Conditions for Existence of Compact Stationary Relativistic Beam Torus
  Conditions for obtaining the absolute magnetic trap (AMT) to be used for the controlled fusion by means of high power relativistic charged beam have been considered. It is shown that AMT can not be created by external electromagnetic fields. Also the virial theorem implies that strict stationary state of the system does not exist in empty flat Minkowski space-time in case of positive beam pressure and positive electromagnetic field energy density. 
Yu.A. Khlestkov, L.A. Sukhanova