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A proposal for a cryogenic grave for cryonics
Followup to: Cryonics wants to be big
We've all wondered about the wisdom of paying money to be cryopreserved, when the current social attitude to cryopreservation is relatively hostile (though improving, it seems). In particular, the probability that either or both of Alcor and CI go bankrupt in the next 100 years is nontrivial (perhaps 50% for "either"?). If this happened, cryopreserved patients may be left to die at room temperature. There is also the possibility that the organizations are closed down by hostile legal action.A
The ideal solution to this problem is a way of keeping bodies cold (colder than -170C, probably) in a grave. Our society already has strong inhibitions against disturbing the dead, which means that a cryonic grave that required no human intervention would be much less vulnerable. Furthermore, such graves could be put in unmarked locations in northern Canada, Scandinavia, Siberia and even Antarctica, where it is highly unlikely people will go, thereby providing further protection.
In the comments to "Cryonics wants to be big", it was suggested that a large enough volume of liquid nitrogen would simply take > 100 years to boil off. Therefore, a cryogenic grave of sufficient size would just be a big tank of LN2 (or some other cryogen) with massive amonuts of insulation.
So, I'll present what I think is the best possible engineering case, and invite LW commenters to correct my mistakes and add suggestions and improvements of their own.
If you have a spherical tank of radius r with insulation of thermal conductivity k and thickness r (so a total radius for insulation and tank of 2r) and a temperature difference of ΔT, the power getting from the outside to the inside is approximately
25 × k × r × ΔT
If the insulation is made much thicker, we get into sharply diminishing returns (asymptotically, we can achieve only another factor of 2). The volume of cryogen that can be stored is approximately 4.2 × r3, and the total amount of heat required to evaporate and heat all of that cryogen is
4.2 × r3 × (volumetric heat of vaporization + gas enthalpy)
The quantity is brackets for Nitrogen and a ΔT of 220 °C is approximately 346,000,000 J m-3. Dividing energy by power gives a boiloff time of
1/12,000 × r2 × k-1 centuries
Setting this equal to 1 century, we get:
r2/k = 12,000.
Now the question is, can we satisfy this constraint without an exorbitant price tag? Can we do better and get 2 or 3 centuries?
"Cryogel" insulation with a k-value of 0.012 is commercially available Meaning that r would have to be at least 12 meters. A full 12-meter radius tank would weigh 6000 tons (!) meaning that some fairly serious mechanical engineering would be needed to support it. I'd like to hear what people think this would cost, and how the cost scales with r.
The best feasible k seems to be fine granules or powder in a vacuum. When the mean free path of a gas increases significantly beyond the characteristic dimension of the space that encloses it, the thermal conductivity drops linearly with pressure. This company quotes 0.0007 W/m-K, though this is at high vacuum. Fine granules of aerogel would probably outperform this in terms of the vacuum required to get down to < 0.001 W/m-K.
Supposing that it is feasible to maintain a good enough vacuum to get to 0.0007 W/m-K, perhaps with aerogel or some other material. Then r is a mere 2.9 meters, and we're looking at a structure that's the size of a large room rather than the size of tower block, and a cryogen weight of a mere 80 tons. Or you could double the radius and have a system that would survive for 400 years, with a size and weight that was still not in the "silly" range.
The option that works without the need for a vacuum is inviting because there's one less thing to go wrong, but I am no expert on how hard it would be to make a system hold a rough vacuum for 100 years, so it is not clear how useful that is.
As a final comment, I disagree that storing all patients in one system is a good idea. Too many eggs in one basket is never good when you're trying to maximize the probability that each patient will survive. That's why I'm keen on finding a system that would be small enough that it would be economical to build one for a few dozen patients, say (cost < 30 million).
So, I invite Less Wrong to comment: is this feasible, and if so how much would it cost, and can you improve on my ideas?
In particular, any commenters with experience in cryogenic engineering would delight me with either refinement or critique of my cryogenic ideas, and delight me even more with cost estimates of these systems. Its also fairly critical to know whether you can hold a 99% vacuum for a century or two.
A: In addition to this, many scenarios where cryonics is useful to the average LW reader are scenarios where technological progress is slow but "eventually" gets to the required level of technology to reanimate you, because if progress is fast you simply won't have time to get old and die before we hit longevity escape velocity. Slow progress in turn correlates with the world experiencing a significant "dip" in the next 50 or so years, such as a very severe recession or a disaster of some kind. These are precisely the scenarios where a combination of economic hardship and hostile public opinion might kill cryonics organizations.
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Comments (137)
With the development of commercial space flight, at some point launching cryonauts into space might become cost-effective.
Right now, with a human head weighting about 5 kg, launching it would cost about $150,000 (not counting the cryopreservation equipment, which is probably significant, and has to withstand the launching stress). Comparing this with a price tag of Alcor full-body preservation, which is also $150,000, it's not totally bonkers to suppose that in a few decades it could become competitive, even without the fancy space elevators.
If it's possible to use the low temperature in space, despite the solar radiation, to keep the temperature down, or somehow keep the package in the shadow, maybe of a specifically crafted accompanying object (I'm not sure about that -- while it's a critical question), it could be a no-maintenance solution, where one would have to perform a deliberate and rather costly procedure to disturb it.
Is the radiation going to cause significant information-theoretic damage? In how long?
Shopping is hard, let's do math!
First, we need a conceptual framework. The whole point of cryonics is to stop chemistry, so if you're cryopreserved and then exposed to ionizing radiation over any period of time, you'll experience the same amount of damage as if you were alive and exposed to that much radiation all at once. (Being alive and exposed to radiation over a period of time is different; you experience less damage because your cells have time to repair themselves.)
