Looking for a cryonics-laden brain workout? Check out the Q2 2020 issue of Cryonics. The single weightiest piece in this issue is “Mathematics and Modeling in Cryonics: Some Historical Highlights” by R. Michael Perry and Aschwin de Wolf. If you find yourself arguing with a critic who says cryonics is based on wishful thinking and not analysis, shove this article at them. As the authors show, mathematics and modeling have been used in cryonics since the very early days. Even back in the early 1970s, Art Quaife used mathematical analysis to model early perfusion systems and then followed up with a 1985 paper examining heat flow in the cryopreservation of humans.

I remember reading a fascinating article by biochemist Hugh Hixon, a long-time Alcor staff member, back in 1988 titled “How Cold is Cold Enough?”. The authors explain that Hixon chose the fastest known biological reaction, catalase and then compared reaction rates as the temperature is lowered from body temperature (37°C) on down. Chemical reactions that happen in one second at body temperature would take about 25 million years at the temperature of liquid nitrogen. Hixon addressed the question of how cold you need to go to not have to worry any further. In reality, below about -135°C, biochemical reactions would slow down far more than his methods suggested because “translational molecular motion is inhibited so safe storage of almost indefinite length should be possible”.

I also found engaging other pieces analyzing the effects of time and chemistry on the quality of cryopreservation. Several people have pondered the question of what cooling rate would be needed to escape ischemic injury. Authors Perry and de Wolf have both delved into the question, and Steve Harris developed a possible indicator in his E-HIT (equivalent homeothermic ischemic time) measure. We use a version of that measure in Alcor’s operating room to tell us when to cease cardiopulmonary support and begin surgery. This measure substitutes cooling rate for a fixed temperature.

There’s plenty more fascinating work examined here. (Really. You don’t have to be a mathematician to be fascinated, I promise.) For instance, cryobiologists Gregory Fahy, Brian Wowk and others at 21st Century Medicine (21CM) uncovered a method of predicting the toxicity of cryoprotective solutions to a fair accuracy based on their molecular constituents, and Perry used his mathematical mind to predict future cryonics caseloads.

If that doesn’t satisfy you, you will find more computational work related to cryonics in scholar profile and Q&A with Roman Bauer, followed by his article “Computational Neuroscience and Cryonics: Strangers that are Just Friends Waiting to Happen”. For a change of pace, I especially enjoyed David Brand-Erichsen’s critical review of the 1988 Star Trek: The Next Generation episode, “The Neutral Zone”. David echoes my own reactions to an episode that somehow both shows cryonics working while mindlessly repeating the “we need death” rationalization.