Dimensionally regularized study of nonperturbative quenched QED
نویسنده
چکیده
We study the dimensionally regularized fermion propagator Dyson-Schwinger equation in quenched nonperturbative QED in an arbitrary covariant gauge using the Curtis-Pennington vertex and perform nonperturbative renormalization numerically. The nonperturbative fermion propagator is solved in D ≡ 4 − 2ǫ < 4 dimensional Euclidean space for a large number of values of ǫ for two values of the coupling, α = 0.6 and α = 1.5. Results for D = 4 are then obtained by extrapolation to ǫ → 0. We compare these results against previous studies employing a modified ultraviolet cut-off regularization and find agreement to within the numerical precision of the present calculations.
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