标题： DESI之后的物理暗能量与幻影暗能量：弯曲背景下的解冻 quintessence 显示英文标题

标题： Physical vs phantom dark energy after DESI: thawing quintessence in a curved background

摘要： 来自DESI的最新数据，结合其他数据，提供了暗能量动力学的中等证据，即$w\neq-1$。 在$w_0, w_a$对$w$的参数化中，在红移处存在向幻影穿越（$w<-1$）的偏好，即$z\sim0.5$。 在广义相对论中，幻影状态方程是不物理的。 因此，检查在其他具有与$w_0, w_a$参数化等效证据的物理自洽暗能量模型中是否存在幻影穿越是很重要的。 我们发现，基于参数演化和真实的标量场演化，具有非零宇宙曲率的淬火五重态也能在平坦背景下很好地拟合最近的数据，这与$w_0, w_a$相当。 尽管现实模型不允许$w<-1$，但参数化允许它。然而，即使我们允许$w<-1$，数据也不支持幻影能穿越。因此，幻影穿越是基于非物理模型的参数化所产生的伪影。 显示英文摘要

摘要： Recent data from DESI, in combination with other data, provide moderate evidence of dynamical dark energy, $w\neq-1$. In the $w_0, w_a$ parametrization of $w$, there is a preference for a phantom crossing, $w<-1$, at redshift $z\sim0.5$. In general relativity, the phantom equation of state is unphysical. Thus it is important to check whether phantom crossing is present in other physically self-consistent models of dark energy that have equivalent evidence to the $w_0, w_a$ parametrization. We find that thawing quintessence with nonzero cosmic curvature can fit the recent data as well as $w_0, w_a$ in a flat background, based on both parametric and realistic scalar field evolutions. Although the realistic model does not allow $w<-1$, the parametrizations do allow it. However even if we allow $w<-1$ the data do not enforce phantom crossing. Thus, the phantom crossing is an artifact of a parametrization that is not based on a physical model.