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Register a new userNon-topological Domain Walls in a Model with Broken Supersymmetry
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We study non-topological, charged planar walls (Q-walls) in the context of a particle physics model with supersymmetry broken by low-energy gauge mediation. Analytical properties are derived within the flat-potential approximation for the flat-direction raising potential, while a numerical study is performed using the full two-loop supersymmetric potential. We analyze the energetics of finite-size Q-walls and compare them to Q-balls, non-topological solitons possessing spherical symmetry and arising in the same supersymmetric model. This allow us to draw a phase diagram in the charge-transverse length plane, which shows a region where Q-wall solutions are more stable than Q-balls.
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In this paper the domain wall solutions of a Ginzburg-Landau non-linear $mathbb{S}^2$-sigma hybrid model are exactly calculated. There exist two types of basic domain walls and two families of composite domain walls. The domain wall solutions have been identified by using a Bogomolny arrangement in a system of sphero-conical coordinates on the sphere $mathbb{S}^2$. The stability of all the domain walls is also investigated.
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Symmetries in Quantum Field Theory may have t Hooft anomalies. If the symmetry is unbroken in the vacuum, the anomaly implies a nontrivial low-energy limit, such as gapless modes or a topological field theory. If the symmetry is spontaneously broken, for the continuous case, the anomaly implies low-energy theorems about certain couplings of the Goldstone modes. Here we study the case of spontaneously broken discrete symmetries, such as Z/2 and T. Symmetry breaking leads to domain walls, and the physics of the domain walls is constrained by the anomaly. We investigate how the physics of the domain walls leads to a matching of the original discrete anomaly. We analyze the symmetry structure on the domain wall, which requires a careful analysis of some properties of the unbreakable CPT symmetry. We demonstrate the general results on some examples and we explain in detail the mod 4 periodic structure that arises in the Z/2 and T case. This gives a physical interpretation for the Smith isomorphism, which we also extend to more general abelian groups. We show that via symmetry breaking and the analysis of the physics on the wall, the computations of certain discrete anomalies are greatly simplified. Using these results we perform new consistency checks on the infrared phases of 2+1 dimensional QCD.
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