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arXiv · 2211.14262

Hybrid $\alpha$-attractors, primordial black holes and gravitational wave backgrounds

Matteo Braglia·Andrei Linde·Renata Kallosh·Fabio Finelli
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Abstract

We investigate the two-stage inflation regime in the theory of hybrid cosmological $\alpha$-attractors. The spectrum of inflationary perturbations is compatible with the latest Planck/BICEP/Keck results, thanks to the attractor properties of the model. However, at smaller scales, it may have a very high peak of controllable width and position, leading to a copious production of primordial black holes (PBH) and generation of a stochastic background of gravitational waves (SGWB).

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Matteo Braglia, Andrei Linde, Renata Kallosh, Fabio Finelli. 2022-11-25. Hybrid $\alpha$-attractors, primordial black holes and gravitational wave backgrounds. https://doi.org/10.1088/1475-7516%2F2023%2F04%2F033

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