The formation of primordial black holes in the early universe may happen through the collapse of large curvature perturbations generated during a non-attractor phase of inflation or through a curvaton-like dynamics after inflation. The fact that such small-scale curvature perturbation is typically non-Gaussian leads to the renormalization of composite operators built up from the smoothed density contrast and entering in the calculation of the primordial black abundance. Such renormalization causes the phenomenon of operator mixing and the appearance of an infinite tower of local, non-local and higher-derivative operators as well as to a sizable shift in the threshold for primordial black hole formation. This hints that the calculation of the primordial black hole abundance is more involved than what generally assumed. We show the impact of this phenomenon in a perturbatively non-gaussian scenario, giving also an estimate of its effect on the threshold for primordial black hole formation.

中文翻译：

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重整化原始黑洞


早期宇宙中原始黑洞的形成可能是通过在膨胀的非吸引子阶段产生的大曲率扰动的坍缩或通过膨胀后的曲率动力学发生的。这种小尺度曲率扰动通常是非高斯的，这一事实导致从平滑密度对比构建的复合算子的重新归一化，并进入原始黑色丰度的计算。这种重整化导致了算子混合现象和局部、非局部和高导数算子的无限塔的出现，以及原始黑洞形成阈值的相当大的变化。这表明原始黑洞丰度的计算比通常假设的要复杂得多。我们展示了这种现象在扰动非高斯情景下的影响，还估计了它对原始黑洞形成阈值的影响。