biocomplexity criticalpoint dynamics equilibrium fieldtheory(physics) fluctuations(physics) kritischesphänomen kritischeverschijnselen mathematischefysica percolation(statisticalphysics) phasenumwandlung phasetransformations(statisticalphysics) phy065f phénomènecritique(physique) quantumfieldtheory renormalization(physics) renormalizationgroup statisticalmechanics statisticalphysics stochasticprocesses technologicalcomplexity ug3900