The Replica Approach: Spin and Structural Glasses

A spin glass is a type of magnetic ordering that can emerge, most transparently, when a system is both frustrated and has quenched disorder. This paper will review some of the basics of such systems, and then touch on some of the experimental results that served as a guide for the theory. In exploring the theory it will focus on one particular framework, the replica approach, that has been used to study such systems, and will briefly examine how that framework is being expanded to look not only at spin but also structural glasses.