In Memoriam: Harry F. Tiersten, Professor and Ph.D. 1930-2006

A brief biography of Harry F. Tiersten (1930-2006) is given highlighting his professional achievements. Professor Tiersten coauthored the IEEE Standard on Piezoelectricity and was responsible for the theoretical part. His 1969 book "Linear Piezoelectric Plate Vibrations" by Plenum has been a major reference on theoretical piezoelectricity for many years. During the study of piezoelectric resonators, in addition to linear piezoelectricity, to analyze resonator frequency stability, Professor Tiersten systematically developed the theory of nonlinear electroelasticity for large deformations and strong fields, the linear theory for infinitesimal fields superposed on finite biasing fields, and the perturbation theory for frequency shifts in piezoelectric resonators. These theories have shaped the field many researchers are working in today. His contributions also extend to theories for more general nonlinear interactions of elastic deformations with electromagnetic fields in continuous media, including thermal effects and conduction or semiconduction. He was also highly respected in the mechanics community internationally. He was considered as one of the founders of the macroscopic theories of continuum electrodynamics.