Wildly off base. The key steps are whether on a molecular level, no more than one original person has been mapped to one frozen brain; if this is true, we can expect sufficiently advanced technology generally, and systems described in Drexler’s highly specific Nanosystems book particularly, to be sufficient albeit not necessary (brain scanning might work too). There’s also a lot of clueless objections along lines of “But they won’t just spring back to life when you warm them up” which don’t bear on the key question one way or another. Real debate on this subject is from people who understand the concept of information loss, offering neurological scenarios in which information loss might occur; and real cryonicists try to develop still-better suspension technology in order to avert the remaining probability mass of such scenarios. However, for information loss to actually occur, given current vitrification technology which is actually pretty darned advanced, would require that we have learned a new fact presently unknown to neuroscience; and so scenarios in which present cryonics technology fails are speculative. It’s not a question of “fail to disprove”, it’s a question of what happens if you just extrapolate current knowledge at face value without worrying about whether the conclusion sounds weird. Similarly, you can postulate a social collapse which wipes out the infrastructure for liquid nitrogen production, and a cryonics facility could try to further defend against that scenario by having on-premises cooling powered by solar cells… but if you were actually told the US would collapse in 2028, you would have learned a new fact you did not presently know; it’s not a default assumption.
There’s also a lot of clueless objections along lines of “But they won’t just spring back to life when you warm them up” which don’t bear on the key question one way or another.
This is, of course, not anywhere in anything that kalla724 or I said.
However, for information loss to actually occur, given current vitrification technology which is actually pretty darned advanced, would require that we have learned a new fact presently unknown to neuroscience; and so scenarios in which present cryonics technology fails are speculative.
Thank you, this is a solid claim that current cryonics practice preserves sufficient information (even if we presently have literally no idea how to get it out).
This is, of course, not anywhere in anything that kalla724 or I said.
If you complain about how it would be hard to in-situ repair denatured proteins—instead of talking about how two dissimilar starting synapses would be mapped to the same post-vitrification synapse because after denaturing it’s physically impossible to tell if the starting protein was in conformation X or conformation Y—then you’re complaining about the difficulty of repairing functional damage, i.e., the brain won’t work after you switch it back on, which is completely missing the point.
If neuroscience says conformation X vs. conformation Y makes a large difference to long-term spiking input/output, which current neuroscience holds to be the primary bearer of long-term brain information, and you can show that denaturing maps X and Y to identical end proteins, then the ball has legitimately been hit back into the court of cryonics because although it’s entirely possible that the same information redundantly appears elsewhere and the brain as a whole still identifies as single person and their personality and memories, telling us that cryonics worked would now tell us a new fact of neuroscience we didn’t previously know (e.g. that the long-term behavior of this synapse was reflected in a distinguishable effect on the chemical balance of nearby glial cells or something). But currently, if we find out that cryonics doesn’t work, we must have learned some new fact of neuroscience about informationally important brain information not visible in vesicle densities, synaptic configurations, and other things that current neuroscience says are important and that we can see preserved in vitrified rat brains.
We don’t have current tech for getting info out. There’s solid foreseeable routes in both nanoimaging and nanodevices. If the molecules are in-place with sufficient resolution, sufficiently advanced and foreseeable future imaging tech or nanomanipulation tech should be able to get the info out. Like, Nanosystems level would definitely be sufficient though not necessary, and those are some fairly detailed calculations, estimates, and toy systems being bandied about.
The key steps are whether on a molecular level, no more than one original person has been mapped to one frozen brain
Maybe I’m missing something, but even with cremation, on a molecular level probably no more than one person gets mapped to one specific pile of ash, because it would be a huge coincidence if cremating two different bodies ended up creating two identical piles of ash.
You’re missing something. Any one person gets mapped to a very wide spread of possible piles of ash. These spreads overlap a lot between different people. Any one pile of ash could potentially have been generated by an exponentially vast space of persons.
Wildly off base. The key steps are whether on a molecular level, no more than one original person has been mapped to one frozen brain; if this is true, we can expect sufficiently advanced technology generally, and systems described in Drexler’s highly specific Nanosystems book particularly, to be sufficient albeit not necessary (brain scanning might work too). There’s also a lot of clueless objections along lines of “But they won’t just spring back to life when you warm them up” which don’t bear on the key question one way or another. Real debate on this subject is from people who understand the concept of information loss, offering neurological scenarios in which information loss might occur; and real cryonicists try to develop still-better suspension technology in order to avert the remaining probability mass of such scenarios. However, for information loss to actually occur, given current vitrification technology which is actually pretty darned advanced, would require that we have learned a new fact presently unknown to neuroscience; and so scenarios in which present cryonics technology fails are speculative. It’s not a question of “fail to disprove”, it’s a question of what happens if you just extrapolate current knowledge at face value without worrying about whether the conclusion sounds weird. Similarly, you can postulate a social collapse which wipes out the infrastructure for liquid nitrogen production, and a cryonics facility could try to further defend against that scenario by having on-premises cooling powered by solar cells… but if you were actually told the US would collapse in 2028, you would have learned a new fact you did not presently know; it’s not a default assumption.
This is, of course, not anywhere in anything that kalla724 or I said.
Thank you, this is a solid claim that current cryonics practice preserves sufficient information (even if we presently have literally no idea how to get it out).
If you complain about how it would be hard to in-situ repair denatured proteins—instead of talking about how two dissimilar starting synapses would be mapped to the same post-vitrification synapse because after denaturing it’s physically impossible to tell if the starting protein was in conformation X or conformation Y—then you’re complaining about the difficulty of repairing functional damage, i.e., the brain won’t work after you switch it back on, which is completely missing the point.
If neuroscience says conformation X vs. conformation Y makes a large difference to long-term spiking input/output, which current neuroscience holds to be the primary bearer of long-term brain information, and you can show that denaturing maps X and Y to identical end proteins, then the ball has legitimately been hit back into the court of cryonics because although it’s entirely possible that the same information redundantly appears elsewhere and the brain as a whole still identifies as single person and their personality and memories, telling us that cryonics worked would now tell us a new fact of neuroscience we didn’t previously know (e.g. that the long-term behavior of this synapse was reflected in a distinguishable effect on the chemical balance of nearby glial cells or something). But currently, if we find out that cryonics doesn’t work, we must have learned some new fact of neuroscience about informationally important brain information not visible in vesicle densities, synaptic configurations, and other things that current neuroscience says are important and that we can see preserved in vitrified rat brains.
We don’t have current tech for getting info out. There’s solid foreseeable routes in both nanoimaging and nanodevices. If the molecules are in-place with sufficient resolution, sufficiently advanced and foreseeable future imaging tech or nanomanipulation tech should be able to get the info out. Like, Nanosystems level would definitely be sufficient though not necessary, and those are some fairly detailed calculations, estimates, and toy systems being bandied about.
Maybe I’m missing something, but even with cremation, on a molecular level probably no more than one person gets mapped to one specific pile of ash, because it would be a huge coincidence if cremating two different bodies ended up creating two identical piles of ash.
You’re missing something. Any one person gets mapped to a very wide spread of possible piles of ash. These spreads overlap a lot between different people. Any one pile of ash could potentially have been generated by an exponentially vast space of persons.