Wikipedia says "Estimates are that humans unshielded in interplanetary space would receive annually roughly 400 to 900 milli-Sieverts (mSv) (compared to 2.4 mSv on Earth)". Wikipedia also says that an acute exposure of 4500 to 5000 mSv is "LD50 in humans (from radiation poisoning), with medical treatment". Now, LD50 isn't LD100, but we can agree that it's a Very Bad Dose.
Generously, assuming that the Very Bad Dose is 5000 mSv, and Outer Space's Death Rays are 400 mSv/yr, being Cryopreserved In Space will give you a Very Bad Dose in 12.5 years. This is compared to roughly 2000 years on Earth.
That answers one half of Eliezer's question. My answer to the other half (is this significant in information-theoretic terms) is mu. When you're cryopreserved, you're double dead - dead from whatever killed you, and dead again from cryopreservation damage. You're betting that the future can fix this, but you shouldn't give the future even more work to do, and being triple dead from radiation damage wouldn't help.
This fits in with something I've been wondering in general just for Earth based cryopreservation. How much effort do cryonic organizations make to ensure that there's a minimum of radiation exposure to the cryopreserved individuals? Even background radiation matters a lot more than it would for a living person since there's no ongoing repair mechanisms. I suspect that the bodies are not being subject to much external radiation simply because the cryochambers themselves would block most of it. But, the bodies themselves will generate some radiation, primarily from the decay of potassium 40 and carbon 14. Naively if one were trying absolutely to minimize this one would try to have people who knew they were likely to die soon (due to terminal illness) to eat diets which have less potassium. One could also conceive of having foods made made with carbon that had a low amount of c-14. But given the proportions I'm pretty sure that the bulk of the radiation will be from potassium 40. Robert Ettinger at one point presented a back of the envelope calculation that showed that the radiation just from potassium 40 is unlikely to be a problem if one is the range of 50-100 years, but if one is interested in longer ranges then this becomes a more serious worry.
I'm curious where you are getting the 40% number. I'm not completely sure what we mean by erasing a person since the mind isn't a binary presence that is there or not. Damage can result in loss of some aspects of personality or some memories without complete erasure. Presumably, most people would like to minimize that issue.
Given your 40% claim I tentatively agree with your 10^24 number. There's a minor issue of cascading particles but that shouldn't be a problem since most of the radiation is going to be low energy beta particles. I am however concerned slightly that radiation could result in additional free radicals which are able to jump around and do unpleasant chemical stuff even at the temperatures of liquid nitrogen. I suspect that this would not be a major issue either but I don't think I have anywhere near enough biochem knowledge to make a strong conclusion about this.
Additionally, as STL pointed out, we don't want to make things more difficult for the people reviving them. This combines badly with the first-in-last-out nature of cryonics- the bodies which have been around longer will have more radiation damage and will already be much more technically difficult to revive. Moreover, some people will strongly prefer being reanimated in their own bodies rather than as simulations on computers. The chance that that can occur is lower if the bodies have serious problems due to radiation damage.
Would this be enough to keep thresholds for action potentials correct? I'm more familiar with neural nets for computational purposes than with actual neural architecture, but for neural nets this matters a lot. You can have wildly different behavior even with the same neurons connected to each other just by changing the potential levels. Learning behavior consists not just in constructing or removing connections but also in strengthening and weakening existing connections.
I don't know why you mention the concentrations of neurotransmitters since that's a fairly temporary thing which (as far as I'm aware) doesn't contain much in the way of actual data except about neurons which have fired very recently.
I suspect you are right. Since the important structures involved are significantly larger than one molecule, most of the single molecule alterations will be rather obvious and easy to reverse (for a given kind of 'easy').
Life is tough. Unlife is tougher.
Yes, that would be lots better. The cost of robotics should eventually go down as well, which would enable relatively cheap crater-seeking moon-burrowing robots (though sabotage would become cheaper over time too).
Good idea! A few refinements:
You probably don't want a literally spherical tank; it might roll away and hit something or bother someone. Trading a few % of efficiency for a flattened, ridged bottom might be a good idea.
If you're going to rely on social taboos against disturbing graves, you probably have to keep bodies/tank down to 30, if not an even lower number. A group of family and friends who are buried together in the same crypt are eccentric; a community of essentially unrelated people who are buried together in the same crypt are a cult, and lose a lot of the respect that they would otherwise get from mainstream culture.
Does having a grave with no human/infrastructural maintenance mean that you can't slap a generator on it somewhere? What would having a small solar panel or a petroleum mini-tank do for the chances of repairing minor cracks in the vacuum, or of reducing heat infiltration?
I'm pretty sure this is mistaken-- people generally don't wreck graveyards, even though large numbers of people are buried there.
Right, but the graveyard is thought of as a place where many individuals are separately buried. It's OK, if slightly mischievous, to enter a graveyard, tell spooky stories there, maybe even make out -- but you would never do any of those things inside a grave.
If we build a cryoyard in which there are many individual cryotanks nearby, that will probably be fine, and might cut down on security costs. But if we put all the bodies in the same cryotank, then we run a nontrivial risk of setting off people's creepy cult alarms, and the taboo against disturbing graves-of-people-who-are-not-markedly-unholy may or may not hold.
Yes, and in the very worst case scenario, the weirdness factor would make some teenagers more likely to try to go and vandalize them as a dare. Weird cult having strange frozen crypts is almost asking for that to happen. Unfortunately, this is real life, so we can't even have the satisfaction of this sort of thing triggering the terrible monsters that sleep beneath the cursed ground. (Why yes, I have watched too many bad horror movies. Whatever gave you that impression?)
If you were developing a simulation of a Universe for entertainment purposes, how long would you let the inhabitants think they were at the top level of reality before introducing firm evidence that something was seriously off?
