statistical mechanics

n. branch of physics that deals with and examines macroscopic systems by implementing statistical principles to their microscopic components

Statistical mechanics is the application of probability theory, which includes mathematical tools for dealing with large populations, to the field of mechanics, which is concerned with the motion of particles or objects when subjected to a force.It provides a framework for relating the microscopic properties of individual atoms and molecules to the macroscopic or bulk properties of materials that can be observed in everyday life, therefore explaining thermodynamics as a natural result of statistics and mechanics (classical and quantum) at the microscopic level. In particular, it can be used to calculate the thermodynamic properties of bulk materials from the spectroscopic data of individual molecules.
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Noun
1. the branch of physics that makes theoretical predictions about the behavior of macroscopic systems on the basis of statistical laws governing its component particles
(hypernym) physics, physical science, natural philosophy