ar X iv : h ep - t h / 01 07 21 9 v 3 3 0 Ju l 2 00 1 The Gauge Technique in QED 2 + 1 Yuichi

The Gauge Technique has been applied to QED2+1 in the quenched case with infrared subtraction. The behaviour of the fermion propagator near the threshold is then found to be S(p) → (γ · p+m) (p −m) ( p −m 2m ) exp(− ης 2 ), where ς = e/(4πm) and this is gauge invariant except the exponential factor. We also find a spectral function in the Landau and Yennie like gauge. The propagators S(p) are expressed in terms of Φ(z, 1, ς) explicitly .The vacuum expectation value 〈