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arXiv · hep-lat/9610001

Continuum Behaviour of Lattice QED, Discretized with One-Sided Lattice Differences, in One-Loop Order

Neda Sadooghi·Heinz J. Rothe
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Abstract

A lattice action for QED is considered, where the derivatives in the Dirac operator are replaced by one-sided lattice differences. A systematic expansion in the lattice spacing of the one-loop contribution to the fermion self energy, vacuum polarization tensor and vertex function is carried out for an arbitrary choice of one-sided lattice differences. It is shown that only the vacuum polarization tensor possesses the correct continuum limit, while the fermion self energy and vertex function receive non-covariant contributions. A lattice action, discretized with a fixed choice of one-sided lattice differences therefore does not define a renormalizable field theory. The non-covariant contributions can however be eliminated by averaging the expressions over all possible choices of one-sided lattice differences.

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Neda Sadooghi, Heinz J. Rothe. 1996-11-15. Continuum Behaviour of Lattice QED, Discretized with One-Sided Lattice Differences, in One-Loop Order. https://doi.org/10.1103/physrevd.55.6749

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