Kirjahaku

1. Background This textbook is an introduction to and exploration of a number of core topics in the ?eld of applied mechanics. Mechanics, in both its theoretical and applied contexts, is, like all scienti?c endeavors, a human construct. It re?ects the personalities, thoughts, errors, and successes of its creators. We therefore provide some personal information about each of these individuals when their names arise for the ?rst time in this book. This should enable the reader to piece together a cultural-historical picture of the ?eld s origins and development. This does not mean that we are writing history. Nevertheless, some remarks putting individuals and ideas in context are necessary in order to make clear what we are speaking about – and what we are not speaking about. At the end of the 19th century, technical universities were established eve- where in Europe in an almost euphoric manner. But the practice of technical mechanics itself, as one of the basics of technical development, was in a desolate state, due largely to the refusal of its practitioners to recognize the in?uence of kinetics on motion. They were correct to the extend that then current mechanical systems moved with small velocities where kinetics does not play a signi?cant role. But they had failed to keep up with developments in the science underlying their craft and were unable to keep pace with the speeds of such systems as the steam engine.

Von Mechanik soll die Rede sein - oder zumindest einem Teilgebiet davon. Und zwar von der Mechanik, die durch GALILE! 1638 und NEWTON 1687 zum Durch­ bruch als exakte Natur-Wi33en-schaJt, von EULER 1750/75 zur Blüte und von LAGRANGE 1788 und HAMILTON 1835 zur Vollendung geführt wurde - um mit einigen Namen einen Rahmen zu stecken. Daß hierbei die Mechanik eine der ersten Naturwissenschaften war, ihr zumindest "eine Schrittmacherrolle zugefallen ist"l, macht das Thema reizvoll, ist aber natürlich kein ausreichender Grund, zu den vorhandenen Abhandlungen eine weitere hinzuzufügen. Vielmehr liegt eine gewlsse Berechtigung in dem Versuch, das vorhandene Material zu ordnen und aus einem Blickwinkel heraus zu betrachten, der den momentanen Anforderungen an die Mechanik gerecht wird. Wo steht die Mechanik heutef "Die Mechanik der Rezepte - in früheren Jahrhun­ derten durchaus effektiv - hat ausgedient. Die weitgehenden Idealisierungen, in der als klassisch bezeichneten Periode noch als angemessen und zulässig akzeptiert, müssen jetzt mehr und mehr abgebaut und durch realistischere Annahmen ersetzt werden" 1. Dies kennzeichnet einen Wandel von einer "Ideal-Mechanik zu einer Real-Mechanik" 1. Als Realmechnik kann die Mechanik, die früher Vorbildcharak­ ter für andere Wissenschaften hatte, "wieder beispielgebend sein oder werden. Wir sollten uns also nicht von dem gelegentlichen Geschwätz über die angeblich abge­ schlossene und damit nicht mehr entwicklungsfähige Mechanik verwirren lassen.

1. Background This textbook is an introduction to and exploration of a number of core topics in the ?eld of applied mechanics. Mechanics, in both its theoretical and applied contexts, is, like all scienti?c endeavors, a human construct. It re?ects the personalities, thoughts, errors, and successes of its creators. We therefore provide some personal information about each of these individuals when their names arise for the ?rst time in this book. This should enable the reader to piece together a cultural-historical picture of the ?eld s origins and development. This does not mean that we are writing history. Nevertheless, some remarks putting individuals and ideas in context are necessary in order to make clear what we are speaking about – and what we are not speaking about. At the end of the 19th century, technical universities were established eve- where in Europe in an almost euphoric manner. But the practice of technical mechanics itself, as one of the basics of technical development, was in a desolate state, due largely to the refusal of its practitioners to recognize the in?uence of kinetics on motion. They were correct to the extend that then current mechanical systems moved with small velocities where kinetics does not play a signi?cant role. But they had failed to keep up with developments in the science underlying their craft and were unable to keep pace with the speeds of such systems as the steam engine.