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arXiv 0811.3143astro-phgr-qc
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将MOND和暗物质混合?

Reconciling MOND and dark matter?

Jean-Philippe Bruneton, Stefano Liberati, Lorenzo Sindoni, Benoit Famaey

摘要:

对星系的观测表明,在任何半径的暗物质的引力和所包含的重子质量之间存在一对一的解析关系,这种关系由米尔格罗姆的修正牛顿动力学定律(MOND)总结。然而,现今的MOND协变版本通常需要一些额外的场来贡献几何,以及额外的热暗物质成分来解释星系团动力学和宇宙学。在这里,我们设想了一个稍微平凡的解释,表明暗物质确实存在,但它是星系中MOND现象的来源。我们假设暗物质的正则作用量,但也增加了重子物质,引力和暗物质之间的相互作用项,使标准物质有效地服从MOND场方程的星系。我们发现,即使是最简单的实现框架导致一个模型,再现一些唯象预测的冷暗物质(CDM)和MOND在这些尺度上,这些是最成功的。引入介质密度作为新的序参量,我们还设计了一种更一般形式的相互作用项。这就产生了新的物理效应,在不久的将来应该可以进行观测测试。因此,这个非常一般的框架,它可以进一步与广义标量张量理论,开辟了一个可能的统一的CDM和MOND的成功在不同的尺度。

英文摘要:

Observations of galaxies suggest a one-to-one analytic relation between the inferred gravity of dark matter at any radius and the enclosed baryonic mass, a relation summarized by Milgrom's law of modified Newtonian dynamics (MOND). However, present-day covariant versions of MOND usually require some additional fields contributing to the geometry, as well as an additional hot dark matter component to explain cluster dynamics and cosmology. Here, we envisage a slightly more mundane explanation, suggesting that dark matter does exist but is the source of MOND-like phenomenology in galaxies. We assume a canonical action for dark matter, but also add an interaction term between baryonic matter, gravity, and dark matter, such that standard matter effectively obeys the MOND field equation in galaxies. We show that even the simplest realization of the framework leads to a model which reproduces some phenomenological predictions of cold dark matter (CDM) and MOND at those scales where these are most successful. We also devise a more general form of the interaction term, introducing the medium density as a new order parameter. This allows for new physical effects which should be amenable to observational tests in the near future. Hence, this very general framework, which can be furthermore related to a generalized scalar-tensor theory, opens the way to a possible unification of the successes of CDM and MOND at different scales.

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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