标题： 同时解决哈勃张力和250${h^{-1}}$Mpc范围内的观测Bulk Flow问题 显示英文标题

标题： A simultaneous solution to the Hubble tension and observed bulk flow within 250 ${h^{-1}}$ Mpc

摘要： The $\Lambda$ cold dark matter ($\Lambda$CDM) standard cosmological model is in severe tension with several cosmological observations. Foremost is the Hubble tension, which exceeds $5\sigma$ confidence. Galaxy number counts show the Keenan-Barger-Cowie (KBC) supervoid, a significant underdensity out to 300~Mpc that cannot be reconciled with $\Lambda$CDM cosmology. Haslbauer et al. previously showed that a high local Hubble constant arises naturally due to gravitationally driven outflows from the observed KBC supervoid. The main prediction of this model is that peculiar velocities are typically much larger than expected in the $\Lambda$CDM framework. This agrees with the recent discovery by Watkins et al. that galaxies in the CosmicFlows-4 catalogue have significantly faster bulk flows than expected in the $\Lambda$CDM model on scales of $100-250 \, h^{-1}$~Mpc. 在标准宇宙学中，上升的Bulk Flow曲线出乎意料，导致了$4.8\sigma$和$200 \, h^{-1}$~Mpc之间的张力。 在这项工作中，我们确定了 Haslbauer 等人提出的半解析void模型对这些尺度上的Bulk Flow的预测。 我们发现与观测结果在定性上一致，特别是在我们的视角被选择为匹配$50 \, h^{-1}$~Mpc尺度上的观测Bulk Flow时。 这代表了一个先前发表的模型的高度非平凡的成功，该模型未受到Bulk Flow测量的约束，但被证明可以解决Hubble张力，并且以本地星系群的peculiar velocity一致地解释KBC void。 我们的结果表明，如果结构在几十到几百Mpc的尺度上比在$\Lambda$CDM范式下更有效地增长，则几个宇宙学张力可以同时得到解决。 显示英文摘要

摘要： The $\Lambda$ cold dark matter ($\Lambda$CDM) standard cosmological model is in severe tension with several cosmological observations. Foremost is the Hubble tension, which exceeds $5\sigma$ confidence. Galaxy number counts show the Keenan-Barger-Cowie (KBC) supervoid, a significant underdensity out to 300~Mpc that cannot be reconciled with $\Lambda$CDM cosmology. Haslbauer et al. previously showed that a high local Hubble constant arises naturally due to gravitationally driven outflows from the observed KBC supervoid. The main prediction of this model is that peculiar velocities are typically much larger than expected in the $\Lambda$CDM framework. This agrees with the recent discovery by Watkins et al. that galaxies in the CosmicFlows-4 catalogue have significantly faster bulk flows than expected in the $\Lambda$CDM model on scales of $100-250 \, h^{-1}$~Mpc. The rising bulk flow curve is unexpected in standard cosmology, causing $4.8\sigma$ tension at $200 \, h^{-1}$~Mpc. In this work, we determine what the semi-analytic void model of Haslbauer et al. predicts for the bulk flows on these scales. We find qualitative agreement with the observations, especially if our vantage point is chosen to match the observed bulk flow on a scale of $50 \, h^{-1}$~Mpc. This represents a highly non-trivial success of a previously published model that was not constrained by bulk flow measurements, but which was shown to solve the Hubble tension and explain the KBC void consistently with the peculiar velocity of the Local Group. Our results suggest that several cosmological tensions can be simultaneously resolved if structure grows more efficiently than in the $\Lambda$CDM paradigm on scales of tens to hundreds of Mpc.