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In all of the books that I read, the intermediate steps in turning cryonics into a useful technology seem to be glossed over, and the actual implementation is not described in great detail.

Is there a story or book which contains a good description of what the transition between the current state of the art and technology useable for interstellar travel might look like?

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Suspended animation for space travel would require that the technology inflict little enough damage that the body can repair itself, either with or without the help of the particular era's level of bio/nanotech. There are two technological tracks for this to develop. One is to start experimenting with dead people and steadily refining the process until we can start bringing them back. The ones preserved with the highest level of technology would take the lowest level of repair technology (perhaps none at all), and the lowest tech preservations would take the highest tech to repair.

Conceivably, this leads to a first-in, last-out scenario with some individuals being reanimated right away, and others (such as today's patients perhaps) taking centuries to be brought back. Regardless of how long it takes, the patient arguably has some kind of moral right to survival despite matching a particular era's criteria for legal death. Many cryonicists only worry about repairing the brain, since the other organs can probably be replaced with sufficient biotech (and there are advances in tissue engineering that make this seem very plausible).

Another approach would be to start with hypothermia and hibernation, which are survivable for short periods of time, and slowly work your way to longer and longer periods of time and survival at lower temperatures. This gives empirical evidence at every step, in the form of survival or lack thereof. A form of hibernation that prolongs human life only a few centuries would be a genius invention, as you could most likely use it to survive until true suspended animation, and eventually a comprehensive cure for aging are achieved. Unfortunately, the clinical trials would be so long in duration that it probably would not be a route to the stars for you unless you were a lucky test subject.

Animal models like the wood frog could prove instructive, but if the procedure were to be perfected in humans it would be likely to involve avoiding freezing altogether, a process called vitrification. This is accomplished in cryonics patients by replacing much of the water of the cells with substances that form glass at low temperatures. The challenge is mitigating and reducing the toxicity of these chemicals. The toxicity level is too high for this to be reversible in brains, but there has been success with rabbit kidneys surviving vitrification.

A book that tackles a lot of cryonics issues is "The First Immortal" by James Halperin, though I'm not sure how far it goes into the technical details. Robert Prehoda wrote some interesting stuff about the hibernation route. Wikipedia's entry on cryopreservation, and the science faq on Alcor's website have some good information on the topic. Thomas Donaldson (who is now resting in a dewar) wrote a lot on the distinction between Suspended Animation and Cryonics.

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  • Does the Alcor site go into predictions on how the technology might develop into the distant future? – blueberryfields Feb 1 '11 at 5:28
  • Yes there are some references in the science faq: alcor.org/sciencefaq.htm under "How can imperfect preservation be reversed?" – user594 Feb 1 '11 at 17:26
  • There is also a story by Robert Prehoda about the development of hibernation into a full cryosuspension technology here: cryonet.org/cgi-bin/dsp.cgi?msg=28645 – user594 Feb 2 '11 at 0:24
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There are companies that offer to freeze your body (or just your head) once yo die, in the hope that you can be "reanimated" in the future. As for cryogenics while still alive, there have been people who are found frozen in snow, or in rivers, and were subsequently revived without any damage to their brains, or even any frostbite. It seems that they were usually "frozen" slowly, which allows cells to expand without bursting (since we are made of water, which expands). Some frogs can also burrow into the ground, become frozen during winter, and then thaw during spring. As for hard research, there are labs where rats have been successfully frozen for several hours, and then come back with no damage. but when doing it for days, damage seems to accumulate. Finally, there has been research into doing this for severe accidents (like car crashes), where a slurry of very fine ice is pumped into a persons lungs to put them into a close state of freezing, so that they can be brought to a hospital with less damage on the way.

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  • 1
    Is this a quote from a story? – blueberryfields Jan 29 '11 at 22:39
  • That should be quickly. As Alton Brown likes to point out on his show Good Eats fast freezing leads to small ice crystals, which leads to less damage to the food. Meat is meat. – DampeS8N Jan 29 '11 at 23:55
  • @blueberryfields, what do you mean? – Teknophilia Jan 30 '11 at 0:13
  • I'm looking for a story or book that starts with the current state of the art and ends with interstellar travel. – blueberryfields Jan 30 '11 at 0:35
  • Completely frozen and subsequently revived, in real life? Seriously?? References, please... – vsz Feb 18 '12 at 11:38
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"Cryogenic freezing" would not be relevant to suspended animation through cryopreservation because ice formation is damaging. Non-toxic cryoprotectants or other technologies that prevent freezing at low (cryogenic) temperatures would be necessary. Such technologies are sought by those who practice cryonics. Current cryonics practice is to replace body water with vitrification (anti-freeze) solution. Although ice formation can be eliminated in the brain, ice cannot be eliminated from all body tissues, nor can cryoprotectant toxicity be entirely avoided. Better perfusion and less toxic cryoprotectants must be found.

I have examined the question of the potential for spaceflight in the last section of my essay on Cryopreservation as a means of Suspended Animation.

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The only book I know of, which presents cryogenic freezing in a "hard sci-fi" context, and makes it even an important plot point instead of glossing over it, is Fiasco from Stanisław Lem.

In that novel, cryogenic freezing is a very unreliable and dangerous process, and is only used for emergencies. They build it into the cockpits of giant mechas used for engineering and construction projects in dangerous areas, so that in case of an accident the pilot could use it as a last resort. In that time in-universe, the technology to revive them did not yet exist. The author describes that the real-life (so, in-universe, the past) attempts where rich old people were frozen would not work, as all the brain cells will be damaged so that revival would not be possible.

That emergency cryogenic device is described in a very detailed way, and it's quite gory. To preserve the brain mostly intact, it has to be frozen with liquid nitrogen from all sides as quickly as possible, so tubes crash violently through the face and the jaws, to inject liquid nitrogen, shattering most of the skull in the process (while the victim is still alive and awake). Even many decades later, when the technology for revival exists, it is not an easy task. Most of the victims do not survive at all, and the one they can save (in a very controlled, low-gravity environment), still requires extensive surgery, long recovery time, and suffers from severe memory loss.

If I remember correctly, they call it vitrification, as it does not just freeze the body (crystallization would destroy the cells), but they purge all the blood, and most fluids out of the body.

It is used in interstellar travel in such a way, that one of the passengers on the very first interstellar flight is such a cryogenically frozen body, so that they can attempt to perform the very first revival surgery when they left the Solar System.

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Another huge issue would the energy required to keep someone 'on ice' for an undetermined period of time, as you will need to either constantly keep them at that set temperature that is considered efficient, or a plentiful enough of the chemical exchange (like dialysis) to keep them in chemical stasis. If you were theoretically going to send a ship in which the travel time was greater than resources that one would need to sustain life, the other problem would be who would be piloting the ship. Today's computers would be great for A to B traveling, but maintenance issues and slight course adjustments would be needed. Who can predict what space junk may be encountered, or the various amounts of gravity wells, solor wind shifts, and the ever-present anomolies we can't predict (like black holes) that would need someone to stay away for. You would have to provide generations of pilots who would grow old and die before reaching their destination. And even if cryo did work, there's also the effects of space travel, such as the leeching of calcium in the bones, muscluar degeneration, organ shifting, and gravity sickness. Just because one is frozen doesn't necessarily mean that the enviromental hazards can be necessarily ignored.

IMO, we'd be better off sending unborn clones with sublimital teaching/training, or AI.

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