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arXiv · 2102.03363

Quantum scalar field theories with fractional operators

Gianluca Calcagni
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Abstract

We study a class of perturbative scalar quantum field theories where dynamics is characterized by Lorentz-invariant or Lorentz-breaking non-local operators of fractional order and the underlying spacetime has a varying spectral dimension. These theories are either ghost free or power-counting renormalizable but they cannot be both at the same time. However, some of them are one-loop unitary and finite, and possibly unitary and finite at all orders.

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Gianluca Calcagni. 2021-02-05. Quantum scalar field theories with fractional operators. https://doi.org/10.1088/1361-6382%2Fac103c

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