论文标题
单场通货膨胀中的度量预热和辐射衰减
Metric preheating and radiative decay in single-field inflation
论文作者
论文摘要
通货膨胀结束时，充气量在其潜力的底部振荡，这些振荡引发了参数不稳定，对于不稳定带$（3h m）^{ - 1/2} <λ<λ<λ<h^{ - 1} $的不稳定频段$（3H m）^{ - 1/1/2} $ h $ h $ at y hubble parame cul cul的不稳定波长$λ$的参数不稳定。这种“度量预热”的不稳定性在狭窄的共鸣状态下进行，导致各种有趣的现象，例如早期结构形成，引力波的产生以及原始黑洞的形成。在这项工作中，我们在与其他自由度的相互作用的情况下研究其命运，并以扰动衰变的形式成为完美的液体。确实，为了确保从通货膨胀到辐射主导的时代的完全过渡，必须考虑度量预热以及扰动加热。我们发现，直到流体主导宇宙含量之前，充气的衰变不会改变不稳定性结构。作为应用程序，我们讨论了从不稳定性产生原始黑洞的产生的影响。我们强调标量场和完美的流体波动之间的差异，并解释了为什么不能使用有关完美流体不均匀性的原始黑洞的常规结果，从而阐明了文献中的一些最新陈述。
At the end of inflation, the inflaton oscillates at the bottom of its potential and these oscillations trigger a parametric instability for scalar fluctuations with wavelength $λ$ comprised in the instability band $(3H m)^{-1/2} <λ< H^{-1}$, where $H$ is the Hubble parameter and $m$ the curvature of the potential at its minimum. This "metric preheating" instability, which proceeds in the narrow resonance regime, leads to various interesting phenomena such as early structure formation, production of gravitational waves and formation of primordial black holes. In this work we study its fate in the presence of interactions with additional degrees of freedom, in the form of perturbative decay of the inflaton into a perfect fluid. Indeed, in order to ensure a complete transition from inflation to the radiation-dominated era, metric preheating must be considered together with perturbative reheating. We find that the decay of the inflaton does not alter the instability structure until the fluid dominates the universe content. As an application, we discuss the impact of the inflaton decay on the production of primordial black holes from the instability. We stress the difference between scalar field and perfect fluid fluctuations and explain why usual results concerning the formation of primordial black holes from perfect fluid inhomogeneities cannot be used, clarifying some recent statements made in the literature.
