Horava-Lifshitz引力中的晚期宇宙加速：来自宇宙计时仪与Pantheon+SHOES数据集的观测证据
Late-Time Cosmic Acceleration in Hořava-Lifshitz Gravity: Observational Evidence from Cosmic Chronometers and Pantheon+SHOES Datasets
浏览论文内容
中文总结 AI 辅助
该研究利用宇宙计时仪与Pantheon+SHOES数据集，通过MCMC约束Horava-Lifshitz引力的参数，证实宇宙晚期加速膨胀，其演化与$\Lambda$CDM存在轻微偏差，符合类 quintessence暗能量特征。
中文摘要 AI 辅助
我们利用形式为$q(z) = q_0 + \frac{q_1 \ln(1+z)}{1 + n\ln(1+z)}$的红移相关减速参数研究Horava-Lifshitz（HL）引力的宇宙学含义，由此解析推导哈勃参数$H(z)$。该参数化方案捕捉了从早期减速到晚期加速的转变，其中由$n$控制的对数修正使其区别于标准运动学模型。我们利用宇宙计时仪（CC）和Pantheon+SHOES数据集，单独及组合地通过马尔可夫链蒙特卡洛（MCMC）约束模型参数$H_0$、$q_0$、$q_1$和$n$。在所有数据集组合中，$q_0 < 0$，证实膨胀正在加速。重构的$H(z)$在低红移时与$\Lambda$CDM一致，在高红移时存在轻微偏差。$\{r, s\}$状态 finder参数表明模型演化平滑，始于 Chaplygin气体型行为，穿过$\Lambda$CDM不动点，最终进入类 quintessence相。$Om(z)$诊断显示全程负斜率，表明类 quintessence暗能量（$w > -1$）。来自单独及组合数据集的当前宇宙年龄估计值为$t_0 \approx 13.7$ Gyr，与Planck 2018的约束一致。
英文摘要
We investigate the cosmological implications of Horava-Lifshitz (HL) gravity using a redshift-dependent deceleration parameter of the form $q(z) = q_0 + \frac{q_1 \ln(1+z)}{1 + n\ln(1+z)}$, from which the Hubble parameter $H(z)$ is derived analytically. This parametrization captures the transition from early deceleration to late-time acceleration, with a logarithmic correction governed by $n$ that distinguishes it from standard kinematic models. Model parameters $H_0$, $q_0$, $q_1$, and $n$ are constrained via MCMC using cosmic chronometer (CC) and Pantheon+SHOES datasets, individually and in combination. Across all dataset combinations, $q_0 < 0$, confirming ongoing accelerated expansion. The reconstructed $H(z)$ is consistent with $Λ$CDM at low redshifts, with mild deviations at higher redshifts. The $\{r, s\}$ statefinder parameters indicate that the model evolves smoothly, beginning with Chaplygin gas-type behaviour, crossing the $Λ$CDM fixed point, and settling into a quintessence-like phase at late times. The $Om(z)$ diagnostic reveals negative slopes throughout, indicating quintessence-like dark energy ($w > -1$). Present-day cosmic age estimates from the individual and combined datasets yield $t_0 \approx 13.7$ Gyr, in agreement with Planck 2018 constraints.
