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Comment by Eliezer | Hacker News Reader

The startup is not claiming to have current uploading technology. The startup is researching (does not claim to have) brain preservation techniques leading to long-term structure preservation in hopes of uploading sometime in the indefinite future. If your personal opinion is that this cannot happen, that does not make other people who have different beliefs and are upfront about their arguments for them "scammers".

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It is likely an iteration on cadaver plastination, wherein tissues are infused with plastic to preserve their structure. This is what enables those "Bodies" exhibitions that show actual human cadavers that have been plastinated, posed, and dissected to show anatomical details.

If you preserve the structure of the brain well enough, you can scrape it down in micrometer-thick layers and progressively photograph the visible surfaces in sufficient detail to reconstruct a map of all neural connections. Combine this with a working model of a neuron, a physics model for chemical diffusion, and knowledge of how living neurons respond to certain chemicals typically found in the brain or those that can cross the blood-brain barrier, and you can simulate a human consciousness inside a computer.

It won't be you, but it will think it was you. That's almost the same thing as what happens every time you wake up in the morning.

Also, in order to avoid frequently resetting the simulation due to insanity, you probably also need a virtual world that simulates realistic inputs through the sensory nerves.

The technology is plausible, particularly if you are a Kurzweilian or transhumanist. Some may feel more comfortable with "Ship of Theseus"-style gradual migration of an organic brain into digital computer via implantation of technology devices with neuron-computer interfaces. But since we aren't as close to that, injecting your dead brain with epoxy is the closest you can get now to not being dead and gone forevermore.

Note that the necessary knowledge for digitizing a preserved brain is likely centuries away, but that doesn't matter if you can preserve your brain to remain unchanged for centuries. To the new entity that can remember being you and likes all the same things you like, it will be like waking up in the future. And hopefully, you left some money for AI civil rights in your will, so it won't be a digitized slave toiling away on the pattern recognition plantations.

The process is described in the science paper at https://www.sciencedirect.com/science/article/pii/S001122401..., and also at the Brain Preservation Foundation website (http://www.brainpreservation.org/). It involves fixation with glutaraldehyde and then vitrifixation for long-term storage. It does not use plastic.

The casual explanation is that the brains are infused with a chemical that prevents formation of ice crystals and chilled to freezing temperatures until the water in the brain solidifies into a glasslike solid.

This is how frogs in shallow pond-bottoms can freeze solid during the winter and then thaw out in spring. The formation of ice crystals is what damages the organ. But glutaraldehyde is highly cytotoxic, and the brain cells are killed, along with anything else, so your brain won't ever be thawed. They will use ion beams to shave off very thin layers of your brain and use a scanning electron microscope to image it, all while still frozen.

This is the same process, in finer detail, that occurs for detail 3-d imagery of plastinated organs and entire organisms. The crosslinking and heat generated during the curing process of most epoxy resins will destroy the finer structures in the brain as it preserves the macro-structure, so no, you couldn't use the same types of plastic typically used to preserve anatomy specimens. Instead of a microtome, the top layer is ablated with ion beams. Instead of an optical microscope, an electron microscope is used.

You can't currently get a more detailed 3-d image than this. The ion beam can strip away one layer of atoms at a time, and the electron microscope can identify the positions of all the atoms in the next layer.

But imagine the size of that data set. Imaging a volume of about 1500 mL, at a detail level of 1 nm, is 1.5e24 voxels. Even at one bit per voxel, for filled/empty, that's in the yottabyte range. A trillion 1 terabyte hard drives. The gap junction of an electrical synapse is about 3.5 nm, and chemical synapses are 20-40 nm apart. so if you image at a resolution of 3.5nm, you're still talking at least a zettabyte, but at least that's just under half the maximum file size of UFS, at around 2^75 bits.

Better hope those cryo-coolers don't fail before we can store that much data and reduce it all to a neuro-map.

It seems likely you'd have to process as you go, and not store it all. Or have one hell of a datacenter/buffer like the LHC does, holding it until it can be crunched down to a "simple" network instead of voxel data.

There's no real evidence that the human brain functions anything like an Information Processor and, in fact, a growing body of evidence that suggests it's not. We still know so little about the brain and comparing a brain to a computer is is at best a flawed metaphor and at worst an outright falsehood. The idea that any sort of human consciousness can be uploaded or stored by a computer is asinine

The brain is implemented by physics and physics can be simulated by a computer, so I'm not sure I follow you here.

The operative word here being "simulate." I will admit however that that opens a debate about the nature of consciousness in which I'm not prepared to resolutely say would not count as true consciousness.

So I will reframe and clarify my argument -- I believe that we do not know enough about the brain and the nature on consciousness to be able to conclude that taking this kind of "snapshot" of the brain will in anyway preserve any of the necessary information needed to reproduce or even accurately simulate consciousness, and that the argument that it is or will is based on the flawed assumption that the brain is or functions like a information processor (a flawed metaphor that is very quickly reaching it's limitations).

You didn't clarify an argument, you simply made baseless assertions while claiming we don't know enough to make extrapolative arguments.

Literally everything that humans understand is understood in a framework of information processing. It is probably not even possible to understand something without being able to model it as an information-handling process. What basis do you have to say consciousness is different? Because we haven't figured it out yet? It's 2018. There are billions of years of thinking that have yet to happen on the subject.

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