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Isolation and Expulsion of Divergences in Quantum Field Theory

John R. Klauder
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Abstract

Divergences that arise in the quantization of scalar quantum field models by means of a lattice-space functional integration may be attributed to a single integration variable, and this fact is demonstrated by showing that if the integrand for that single integration variable is appropriately changed, then a perturbation expansion becomes order-by-order finite and divergence free. The paper concludes with a brief review of a current proposal of how an auxiliary, nonclassical potential added to the lattice action of a relativistic scalar field quantization may automatically render an analogous change of the integrand, and thus may lead, as well, to nontrivial and divergence-free results.

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John R. Klauder. 1995-10-11. Isolation and Expulsion of Divergences in Quantum Field Theory. https://doi.org/10.1142/s0217979296000581

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