Baryon-to-dark matter ratio from random angular fields
- Lancaster-Manchester-Sheffield Consortium for Fundamental Physics, Cosmology and Astroparticle Physics Group, Dept. of Physics, University of Lancaster, Lancaster LA1 4YB (United Kingdom)
We consider the baryon-to-dark matter ratio in models where the dark matter and baryon densities depend on angular fields θ{sub d} and θ{sub b} according to ρ{sub d}∝θ{sub d}{sup α} and ρ{sub b}∝θ{sub b}{sup β}, with all values of θ{sub d} and θ{sub b} being equally probable in a given randomly-selected domain. Under the assumption that anthropic selection depends primarily on the baryon density in galaxies at spherical collapse, we show that the probability density function for the baryon-to-dark matter ratio r = Ω{sub B}/Ω{sub DM} is purely statistical in nature and is independent of anthropic selection. We compute the probability density function for r as a function of α and β and show that the observed value of the baryon-to-dark matter ratio, r ≈ 1/5, is natural in this framework.
- OSTI ID:
- 22279617
- Journal Information:
- Journal of Cosmology and Astroparticle Physics, Vol. 2013, Issue 01; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
- Country of Publication:
- United States
- Language:
- English
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