Angular Momentum Induced In The Fermionic Vacuum On A   Rotationally-Symmetric Noncompact Riemann Surface
  The influence of spatial geometry on the vacuum polarization in 2+1-dimensional spinor electrodynamics is investigated. The vacuum angular momentum induced by an external static magnetic field is found to depend on global geometric surface characteristics connected with curvature. The relevance of the results obtained for the fermion number fractionization is discussed. 
Yu. A. Sitenko and D. G. Rakityansky