It is usually believed that MOND can describe the galactic rotational curveswith only baryonic matter and without any dark matter very well, while the$\Lambda$CDM model is expected to have difficulty in reproducing MOND-likebehavior. Here, we use EAGLE's data to learn whether the $\Lambda$CDM model canreproduce MOND-like behavior. EAGLE's simulation result clearly reproduces theMOND-like behavior for $a_b\gtrapprox 10^{-12}\text{m/s}^2$ at $z=0$, althoughthe acceleration constant, $a_0$, is a little larger than the observationaldata indicate. We find that $a_0$ increases with the redshift in a waydifferent from what Milgrom proposed ($a_0\propto H$). Therefore, while galaxyrotation curves can be fitted by MOND's empirical function in the $\Lambda$CDMmodel, there is no clear connection between $a_0$ and the Hubble constant. Wealso find that $a_0$ at $z\gtrapprox 1$ is well separated from $a_0$ at $z=0$.Once we have enough galaxies observed at high redshifts, we will be able torule out the modified gravity model based on MOND-like empirical function witha z-independent $a_0$.
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机译：通常认为MOND可以很好地描述仅具有重子物质而没有任何暗物质的星系旋转曲线，而CDM模型预计将很难再现类似MOND的行为。在这里，我们使用EAGLE的数据来了解$ \ Lambda $ CDM模型是否可以重现类似MOND的行为。 EAGLE的仿真结果清楚地再现了$ a_b \ gtrapprox 10 ^ {-12} \ text {m / s} ^ 2 $在$ z = 0 $时的类似MOND的行为，尽管加速度常数$ a_0 $略大于观测资料表明。我们发现$ a_0 $随红移的增加与Milgrom提出的建议不同（$ a_0 \ proto H $）。因此，尽管可以通过$ \ Lambda $ CDM模型中MOND的经验函数拟合星系旋转曲线，但在$ a_0 $和哈勃常数之间没有明确的联系。我们还发现$ z \ gtrapprox 1 $处的$ a_0 $与$ z = 0 $处的$ a_0 $很好地分开了。一旦在高红移处观测到足够多的星系，我们就可以排除基于MOND的修正重力模型类似于z的$ a_0 $的经验函数。
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