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arXiv · 1007.4881

N-z Relation and CMB Anisotropies in the Universe with an Oscillating Scalar Field Having a Null Field State

Koichi Hirano·Kiyoshi Kawabata·Zen Komiya·Hiroshi Bunya
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Abstract

We investigate whether or nor it is possible to find a scalar field model or models that are capable of explaining simultaneously the observed $N$-$z$ relation given by the 2dF Galaxy Redshift Survey, which still seems to exhibit a spatial periodicity of the galaxy distribution(the 'picket-fence structure'), and the CMB spectrum obtained by the WMAP experiments. It is found that both the observed size of the spatial periodicity and the amplitude of the 2dF $N$-$z$ relation can be fairly well fitted by the theoretical computations based on the scalar field models with $-20\le \xi\le -10$, and $140\le m_{\rm s} \le 160$, where $\xi$ is the gravitational coupling parameter, and $m_{\rm s}$ the normalized mass of the scalar field, respectively. To reproduce the CMB spectrum of the WMAP, we find that it is very crucial to have a null state of the scalar field in the early epochs of evolution of the universe.

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Koichi Hirano, Kiyoshi Kawabata, Zen Komiya, Hiroshi Bunya. 2010-07-28. N-z Relation and CMB Anisotropies in the Universe with an Oscillating Scalar Field Having a Null Field State. https://arxiv.org/abs/1007.4881

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