Stabiliteet

Stabiliteet refers to the property of a system to maintain or return to a state of balance after disturbances. It describes how resistant a system is to change and how predictably it behaves when subjected to perturbations. The concept is used across disciplines, often with domain-specific definitions and criteria, but sharing the core idea of stability as persistence of equilibrium or bounded response.

In dynamical systems, stability means that small disturbances do not lead to unbounded growth. Lyapunov stability, asymptotic stability, and marginal stability are standard classifications. In control theory, a system is stable if its output remains bounded for bounded input, and margins like gain and phase margins quantify how close the system is to instability. In mechanical engineering, static stability concerns the location of the center of gravity relative to the base, while dynamic stability deals with the system's response to time-varying forces.

In chemistry and materials science, chemical stability refers to resistance to decomposition under given conditions. In ecology and climatology, stability describes the persistence of ecosystems or climate states under disturbance, and resilience is often discussed as a related concept. In economics and social policy, stability denotes lasting prices, inflation, employment, or governance, often pursued through policy frameworks intended to dampen volatility.

Assessment of stabiliteet involves mathematical analysis, simulations, experiments, and historical data. Indicators include damping ratios, eigenvalues, Lyapunov functions, and empirical measures of variance or autocorrelation. The term highlights the importance of predictable behavior in engineering safety, scientific understanding, and policy planning.