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arXiv · 0901.0429

Timelike Vector Field Dynamics in the Early Universe

Seoktae Koh·Bin Hu
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Abstract

We study the dynamics of a timelike vector field which violates Lorentz invariance when the background spacetime is in an accelerating phase in the early universe. It is shown that a timelike vector field is difficult to realize an inflationary phase, so we investigate the evolution of a vector field within a scalar field driven inflation model. And we calculate the power spectrum of the vector field without considering the metric perturbations. While the time component of the vector field perturbations provides a scale invariant spectrum when $\xi = 0$, where $\xi$ is a nonminimal coupling parameter, both the longitudinal and transverse perturbations give a scale invariant spectrum when $\xi = 1/6$.

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Seoktae Koh, Bin Hu. 2009-01-05. Timelike Vector Field Dynamics in the Early Universe. https://doi.org/10.3938/jkps.60.1983

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