NEW VIDEO!
Added 2016-03-15 14:54:24 +0000 UTCA reply to CGP Grey's video about teleportation, consciousness and Star Trek.
Comments
Nice video Henry! In my opinion there is in deed a deep connection between life/death and information structure. It may have tremendous impact on our moral rules, especially once the AI emerges. It's not only about teleportation of the state:)
Marcin Maciejewski
2016-03-16 09:12:33 +0000 UTCAnd as Jesse says, it's very easy to destroy a quantum state and fail at the teleportation (this is also why we don't have large-scale quantum computers yet, either – the quantum state is very sensitive to disturbance and accidental decoherence or "collapse of the wavefunction")
Henry Reich
2016-03-15 19:50:26 +0000 UTCIn the context of quantum teleportation, very much yes. The path from "read" to "write" relies on two distinct channels of information. 1: both teleporters must be filled with at least enough spare matter to account for the amount you wish to teleport prior to anybody stepping in, and the matter in both teleporters must be "entangled" beforehand. Luckily the payload does *not* have to be entangled beforehand, but it will get entangled with the spare matter at this end which in turn also entangles it with the spare matter at the far end as a matter of course. The other channel of information is classical, so our favorite variant of classical information being a "binary encoded digital stream" fits the bill quite nicely. The process is that you entangle the payload with the source transporter's prepared matter, and you measure the results painstakingly and record that as your binary data. You cannot record all data about the goulash that you create on this side thanks to the Heisenberg Uncertainty Principal, but you record as much as you can and that will suffice quite nicely. This "read" operation is necessarily destructive, again thanks to Heisenberg. Now you've got a binary data stream which cannot travel faster than the speed of causality, but a light beam or radio wave — even a radio wave with error correction!! — is still a lot faster than any spacecraft. And you've got destination matter at the destination transporter pad still entangled to the original goulash you made at the source pad (and you've got a hell of a responsibility to protect BOTH source and destination goo from collapsing their entanglement, or entangling new noise that could harm your payload, etc!!) But presuming you can keep the goo at both locations safe, you can send the binary data as early or as late as you'd like.. or you could lose it (and/or ruin the goo) meaning you'd never successfully finish the operation. Once binary data has arrived on destination site, you then use that data as a list of instructions for how to *manipulate* the destination goo (IIRC, it's something like "source goulash at this specific position had property X, so we will coerce destination goo at matching location to also have property X.." and that will render a precise copy of the payload *out of* the destination goop. Do it well enough, and source/destination matter will remain entangled, and ready to transport some more payload! :D Also, it's clear that ideally both the read and the write process would need to complete very, VERY very quickly in order to transport a living thing or else animate processes such as pumping blood down a vessel would experience er.. "complications" if the vessel were taking too long to either appear or disappear in front of the moving blood, and pain receptor nerves have a funny habit of reporting back "woops, part of the nerve is missing!" as quite an acutely uncomfortable experience. x3
Jesse Thompson
2016-03-15 19:47:34 +0000 UTCI imagine being killed by other means would probably be considered a "destructive read"? And yes, in principle the write always happens at a later time because it takes time to send the full information necessary to reconstruct the quantum state at the end point. I didn't mention this in detail, but there are two parts to quantum teleportation – an instantaneous quantum part due to entanglement, and a light-speed-limited classical part where you have to send some information about the "read" operation in order to inform the end-user how to perform the proper "write" operation given the quantum state they've been sent via the entanglement.
Henry Reich
2016-03-15 19:46:04 +0000 UTCSeeing that we cannot have a write without a destructive read, is it possible to have a destructive read without a write, or a write at a later time?
Joe Mako
2016-03-15 18:51:25 +0000 UTC
