Basically, physics says that nothing, not even information can actually travel faster than the speed of light. It’s a universal limit that shows up when you do the math on relativity. This concept is called “causality”.
Because of this, FTL communication is probably impossible. Quantum entanglement seems like it could provide a loophole, but it doesn’t actually work that way. To actually use quantum entanglement for communication, it actually needs a confirmation message, which would have to be delivered by a different means (every quantum message needs a non-quantum confirmation). That confirmation would be bound by the speed of light, thus preserving causality.
This is a very very rough description based on my memory, so some details may be a little off, but it should cover the gist. This article goes into more detail:
Edit: After reading, the answer is more that attempting to impart information onto the entangled particles to send a message necessarily breaks the entanglement and thus does not transmit the information to the other side. Entangling the particles makes their states related to each other, but only at the time of entanglement, and anything that changes either particle (including measuring it) will break the entanglement going forward.
Yup. You just summed up the start of the conversation I had with ChatGPT to figure out exactly what we were talking about Here and why the fact that even if we can’t directly send coherent information, if it appears that a change in particle A directly causes a change in particle B, and it appears that that causation happened Instantaneously, we can’t ever prove it or measure it or know it for certain, because the proving measuring and knowing would have to have occurred at instantaneously themselves in order to actually be proof at all. The even more fascinating part I wound up with is discovering the Holographic Principle, as discovered by Beckenstein and later expanded on and proven by Stephen Hawking, that says that all information in the 3-D world is actually encoded into a 2-D framework. That one blew my mind and I’m gonna be thinking about that for a while.
The holographic principle is fascinating, though a quick nitpick: I’m pretty sure we’ve only proven it for contracting spacetimes (as opposed to our expanding one), but a lot of people imagine it does apply to ours as well (I certainly suspect it does)
Basically, physics says that nothing, not even information can actually travel faster than the speed of light. It’s a universal limit that shows up when you do the math on relativity. This concept is called “causality”.
Because of this, FTL communication is probably impossible. Quantum entanglement seems like it could provide a loophole, but it doesn’t actually work that way. To actually use quantum entanglement for communication, it actually needs a confirmation message, which would have to be delivered by a different means (every quantum message needs a non-quantum confirmation). That confirmation would be bound by the speed of light, thus preserving causality.
This is a very very rough description based on my memory, so some details may be a little off, but it should cover the gist. This article goes into more detail:
https://bigthink.com/starts-with-a-bang/quantum-entanglement-faster-than-light/
Edit: After reading, the answer is more that attempting to impart information onto the entangled particles to send a message necessarily breaks the entanglement and thus does not transmit the information to the other side. Entangling the particles makes their states related to each other, but only at the time of entanglement, and anything that changes either particle (including measuring it) will break the entanglement going forward.
Yup. You just summed up the start of the conversation I had with ChatGPT to figure out exactly what we were talking about Here and why the fact that even if we can’t directly send coherent information, if it appears that a change in particle A directly causes a change in particle B, and it appears that that causation happened Instantaneously, we can’t ever prove it or measure it or know it for certain, because the proving measuring and knowing would have to have occurred at instantaneously themselves in order to actually be proof at all. The even more fascinating part I wound up with is discovering the Holographic Principle, as discovered by Beckenstein and later expanded on and proven by Stephen Hawking, that says that all information in the 3-D world is actually encoded into a 2-D framework. That one blew my mind and I’m gonna be thinking about that for a while.
The holographic principle is fascinating, though a quick nitpick: I’m pretty sure we’ve only proven it for contracting spacetimes (as opposed to our expanding one), but a lot of people imagine it does apply to ours as well (I certainly suspect it does)
I followed this branch of the rabbit hole. Goddamn you for bringing another contradiction into play in my brain!