ABSTRACT
In this chapter, we will outline briefly the introductory concepts of the Theory of Elasticity, which we call Local Theory, and the theory of Gradient Elasticity, which we call Non-Local Theory. The wave propagation analysis requires the derivation of a governing differential equation and its solution to obtain both the wavenumbers and wave responses. While for conventional structures and materials, understanding of the theory of elasticity is necessary for derivation of governing equations, for analysis of nanostructures, where small-scale effects are predominant, knowledge of non-local theory is essential to derive the governing equations.
