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arXiv · 1605.00750

On the Light dilaton in the Large N Tri-critical O(N) Model

Hamid Omid·Gordon W. Semenoff·L. C. R. Wijewardhana
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Abstract

The leading order of the large N limit of the O(N) symmetric phi-six theory in three dimensions has a phase which exhibits spontaneous breaking of scale symmetry accompanied by a massless dilaton which is a Goldstone boson. At the next-to-leading order in large N, the phi-six coupling has a beta function of order 1/N and it is expected that the dilaton acquires a small mass, proportional to the beta function and the condensate. In this note, we show that this "light dilaton" is actually a tachyon. This indicates an instability of the phase of the theory with spontaneously broken approximate scale invariance.

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Hamid Omid, Gordon W. Semenoff, L. C. R. Wijewardhana. 2016-05-03. On the Light dilaton in the Large N Tri-critical O(N) Model. https://doi.org/10.1103/physrevd.94.125017

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