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arXiv 1202.2233astro-ph.COgr-qc
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Horava-Lifshitz引力理论中的旋涡星系旋转曲线

Spiral galaxies rotation curves in the Horava - Lifshitz gravity theory

Vincenzo F. Cardone, Monica Capone, Ninfa Radicella, Matteo L. Ruggiero

摘要:

我们专注于一个修改后的Horava-Lifschitz理论,特别是,我们考虑了它的弱场静态球对称极限对星系动力学的影响。在以前的文章中,我们用这个理论得到的修正引力势计算了以球形截尾幂律球和双指数盘为唯一引力场源的银河系自转曲线,并指出修正的自转曲线与数据不一致。为了更进一步,我们在这里还包括了来自暗物质晕的贡献,以查看这是否有助于拟合旋转曲线数据。作为一个测试案例,我们考虑一个样本的螺旋星系光滑的重子物质分布和良好的测量圆速度剖面。事实证明,尽管可以找到与数据的边际一致性,但只有当暗物质晕具有不切实际的小维里质量和难以置信的大浓度时,才能获得这种一致性。这样的结果可以解释为一个强有力的证据,反对我们考虑的Horava-Lifschitz理论的修正版本中获得的引力势的可靠性。

英文摘要:

We focus on a modified version of Horava - Lifschitz theory and, in particular, we consider the impact of its weak - field static spherically symmetric limit on the galaxy dynamics. In a previous paper, we used the modified gravitational potential obtained in this theory to evaluate the Milky Way rotation curve using a spheroidal truncated power - law bulge and a double exponential disc as the only sources of the gravitational field and showed that the modified rotation curved is not in agreement with the data. Making a step forward, we here include also the contribution from a dark matter halo in order to see whether this helps fitting the rotation curve data. As a test case, we consider a sample of spiral galaxies with smooth baryon matter distribution and well measured circular velocity profiles. It turns out that, although a marginal agreement with the data can be found, this can only be obtained if the dark matter halo has an unrealistically small virial mass and incredibly large concentration. Such results can be interpreted as a strong evidence against the reliability of the gravitational potential obtained in the modified version of Horava -Lifschitz theory that we consider.

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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