Just curious.
Depends on how long the backstory is.
Also, it's plausible that any species which can simulate complex universes has a longer attention span than we do.
Consider the range of human art. It's plausible that simulators would have at least as wide a range, and I can see purist simulators (watchmaker Gods) and interventionists.
I'd do it over and over again, in all sorts of different ways, record the hilarious results, and after each such session reset the simulation back to an earlier, untampered saved state.
I've long suspected that we live in the original universe's blooper reel.
This doesn't match my intuitions at all, but I'm not an expert on normal people.
Is there any way the plausible range of reactions to big cryonics facilities can be tested?
Let's ask our neighbors!
[grin] I wasn't sure if those were sci-fi or not.
Sure, for starters, but it's hard to say what will and won't be permafrost in 100 years, what with the non-trivial risk of catastrophic climate change and all. If the tank is built right, I think rolling, although unlikely, would still be one of the top 5 most likely failure modes; it is an easy enough flaw to fix.
Even municipal water towers, e.g., aren't perfect spheres, and nobody expects those to fall off their columns and plow through downtown Suburb Beach.
Far from being sci-fi, they are quite common (if we're talking about the same thing): http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#History Common enough that they're the main reason NASA has been targeted by green groups, even.
Cool!
I can verify that these places are accessible, and that the permafrost extends quite a bit farther south than one might expect. I used to live just south of the Yukon territory.
There are regular long-haul trucks that go up there all year round; if you go in winter, you can use an ice road to get to the very cold and remote places. Given the regular volume of traffic, I'd say the cost is not prohibitive. I can get precise figures if you'd like.
Hits on google for "coldest place on earth" seem unanimous that it's somewhere in Antarctica. Here's an interesting newspaper article:
http://www.telegraph.co.uk/news/worldnews/antarctica/6121866/Scientists-identify-coldest-place-on-earth.html
This sounds like it could be a lot of fun.
This place is much colder...
http://gcaptain.com/maritime/blog/wp-content/uploads/2007/07/inside-lng-tank.jpg
If you could only get permission to use it...
Why? Several baskets certainly make sense if you're trying to maximize the probability that at least a few patients survive, and might make sense if you assign significantly negative utility to higher variance in your probability distribution about survival percentage. If you just care about the mean, why would more baskets be better?
It seems to me that, for someone to conceive of their actions as "specifically killing Jack", they have to believe that cryogenics works. If they don't, they're not killing Jack, they're just vandalising his grave, and he was clearly a weirdo. This doesn't necessarily invalidate your points; I'm just saying that you should be careful not to project your own beliefs onto future opposers-of-cryogenics, or you will defend against the wrong attitudes.
I think you're Rokomorphizing an awful lot. You just need to be in a state of mind where smashing a cyro container seems cool, something that can score points with your friends, and where you think you can get away with it.
And in particular, where smashing cryonics facilities will infuriate the people who care about them, even if you don't believe cryonics will work.
I don't have a feeling for whether anti-cryonicism will ever get to that point. My feeling is that the sort of vandalism I'm talking about is extremely impulsive, and just not having cryonic storage near where people live is enough to greatly improve the odds that there won't be random vandalism.
Also guns. People with guns.
You probably mean security guards. Note that decent security is going to add something to the cost of cryonics.
However, this gets to the scarier possibility-- government policies opposed to cryonics. Any ideas about the odds of that happening?
Absolutely, and this conversation has prompted me to consider how best to handle such factors to ensure my head has the maximum chance of survival.
Now that is really scary. Also beyond my ability to create a reliable estimate. I wonder which country is the least likely to have such political problems? Like, the equivalent of the old style swiss banks but for heads.
It's hard to predict that far ahead, though Scandinavia is looking attractive-- the people there don't have a history of atrocious behavior, and there's cold climate available.
The nightmare scenario is a hostile world government, or similar effect of powerful governments-- think about the US exporting the war on drugs.
I hate saying this, but the only protective strategies I can see are aimed at general increase of power-- make money, develop political competence (this can be a community thing, it doesn't mean everyone has to get into politics) and learn how to be convincing to normal people.
This has happened at least once in British Columbia. See this article. As far as I am aware this is at present the only location which specifically singles out cryonics although there are other areas where the regulations for body disposal inadvertently prevent the use of cryonics.
This kind of stuff makes me boil with anger. Some bureacrat busybody inserts garbage about irradiation into a law at the last second, and there's nothing we can do to get it out? Is there some kind of international law against defamation? Because that is exactly what this is. And the stuff they prattle on about it taking advantage of patients in a vulnerable state is total nonsense. What they're doing -- pressuring patients into not cryopreserving -- is taking advantage, and in a particularly grotesque and unconscionable manner.
Ironically, if I were to send them a letter or call them about this stupid law they'd take it as me being a foreign busybody. This is stupid. They're the ones harming BC's global reputation by keeping such idiotic laws on the books.
/rant
According to Mike Darwin one cryonics facility (don't remember which, sorry) has already been shot at from the street.
For being a cryonics facility? Is there enough evidence to determine if it could've been just a random drive-by?
I'm afraid all I know about it is a brief remark from Mike Darwin somewhere in this sequence of videos:
http://www.youtube.com/user/KoanPhilosopher#grid/user/B6A98520CF2F56AC
Putting a big gravestone on top would be a good idea. If the cryo organization fails, it's too easy for all paper and digital records of the grave to be lost. In that scenario, a gravestone will make it more likely that the grave will be rediscovered before the liquid nitrogen boils away.
It'll still be safe from random vandals if it's underground in a remote location, and in the case of anti-cryonics fanatic vandals, there's nothing you can do to keep them from finding out where all the graves are.
