Modified gravity spins up galactic halos

Lee, J.; Zhao, G.; Li, B.; Koyama, K.

Abstract

We investigate the effect of modified gravity on the specific angular momentum of galactic halos by analyzing the halo catalogs at z = 0 from high-resolution N-body simulations for a f(R) gravity model that meets the solar-system constraint. It is shown that the galactic halos in the f(R) gravity model tend to acquire significantly higher specific angular momentum than those in the standard ΛCDM model. The largest difference in the specific angular momentum distribution between these two models occurs for the case of isolated galactic halos with mass less than 1011 h –1 M ☉, which are likely least shielded by the chameleon screening mechanism. As the specific angular momentum of galactic halos is rather insensitive to other cosmological parameters, it can in principle be an independent discriminator of modified gravity. We speculate a possibility of using the relative abundance of low surface brightness galaxies (LSBGs) as a test of general relativity given that the formation of the LSBGs occurs in fast spinning dark halos.

Citation

Lee, J., Zhao, G., Li, B., & Koyama, K. (2013). Modified gravity spins up galactic halos. Astrophysical Journal, 763(1), Article 28. https://doi.org/10.1088/0004-637x/763/1/28

• Journal Article Type: Article
• Publication Date: Jan 20, 2013
• Deposit Date: Mar 27, 2013
• Publicly Available Date: May 2, 2014
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 763
• Issue: 1
• Article Number: 28
• DOI: https://doi.org/10.1088/0004-637x/763/1/28
• Keywords: Cosmology: theory, Large-scale structure of Universe, Methods: statistical.