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arXiv · 1412.4672

Spherically symmetric solutions of light Galileon

D. Momeni·M. J. S. Houndjo·E. Güdekli·M. E. Rodrigues·F. G. Alvarenga·R. Myrzakulov
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Abstract

We have been studied the model of light Galileon with translational shift symmetry $\phi\to \phi+c$. The matter Lagrangian is presented in the form $\mathcal{L}_{\phi}= -\eta (\partial \phi)^2+\beta G^{\mu\nu}\partial_{\mu}\phi\partial_{\nu}\phi$. We have been addressed two issues: the first is that, we have been proven that, this type of Galileons belong to the modified matter-curvature models of gravity in type of $f(R,R^{\mu\nu}T_{\mu\nu}^m)$. Secondly, we have been investigated exact solution for spherically symmetric geometries in this model. We have been found an exact solution with singularity at $r=0$ in null coordinates. We have been proven that the solution has also a non-divergence current vector norm. This solution can be considered as an special solution which has been investigated in literature before, in which the Galileon's field is non-static (time dependence). Our scalar-shift symmetrized Galileon has the simple form of $\phi=t$, which it is remembered by us dilaton field.

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D. Momeni, M. J. S. Houndjo, E. Güdekli, M. E. Rodrigues, F. G. Alvarenga, R. Myrzakulov. 2014-12-06. Spherically symmetric solutions of light Galileon. https://doi.org/10.1007/s10773-015-2762-4

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