Superluminal communication
Posted: Sat Jan 04, 2025 11:23 am
https://www.futuretimeline.net/blog/202 ... -cable.htm
To clarify this paragraph:
"Only limited by the speed of light, quantum teleportation could revolutionise communication networks, enabling near-instantaneous transfer of information across vast distances. [..] It could also enable a new, absolutely secure way to share information, wherein direct transmission between distant network users is no longer necessary.":
While the quantum state of the entangled particle is teleported, instantaneously, and can be used to detect eavesdropping, this bit is random as I understand, and any useful information must still travel at or under the speed of light — through a classical channel, some of which today are already near the speed of light. (Most have equipment hops that delay by many milliseconds, as well as light travel through non-vacuum that slows it down; these could be improved).
So "instantaneous transfer" across the solar system, say, will not happen in the future, (at least via quantum teleportation; maybe something else like wormholes will make it possible), and "direct transmission" is still necessary since information cannot be teleported, needing to be transported through classical channels to complete the quantum teleportation.
https://en.m.wikipedia.org/wiki/No-comm ... on_theorem
From https://en.m.wikipedia.org/wiki/Quantum_teleportation:
"Thus, an observation resulting from a measurement choice made at one point in spacetime seems to instantaneously affect outcomes in another region, even though light hasn't yet had time to travel the distance, a conclusion seemingly at odds with special relativity. This is known as the EPR paradox. However, such correlations can never be used to transmit any information faster than the speed of light, a statement encapsulated in the no-communication theorem. Thus, teleportation as a whole can never be superluminal, as a qubit cannot be reconstructed until the accompanying classical information arrives."
Teleportation of macro-scale objects is also theoretically possible, and will very probably occur, as this timeline and many physics experts predict. The teleportation will, however, always be limited by the speed of causality/light.
String theorist Michio Kaku on future teleportation, in an entertaining 3-minute interview.
To clarify this paragraph:
"Only limited by the speed of light, quantum teleportation could revolutionise communication networks, enabling near-instantaneous transfer of information across vast distances. [..] It could also enable a new, absolutely secure way to share information, wherein direct transmission between distant network users is no longer necessary.":
While the quantum state of the entangled particle is teleported, instantaneously, and can be used to detect eavesdropping, this bit is random as I understand, and any useful information must still travel at or under the speed of light — through a classical channel, some of which today are already near the speed of light. (Most have equipment hops that delay by many milliseconds, as well as light travel through non-vacuum that slows it down; these could be improved).
So "instantaneous transfer" across the solar system, say, will not happen in the future, (at least via quantum teleportation; maybe something else like wormholes will make it possible), and "direct transmission" is still necessary since information cannot be teleported, needing to be transported through classical channels to complete the quantum teleportation.
https://en.m.wikipedia.org/wiki/No-comm ... on_theorem
From https://en.m.wikipedia.org/wiki/Quantum_teleportation:
"Thus, an observation resulting from a measurement choice made at one point in spacetime seems to instantaneously affect outcomes in another region, even though light hasn't yet had time to travel the distance, a conclusion seemingly at odds with special relativity. This is known as the EPR paradox. However, such correlations can never be used to transmit any information faster than the speed of light, a statement encapsulated in the no-communication theorem. Thus, teleportation as a whole can never be superluminal, as a qubit cannot be reconstructed until the accompanying classical information arrives."
Teleportation of macro-scale objects is also theoretically possible, and will very probably occur, as this timeline and many physics experts predict. The teleportation will, however, always be limited by the speed of causality/light.
String theorist Michio Kaku on future teleportation, in an entertaining 3-minute interview.