Hello, people of the future! Please unfreeze us, and give us warm soup! We'll be very grateful! Thanks much.
Seriously, though, I wonder about the ability of future archeologists to dig through historical Internet information. At the moment, the only attempt to create a thorough historical archive of the Internet is the Wayback machine, and since (I estimate) that the growth of the Internet is accelerating faster than the cheapness of reliable long-term storage, they'll either have to get lots more funding or start being more selective about what they archive.
In terms of the ability to maintain information of interest to future archaeologists through a straight-up global disaster, the Internet isn't any better than paper. Maybe we need to start looking into cuneiform printers...
You could handle this by having each separate cryonic organization exchange data about locations of grave sites. The probability that they will all fail is much lower than any single one failing. Moreover, the most likely situations resulting in such large scale failure will be situations where the human economy is so damaged that replacing the liquid nitrogen will not be feasible.
What do you think about a honeycomb like structure that has individual cells for a single person, but is bundled together enough to get a lot of the insulation benefits of being big?
When you consider the pool of potential patients (over a given century) is in the billions, a few million per location does not necessarily constitute putting all your eggs in one basket. And the process of making it mainstream enough for this to happen could have a huge positive impact the sanity waterline.
With only a few dozen patients, I don't think you will see appreciable economies of scale. The whole idea seems to me reliant on at least a few thousand patients becoming available within a short period of time (or prepaying).
At r=2.9 meters, the size is about in the 10,000 neuro patient range. (V~=102m^3, patients per cubic meter is about 125). You might only fill it part way though if you are aiming for maximum duration, as the less cryogen is displaced the longer the system stays cold. Even so, this could probably hold every cryonicist currently in existence.
Still, filling it to 50% of its volume would only bring down refill time by 50%. And you only can fill to a certain percentage with patients as they are irregularly shaped. I suppose the real question is whether cost or hands-off reliability is the biggest concern.
Not graves!
I think that the idea is good, and the engineering is fine for back-of-the-envelope, but can we please call it a "vault" or something instead of a grave? Cryonics already has an image problem, and we don't want to suggest the people in the grave are permanently dead.
Then we can suggest that they're temporarily dead, but they're still dead, so it's a "grave". Religions have been saying that death is temporary for thousands of years anyways, it wouldn't be anything new.
With liquid nitrogen at -196°C and the average temp in the places you suggest well below freezing (A few minutes of googling suggests it wouldn't be hard to find an average annual temp of -20°C.), I think you could use a more-optimistic ΔT of 175°.
If you care about cryonics and its sustainability during an economic collapse or worse, chemical fixation might be a good alternative. http://en.wikipedia.org/wiki/Chemical_brain_preservation
The main advantage is that it requires no cooling and is cheap. People might be normally buried after the procedure, so it would seem less weird.
However, a good perfusion of the brain with the fixative is hard to achieve.
Chemical fixation could also be combined with those low maintenance cryonic graves just in case the nitrogen boils off.
Australia claims 42% of Antarctica. That should be plenty of room.
Antarctica seems suitable, but why do you suggest that part owned by Australia specifically?
A few months ago, I was thinking about the possibility of cryonic suspension as part of the Australian health-care system. With perhaps 100,000 new people to suspend each year, the AAT seems an obvious place to put them. And once the infrastructure was in place, people from other countries could get involved; it would just be a matter of fashioning the necessary financial and other arrangements.
So perhaps your studies should focus on Antarctic geopolitics, the better to protect our future cryo-bases. Unfortunately, I think the pattern theory of identity (according to which your copy is still you) is an illusion, and that this is all cryonics is likely to provide - a way to make copies of the frozen originals. So I find myself wanting to be supportive of the impulse behind cryonics, but unable to earnestly advocate the creation of national cryosuspension facilities. At best I can just try not to impede such an effort should it arise.
Does it help you at all to think of cryonics as a form of advanced reproduction?
Would you also disagree with the pattern theory of identity as applied to, say, a game of chess?
Imagine I am playing chess on a chessboard with a friend, and then we have to go home, and I copy down the positions of all the pieces and put the board away. The next day, we get out another board, put the pieces into their positions, and start playing from there.
Are we playing the same game of chess?
No, it then becomes a Zombie Chess game.
That's a thought. I must confess I hadn't considered my country to be particularly likely to be a world leader in cryonics adoption.
That belief must be a frustrating belief. Right or wrong I must say my anticipated experience is a whole lot better. But then... I philosophically evaluate preferences over the entire state of the universe by default and yes, 'identity' and affiliation with this form are not something that particularly comes up.
So do I. But the result will be a copy. During sleep and hypothermia, the brain remains in the same physical phase. Cellular metabolism never shuts down, for example. But I would be rather surprised if the "neurophysical correlate of selfhood" survives the freezing transition.
ETA: See followup comment.
When you say you would be surprised, is there any actual observation that could surprise you here?
It's not as though Mitchell's belief is uniquely untestable. It's more like we can't collect any evidence at all about whether identity is preserved, just by reanimating a bunch of people and asking them.
We'd need some sort of neurological description of what "selfhood" means, and then presumably testing to see whether this property is preserved after reanimation would be the actual surprising observation.
Until then, it's irrational to dismiss either theory based purely on the argument that "even if we cryopreserve you, it wouldn't falsify your theory", since this applies to both sides.
No, the position that is unfalsifiable is that there is a distinction here at all.
I don't think so. I'm a processist (though I do think it's unlikely that quantum effects matter), but I can imagine kinds of discoveries that would falsify my current belief on that matter. It could turn out, once we localize and understand consciousness:
...that it's not even "on" or merely suspended all the time, but sometimes is "off" in the normal course of brain operation.
