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On a mean field approximation for Higgs-Yukawa systems

Sergei V. Zenkin
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Abstract

We discuss the phase structure of a lattice Higgs-Yukawa system in the variational mean field approximation with contributions of fermionic determinant being calculated in a ladder approximation. In particular, we demonstrate that in this approximation the ferrimagnetic phase in the $Z_2$ model with naive fermions can appear as an artifact of a finite lattice and that the phase diagram for this model on infinite lattice changes qualitatively at space-time dimension $D = 4$ compared with those at $D > 4$.

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Sergei V. Zenkin. 1993-09-10. On a mean field approximation for Higgs-Yukawa systems. https://doi.org/10.1142/s0217732394000824

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