Der Einführungsband klärt Inhalt und Grenzen des Begriffs "Sozialpolitik" und stellt wichtige Quellengruppen und ihre Fundorte im Überblick vor. In Form einer Chronik bietet er dem Benutzer eine Orientierung über Daten, die den Verlauf der Sozialpolitik entscheidend bestimmt haben.

The various approximations of vacuum polarization potential and the higher order corrections up to \alpha^3 are reviewed and quantitatively dicussed. The quadrupol part of the vacuum polarization is established. It leads rather straight forward to a small contribution of vacuum polarization to nuclear polarization. These effects are quantitatively investigated.

With a relativistic Hartree-Fock-Slater calculation we determined the most stable configurations of the elements of the possibly quasistable island around Z = 164. It is found that the expected noble gas at Z = 168 should not occur, but instead the element Z = 164 should have the properties of a noble gas.