Year: 2001
Type: article
Abstract: We investigate the cosmological evolution of global monopoles in the radiation dominated (RD) and matter dominated (MD) universes by numerically solving field equations of scalar fields. It is shown that the global monopole network relaxes into the scaling regime, unlike the gauge monopole network. The number density of global monopoles is given by $n(t)\ensuremath{\simeq}(0.43\ifmmode\pm\else\textpm\fi{}{0.07)/t}^{3}$ during the RD era and $n(t)\ensuremath{\simeq}(0.25\ifmmode\pm\else\textpm\fi{}{0.05)/t}^{3}$ during the MD era. Thus, we have confirmed that density fluctuations produced by global monopoles become scale invariant and are given by $\ensuremath{\delta}\ensuremath{\rho}\ensuremath{\sim}7.2(5.0){\ensuremath{\sigma}}^{2}{/t}^{2}$ during the RD (MD) era, where $\ensuremath{\sigma}$ is the breaking scale of the symmetry.
Author: Masahide Yamaguchi
Institution: The University of Tokyo
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2065037254