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O(N) quintessence

Xin-zhou Li·Jian-gang Hao·Dao-jun Liu
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Abstract

We study a new class of quintessence models, in which the scalar field possesses a O(\textit{N}) internal symmetry. We give a critical condition of instability for the potential against Q ball formation. We find that the most widely used potentials of quintessence don't satisfy the above condition, and therefore the O(\textit{N}) quintessence with these potential will not lead to the Q ball formation. It is worth noting that O(\textit{N}) quintessence with cosine-type potential is especially interesting in that the angular contribution is not negligible.

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Xin-zhou Li, Jian-gang Hao, Dao-jun Liu. 2002-10-18. O(N) quintessence. https://doi.org/10.1088/0264-9381%2F19%2F23%2F311

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