Olaf Richter

Die in diesem Buch prasentierten Lebensbilder einer niederrheinischen Familie zwischen Burgertum und Adel setzen im Jahr 1212 ein, fur das die ersten Nachrichten uber den Hof Etgendorf in der Julicher Borde tradiert sind. Uber die Beschreibung der Hofbesitzer und deren Landwirtschaft mundet die Erzahlung in die Lebensgeschichte ihres Nachfahren Petrus Simonius Ritz (1562-1622) sowie die Geschicke seiner Familie bis ins fruhe 19. Jahrhundert hinein. Dabei eroffnet sich den Lesern ein breites Spektrum historischer Kernthemen der Fruhen Neuzeit: familiarer Alltag, Bildung und Beruf, Religion und Gesellschaft, Krankheit und Tod.

Exact solutions to Einstein`s equations have been useful for the understanding of general relativity in many respects. They have led to physical concepts as black holes and event horizons and helped to visualize interesting features of the theory. In addition they have been used to test the quality of various approximation methods and numerical codes. The most powerful solution generation methods are due to the theory of Integrable Systems. In the case of axisymmetric stationary spacetimes the Einstein equations are equivalent to the completely integrable Ernst equation. In this volume the solutions to the Ernst equation associated to Riemann surfaces are studied in detail and physical and mathematical aspects of this class are discussed both analytically and numerically.

Exact solutions to Einstein`s equations have been useful for the understanding of general relativity in many respects. They have led to physical concepts as black holes and event horizons and helped to visualize interesting features of the theory. In addition they have been used to test the quality of various approximation methods and numerical codes. The most powerful solution generation methods are due to the theory of Integrable Systems. In the case of axisymmetric stationary spacetimes the Einstein equations are equivalent to the completely integrable Ernst equation. In this volume the solutions to the Ernst equation associated to Riemann surfaces are studied in detail and physical and mathematical aspects of this class are discussed both analytically and numerically.