The First Three Seconds: a Review of Possible Expansion Histories of the Early Universe

Journal Article · 28 June 2020 · Open J.Astrophys.

DOI: https://doi.org/10.21105/astro.2006.16182 · OSTI ID:1638661

Allahverdi, Rouzbeh ^[1]; Amin, Mustafa A.  ^[2]; Berlin, Asher  ^[3]; Bernal, Nicolás  ^[4]; Byrnes, Christian T. ^[5]; Sten Delos, M. ^[6]; Erickcek, Adrienne L. ^[6]; Escudero, Miguel  ^[7]; Figueroa, Daniel G.  ^[8]; Freese, Katherine ^[9]; Harada, Tomohiro ^[10]; Hooper, Dan  ^[11]; Kaiser, David I.  ^[12]; Karwal, Tanvi ^[13]; Kohri, Kazunori  ^[14]; Krnjaic, Gordan  ^[15]; Lewicki, Marek  ^[16]; Lozanov, Kaloian D. ^[17]; Poulin, Vivian ^[18]; Sinha, Kuver  ^[19] ; Smith, Tristan L. ^[20]; Takahashi, Tomo ^[21]; Tenkanen, Tommi  ^[2]; Unwin, James ^[22]; Vaskonen, Ville  ^[23]; Watson, Scott  ^[24]

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1. New Mexico U.
2. Rice U.
3. New York U., CCPP
4. Antonio Narino U.
5. Sussex U.
6. North Carolina U.
7. King's Coll. London
8. Valencia U., IFIC
9. Texas U.; Stockholm U., OKC
10. Rikkyo U.
11. Fermilab; Chicago U., KICP; Chicago U., Astron. Astrophys. Ctr.
12. MIT, Cambridge, Dept. Phys.
13. Pennsylvania U.
14. KEK, Tsukuba; Tokyo U., IPMU
15. Fermilab
16. King's Coll. London; Warsaw U.
17. Garching, Max Planck Inst.
18. U. Montpellier 2, LUPM
19. Oklahoma U.
20. Swarthmore Coll.
21. Saga U., Japan
22. Illinois U., Chicago
23. King's Coll. London; NICPB, Tallinn
24. Syracuse U.

It is commonly assumed that the energy density of the Universe was dominated by radiation between reheating after inflation and the onset of matter domination 54,000 years later. While the abundance of light elements indicates that the Universe was radiation dominated during Big Bang Nucleosynthesis (BBN), there is scant evidence that the Universe was radiation dominated prior to BBN. It is therefore possible that the cosmological history was more complicated, with deviations from the standard radiation domination during the earliest epochs. Indeed, several interesting proposals regarding various topics such as the generation of dark matter, matter-antimatter asymmetry, gravitational waves, primordial black holes, or microhalos during a nonstandard expansion phase have been recently made. In this paper, we review various possible causes and consequences of deviations from radiation domination in the early Universe - taking place either before or after BBN - and the constraints on them, as they have been discussed in the literature during the recent years.

• Research Organization: Antonio Narino U.; Chicago U., Astron. Astrophys. Ctr.; Chicago U., KICP; Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Garching, Max Planck Inst.; Illinois U., Chicago; KEK, Tsukuba; King's Coll. London; MIT, Cambridge, Dept. Phys.; NICPB, Tallinn; New Mexico U.; New York U., CCPP; North Carolina U.; Oklahoma U.; Pennsylvania U.; Rice U.; Rikkyo U.; Saga U., Japan; Stockholm U., OKC; Sussex U.; Swarthmore Coll.; Syracuse U.; Texas U.; Tokyo U., IPMU; U. Montpellier 2, LUPM; Univ. of Michigan, Ann Arbor, MI (United States); Valencia U., IFIC; Warsaw U.
• Sponsoring Organization: US Department of Energy; USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-07CH11359; SC0007859
• OSTI ID: 1638661
• Report Number(s): FERMILAB-PUB-20-242-A; IPMU20-0070; KCL-PH-TH/2020-33; KEK-Cosmo-257, KEK-TH-2231; PI/UAN-2020-674FT; RUP-20-22; oai:inspirehep.net:1803656; arXiv:2006.16182
• Journal Information: Open J.Astrophys., Journal Name: Open J.Astrophys. Vol. 4
• Country of Publication: United States
• Language: English