标题： 霍尔德斯基帮助哈勃：通过霍尔德斯基引力解决哈勃张力的可能方案 显示英文标题

标题： Horndeski Helping Hubble: Towards a possible solution to the Hubble tension with Horndeski gravity

摘要： 哈勃张力指的是从宇宙微波背景和超新星观测中推断出的哈勃常数$H_0$值之间的差异。 为了缓解这种张力，我们提出对标准$\Lambda$CDM 模型进行修改，在霍纳德斯基引力框架下用动态标量场代替宇宙学常数$\Lambda$，这驱动了宇宙的晚期加速膨胀阶段。 通过结合霍纳德斯基拉格朗日量中的$G_4$和$G_5$项，我们表明，可以构建可行的场景来缓解哈勃张力，这些场景不受梯度和鬼魅不稳定性以及标量和张量扰动超光速传播的影响。 在两种不同的标量势类别以及适当选择模型参数的情况下，我们表明可以获得足够大的$H_0$值，以与晚期宇宙观测一致。 由于这些修改在早期时间非常微小，因此在高红移下，它们与$\Lambda$CDM 宇宙学的偏差完全可以忽略。 显示英文摘要

摘要： The Hubble tension refers to the discrepancy in the value of the Hubble constant $H_0$ inferred from the cosmic microwave background and the supernovae observations. In order to alleviate this tension, we propose a modification to the standard $\Lambda$CDM model by replacing the cosmological constant $\Lambda$ with a dynamical scalar field in the framework of Horndeski gravity, which drives the late time accelerated expanding phase of the Universe. With a combination of the $G_4$ and $G_5$ terms of the Horndeski Lagrangian, we show that, it is possible to construct viable scenarios for alleviating the Hubble tension which are free from gradient and ghost instabilities and the superluminal propagation of the scalar and tensor perturbations. Working with two different classes of scalar field potentials and with appropriate choices of model parameters, we exhibit that one can obtain a large enough value of $H_0$, so as to be consistent with the late Universe observations. Since these modifications are extremely small at early times, the corresponding deviations from the $\Lambda$CDM cosmology are completely negligible at high redshifts.