Constraining dark matter self-interactions with simulations and observations

宇宙学的标准模型假设暗物质仅通过引力与自身以及其他物质和能量相互作用。这是最简单的暗物质模型，它很好地描述了我们对宇宙的广泛观察。然而，最近对小尺度观测的比较似乎与理论预测不一致，这可能表明暗物质比以前假设的要复杂得多。从粒子物理学的角度来看，有强大的理论理由相信暗物质应该与自身弱相互作用，但这些相互作用的复杂程度却知之甚少。我们将探索自相互作用暗物质（SIDM）在大范围尺度上的后果，使用完整的宇宙流体动力学模拟，超越最简单的弹性散射假设。我们将与各种观测结果进行比较，以确定SIDM与标准模型提供了可接受的张力解决方案。

The standard model of cosmology assumes that dark matter interacts with itself and with other matter and energy via gravity only. This is the simplest possible model for dark matter and it describes a wide range of observations of our Universe quite well. However, recent comparisons to observations on small scales appear at odds with theoretical predictions, which might suggest that dark matter is more complex than previously assumed. From a particle physics point of view, there are strong theoretical reasons for believing that dark matter should weakly interact with itself, but the degree of complexity of these interactions is poorly understood. We will explore the consequences of self-interacting dark matter (SIDM) on a wide range of scales using full cosmological hydrodynamical simulations, going beyond the simplest assumption of elastic scattering. We will make comparisons to a variety of observations to determine with SIDM provides an acceptable solution to the tensions with the standard model.