ABSTRACT
One of the most interesting predictions of the theory of General Relativity is the existence of gravitational waves. The idea that a perturbation of the gravitational field should propagate as a wave is, in some sense, intuitive. When a gravitational wave propagates, the geometry and, consequently, the proper distance between spacetime points changes in time. Gravitational waves can be studied by solving Einstein’s equations with different approaches: “exact”, perturbative, or numerical. Exact solutions can also describe the interaction of gravitational waves which, due to the non-linearity of the equations of gravity, is very different from the interaction of electromagnetic waves. This chapter discusses the relative motion of neighbouring particles induced by a gravitational wave.
