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Dynamics of Topological Defects and Inflation

Nobuyuki Sakai·Hisa-aki Shinkai·Takashi Tachizawa·Kei-ichi Maeda
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Abstract

We study the dynamics of topological defects in the context of ``topological inflation" proposed by Vilenkin and Linde independently. Analysing the time evolution of planar domain walls and of global monopoles, we find that the defects undergo inflationary expansion if $η\stackrel{>}{\sim}0.33m_{Pl}$, where $η$ is the vacuum expectation value of the Higgs field and $m_{Pl}$ is the Planck mass. This result confirms the estimates by Vilenkin and Linde. The critical value of $η$ is independent of the coupling constant $λ$ and the initial size of the defect. Even for defects with an initial size much greater than the horizon scale, inflation does not occur at all if $η$ is smaller than the critical value. We also examine the effect of gauge fields for static monopole solutions and find that the spacetime with a gauge monopole has an attractive nature, contrary to the spacetime with a global monopole. It suggests that gauge fields affect the onset of inflation.

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Nobuyuki Sakai, Hisa-aki Shinkai, Takashi Tachizawa, Kei-ichi Maeda. 1995-10-23. Dynamics of Topological Defects and Inflation. https://doi.org/10.1103/physrevd.53.655%2010.1103%2Fphysrevd.54.2981

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