We study light deflection from a Reissner–Nordström–de Sitter black hole in the gravitational monopole background. We first calculate the orbit equation and the contribution of the monopole and black hole parameters to the deflection angle up to second order for the vanishing cosmological constant case using the Rindler–Ishak method. We also obtain the contribution of the cosmological constant to light deflection in this geometry in the weak field limit using the same method.

中文翻译：

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Reissner–Nordström–de Sitter-单极黑洞的光线弯曲

我们研究了引力单极子背景下Reissner–Nordström–de Sitter黑洞的光偏转。我们首先使用Rindler–Ishak方法计算消失的宇宙学常数情况下的轨道方程以及单极子和黑洞参数对偏转角的贡献，直至二阶。我们还使用相同的方法在弱场限制下获得了宇宙常数对光偏转的几何形状的贡献。