The idea of cryopreservation is simple and beautiful: When a person is beyond saving by modern methods, we can give them another lifeline. First, perfuse their bloodstream with antifreeze. Once administered, it’s possible to safely cool the body to incredibly low temperatures without ice forming inside organs and crushing delicate cells. Cold slows chemical reactions, all of them: According to the Arrhenius equation, every 10 °C decrease in temperature halves chemical reaction rates. A coolant like liquid nitrogen halves the ordinary rate of chemical reactions 22 times over. That stretches a single second of life into 48 days.

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As you might expect, this simple idea turns out to be monstrously complicated and exacting in practice. The human body is much more finicky than the field’s founders in the 1960s had hoped. But the techniques exist. I’ve spent my life helping to develop them. The cryopreservation available today is far removed from the ideal — fussier, less elegant, and limited in what it can offer. There is much room for improvement and much work to be done. Still, it works, at least for a particular definition of working. We can’t yet warm up a frozen person and revive them, and it’s not certain we ever will. What we can do is reliably preserve memory in an information-theoretic sense. If our current understanding of neuroscience is correct, then we have the techniques to preserve all the information that makes a person who they are — albeit in a form that's impossible to extract with today's technology...

It's terrifying to think that due to the economics of this - ie controlled death, technical work done by specialists, decades of energy-stable cryopreservation -, it's mostly our present-day oligarchs who will be preserved and eventually immortalized.