Probing a QCD string axion with precision cosmological measurements

By P. Fox, A. Pierce, S. Thomas. 2004

134 citations recorded by the source corpus.

String and M-theory compactifications generically have compact moduli which can potentially act as the QCD axion. However, as demonstrated here, such a compact modulus can not play the role of a QCD axion and solve the strong CP problem if gravitational waves interpreted as arising from inflation with Hubble constant H{sub inf} {approx}> 10{sup 13} GeV are observed by the PLANCK polarimetry experiment. In this case axion fluctuations generated during inflation would leave a measurable isocurvature and/or non-Gaussian imprint in the spectrum of primordial temperature fluctuations. This conclusion is independent of any assumptions about the initial axion misalignment angle, how much of the dark matter is relic axions, or possible entropy release by a late decaying particle such as the saxion; it relies only on the mild assumption that the Peccei-Quinn symmetry remains unbroken in the early universe.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/daed0d75e2fed4f98c524f4c973f206df5641454

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. P. Graham
2. J. Mardon
3. Glenn Wouda
4. Luca Visinelli
5. S. Watson
6. L. Luzio
7. Bobby Samir Acharya
8. E. Nardi

In Nuclear and High Energy Physics

1. P. Graham
2. S. Rajendran
3. J. Mardon
4. Luca Visinelli
5. E. Nardi
6. L. Luzio
7. Maurizio Giannotti
8. Glenn Wouda

Citations in the corpus

• The landscape of QCD axion models (2020, background): “[728].”
• The dark-matter axion mass (2017, background): “ reasonably guess that m<f a’2 1011 GeV. Also the requirement that the radial excitations decay by the time the Universe reaches a temperature of 1 GeV, along with an estimate for their decay rate [45], m˘ 2 s 64ˇ3 m3 f2 a , sets very roughly m>103 GeV. These limits correspond to approximately”
• An M theory solution to the strong CP-problem, and constraints on the axiverse (2010, methodology): “We then generalize the analysis of [ 2 ] for the QCD axion to a situation with many axions roughly distributed evenly on a logarithmic scale.”
• The Strong CP problem and axions (2006, result): “I quote the result of a recent calculation by Fox, Pierce and Thomas [ 42 ] of the contribution to the Universe’s energy density due to axions:”
• Vector Dark Matter from Inflationary Fluctuations (2015, background): “This rules out this production mechanism for these dark matter candidates, instead leading to constraints on such scenarios in simple models [9].”
• Cosmological Moduli and the Post-Inflationary Universe: A Critical Review (2015, methodology): “where ξosc ≡ ma(Tosc)/ma(0) is the ratio of the finite temperature mass to the zero temperature mass and is typically an order one number [112].”