A phase transition is the transformation of a system from one global phase or state to another, for example from an ordered to a disordered phase. The term is most commonly used to describe transitions in thermodynamics between solid, liquid and gaseous states of matter. In Graph Theory, the term phase transition is used in the sense of Bifurcation: an abrupt change in a system's properties depending on the number of edges. In general it describes if a fundamental change in the global emergent properties of a system. Phase transitions also occur in cellular automata, ising models, and membranes.
- Wikipedia entry for Phase transition
- MathWorld entry for Phase transition