[New horizons in medicine. Aging and the laws of modern physics]

Even today the problem of aging is not well known. The latest discoveries on the arrow of time, the theory of complexity, the identification of dissipative stationary structures in "non equilibrium", the observation that deterministic systems with a complex structure may produce chaos (which today we have begun to identify, with evident contradictions, laws and principles: the laws of disorder), are the new laws by which it will be possible to understand the evolution along the time of automatic control feed-back of homeostasis and so the progression of senescence. The attention is pointed particularly to three magnitudes of modern physics: dynamic stability, dissipative structures and entropy. In aging the structures of automatic control systems are submitted to a greater functional effort with the results of a reduction of dynamic stability, an increase in dissipative phenomena and entropy. Moreover the functional exhaustion of homeostatic systems (the linearization of the system) is not compatible with life unless a substitute system takes on its function. In this condition the possibility of survival of the living subjects is conditioned to the capacity of the vicarial system of having a higher state of "non equilibrium" at disposal and therefore of a higher dissipative capacity. From the valuation of dynamic stability, dissipative structures and entropy, it appears possible in a near future to clarify many aspects of the nature and dynamics of aging.