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arXiv · 1709.08732

Non-Abelian cosmic string in the Starobinsky model of gravity

J. P. Morais Graça·A. de Pádua Santos·Eugênio R. Bezerra de Mello·V. B. Bezerra
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Abstract

In this paper, we analyze numerically the behaviour of the solutions corresponding to a non-Abelian cosmic string in the framework of the Starobinsky model, i.e. where $f(R)=R + ζR^2$. We perform the calculations for both an asymptotically flat and asymptotically (anti)de Sitter spacetimes. We found that the angular deficit generated by the string decreases as the parameter $ζ$ increases, in the case of a null cosmological constant. For a positive cosmological constant, we found that the cosmic horizon is affected in a non-trivial way by the parameter $ζ$.

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J. P. Morais Graça, A. de Pádua Santos, Eugênio R. Bezerra de Mello, V. B. Bezerra. 2017-09-25. Non-Abelian cosmic string in the Starobinsky model of gravity. https://doi.org/10.1142/s0218271818500128

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