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arXiv 1202.4825gr-qchep-th
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膜- $f(R)$引力和暗物质

Brane-$f(R)$ gravity and dark matter

A. S. Sefiedgar, Z. Haghani, H. R. Sepangi

摘要:

在膜- $f(R)$引力的上下文中使用无碰撞玻尔兹曼方程来导出维里定理。结果表明,维里质量与爱因斯坦场方程中的某些几何项成正比,并对引力能有贡献,这种几何质量可归因于星系团中的维里质量差异.另外,利用共形对称性和共形Killing对称性的概念,研究了星系的自转曲线。然后,场方程可以根据表示共形因子的参数以精确的参数形式获得。这为研究在稳定圆轨道上运动的试验粒子的角速度的行为提供了可能。切向速度可以作为保形因子和积分常数的函数导出,从而在大径向距离处得到恒定值。研究了光在旋转曲线平坦区域的偏转和雷达回波延迟等相关现象。

英文摘要:

The collision-free Boltzmann equation is used in the context of brane-$f(R)$ gravity to derive the virial theorem. It is shown that the virial mass is proportional to certain geometrical terms appearing in the Einstein field equations and contributes to gravitational energy and that such a geometric mass can be attributed to the virial mass discrepancy in a cluster of galaxies. In addition, the galaxy rotation curves are studied by utilizing the concept of conformal symmetry and notion of conformal Killing symmetry. The field equations may then be obtained in an exact parametric form in terms of the parameter representing the conformal factor. This provides the possibility of studying the behavior of the angular velocity of a test particle moving in a stable circular orbit. The tangential velocity can be derived as a function of the conformal factor and integration constants, resulting in a constant value at large radial distances. Relevant phenomenon such as the deflection of light passing through a region where the rotation curves are flat and the radar echo delay are also studied.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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