标题： 标量宇宙学中解决视界问题的幻影场必要性 显示英文标题

标题： On the necessity of phantom fields for solving the horizon problem in scalar cosmologies

摘要： 我们讨论了在空间均匀且各向同性的标量宇宙学框架下的粒子视界问题。为此，我们考虑了一个可能具有非零空间截面曲率（且任意维度）的弗里德曼-勒梅特-罗伯逊-沃克（FLRW）时空，并假设宇宙的内容是一组完美流体，加上一个既可以是 quintessence 也可以是 phantom 的标量场（取决于其作用量动能部分的符号）。我们证明，如果该场是 quintessence，空间曲率为非正且完美流体满足通常的能量条件，则粒子视界的出现不可避免。作为部分逆命题，我们给出了三个可解模型，在这些模型中，除了完美流体外还存在 phantom，并且没有粒子视界出现。 显示英文摘要

摘要： We discuss the particle horizon problem in the framework of spatially homogeneous and isotropic scalar cosmologies. To this purpose we consider a Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime with possibly non-zero spatial sectional curvature (and arbitrary dimension), and assume that the content of the universe is a family of perfect fluids, plus a scalar field that can be a quintessence or a phantom (depending on the sign of the kinetic part in its action functional). We show that the occurrence of a particle horizon is unavoidable if the field is a quintessence, the spatial curvature is non-positive and the usual energy conditions are fulfilled by the perfect fluids. As a partial converse, we present three solvable models where a phantom is present in addition to a perfect fluid, and no particle horizon~appears.