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arXiv · hep-th/9412015

Some Interesting Properties of Field theories with an Infinite Number of Fields

N. Itzhaki
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Abstract

We give an indication that gravity coupled to an infinite number of fields might be a renormalizable theory. A toy model with an infinite number of interacting fermions in four-dimentional space-time is analyzed. The model is finite at any order in perturbation theory. However, perturbation theory is valid only for external momenta smaller than $λ^{-\frac{1}{2}}$ , where $λ$ is the coupling constant.

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N. Itzhaki. 1994-12-02. Some Interesting Properties of Field theories with an Infinite Number of Fields. https://doi.org/10.1142/s0217751x98000275

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