...that it's possible to erase clear memories even with the brain in the same physical state (this would support either Porter's view or some more spiritual dualism).
...that there is more than a single thread of consciousness, and no particular continuity of identity for the person as a whole, even though some thread is operating all the time.
Of those, one and three even seem plausible, but I can't think of a way to do the experiments at our current level of understanding and technology. In any case, once we actually have a working and well-tested theory of consciousness, identity will either vanish or be similarly well-understood.
I suspect you wrong him here - I'm guessing post-freeze Mitchell would say "Obviously I feel like I'm the same person, but now I know I've been cryopreserved I must conclude I'm a copy, not the real thing. I feel good about being alive, but it's copy-Mitchell who feels good, not the guy who got frozen."
So that is why there is such interest in vitrification! grin/duck/run...
A couple thoughts on places to look for ideas, places where people have probably been thinking about similar challenges:
I think GreenRoot refers to the situation where this isn't available, or they wouldn't have to worry about cryogenic preservation.
I understand. I was thinking
..but I'm misjudging relative distances? That is, a spaceship wouldn't spend sufficient time near stars?
Why limit yourself to no maintenance at all in your feasibility speculations? Tending graves is common across cultures. As long as you're spinning a tank of liquid nitrogen as a "grave", why not spin a nitrogen topoff as equivalent to keeping the grass trimmed or bringing fresh flowers?
I see what you mean. It's a matter of what threat you have in mind. I'm thinking mainly of the hostility of a pretty-much intact society to cryonics, and how to take your idea of protecting preserved people by using the notion of "respect for the dead" further, also incorporating the idea of honoring the dead by maintaining shrines/graves, etc.
You're totally right that if there's a global depression or civilizational collapse, then the threat of thawing comes more from inability to maintain rather than unwillingness or opposition.
Maybe it would help to split the post, or maybe organize this discussion, to investigate these ideas separately? It seems that engineering speculation about zero-maintenance cryonics is interesting and useful, and that using the "grave" analogy to make cryonics more acceptable and safe from interference is also interesting, but different issues and constraints arise for each of them.
Could someone design a stainless-steel prayer wheel that doubles as a hand-cranked device for condensing nitrogen from the atmosphere?
"We maintain this mechanism to honor our ancestors, that one day they may be reborn" sounds like the kind of thing some Shinto priestesses could've kept straight for all of recorded history, let alone a few centuries.
My comments in this sub-thread brought out more challenges and queries than I expected. I thought that by now everyone would expect me to periodically say a few things out of line regarding identity, consciousness, and so on, and that only the people I was addressing might respond. I want to reply in a way which provides some context for the answers I'm going to give, but which covers old territory as little as possible. So I would first direct interested parties to my articles here, for the big picture according to me. Those articles are flawed in various ways, but much of what I have to say is there.
Just to review some basics: The problems of consciousness and personal identity are even more severe than is generally acknowledged here. Understanding consciousness, for example, is not just a matter of identifying which part of the brain is the conscious part. From the perspective of physics, any such identification looks like property dualism. Here I want to mention a view due to JanetK, which I never answered, according to which the missing ingredient is "biology": the reason that consciousness looks like a problem from a physical perspective is because one has failed to take into account various biological facts. My reply is that certainly consciousness will not be understood without those facts, but nonetheless, they do nothing to resolve the sort of problems described in my article on consciousness, because they can still be ontologically reduced to elaborate combinations of the same physical basics. Some far more radical ontological novelty will be required if we are going to assemble stuff like "color", "meaning", or "the flow of time" out of what physics gives us.
What we have, in our theories of consciousness, is property dualism that wants to be a monism. We say, here is the physical thing - a brain, or maybe a computer or an upload if we are being futuristic - and that is where the mind-stuff resides, or it is the mind-stuff. But for now, the two sides of the alleged identity are qualitatively distinct. That is why it is really a dualism, but a "property dualism" rather than a "substance dualism". The mind is (some part of) the brain, but the mindlike properties of the mind simply cannot be identified with the physical properties of the brain.
The instinct of people trained in modern science is to collapse the dualism onto the physical side of the equation, because they have been educated to think of reality in those terms. But color, meaning and time are real, so if they are not really present on the physical side of the identity, then a truly monistic solution has to go the other way. The problem now is that it sounds as if we are rejecting the reality of matter. This is why I talked about monads: it is a concept of what is physically elementary which can nonetheless be expanded into something which is actually mindlike in its "interior". It requires a considerable rethink of how the basic degrees of freedom in physics are grouped into things; and it also requires that what we would now call quantum effects are somewhere functionally relevant to conscious cognition, or else this ontological regrouping would make no difference at the level where the problem of consciousness resides. So yes, there are several big inferential leaps there, and a prediction (that there is a quantum neurobiology) for which there is as yet no support. All I can say is that I didn't make those leaps lightly, and that all simpler alternatives appear to be fatally compromised in some way.
One consequence of all this is that I can be a realist about the existence of a conscious self in ways which must sound very retrograde to everyone here who has embraced the brave new ideas of copying, patternist theories of identity, the unreality of time on the physical level, and so on. To my way of thinking, I am a "monad", some subsystem of the brain with many degrees of freedom, which is a genuine ontological unity, and whose state can be directly identified with (and not just associated with) my state in the world as I perceive it subjectively. This is an entity which persists in time, and which interacts with its environment (presumably, simpler monads making up the neighboring subsystems of the brain). If one grants for a moment the possibility of thinking about reality in these terms, clearly it makes these riddles about personal identity a lot simpler. There is a very clear sense in which I am not my copies. At best, they are other monads who start out in the same state. There is no conscious sorites paradox. Whenever you have consciousness, it is because you have a monad big enough to be conscious - it's that simple.
