标题： 被瞄准的动力学暗能量：DESI、Pantheon plus和TDCOSMO约束的联合分析 显示英文标题

标题： Dynamical Dark Energy in the Crosshairs: A Joint Analysis with DESI, Pantheon plus, and TDCOSMO Constraints

摘要： 在这项工作中，我们使用最新的观测数据集对三种代表性暗能量模型进行全面联合分析—— ${\rm{\Lambda}CDM}$、Chevallier-Polarski-Linder（CPL）参数化以及广义涌现暗能量（GEDE）模型。这些观测数据集包括来自DESI数据发布1和2（DR1/DR2）的重子声波振荡（BAO）测量、Ia型超新星（SNe Ia）的Pantheon Plus样本以及TDCOSMO透镜的时间延迟宇宙学。CPL模型相对于 ${\rm{\Lambda}CDM}$ 显示出统计上的显著改进，在DESI DR2+Pantheon Plus+TDCOSMO中 $\Delta \chi^2 = -3.6$，倾向于类似于正则场的行为（$w_0=-0.87^{+0.05 }_{-0.05} $, $w_a=-0.41^{+ 0.28}_{-0.28}$，置信水平为1$\sigma$）。 GEDE模型也显示出比${\rm{\Lambda}CDM}$略微更优的拟合效果，并且与观测值一致，得到$\Delta \chi^2 =-2.83$（DR1）和$\Delta \chi^2 = -3.82$（DR2）。 GEDE模型中捕获的潜在暗能量演化转变参数$\Delta$被限制在$-0.52^{+0.22}_{-0.20}$（DR1）和$-0.50^{+0.18}_{-0.17}$（DR2），分别显示出相对于零的$2.4\sigma$和$2.9\sigma$偏离。 这个具有统计显著性（$>2\sigma$）的非零值$\Delta$提供了反对纯宇宙常数情景的证据。 负号表明在晚期宇宙中具有类似五重态的行为（$w > -1$）。值得注意的是，GEDE约束显示出与（现象学涌现暗能量模型）预测的$>3\sigma$紧张关系（$\Delta=1$）。 这种显著的差异意味着，尽管这两种模型都属于涌现暗能量家族，但它们截然不同的转变机制导致了不同的宇宙学意义。 我们的研究结果共同表明，GEDE为$\Lambda$冷暗物质提供了现象学上可行的替代方案。 显示英文摘要

摘要： In this work, we perform a comprehensive joint analysis of three representative dark energy models - ${\rm{\Lambda}CDM}$, the Chevallier-Polarski-Linder (CPL) parametrization, and the Generalised Emergent Dark Energy (GEDE) model - using the latest observational datasets: baryon acoustic oscillation (BAO) measurements from DESI Data Releases 1 and 2 (DR1/DR2), the Pantheon Plus sample of Type Ia supernovae (SNe Ia), and time-delay cosmography from TDCOSMO lensing. The CPL model yields a statistically significant improvement over ${\rm{\Lambda}CDM}$, with $\Delta \chi^2 = -3.6$ for DESI DR2+Pantheon Plus+TDCOSMO, favoring a quintessence-like behavior ($w_0=-0.87^{+0.05 }_{-0.05} $, $w_a=-0.41^{+ 0.28}_{-0.28}$ at 1$\sigma$ confidence level). The GEDE model also exhibits slightly favoring than ${\rm{\Lambda}CDM}$ with observations, yielding $\Delta \chi^2 =-2.83$ (DR1) and $\Delta \chi^2 = -3.82$ (DR2). The captured potential dark energy evolution transition parameter $\Delta$ in GEDE model is constrained to $-0.52^{+0.22}_{-0.20}$ (DR1) and $-0.50^{+0.18}_{-0.17}$ (DR2), showing a $2.4\sigma$ and $2.9\sigma$ deviation from zero respectively. This statistically significant ($>2\sigma$) non-zero value of $\Delta$ provides evidence against a pure cosmological constant scenario. The negative sign indicates quintessence-like behavior ($w > -1$) in the late universe. Notably, the GEDE constraints show a $>3\sigma$ tension with the $\Delta=1$ (Phenomenological Emergent Dark Energy model) predictions. This significant discrepancy implies that while both models belong to the emergent dark energy family, their fundamentally different transition mechanisms lead to distinct cosmological implications. Our results collectively suggest that GEDE provides a phenomenologically viable alternative to $\Lambda$CDM.