Автор |
Katherine J. Mack |
Дата выпуска |
2011-07-01 |
dc.description |
The QCD axion is the leading solution to the strong-CP problem, a dark matter candidate, and a possible result of string theory compactifications. However, for axions produced before inflation, symmetry-breaking scales of f<sub>a</sub>≳10<sup>12</sup> GeV (which are favored in string-theoretic axion models) are ruled out by cosmological constraints unless both the axion misalignment angle θ<sub>0</sub> and the inflationary Hubble scale H<sub>I</sub> are extremely fine-tuned. We show that attempting to accommodate a high-f<sub>a</sub> axion in inflationary cosmology leads to a fine-tuning problem that is worse than the strong-CP problem the axion was originally invented to solve. We also show that this problem remains unresolved by anthropic selection arguments commonly applied to the high-f<sub>a</sub> axion scenario. |
Формат |
application.pdf |
Издатель |
Institute of Physics Publishing |
Название |
Axions, inflation and the anthropic principle |
Тип |
paper |
DOI |
10.1088/1475-7516/2011/07/021 |
Electronic ISSN |
1475-7516 |
Журнал |
Journal of Cosmology and Astroparticle Physics |
Том |
2011 |
Первая страница |
21 |
Последняя страница |
021 |
Аффилиация |
Katherine J. Mack; Kavli Institute for Cosmology, Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, U.K. |
Выпуск |
07 |