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Matrix $ϕ^4$ Models on the Fuzzy Sphere and their Continuum Limits

Brian P. Dolan·Denjoe O'Connor·P. Presnajder
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Abstract

We demonstrate that the UV/IR mixing problems found recently for a scalar $ϕ^4$ theory on the fuzzy sphere are localized to tadpole diagrams and can be overcome by a suitable modification of the action. This modification is equivalent to normal ordering the $ϕ^4$ vertex. In the limit of the commutative sphere, the perturbation theory of this modified action matches that of the commutative theory.

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Brian P. Dolan, Denjoe O'Connor, P. Presnajder. 2001-09-11. Matrix $ϕ^4$ Models on the Fuzzy Sphere and their Continuum Limits. https://doi.org/10.1088/1126-6708%2F2002%2F03%2F013

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