论文标题
探索来自普朗克质量变化的宇宙学常数的自我调整
Exploring the self-tuning of the cosmological constant from Planck mass variation
论文作者
论文摘要
最近，提出，普朗克质量在一般相对论的爱因斯坦 - 希尔伯特作用中的变化被认为是宇宙常数的自我调整机制，从而防止了标准模型真空能量自由地吸引并实现其观察到的价值的幅度。我们在这里探索该提案的新方面。我们首先将同等的爱因斯坦 - 框架形式主义与当前的约旦框架制定机制开发，并使用它来突出自我调整与隔离机制的相似性和差异。然后，我们展示了如何通过耦合的高斯式术语和伴侣四种场强的局部自我调整动作扩展，可以防止重力循环能够使标准模型真空能的脱盖失去能力。在某些情况下，我们此外发现，该扩展可以作为Horndeski标量调整理论重新铸造，并嵌入到传统的局部自我调整形式主义中。然后，我们探讨了自我调整统一通货膨胀的可能性。可以使用所得的方程式来激励多元宇宙解释。在这种情况下，我们重新审视巧合问题，并为宇宙中智能生命在宇宙时代的函数中出现的概率提供了估计，这是从星星和地面行星形成过程中推断出来的。我们得出的结论是，我们生活在一个非常典型的时代，我们应该期望宇宙常数和物质的能量密度相当。为了将无尺寸的数量比较在多宇宙的拟人分析中，在不同宇宙的宇宙历史中比较了生命的出现，我们选择了宇宙不断发展的地平线大小的数量级差异，即其质子的大小作为原子，分子和最终生命的基本质子构建块。 （简略）
Recently, the variation of the Planck mass in the General Relativistic Einstein-Hilbert action was proposed as a self-tuning mechanism of the cosmological constant, preventing Standard Model vacuum energy from freely gravitating and enabling an estimation of the magnitude of its observed value. We explore here new aspects of this proposal. We first develop an equivalent Einstein-frame formalism to the current Jordan-frame formulation of the mechanism and use this to highlight similarities and differences of self-tuning to the sequestering mechanism. We then show how with an extension of the local self-tuning action by a coupled Gauss-Bonnet term and a companion four-form field strength, graviton loops can be prevented from incapacitating the degravitation of the Standard Model vacuum energy. For certain cases, we furthermore find that this extension can be recast as a Horndeski scalar-tensor theory and be embedded in the conventional local self-tuning formalism. We then explore the possibility of a unification of inflation with self-tuning. The resulting equations can alternatively be used to motivate a multiverse interpretation. In this context, we revisit the coincidence problem and provide an estimation for the probability of the emergence of intelligent life in our Universe as a function of cosmic age, inferred from star and terrestrial planet formation processes. We conclude that we live at a very typical epoch, where we should expect the energy densities of the cosmological constant and matter to be of comparable size. For a dimensionless quantity to compare the emergence of life throughout the cosmic history of different universes in an anthropic analysis of the multiverse, we choose the order of magnitude difference of the evolving horizon size of a universe to the size of its proton as the basic building block of atoms, molecules, and eventually life. (abridged)
