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On generalized wormhole in the Eddington inspired Born-Infeld (EiBI) gravity

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 نشر من قبل Ramil Izmailov
 تاريخ النشر 2015
  مجال البحث فيزياء
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In this paper, we wish to investigate certain observable effects in the recently obtained wormhole solution of the EiBI theory, which generalizes the zero mass Ellis-Bronnikov wormhole of general relativity. The solutions of EiBI theory contain an extra parameter $kappa$ having the inverse dimension of the cosmological constant $Lambda$, and is expected to modify various general relativistic observables such as the masses of wormhole mouths, tidal forces and light deflection. A remarkable result is that a non-zero $kappa$ could prevent the tidal forces in the geodesic orthonormal frame from becoming arbitrarily large near a small throat radius $(r_0 sim {0})$ contrary to what happens near a small Schwarzschild horizon radius $(M sim 0)$. The role of $kappa$ in the flare-out and energy conditions is also analysed, which reveals that the energy conditions are violated. We show that the exotic matter in the EiBI wormhole cannot be interpreted as phantom $({omega}=(p_{r}/ rho)<-1)$ or ghost field ${phi} $ of general relativity due to the fact that both $rho$ and $p_{r}$ are negative for all $kappa$.



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