Gauge-invariant Green function in 3+1 dimensional QED (QCD) and 2+1   dimensional Abelian (Non-Abelian) Chern-Simon theory
  By applying the simple and effective method developed to study the the gauge-invariant fermion Green function in $ 2+1 $ dimensional non-compact QED, we study the gauge-invariant Green function in $ 3+1 $ dimensional QED and $ 2+1 $ dimensional non-compact Chern-Simon theory. We also extend our results to the corresponding $ SU(M) $ non-Abelian gauge theories. Implications for Fractional Quantum Hall effect are briefly discussed. 
Jinwu Ye (Penn State Univ.)