List of types of equilibrium

This is a list of various types of equilibrium, the condition of a system in which all competing influences are balanced.

Biology

Equilibrioception, the sense of a balance present in human beings and animals
Equilibrium unfolding, the process of unfolding a protein or RNA molecule by gradually changing its environment
Genetic equilibrium, theoretical state in which a population is not evolving
Homeostasis, the ability of an open system, especially living organisms, to regulate its internal environment
Punctuated equilibrium, theory in evolutionary biology
Sedimentation equilibrium, analytical ultracentrifugation method for measuring protein molecular masses in solution
Equilibrium Theory (Island biogeography), MacArthur-Wilson theory explaining biodiversity character of ecological islands

Equilibrant Force, which keeps any object motionless and acts on virtually every object in the world that is not moving
Equilibrium figures of Earth and planets (physical geodesy)
Equilibrium mode distribution, the state of fiber optic or waveguide transmission in which the propagation mode does not vary with distance along the fiber or changes in the launch mode
Hydrostatic equilibrium, the state of a system in which compression due to gravity is balanced by a pressure gradient force
Hyperbolic equilibrium point, a mathematical concept in physics
Mechanical equilibrium, the state in which the sum of the forces, and torque, on each particle of the system is zero
Radiative equilibrium, the state where the energy radiated is balanced by the energy absorbed
Secular equilibrium, a state of radioactive elements in which the production rate of a daughter nucleus is balanced by its own decay rate

Thermodynamic equilibrium, the state of a thermodynamic system which is in thermal, mechanical, and chemical equilibrium (see below). When it is said that a system is simply "in equilibrium", this is often what is meant.
Chemical equilibrium, the state in which the concentrations of the reactants and products have stopped changing in time.
Diffusive equilibrium, when the concentrations of each type of particle have stopped changing.
Thermal equilibrium, a state where an object and its surroundings cease to exchange energy in the form of heat, i.e. they are at the same temperature.**
Donnan equilibrium, the distribution of ion species between two ionic solutions separated by a semipermeable membrane or boundary
Dynamic equilibrium, the state in which two reversible processes occur at the same rate
Equilibrium constant, a quantity characterizing a chemical equilibrium in a chemical reaction
Partition equilibrium, a type of chromatography that is typically used in GC
Quasistatic equilibrium, the quasi-balanced state of a thermodynamic system near to equilibrium in some sense or degree
Schlenk equilibrium, a chemical equilibrium named after its discoverer Wilhelm Schlenk taking place in solutions of Grignard reagents
Solubility equilibrium, any chemical equilibrium between solid and dissolved states of a compound at saturation
Vapor–liquid equilibrium, where the rates of condensation and vapourization of a material are equal

Competitive equilibrium, economic equilibrium when all buyers and sellers are small relative to the market
Economic equilibrium, a condition in economics
Equilibrium price, the price at which quantity supplied equals quantity demanded
General equilibrium theory, a branch of theoretical microeconomics
Intertemporal equilibrium, an equilibrium concept over time
Lindahl equilibrium, a method proposed by Erik Lindahl for financing public goods
Partial equilibrium, the equilibrium price and quantity which come from the cross of supply and demand in a competitive market.
Radner equilibrium, an economic concept defined by economist Roy Radner in the context of general equilibrium
Recursive competitive equilibrium, an economic equilibrium concept associated with a dynamic program
Static equilibrium (economics), the intersection of supply and demand in any market
Sunspot equilibrium, an economic equilibrium in which non-fundamental factors affect prices or quantities
Underemployment equilibrium, a situation in Keynesian economics with a persistent shortfall relative to full employment and potential output

Correlated equilibrium, a solution concept in game theory that is more general than the well-known Nash equilibrium
Nash equilibrium, a solution concept in game theory involving two or more players
- Quasi-perfect equilibrium, a refinement of Nash Equilibrium for extensive form games due to Eric van Damme
- Sequential equilibrium, a refinement of Nash Equilibrium for extensive form games due to David M. Kreps and Robert Wilson
Symmetric equilibrium, in game theory, an equilibrium where all players use the same strategy
Trembling hand perfect equilibrium assumes that the players, through a "slip of the hand" or tremble, may choose unintended strategies
- Proper equilibrium due to Roger B. Myerson, where costly trembles are made with smaller probabilities

Social equilibrium, a system in which there is a dynamic working balance among its interdependent parts
Equilibrium moisture content, the moisture content at which the wood is neither gaining nor losing moisture
Equilibrium point, node in mathematics
Reflective equilibrium, the state of balance or coherence among a set of beliefs arrived at by a process of deliberative mutual adjustment