= Critical dimension
{disambiguate=phase transition}
{wiki=Critical_dimension}
In the analysis of a <phase transition>, a critical dimension is a spatial dimension at which the character of fluctuations and critical behavior changes. Below a <lower critical dimension> the relevant ordered phase cannot persist; above an <upper critical dimension> <mean-field critical exponents> apply. This is distinct from the <critical dimension of string theory>, where cancellation of <quantum anomalies> selects a target-spacetime dimension.
Back to article page
