Cosmic structure formation is thought to occur as a bottom-up scenario, i.e. the lightest objects would have formed first. It has been suggested that the earliest structures to form could have been primordial planets. Here we propose the possibility of formation of primordial planets at high redshifts composed predominantly of dark matter (DM) particles, with planetary masses ranging from Neptune mass to asteroid mass. Most of these primordial DM planets could be free floating without being attached to a host star and a substantial fraction could be present in the halo contributing to the DM. Here we suggest that the flux of DM particles could be significantly reduced as substantial number of DM particles are now trapped in such objects, perhaps accounting for the negative results seen so far in the ongoing DM detection experiments.

中文翻译：

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主要由暗物质组成的原始行星

宇宙结构的形成被认为是自下而上的场景，即最轻的物体会首先形成。有人提出，最早形成的结构可能是原始行星。在这里，我们提出了在主要由暗物质 (DM) 粒子组成的高红移处形成原始行星的可能性，行星质量从海王星质量到小行星质量不等。这些原始 DM 行星中的大多数可以自由漂浮而不会附着在主恒星上，并且大部分可能存在于对 DM 有贡献的光晕中。在这里，我们建议 DM 粒子的流量可以显着减少，因为大量 DM 粒子现在被困在这些物体中，这可能是目前正在进行的 DM 检测实验中看到的负面结果的原因。