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arXiv 2102.07792astro-ph.CO
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暗物质速度相关力替代宇宙学常数的相容性分析

Consistency analysis of a Dark Matter velocity dependent force as an alternative to the Cosmological Constant

Karoline Loeve, Kristine Simone Nielsen, Steen H. Hansen

摘要:

一系列的宇宙学观测证明了宇宙的加速膨胀,对这种现象最有可能的解释是宇宙学常数。考虑到理解基本物理的重要性,研究替代模型是相关的。本文使用数值模拟来测试这种替代模型的一致性。具体来说,这个模型没有宇宙学常数,相反,暗物质粒子有一个与速度平方成比例的额外力,有点让人想起电动力学中的磁力。力的恒定强度是唯一的自由参数。由于自下而上的结构形成创造了宇宙结构,其内部速度色散随时间增加,这个模型可以模拟从宇宙学常数的效果的时间演化。结果表明,力与内速度成线性比例的模型,或速度的三次方或更多成比例的模型不能模拟由宇宙学常数引起的加速膨胀。然而,与速度平方成比例的模型仍然与具有宇宙学模型的宇宙的时间演化相一致。

英文摘要:

A range of cosmological observations demonstrate an accelerated expansion of the Universe, and the most likely explanation of this phenomenon is a cosmological constant. Given the importance of understanding the underlying physics, it is relevant to investigate alternative models. This article uses numerical simulations to test the consistency of one such alternative model. Specifically, this model has no cosmological constant, instead the dark matter particles have an extra force proportional to velocity squared, somewhat reminiscent of the magnetic force in electrodynamics. The constant strength of the force is the only free parameter. Since bottom-up structure formation creates cosmological structures whose internal velocity dispersions increase in time, this model may mimic the temporal evolution of the effect from a cosmological constant. It is shown that models with force linearly proportional to internal velocites, or models proportional to velocity to power three or more cannot mimic the accelerated expansion induced by a cosmological constant. However, models proportional to velocity squared are still consistent with the temporal evolution of a Universe with a cosmological model.

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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