Primordial black hole dark matter from single field inflation

By G. Ballesteros, M. Taoso. 2017

286 citations recorded by the source corpus.

We propose a model of inflation capable of generating a population of light black holes (about 10-16–10-14 solar masses) that might account for a significant fraction of the dark matter in the Universe. The effective potential of the model features an approximate inflection point arising from two-loop order logarithmic corrections in well-motivated and perturbative particle physics examples. This feature decelerates the inflaton before the end of inflation, enhancing the primordial spectrum of scalar fluctuations and triggering efficient black hole production with a peaked mass distribution. At larger field values, inflation occurs thanks to a generic small coupling between the inflaton and the curvature of spacetime. We compute accurately the peak mass and abundance of the primordial black holes using the Press-Schechter and Mukhanov-Sasaki formalisms, showing that the slow-roll approximation fails to reproduce the correct results by orders of magnitude. We study as well a qualitatively similar implementation of the idea, where the approximate inflection point is due to competing terms in a generic polynomial potential. In both models, requiring a significant part of the dark matter abundance to be in the form of black holes implies a small blue scalar tilt with a sizable negative running and a tensor spectrum that may be detected by the next-generation probes of the cosmic microwave background. We also comment on previous works on the topic.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/265e201df351fff9625fb6d39697878d602a811f

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. A. Starobinsky
2. V. Sahni
3. A. Kehagias
4. A. Riotto
5. G. Franciolini
6. F. Pedro
7. V. A. Diaz
8. G. Tringas

In Nuclear and High Energy Physics

1. A. Kehagias
2. A. Starobinsky
3. V. Sahni
4. F. Pedro
5. V. A. Diaz
6. G. Tringas
7. I. Dalianis
8. A. Riotto

Citations in the corpus

• Primordial Black Holes from Polynomial Potentials in Single Field Inflation (2017, unknown): “In particular, we find that the slow-roll condition has to be violated [35–40] and we can achieve this by having the inflaton overshoot a local minimum during inflation [38, 40].”
• Generating PBHs and small-scale GWs in two-field models of inflation (2020, background): “This can be achieved in single-field inflation scenarios by using a local feature in the inflaton potential like a rapid change of its amplitude or a break in its first derivative [7–9], an inflection point [10–18] or a tiny bump superimposed on it [19, 20], non-trivial inflaton sound speed [21–23]1”
• Primordial black holes from inflation and quantum diffusion (2018, background): “One might naively think that during the non-attractor phase the noise is not relevant if φ′ is larger than (H/2π) [17].”
• Primordial black holes from string inflation (2018, background): “Moreover the single-field inflationary dynamics seems to be very unlikely to generate black holes with masses as large as a few solar masses when the scalar spectral index is required to be compatible with CMB data [2].”
• Primordial black holes from α-attractors (2018, background): “Critical Higgs inflation [20], simple polynomials or potentials with a radiative plateau a la Coleman-Weinberg where the inflaton is non-minimally coupled to the Ricci scalar [21, 22], fibre inflation [24] and axion models [25] inspired by string theory, supergravity [26] are examples of single fiel”
• Primordial black holes from a tiny bump/dip in the inflaton potential (2019, methodology): “The following criteria need to be satisfied so that an inflationary potential can generate fluctations which are large enough to seed PBH formation [38, 47, 49, 50].”