A Short Account of the History of Structural Dynamics between the Nineteenth and Twentieth Centuries

What a difficult task it is to give a short account of the history of the structural dynamics! It’s a complex and diversified history, coming from different sources and with influences from interstitial (or interface) areas, moving between different branches of engineering, crossing them transversally and deriving from each a new impulse for development. Moreover, dynamics is a field emerging somewhere between mathematics, physics and mechanics. Also, dynamics has evolved into more disciplines: applied mathematics, theoretical mechanics, and experimental physics. The oldest of these disciplines is applied dynamics, which originally was regarded as a branch of natural philosophy or physics related to natural phenomena, and its origin goes back to Galileo Galilei (1564-1642), at least. Nevertheless, dynamics is very old discipline. The history of dynamics started with the studies of Aristotle (384-322 B.C.). Aristotle’s Physics was the first step on a long journey. Aristotle thought deeply about two fundamental questions debated by Parmenides (Fifth century B.C.) and Heracleitus (c.550-480 B.C.), on the reality and mechanisms of dynamics. What is change? Is it real? Why do things change? Aristotle realised that we understand change through duality. He modelled physical change with ‘matter’ and ‘form’. Going beyond physics, he modelled metaphysical change with ‘potency’ and ‘act’. Zeno of Elea (490-430 B.C.) developed many arguments showing that motion is impossible. Zeno’s paradoxes support the position of Parmenides, who felt that reality was eternal and motion an illusion. (The invention of the calculus by Newton and Leibniz would make the logical treatment of motion, continuity and infinity live issues in mathematics).