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arXiv · 0712.0208

Global monopole surrounded by quintessence-like matter

Xin-zhou Li·Ping Xi·Xiang-hua Zhai
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Abstract

We present new static spherically-symmetric solutions of Einstein equations with the quintessence-like matter surrounding a global monopole. These new solutions of the coupling scalar-Einstein equations are more complicated, which depend on the parameter of equation of state $-1 < w_{q} <-{1/3}$. A gravitating global monopole produces a gravitational field of de Sitter kind outside the core in addition to a solid angular deficit. In the $w_{q} = -{1/3}$ case, we have proved that the solution cannot exist since the density of quintessence-like tends to zero if $w_{q} \to -{1/3}$. As a new feature, these monopoles have the outer horizon depending on both Goldstone field and quintessence-like. Since current observations constrain $-1.14 < w_{q} < -0.93$, new global monopoles have interesting astrophysical applications.

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Xin-zhou Li, Ping Xi, Xiang-hua Zhai. 2008-07-02. Global monopole surrounded by quintessence-like matter. https://doi.org/10.1016/j.physletb.2008.06.069

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