### Media

Paper# EmQM13 – Spin and Charge from Space and Time

Manfried Faber, Vienna University of Technology, AT#### Abstract

From his electrolysis experiments Michael Faraday concluded that the electric charge has a discrete character, it is quantised. A property not taken into account by quantum mechanics, where the electric charge can have any real value. We discuss a field model where the charge q=Ze_0 is given by a topological quantum number Z, the integer multiple of elementary charges e_0. Z classifies the map from R³ to S². In this description a U(1) gauge symmetry appears in a natural way. Maps from R³ to SO(3) allow to relate the spin quantum numbers to another topological quantum number, usually called the topological charge. How spin-1/2 particles could realise their specific properties under 4 pi rotations is investigated. We know from quantum mechanics that the spin gives an important contribution to the total angular momentum. We discuss how the angular momentum properties of particles are realised in the above model by the time dependence of the field configurations.