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arXiv · 1107.1681

Primordial black hole formation and hybrid inflation

David H. Lyth
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Abstract

We calculate the contribution to the curvature perturbation, that is generated while the waterfall field grows exponentially (which can occur only if the waterfall field mass is $m\gg H$). We consider the upper bound on its spectrum coming from constraints on the abundance of primordial black holes, taking account of possible non-gaussianity. The constraint is satisfied, but extrapolation of our result to the regime $m\sim H$ suggests that the constraint might not be satisfied there.

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David H. Lyth. 2011-07-08. Primordial black hole formation and hybrid inflation. https://arxiv.org/abs/1107.1681

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