Impact of the local void on the cosmological parameters
- Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)
In this paper, I discuss the effects of a local void on the cosmological parameters. It is found that, if the supernova distance is absolutely calibrated, then the bias of all the cosmological parameters is always important, while if the supernova distance is relatively calibrated, the largest effects will appear in the dark energy equation of state. For a local void of size ∼ 100 Mpc, the bias effects mainly manifest in the low redshift range. Therefore, the piecewise dark energy equation of state, especially the one in the range of lowest redshift, will be more strongly affected than the constant equation of state. In order to reduce this bias in constraining the cosmological parameters, one could require the distance of all the adopted supernovas be greater than 1.2 ∼ 1.5 times of the radius of the local void. In this case, the residual bias can be safely ignored.
- OSTI ID:
- 22282951
- Journal Information:
- Journal of Cosmology and Astroparticle Physics, Vol. 2013, Issue 03; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
- Country of Publication:
- United States
- Language:
- English
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