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arXiv · 1403.1865

Gauss-Bonnet Boson Stars with a Single Killing Vector

Abstract

We construct asymptotically anti-de Sitter boson stars in Einstein-Gauss-Bonnet gravity coupled to a $\frac{D-1}{2}$-tuplet of complex massless scalar fields both perturbatively and numerically in D=5,7,9,11 dimensions. These solutions possess just a single helical Killing symmetry due to the choice of scalar fields. The energy density at the centre of the star characterizes the solutions, and for each choice of the Gauss-Bonnet coupling $α$ we obtain a one parameter family of solutions. All solutions respect the first law of thermodynamics; in the numerical case to within 1 part in $10^6$. We describe the dependence of the angular velocity, mass, and angular momentum of the boson stars on $α$ and on the dimensionality. For D>5, these quantities exhibit damped oscillations about finite central values as the central energy density tends to infinity, where the amplitude of oscillation increases nonlinearly with $α$. In the limit of diverging central energy density, the Kretschmann invariant at the centre of the boson star also diverges. This is in contrast to the D=5 case, where the Kretschmann invariant diverges at a finite value of the central energy density.

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BibTeXRIS

Laura J. Henderson, Robert B. Mann, Sean Stotyn. 2014-05-27. Gauss-Bonnet Boson Stars with a Single Killing Vector. https://doi.org/10.1103/physrevd.91.024009

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