NEGATIVE-ENERGY DENSITY AND CLASSICAL ELECTRON MODELS

We discuss the fact, pointed out by Bonnor and Cooperstock, that the e lectron, modelled as a spherically symmetric charged distribution of m atter (in the context of general relativity), must contain some negati ve rest mass if its radius is not larger than 10(-16) cm. Analysing so me extended electron models, we show that negative energy density dist ributions result from the requirement that the total mass of these mod els remains constant in the limit of a point particle.