Axions in the Universe

This fully funded project is dedicated to axions and axion-like particles and their role in cosmology and astrophysics. Axions are very popular hypothesized pseudo-scalar particles with a number of attractive properties for particle physics, astrophysics and cosmology, for review see [1,2,3]. Axions originated from studies of quantum chromodynamics (QCD) to solve the notorious strong CP problem. One of the defining features of axions is that their mass and the low-energy interactions are suppressed by requirements of classical shift-symmetry. In this project we will investigate axion gravitational couplings, see e.g. [6] and their influence on black holes and other compact objects like in [3,4,5], on features of axion inflation and alternatives to inflation. We will also investigate axions as dark matter focusing on their production mechanisms.

This project involves broad international collaboration with France, Japan, South Korea and the USA.

References:

[1] Jihn E. Kim, G. Carosi, Axions and the Strong CP Problem, Rev.Mod.Phys. 82 (2010) 557–602, • e-Print: 0807.3125
[2] Jihn E. Kim, Light Pseudoscalars, Particle Physics and Cosmology, Phys.Rept. 150 (1987) 1–177
[3] A. Arvanitaki, S. Dimopoulos, S. Dubovsky, N. Kaloper, J. March-Russell, String Axiverse, Phys.Rev.D 81 (2010) 123530 • e-Print: 0905.4720 [hep-th]
[4] A. Arvanitaki, S. Dubovsky, Exploring the String Axiverse with Precision Black Hole Physics Phys.Rev.D 83 (2011) 044026 • e-Print: 1004.3558 [hep-th]
[5] D. Doneva, F. Ramazanoğlu, H.Silva, T. Sotiriou, S. Yazadjiev, Scalarization, e-Print: 2211.01766 [gr-qc]
[6] R. Kallosh, A. Linde, D. Linde, L. Susskind, Gravity and global symmetries, Phys.Rev.D 52 (1995) 912–935 • e-Print: hep-th/9502069 [hep-th]