Matter can form durable organisations when its degrees of freedom are constrained by interactions and fed by flows. Living systems push this capacity further thanks to processes that maintain, repair and reproduce their organisation.
An organism maintains itself by exchanging matter and energy with its environment. Its form is not enough to define it, since the components that constitute it are renewed and the regulations that sustain it remain active. Life corresponds to a dynamic organisation whose continuity depends on those processes.
Time in living systems
The proper time of relativity and lived time belong to different domains. The first has a precise physical definition. The second depends on perceptual, cognitive and affective processes. Bringing them together can illuminate the plurality of temporalities without establishing an identity between a relativistic dilation and a modification of subjective experience.
In an organism, biological rhythms, energy availability and physiological state modify the capacities for action. In human beings, stress, attention or exhaustion also influence the perception of duration. A reduction of margins can give the impression that every constraint arrives too fast, but that experience is not a variation of physical time.
Why living systems can hold far from equilibrium
A living system remains far from thermodynamic equilibrium because it stays open. It draws resources, transforms energy and releases heat as well as the products of its metabolism. The environment provides the conditions of that activity without automatically ensuring its internal regulation.
Exchanges of energy and matter are indispensable to biological maintenance. Information intervenes through the structures and signals that orient the organism's reactions. A durable interruption of those flows alters the functions, and then the organisation itself.
Temperature, resources, other organisms and the protections offered by a habitat modify the effort required for maintenance. A favourable environment widens the margins. A degraded or highly variable milieu, by contrast, imposes additional expenditure and can exceed the capacities for adaptation.
In a family or an institution, some functions are sometimes maintained by a person, a routine or a resource that compensates for the failures of the rest. This comparison with living systems remains analogical. It nevertheless makes it possible to spot a critical dependency when continuity rests almost entirely on a single support.
Living systems exploit gradients, that is, differences of concentration, temperature or chemical potential. Those gradients make transformations and transport possible. Maintaining them itself requires exchanges and regulations.
Where it tips
A rupture becomes probable when needs durably exceed resources, when regulations no longer correct the deviations, or when an essential support disappears. The system can maintain its appearance for a time by consuming its reserves. Degradation accelerates once those margins are exhausted.
In summary
Living systems maintain an organisation far from equilibrium thanks to continuous flows, gradients and mechanisms of regulation. They constitute no exception to thermodynamics. Their viability depends on precise relations with the milieu, on sufficient reserves and on a capacity to correct perturbations before margins are exhausted.