Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black Holes
We review the models unifying inflation and Primordial Black Hole (PBH) formation, which are based on the modified (Starobinsky-type) supergravity. We begin with the basic (Starobinsky) inflationary model of modified gravity and its alpha-attractor-type generalizations for PBH production, and recall...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-04-01
|
| Series: | Universe |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2218-1997/7/5/115 |
| _version_ | 1797536889767460864 |
|---|---|
| author | Sergei V. Ketov |
| author_facet | Sergei V. Ketov |
| author_sort | Sergei V. Ketov |
| collection | DOAJ |
| description | We review the models unifying inflation and Primordial Black Hole (PBH) formation, which are based on the modified (Starobinsky-type) supergravity. We begin with the basic (Starobinsky) inflationary model of modified gravity and its alpha-attractor-type generalizations for PBH production, and recall how all those single-field models can be embedded into the minimal supergravity. Then, we focus on the effective two-field models arising from the modified (Starobinsky-type) supergravity and compare them to the single-field models under review. Those two-field models describe double inflation whose first stage is driven by Starobinsky’s scalaron and whose second stage is driven by another scalar belonging to the supergravity multiplet. The power spectra are numerically computed, and it is found that the ultra-slow-roll regime gives rise to the enhancement (peak) in the scalar power spectrum leading to an efficient PBH formation. The resulting PBH masses and their density fraction (as part of dark matter) are found to be in agreement with cosmological observations. The PBH-induced gravitational waves, if any, are shown to be detectable by the ground-based and space-based gravitational interferometers under construction. |
| first_indexed | 2024-03-10T12:07:16Z |
| format | Article |
| id | doaj.art-007932c894d54d2cace4790097411516 |
| institution | Directory Open Access Journal |
| issn | 2218-1997 |
| language | English |
| last_indexed | 2024-03-10T12:07:16Z |
| publishDate | 2021-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Universe |
| spelling | doaj.art-007932c894d54d2cace47900974115162023-11-21T16:29:19ZengMDPI AGUniverse2218-19972021-04-017511510.3390/universe7050115Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black HolesSergei V. Ketov0Department of Physics, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji-Shi, Tokyo 192-0397, JapanWe review the models unifying inflation and Primordial Black Hole (PBH) formation, which are based on the modified (Starobinsky-type) supergravity. We begin with the basic (Starobinsky) inflationary model of modified gravity and its alpha-attractor-type generalizations for PBH production, and recall how all those single-field models can be embedded into the minimal supergravity. Then, we focus on the effective two-field models arising from the modified (Starobinsky-type) supergravity and compare them to the single-field models under review. Those two-field models describe double inflation whose first stage is driven by Starobinsky’s scalaron and whose second stage is driven by another scalar belonging to the supergravity multiplet. The power spectra are numerically computed, and it is found that the ultra-slow-roll regime gives rise to the enhancement (peak) in the scalar power spectrum leading to an efficient PBH formation. The resulting PBH masses and their density fraction (as part of dark matter) are found to be in agreement with cosmological observations. The PBH-induced gravitational waves, if any, are shown to be detectable by the ground-based and space-based gravitational interferometers under construction.https://www.mdpi.com/2218-1997/7/5/115inflationprimordial black holessupergravitydark matter |
| spellingShingle | Sergei V. Ketov Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black Holes Universe inflation primordial black holes supergravity dark matter |
| title | Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black Holes |
| title_full | Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black Holes |
| title_fullStr | Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black Holes |
| title_full_unstemmed | Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black Holes |
| title_short | Multi-Field versus Single-Field in the Supergravity Models of Inflation and Primordial Black Holes |
| title_sort | multi field versus single field in the supergravity models of inflation and primordial black holes |
| topic | inflation primordial black holes supergravity dark matter |
| url | https://www.mdpi.com/2218-1997/7/5/115 |
| work_keys_str_mv | AT sergeivketov multifieldversussinglefieldinthesupergravitymodelsofinflationandprimordialblackholes |