The concept of dark matter has been imported to explain the observed velocity profile of the spiral galaxies, the flat rotational velocity. Taking the flatness of rotation curves as an input and assuming that the galactic halo is filled with charged perfect fluid having known mass density function, we obtain a space time metric in the galactic halo region. The acquired solution indicates to a (nearly) flat universe, consistent with the present day cosmological observations. Various other aspects of the solution such as attractive gravity in the halo region, stability of the circular orbit, etc., are also analyzed.

中文翻译：

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带电完美流体暗物质模型：已知质量密度函数方法

引入了暗物质的概念来解释观测到的螺旋星系的速度剖面，即平面旋转速度。以旋转曲线的平坦度作为输入，假设星系晕充满了具有已知质量密度函数的带电完美流体，我们得到了星系晕区域的时空度量。获得的解决方案表明（几乎）平坦的宇宙，与当今的宇宙学观测一致。还分析了该解决方案的各个其他方面，例如晕区的吸引力、圆形轨道的稳定性等。