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arXiv · 1002.2566

Quantum field theory without divergences

M. V. Altaisky
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Abstract

It is shown that loop divergences emerging in the Green functions in quantum field theory originate from correspondence of the Green functions to {\em unmeasurable} (and hence unphysical) quantities. This is because no physical quantity can be measured in a point, but in a region, the size of which is constrained by the resolution of measuring equipment. The incorporation of the resolution into the definition of quantum fields $ϕ(x)\toϕ^{(A)}(x)$ and appropriate change of Feynman rules results in finite values of the Green functions. The Euclidean $ϕ^4$-field theory is taken as an example.

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M. V. Altaisky. 2013-05-07. Quantum field theory without divergences. https://doi.org/10.1103/physrevd.81.125003

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