and everything related to the Internet but in Quantum Quantities! -)

TQQdlesâ˘

**Genesais**#8

If you are interested in the âNo-communication theoremâ this wikipedia page sums it up.

**Virakotxa**#9

The no-communication theorem implies the no-cloning theorem, which states that quantum states cannot be (perfectly) copied. That is, cloning is a sufficient condition for the communication of classical information to occur. To see this, suppose that quantum states could be cloned. Assume parts of a maximally entangled Bell state are distributed to Alice and Bob. Alice could send bits to Bob in the following way: If Alice wishes to transmit a â0â, she measures the spin of her electron in the z direction, collapsing Bobâs state to either {\displaystyle |z+\rangle _{B}} |z+\rangle _{B} or {\displaystyle |z-\rangle _{B}} |z-\rangle _{B}. To transmit â1â, Alice does nothing to her qubit. Bob creates many copies of his electronâs state, and measures the spin of each copy in the z direction. Bob will know that Alice has transmitted a â0â if all his measurements will produce the same result; otherwise, his measurements will have outcomes {\displaystyle |z+\rangle _{B}} |z+\rangle _{B} or {\displaystyle |z-\rangle _{B}} |z-\rangle _{B} with equal probability. This would allow Alice and Bob to communicate classical bits between each other (possibly across space-like separations, violating causality)

Ok, so cloning particles would be neededâŚ Who would have guessed instantaneous quantum communication would be so counterintuitive! Pesky laws of physicsâŚ