So having set the stage - and apologies to anyone tired of my screeds on these subjects - now we can turn to cryonics. I said to Roko
to which he responded
I posit that, in terms of current physics, the locus of consciousness is some mesoscopic quantum-coherent subsystem of the brain, whose coherence persists even during unconsciousness (which is just a change of its state) but which would not last through the cryonic freezing of the brain. If this persistent biological quantum coherence exists, it will exist because of, and not in spite of, metabolic activity. When that ceases, something must happen to the "monad" (which is just another name for something like "big irreducible tensor factor in the brain's wavefunction") - it comes apart into simpler monads, it sheds degrees of freedom until it becomes just another couple of correlated electrons, I don't have a fixed idea about it. But this is what death is, in the monadic "theory". If the frozen brain is restored to life, and a new conscious condensate (or whatever) forms, that will be a new "big tensor factor", a new "monad", and a new self. That is the idea.
You could accept my proposed metaphysics for the sake of argument and still say, but can't you identify with the successor monad? It will have your memories, and so forth. In other words, this ontology of monadic minds should still allow for something like a copy. I don't really have a fixed opinion about this, largely because how the conscious monad accesses and experiences its memories and identity remains completely untheorized by me. The existence of a monad as a persistent "substance" suggests the possibility that memories in a monad might be somehow internal to it, rather than externally supplied data which pops into its field of consciousness when appropriate. This in turn suggests that a lot of what is written, in futurist speculation about digital minds, transferrable memories, and so forth, would not apply. You might be able to transfer unconscious dispositions but not a certain type of authentic conscious memory; it might be that the only way in which the latter could be induced in a monad would be for it, that particular monad, to "personally" undergo the experience in question. Or, it might really be the case that all forms of memory, knowledge, perception and so forth are externally based and externally induced, so that my recollection of what happened this morning is not ontologically any different from the same "recollection" occurring in a newly created copy which never actually had the experience.
Again, I apologize somewhat for going on at such length with these speculations. But I do think that the philosophies of both mind and matter which are the consensus here - I'm thinking of a sort of blithe computationalism with respect to consciousness, and the splitting multiverse of MWI as a theory of physics - are very likely to be partly or even completely false, and this has to have implications for topics like cryonics, AI, various exotic ethical doctrines based on a future-centric utilitarianism, and so on.
My current leading hypotheses:
There is a long history of diverse speculation by scientists about quantum mechanics and the mind. There was an early phase when biology hardly figured and it was often a type of dualism inspired by Copenhagen-interpretation emphasis on "observers". But these days the emphasis is very much on applying quantum mechanics to specific neuromolecular structures. There are papers about superpositions of molecular conformation, transient quantum coherence in ionic complexes, phonons in filamentary structures, and so on. To me, this work still doesn't look good enough, but it's a necessary transitional step, in which ambitious simple models of elementary quantum biophysics are being proposed. The field certainly needs a regular dose of quantitative skepticism such as Tegmark provided. But entanglement in condensed-matter systems is a very subtle thing. There are many situations in which long-range quantum order forms despite local disorder. Like it or not, you can't debunk the idea of a quantum brain in a few pages because we assuredly have not thought of all the ways in which it might work.
As for the philosophical rationale of the thing, that varies a lot. But since we know that most neural computation is not conscious, I find it remarkably natural to suppose that it's entanglement that makes the difference. Any realistic hypothesis is not going to be fuzzy and just say "the quantum is the answer". It will be more like, special long-lived clathrins found in the porosome complex of astrocytes associated with glutamate-receptor hotspots in neocortical layer V share quantum excitons in a topologically protected way, forming a giant multifractal cluster state which nonlocally regulates glutamatergic excitation in the cortex - etc. And we're just not at that level yet.
What evidence is there that would promote any given quantum-mechanical theory of consciousness to attention?
I mean that sincerely - there ought to be some reason that, say, you have to come up with your monad theory, and I quite frankly don't know of any that would impel me to do so.
How I got here:
Starting point: consciousness is real. This sequence of conscious experiences is part of reality.
Next: The physical world doesn't look like that. (That consciousness is a problem for atomism has been known for more than 2000 years.)
So let us suppose that this is how it feels to be some physical thing "from the inside". Here we face a new problem if we suppose that orthodox computational neuroscience is the whole story. There must then be a mapping from various physical states (e.g. arrangements of elementary particles in space, forming a brain) to the corresponding conscious states. But mappings from physics to causal-functional roles are fuzzy in two ways. We don't have, and don't need, an exact criterion as to whether any particular elementary particle is part of the "thing" whose state we are characterizing functionally. Similarly, we don't have, and don't need, a dividing line in the space of all possible physical configurations providing an exact demarcation between one computational state and another.
All this is just a way of saying that functional and computational properties are not entirely objective from a physical standpoint. There are always borderline cases but we don't really care about not having an exact border, because most of the time the components of a functioning computational device are in physical states which are obviously well in correspondence with the abstract computational states they represent. A device whose components are constantly testing the boundaries of the mapping is a device in danger of deviating from its function.
However, when it comes to consciousness, a fuzzy-but-good-enough mapping like this is not good enough, because consciousness (according to our starting point) is an entirely real and "objective" element of reality. It is what it is "exactly", and therefore its counterpart in physical ontology must also have an exact characterization, both with respect to physical parts and with respect to physical states. A coarse-grained many-to-one mapping which is irresolvably fuzzy at the edges is not an option.
