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arXiv · 1205.3781

Vacuum Stability Conditions From Copositivity Criteria

Abstract

A scalar potential of the form $λ_{ab} ϕ_a^2 ϕ_b^2$ is bounded from below if its matrix of quartic couplings $λ_{ab}$ is copositive -- positive on non-negative vectors. Scalar potentials of this form occur naturally for scalar dark matter stabilised by a $\mathbb{Z}_2$ symmetry. Copositivity criteria allow to derive analytic necessary and sufficient vacuum stability conditions for the matrix $λ_{ab}$. We review the basic properties of copositive matrices and analytic criteria for copositivity. To illustrate these, we re-derive the vacuum stability conditions for the inert doublet model in a simple way, and derive the vacuum stability conditions for the $\mathbb{Z}_2$ complex singlet dark matter, and for the model with both a complex singlet and an inert doublet invariant under a global U(1) symmetry.

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BibTeXRIS

Kristjan Kannike. 2013-11-25. Vacuum Stability Conditions From Copositivity Criteria. https://doi.org/10.1140/epjc%2Fs10052-012-2093-z

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