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arXiv · 1510.03905

Abelian cosmic string in the Starobinsky model of gravity

J. P. Morais Graça
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Abstract

In this paper, I analyze numerically the behaviour of the solutions corresponding to an Abelian string in the framework of the Starobinsky model. The role played by the quadratic term in the Lagrangian density $f(R) = R + ηR^2$ of this model is emphasized and the results are compared with the corresponding ones obtained in the framework of Einstein's theory of gravity. I have found that the angular deficit generated by the string is lowered as the $η$ parameter increases, allowing a well-behaved spacetime for a large range of values of the symmetry-breaking scale.

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J. P. Morais Graça. 2016-03-01. Abelian cosmic string in the Starobinsky model of gravity. https://doi.org/10.1088/0264-9381%2F33%2F5%2F055004

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