Our civilization has achieved enormous advances in science and technology, which have made our lives safer, longer and more healthy. The average lifetime has more than doubled in the last 100 years. In many instances, people that suffer severe injury or disease can be cured, and their lives prolonged to a great degree. To extend life beyond the current boundaries and to overcome death has been a central tenet of human striving for millennia, and it forms the core of most of the world’s religions. In short: the pursuit of a long life is a common and natural desire.
Cryonics is a radical approach for attaining this goal. In effect, it is a highly experimental procedure of intensive care, which prevents the decay of the body and thus irrevocable death at a biochemical level. While no guarantee can be given that revival of patients in cryonics storage may one day be possible, there is good scientific evidence that patients can today be preserved with high biological integrity and may be restored to health based on future advances of medicine and technology.
Special focus is placed on the brain, which is the seat of a person’s self, of their memories, personality and their consciousness. Therefore, it is of highest importance in cryonics to conserve the brain and its structure as well as possible. A fast external cooling of the body after the cessation of heart beat is essential. Afterwards, the blood is exchanged by a cryoprotective solution (usually VM1 or M22). This solution prevents ice crystal formation inside the body and the cells during further cooling below 0°C. Instead a glass-like state is formed, in a process called vitrification. The cooling is then continued down to -196°C, the temperature of liquid nitrogen, and the body is stored in a tank filled with liquid nitrogen afterwards. In this way, time is essentially stopped and safe storage is possible over many years or even centuries if necessary.
As advanced technical and medical technologies are developed in the future, it may be possible to rewarm the patient, heal any damage (from disease, age and the side effects of cryopreservation), and restore them to full and healthy life. Thus, cryonics can be understood as medical time travel, whereby a sick person is transported to the future, until such a time when medicine is able to heal and repair them fully.