But this is a very hard thing to achieve if we persist in thinking of the physical world as a sort of hurricane of trillions of particles in space, with all that matters cognitively being certain mass movements of particles and things made out of them. Fortunately, as it turns out, quantum mechanics suggests the possibility of a rather different physical ontology, and neuroscience still has plenty of room for quantum effects to be cognitively relevant. Thus one is led to consider quantum ontologies in which there is something which can be the exact physical counterpart of consciousness, and theories of mind in which quantum effects are part of the brain's machinery.
I think you grant excessive reliability to your impressions of consciousness. A philosophical argument along the lines proposed is an awfully weak thread to hang a theory on.
Doesn't it mean that consciousness is epiphenomenon? As all quantum algorithms can be expressed as equivalent classical algorithms, and we can have unconscious computer which is functionally equivalent to human brain.
ETA: I can't see any reason to associate consciousness with some particular kind of physical object/process, as it undermines functional significance of consciousness as high-level coordination, decision making and self-representation system of brain.
No, it would just mean that you can have unconscious simulations of consciousness. Think of it like this. We say that the things in the universe which have causal power are "quantum tensor factors", and consciousness always inhabits a single big tensor factor, but we can simulate it with lots of little ones interacting appropriately. More precisely, consciousness is some sort of structure which is actually present in the big tensor factor, but which is not actually present in any of the small ones. However, its dynamics and interactions can be simulated by the small ones collectively. Also, if you took a small tensor factor and made it individually "big" somehow (evolved it into a big state), it might individually be able to acquire consciousness. But the hypothesis is that consciousness as such is only ever found in one tensor factor, not in sets of them. It's a slightly abstract conception when so many details are lacking, but it should be possible to understand the idea: the world is made of Xs, an individual X can have property Y, a set of Xs cannot, but a set of Xs can imitate the property.
What would really make consciousness epiphenomenal is if we persisted with property dualism, so we have the Xs, their "physical properties", and then their correlated "subjective properties". But the whole point of this exercise is to be able to say that the subjective properties (which we know to exist in ourselves) are the "physical properties" of a "big" X. That way, they can enter directly into cause and effect.
Doesn't this undermine your entire philosophical basis for your argument which rests on the experience of consciousness being real? if your system allows such an unconscious classical simulation then why believe you are one of the actual conscious entities? This seems P-Zombieish.
It's like asking, why do you think you exist, when there are books with fictional characters in them? I don't know exactly what is happening when I confirm by inspection that some reality exists or that I have consciousness. But I don't see any reason to doubt the reality or efficacy of such epistemic processes, just because there should also be unconscious state machines that can mimic their causal structure.
I understand you. Your definition is "real consciousness" is quantum tensor factor that belong to particular class of quantum tensor factors, because we can find them in human brains and
we know that at least one human brain is conscious and
consciousness must be physical entity to participate in causal chain.
All other quantum tensor factors and their sets are not consciousness by definition.
Questions are:
How to define said class without fuzziness, when it is yet not known what is not "real consciousness"? Should we include dolphins' tensor factors, great apes' ones and so on?
Is it always necessary for something to exist as physical entity to participate in causal chain? Does temperature exist as physical entity? Does "thermostatousness" of refrigerator exist as physical entity?
Of course, temperature and "termostatousness" are our high-level description of physical systems, they don't exist in your sense. So, it seems that you see contradiction in subjectively apparent existence of consciousness and apparent nonexistence of physical representation of consciousness as high-level description of brain functions. Don't you see flaw in that contradiction?
Causality for statistical or functional properties mostly reduces to generalizations about the behavior of exact microstates. ("Microstate" means physical state completely specified in its microscopic detail. A purely thermodynamic or macroscopic description is a "macrostate".) The entropy goes up because most microstate trajectories go from the small phase-space volume into the large phase-space volume. Macroscopic objects have persistent traits because most microstate trajectories for those objects stay in the same approximate region of state space.
So the second question is about ontology of macrostate causation. I say it is fundamentally statistical. Cause and effect in elemental form only operates locally in the microstate, between and within fundamental entities, whatever they are. Macrostate tendencies are like theromodynamic laws or Zipf's law, they are really statements about statistics of very large and complex chains of exact microscopic causal relations.
The usual materialist idea of consciousness is that it is also just a macrostate phenomenon and process. But as I explained, the macrostate definition is a little fuzzy, and this runs against the hypothesis that consciousness exists objectively. I will add that because these "monads" or "tensor factors" containing consciousness are necessarily very complex, there should be a sort of internal statistical dynamics. The laws of folk psychology might just be statistical mechanics of exact conscious states. But it is conceptually incoherent to say that consciousness is purely a high-level description if you think it exists objectively; it is the same fallacy as when some Buddhists say "everything only exists in the mind", which then implies that the mind only exists in the mind. A "high-level description" is necessarily something which is partly conceptual in nature, and not wholly objectively independent in its existence, and this means it is partly mind-dependent.
The first question is a question about how a theory like this would develop in detail. I can't say ahead of time. The physical premise is, the world is a web of tensor factors of various sizes, mostly small but a few of them big; and consciousness inhabits one of these big factors which exists during the lifetime of a brain. If a theory fulfilling the premise develops and makes sense, then I think you would expect any big tensor factor in a living organism, and also in any other physical system, to also correspond to some sort of consciousness. In principle, such a physical theory should itself tell you whether these big factors arise dynamically in a particular physical entity, given a specification of the entity.
Does this answer the final remark about contradiction? Each tensor factor exists completely objectively. The individual tensor factor which is complex enough to have consciousness also exists objectively and has its properties objectively, and such properties include all aspects of its subjectivity. The rest of the brain consists of the small tensor factors (which we would normally call uncorrelated or weakly correlated quantum particles), whose dynamics provide unconscious computation to supplement conscious dynamics of the big tensor factor. I think it is a self-consistent ontology in which consciousness exists objectively, fundamentally, and exactly, and I think we need such an ontology because of the paradox of saying otherwise, "the mind only exists in the mind".
