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arXiv 1604.01099astro-ph.GA
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星系自转曲线减速参数的一种新估计

A new estimator of the deceleration parameter from galaxy rotation curves

Maurice H. P. M. van Putten

摘要:

暗能量的性质可以通过减速参数$q(z)$在红移$z=0$处的导数$Q=\left.dq(z)/dz\right|_0$来探测。如果是$Q<1$,则可能是静态的,如果是$Q>2.5$,则可能是动态的,分别支持$Λ$ CDM或$Λ=(1-q)H^2$,其中$H$表示Hubble参数。我们推导出$q=1-\left(4πa_0/cH\right)^{2}$,通过测量银河系自转曲线中的Milgrom参数$a_0(z)$来确定$q(z)$,该参数等价于自转速度$V_c$和重子质量$M_b$之间的Tully-Fisher关系$V^4_c=AM_b$中的系数$A$。我们推断,暗物质应该是非常轻的集群限于星系团的大小。可以想象,在空间自由落体卡文迪什型实验中可以探测到与非牛顿引力相关的过渡半径。

英文摘要:

The nature of dark energy may be probed by the derivative $Q=\left.dq(z)/dz\right|_0$ at redshift $z=0$ of the deceleration parameter $q(z)$. It is probably static if $Q<1$ or dynamic if $Q>2.5$, supporting $Λ$CDM or, respectively, $Λ=(1-q)H^2$, where $H$ denotes the Hubble parameter. We derive $q=1-\left(4πa_0/cH\right)^{2}$, enabling a determination of $q(z)$ by measurement of Milgrom's parameter $a_0(z)$ in galaxy rotation curves, equivalent to the coefficient $A$ in the Tully-Fisher relation $V^4_c=AM_b$ between rotation velocity $V_c$ and baryonic mass $M_b$. We infer that dark matter should be extremely light with clustering limited to the size of galaxy clusters. The associated transition radius to non-Newtonian gravity may conceivably be probed in a free fall Cavendish type experiment in space.

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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