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Lattice effective potential of massless $(lambdaPhi^4)_4$: `triviality and spontaneous symmetry breaking

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 نشر من قبل ul
 تاريخ النشر 1995
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We present a precise lattice computation of the slope of the effective potential for massless $(lambdaPhi^4)_4$ theory in the region of bare parameters indicated by the Brahms analysis of lattice data. Our results confirm the existence on the lattice of a remarkable phase of $(lambdaPhi^4)_4$ where Spontaneous Symmetry Breaking is generated through ``dimensional transmutation. The resulting effective potential shows no evidence for residual self-interaction effects of the shifted `Higgs field $h(x)=Phi(x)-langlePhirangle$, as predicted by ``triviality, and cannot be reproduced in perturbation theory. Accordingly the mass of the Higgs particle, by itself, does not represent a measure of any observable interaction.



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