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arXiv · 1910.07546

A more attractive scheme for radion stabilization and supercooled phase transition

Abstract

We propose a new radion stabilization mechanism in the Randall-Sundrum spacetime, introducing a bulk ${SU(N_H)}$ gauge field which confines at a TeV scale. It turns out that the radion is stabilized by the balance between a brane tension and a pressure due to the Casimir energy of the strong ${SU(N_H)}$ gauge field. We investigate the phase transition between the Randall-Sundrum (compactified) spacetime and a de-compactified spacetime and determine the parameter regime in which eternal (old) inflation is avoided and the phase transition can be completed. In comparison to the Goldberger-Wise mechanism, the 5D Planck mass can be larger than the AdS curvature and a classical description of the gravity is reliable in our stabilization mechanism. We also discuss the effect of the phase transition in cosmology such as an entropy dilution and a production of gravitational waves.

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Kohei Fujikura, Yuichiro Nakai, Masaki Yamada. 2019-10-16. A more attractive scheme for radion stabilization and supercooled phase transition. https://doi.org/10.1007/jhep02(2020)111

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