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$δ$-Expansion at Finite Temperature

Rudnei O. Ramos
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Abstract

We apply the $δ$-expansion perturbation scheme to the $λϕ^{4}$ self-interacting scalar field theory in 3+1 D at finite temperature. In the $δ$-expansion the interaction term is written as $λ(ϕ^{2})^{ 1 + δ}$ and $δ$ is considered as the perturbation parameter. We compute within this perturbative approach the renormalized mass at finite temperature at a finite order in $δ$. The results are compared with the usual loop-expansion at finite temperature.

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Rudnei O. Ramos. 1996-07-24. $δ$-Expansion at Finite Temperature. https://arxiv.org/abs/hep-ph/9607416

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