Discover how cryonics works, the principles behind it, and what the future may hold for long-term biological preservation. Although it may seem like science fiction, cryonics is grounded in scientific principles and ongoing research.
While cryonics may seem like science fiction, it’s built on well-established scientific principles and an evolving understanding of life, consciousness, and medical possibility.
To truly understand cryonics means looking beyond the headlines and examining the scientific evidence, philosophical foundations, and rational thinking that make this field both credible and compelling for a growing community of forward-thinking individuals.
“I hope you’ll do it [cryonics] the same way I’d hope you’d take a shot with an experimental drug if you were sick and it were the one chance you had. Because it’s worth a try.”
— Tim Urban, Why Cryonics Makes Sense
Together, these pillars form the theoretical foundation for cryonics. They cover the essential elements that make cryonics possible.
Human embryos are routinely cryopreserved for years at ultra-low temperatures. Through IVF and fertility treatments, these embryos later develop into healthy humans. Similarly, there are documented cases of individuals successfully revived after hours without vital signs due to extreme cold exposure. These biological precedents, found throughout the animal kingdom, indicate that life processes can be paused and resumed when biology is properly preserved.
Cryoprotectant solutions allow tissue to be cooled to extremely low temperatures without ice formation. This cooling process is called vitrification, and it enables the preservation of the human body’s vital structures, with a particular focus on the brain.
Future medical advances may enable tissue repair and regeneration down to the cellular and molecular levels. These technologies could make it possible to recover preserved individuals whose basic brain structures remain intact.
The Cryonics Mindset
Cryonics requires thinking beyond the typical human planning horizon of decades to consider possibilities across centuries. This long-term perspective fundamentally changes how you approach decisions – not just about preservation, but about investments, relationships, and life choices. People who choose cryonics often find that extending their time horizon makes them more thoughtful about sustainability, technological progress, and the kind of future they want to help create.
The Cryonics Mindset
Healthy lifestyle choices, medical treatments, and wellness practices can extend lifespan, but they all eventually encounter fundamental biological limits that current science cannot overcome. Cryonics takes a fundamentally different approach: instead of fighting aging in real – time, it preserves you through time until medical technology develops solutions to problems that are currently insurmountable.
The Cryonics Mindset
People respond to mortality in different ways. Some find peace in accepting it as final and focusing on legacy and meaning. Others prefer to explore every available option rather than accept what may not be permanent. Cryonics represents the choice to take action when action is possible, allowing you to make an informed decision about your future rather than simply accepting the default path.
The Cryonics Mindset
Cryonics isn’t just a medical procedure – it’s joining a community of people who think seriously about the future and take action based on evidence rather than tradition. This community includes scientists, engineers, software developers, philosophers, and other forward-thinking individuals. Being part of this network means you’re not alone in making an unconventional but rational choice, and you’re investing in a shared vision of what the future could hold.
You’ve now explored the core foundations that make cryonics both scientifically plausible and rationally defensible. Whether this information confirms existing thoughts or challenges previous assumptions, you’re now part of the informed conversation about life, technology, and human possibility. Welcome to the future.
Alcor’s patients are kept in liquid nitrogen, which is very cold (-196C/-320F). To prevent both the patient and the liquid nitrogen from warming up, they are kept in a giant stainless steel thermos bottle called a Dewar. A vacuum and reflective surface between the inner and outer layers prevent heat from entering. This concept was invented by Sir James Dewar in 1892 and has been used ever since both by campers and scientists to keep hot things hot and cold things cold. No electricity is needed to maintain the temperature.
Once a Dewar is fully loaded with liquid nitrogen it can keep its contents cold for three months or more without any active support. Alcor tops off its Dewars once a week to be extra-conservative.
When the tissue is slowly cooled, ice first forms between cells. The growing ice crystals increase the concentration of solutes in the remaining liquid around them, causing water to be pulled from the cell through a process called osmotic dehydration. If cryoprotectants are present, the freezing point of the unfrozen solution drops sooner and faster, limiting the total amount of ice that forms. As the temperature drops below -40°C, the cryoprotectant concentration becomes so high in the remaining unfrozen solution that ice stops growing. Cells survive suspended in the residual unfrozen liquid between ice crystals. As the temperature drops below about -100°C, this unfrozen solution containing the cells becomes a glassy solid. This is called vitrification.
Alcor maintains its leadership in the field of cryonics by:
In cryonics, cryoprotectant solutions are circulated through the patient’s vascular system near 0 °C over several hours, gradually replacing more than half of the water inside cells with cryoprotectant. Living cells can survive this process when introduction and removal are done at low temperatures.
A cryoprotectant is a small molecule that easily penetrates cells and lowers the freezing point of water. Alcor uses an advanced cryoprotectant called M22.
Molecular nanotechnology is an emerging technology for manufacturing and manipulating matter at the molecular level. The concept was first suggested by Richard Feynman in 1959. The theoretical foundations of molecular nanotechnology were developed by K. Eric Drexler, Ralph Merkle, and others in the 1980s and 1990s. More recently the future medical applications of nanotechnology have been explored in detail by Robert Freitas in his books, Nanomedicine Vol. I (Basic Capabilities) and Nanomedicine Vol. IIA (Biocompatibility). These scientists have concluded that the mid to late 21st century will bring an explosion of amazing capabilities for analyzing and repairing injured cells and tissues, similar to the information processing revolution that is now occurring. These capabilities will include means for repairing and regenerating tissue after almost any injury provided that certain basic information remains intact. A non-technical overview of nanotechnology, including an excellent chapter on cryonics (“biostasis”), is available in Eric Drexler’s book, Engines of Creation.
The lower the temperature, the slower the speed of metabolic processes. At the cryogenic temperatures used by Alcor, essentially all metabolic activity ceases. Without metabolic activity, tissue is not degrading, allowing for decades or centuries in the preserved state.
