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arXiv · 1310.4615

I-ball formation with logarithmic potential

Masahiro Kawasaki·Naoyuki Takeda
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Abstract

A coherently oscillating real scalar field with potential shallower than quadratic one fragments into spherical objects called I-balls. We study the I-ball formation for logarithmic potential which appears in many cosmological models. We perform lattice simulations and find that the I-balls are formed when the potential becomes dominated by the quadratic term. Furthermore, we estimate the I-ball profile assuming that the adiabatic invariant is conserved during formation and obtain the result that agrees to the numerical simulations.

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Masahiro Kawasaki, Naoyuki Takeda. 2015-05-27. I-ball formation with logarithmic potential. https://doi.org/10.1088/1475-7516%2F2014%2F07%2F038

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