Domain wall signatures in BICEP2, Planck, VLT/UVES and Keck/HIRES data?
Year: 2014
Type: preprint
Abstract: We consider the possibility that current hints for a spatial variation of the fine structure constant at high redshift could be due to a domain wall network described by a scalar field non-minimally coupled to the electromagnetic field. We show that in order to be cause of the reported spatial variation of the fine structure constant, without being in conflict with the observed anisotropies of the cosmic microwave background, the characteristic scale of the network would have to be of the order of the Hubble radius and the fractional contribution of the domain wall network to the energy density of the Universe would need to be in the range $10^{-10} < \Omega_{w0} < 10^{-5}$. We argue that for sufficiently large values of $\Omega_{w0}$ in this range, domain walls could even be responsible for the large scale anomalies in the temperature distribution of the cosmic microwave background detected by Planck and WMAP and for the B-mode polarisation signature detected by BICEP2. Since the domain wall contribution to the cosmic energy budget only becomes important at late times, domain wall networks cannot play a significant role as a seed for large scale structure formation and primary cosmic microwave background anisotropies.
Source: arXiv (Cornell University)
Authors: P. P. Avelino, L. Sousa
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W1541803476