论文标题
根据宇宙学的紧张局势对早期重力过渡的探索
An exploration of an early gravity transition in light of cosmological tensions
论文作者
论文摘要
我们研究了在重组之前对有效planck质量（或有效的重力常数）值（或有效重力常数）的逐步转变。我们采用CMB，BAO和SNIA数据，发现它们足以强烈限制我们对暗能量和修饰重力的有效场理论的实施，用于对过渡建模，以建模到有限的参数空间。在重组之前，数据更喜欢有效Planck质量的$ \ sim 5 \％$偏移（$ <10 \％$ at $2σ$）。该过渡性Planck质量（TPM）模型可以在重组之前的数十年的比例系数中自由进行过渡，$ \ log_ {10}（a）= -5.32^{+0.96} _ { - 0.72} $（68 \％cl）。这降低了终于散射的声音范围，这将哈勃常数增加到$ 71.09 \ pm 0.75 $ km $ $ \ textrm {s}^{ - 1} \ 1} \ textrm {mpc}^{ - 1} $，并将本地尺寸的组合作为先前和$ 69.22^$ km} $ km组合$ \ textrm {s}^{ - 1} \ textrm {mpc}^{ - 1} $当不排除先验时。 TPM模型相对于$λ$ CDM提高了$χ^2 $，$Δχ^2 = -23.72 $，$ H_0 $ prior和$Δχ^2 = -4.8 $没有先验。 The model allows for both $H_0 > 70$ km$\textrm{s}^{-1}\textrm{Mpc}^{-1}$ and $S_8 < 0.80$ simultaneously with lower values of $S_8$ due to a reduction in the matter density $Ω_m$ to offset the increase in $H_0$ relative to $Λ$CDM.虽然这是一个特定的修饰重力模型，但研究其他重力的其他变体可能是解决宇宙学张力的有效途径，同时避免了宇宙学常数的需求。
We study a step-like transition in the value of the effective Planck mass (or effective gravitational constant) on cosmological scales prior to recombination. We employ CMB, BAO, and SNIa data and find they are sufficient to strongly constrain our implementation of the Effective Field Theory of Dark Energy and Modified Gravity, used to model the transition, to a limited parameter space. The data prefer a $\sim 5\%$ shift in the value of the effective Planck mass ($<10 \%$ at $2 σ$) prior to recombination. This Transitional Planck Mass (TPM) model is free to undergo its transition at any point over multiple decades of scale factor prior to recombination, $\log_{10}(a) = -5.32^{+0.96}_{-0.72}$ (68\% CL). This lowers the sound horizon at last scattering, which increases the Hubble constant to $71.09 \pm 0.75$ km $\textrm{s}^{-1}\textrm{Mpc}^{-1}$ with a combination of local measurements as prior and to $69.22^{+0.67}_{-0.86}$ km $\textrm{s}^{-1}\textrm{Mpc}^{-1}$ when the prior is excluded. The TPM model improves $χ^2$ with respect to $Λ$CDM by $Δχ^2 = -23.72$ with the $H_0$ prior and $Δχ^2 = -4.8$ without the prior. The model allows for both $H_0 > 70$ km$\textrm{s}^{-1}\textrm{Mpc}^{-1}$ and $S_8 < 0.80$ simultaneously with lower values of $S_8$ due to a reduction in the matter density $Ω_m$ to offset the increase in $H_0$ relative to $Λ$CDM. While this is a particular modified gravity model, studying other variants of modified gravity may be a productive path for potentially resolving cosmological tensions, while avoiding the need for a cosmological constant.