This really sounds to me like a perfect fit for Robin's grandparent post. If, say, nonlocality is important, why achieve it through quantum means?
This is meant to be ontological nonlocality and not just causal coordination of activities throughout a spatial region. That is, we would be talking about entities which do not reduce to a sum of spatially localized parts possessing localized (encapsulated) states. An entangled EPR pair is a paradigm example of such ontological nonlocality, if you think the global quantum state is the actual state, because the wavefunction cannot be factorized into a tensor product of quantum states possessed by the individual particles in the pair. You are left with the impression of a single entity which interfaces with the rest of the universe in two places. (There are other, more esoteric indications that reality has ontological nonlocality.)
These complex unities glued together by quantum entanglement are of interest (to me) as a way to obtain physical entities which are complex and yet have objective boundaries; see my comment to RobinZ.
Though I agree that this quantum brain idea is against all evidence, I don't think the evolutionary criticism applies. Not every adaptation has a direct effect on inclusive genetic fitness; some are just side effects of other adaptations.
Well, it might be that maintaining the system rather than restarting it when full consciousness resumes is an easier path to the adaptation, or has some advantage we don't understand.
Of course, if the restarted "copy" would seem externally and internally as a continuation, the natural question is why bother positing such a monad in the first place?
If you want something that flies, the simplest way is for it to have wings that still exist even when it's on the ground. We don't actually know (big understatement there) the relative difficulty of evolving a "persistent quantum mind" versus a "transient quantum mind" versus a "wholly classical mind".
There may also be an anthropic aspect. If consciousness can only exist in a quantum ontological unit (e.g. the irreducible tensor factors I mention here), then you cannot find yourself to be an evolved intelligence based solely on classical computation employing many such entities. Such beings might exist in the universe, but by hypothesis there would be nobody home. This isn't relevant to persistent vs transient, but it's relevant for quantum vs classical.
This is, first of all, an exercise in taking appearances ("phenomenology") seriously. Consciousness comes in intervals with internal continuity, one often comes to waking consciousness out of a dream (suggesting that the same stream of consciousness still existed during sleep, but that with mental and physical relaxation and the dimming of the external senses, it was dominated by fantasy and spontaneous imagery), and one should consider the phenomenon of memory to at least be consistent with the idea that there is persistent existence, not just throughout one interval of waking consciousness, but throughout the whole biological lifetime.
So if you're going to think about yourself as physically actual and as actually persistent, you should think of yourself as existing at least for the duration of the current period of waking consciousness, and you have every reason to think that you are the same "you" who had those experiences in earlier periods that you can remember. The idea that you are flickering in and out of existence during a single day or during a lifetime is somewhat at odds with the phenomenological perspective.
Cryopreservation is far more disruptive than anything which happens during a biological lifetime. Cells full of liquid water freeze over and grow into ice crystals which burst their membranes. Metabolism ceases entirely. Some, maybe even most models of persistent biological quantum coherence have it depending on a metabolically maintained throughput of energy. To survive the freezing transition, it seems like the "bio-qubits" would have to exist in molecular capsules that weren't penetrated as the ice formed.
I must have been, at some point, but a long time ago and don't remember.
Clearly there are situations where extra facts would lead you to conclude that the impression of continuity is an illusion. If you woke up as Sherlock Holmes, remembering your struggle with Moriarty as you fell off a cliff moments before, and were then shown convincingly that Holmes was a fictional character from centuries before, and you were just an artificial person provided with false memories in his image, you would have to conclude that in this case, you had erred somehow in judging reality on the basis of subjective appearances.
It seems unlikely that reliable reconstruction of cryonics patients could occur and yet the problem of consciousness not yet be figured out. Reliable reconstruction would require such a profound knowledge of brain structure and function, that there wouldn't be room for continuing uncertainty about quantum effects in the brain. By then you would know it was there or not there, so regardless of how the revivee felt, the people(?) doing the reviving should already know the answers regarding identity and the nature of personal existence.
(I add the qualification reliable reconstruction, because there might well be a period in which it's possible to experiment with reconstructive protocols while not really knowing what you're doing. Consider the idea of freezing a C. elegans and then simulating it on the basis of micrometer sections. We could just about do this today, except that we would mostly be guessing how to map the preserved ultrastructure to computational elements of a simulation. One would prefer the revival of human beings not to proceed via similar trial and error.)
In the present, the question is whether subjectively continuous but temporally discontinuous experience, such as you report, is evidence for the self only having an intermittent physical existence. Well, the experience is consistent with the idea that you really did cease to exist during those 3 hours, but it is also consistent with the idea that you existed but your time sense shut down along with your usual senses, or that it stagnated in the absence of external and internal input.
Which is to say, decision theory for algorithms, understanding of how an algorithm controls mathematical structures, and how intuitions about the real world and subjective anticipation map to that formal setting.
I don't agree with this claim. One would simply need an understanding of what brain systems are necessary for consciousness and how to restore those systems to a close approximation to pre-existing state (presumably using nanotech). This doesn't take much in the way of actually understanding how those systems function. Once one had well-developed nanotech one could learn this sort of thing simply be trial and error on animals (seeing what was necessary for survival, and what was necessary for training to stay intact) and then move on to progressively larger brained creatures. This doesn't require a deep understanding of intelligence or consciousness, simply an understanding of what parts of the brain are being used and how to restore them.
Mass cryonic suspension does not seem likely to be affordable anytime soon: "As of 2010, only around 200 people have undergone the procedure since it was first proposed in 1962" - http://en.wikipedia.org/wiki/Cryonics
Maybe it just hasn't been marketed properly.