Equivalence between generalized phenomenological schemes for the interaction of cosmological fluids: applications to arbitrary linear barotropic fluids and vacuum decay
宇宙流体之间的相互作用可能出现在许多宇宙学场景中，远远超出了通常研究的暗区能量交换。在缺乏已知的微观相互作用机制的情况下，通常提出唯象ansatzes来描述这样的模型。在本文中，我们得到了最常用的一个这样的ansatzes的推广：一个基于Shapiro，Solà，España-Bonet和Ruiz-Lapuente的最初建议，他们描述了一个依赖于时间的宇宙学“常数”，其变化来自普朗克尺度附近的量子效应[I]。L. Shapiro，J. Solà，C. España-Bonet，and P. Ruiz-Lapuente，（2003）.这个物理驱动的模型基于一个单一的自由参数$ν$，随后由Wang和Meng（2005）在纯唯象推理下进行了研究，即真空衰变会稍微修改描述暗物质的能量密度如何随标度因子下降的指数。该修改由单个参数$\varepsilon$（=前一篇论文的3个$ν$）描述。本文中导出的泛化需要两个自由参数（$\varepsilon_{1}$，$\varepsilon_{2}$）。我们表明，这种扩展是动态等效的Anonymous提出的巴罗和克利夫顿（2006年），处理任何两种流体之间的能量转移使用两个参数的计划（$α_{1}$，$α_{2}$），并具有明确的表现形式的相互作用因子出现在每种流体的连续性方程的优势。
英文摘要：
Interactions between cosmic fluids may appear in many cosmological scenarios that go far beyond the usually studied energy exchange in the dark sector. In the absence of known microscopic interaction mechanisms, phenomenological ansatzes are usually proposed in order to describe such models. In this paper, we derive a generalization of one of the most frequently used of such ansatzes:the one based on a initial proposal of Shapiro, Solà, España-Bonet and Ruiz-Lapuente who described a time-dependent cosmological "constant" whose variation arises from quantum effects near the Planck scale [I. L. Shapiro, J. Solà, C. España-Bonet, and P. Ruiz-Lapuente, (2003). This physically motivated model was based on a single free parameter $ν$, and was subsequently studied by Wang and Meng (2005), under the pure phenomenological reasoning that the vacuum decay would slightly modify the exponent describing how the energy density of dark matter decreases with the scale factor. This modification is described by a single parameter $\varepsilon$ (= 3 $ν$ of the former paper). The generalization derived in the present article requires two free parameters ($\varepsilon_{1}$, $\varepsilon_{2}$). We show that this extension is dynamically equivalent to the ansatz proposed by Barrow and Clifton (2006) which deals with the transfer of energy between any two fluids using a two-parameter scheme ($α_{1}$, $α_{2}$) and that has the advantage of exhibiting explicitly the form of the interaction factor appearing in the continuity equation of each fluid.
A Spectrum of Cosmological Rips and Their Observational Signatures
University of the Basque Country UPV/EHU（巴斯克大学）；EHU Quantum Center, University of the Basque Country UPV/EHU（EHU量子中心，巴斯克大学）；Institute of Physics, University of Szczecin（谢切钦大学物理研究所）
