In superfluid dark matter (SFDM), the phonon field plays a double role: It carries the superfluid's energy density and it mediates the MOND-like phonon force. We show that these two roles are in tension with each other on galactic scales: A MOND-like phonon force is in tension with a superfluid in equilibrium and with a significant superfluid energy density. To avoid these tensions, we propose a model where the two roles are split between two different fields. This also allows us to solve a stability problem in a more elegant way than standard SFDM. We argue that the standard estimates for the size of a galaxy's superfluid core need to be revisited.

中文翻译：

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超流体暗物质的三个问题及其解决办法

在超流体暗物质 (SFDM) 中，声子场扮演着双重角色：它携带超流体的能量密度，并介导类似 MOND 的声子力。我们表明，这两个角色在星系尺度上彼此处于紧张状态：类似 MOND 的声子力与处于平衡状态的超流体和显着的超流体能量密度处于紧张状态。为了避免这些紧张，我们提出了一个模型，其中两个角色在两个不同的领域之间分配。这也使我们能够以比标准 SFDM 更优雅的方式解决稳定性问题。我们认为需要重新审视对星系超流体核心大小的标准估计。