There is growing interest in scientific explanations of aging and in the search for a general theory that can explain what aging is and why and how it happens. There is also a need for a general theoretical framework that would allow researchers to handle an enormous amount of diverse observations related to aging phenomena. Theoretical analysis of systems failure in aging leads naturally to apply the already existing general theory of systems failure, which is also known as the reliability theory. This lecture reviews existing theoretical reliability models and approaches, which help to understand the mechanisms and age-dynamics of systems failure. Empirical observations on systems failure in aging are also reviewed (the Gompertz and Weibull mortality laws, the compensation law of mortality, and the late-life mortality levelling-off), and are theoretically explained through the observed decline in system's redundancy with age. It is shown that redundancy is a key notion for understanding aging, and the systemic nature of aging in particular. Living organisms seem to be formed with a high load of initial damage, and therefore their life span and aging patterns may be sensitive to early-life conditions that determine this initial damage load during early development. Aging is a complex phenomenon, and a holistic approach using reliability theory may help analyze, understand, and, perhaps, control it.
Gavrilov LA, Gavrilova NS. Models of Systems Failure in Aging. In: P Michael Conn (Editor): Handbook of Models for Human Aging, Burlington, MA : Elsevier Academic Press, 2006. 45-68. ISBN 0123693918.
Full text available at: http://longevity-science.org/Failure-Models-2006.pdf