On Dark Matter Self-Interactions from Higher Dimensional Gravity

Abstract

It has recently been suggested that in a brane world scenario with large extra dimensions, short distance gravitational interactions can enhance the dark matter scattering cross-section in a velocity dependent way. Such a modification may then help to address possible problems with non-interacting cold dark matter on galactic and sub-galactic scales. We argue that, considering the singular character of the higher dimensional Newtonian potential, the scattering cross-section is UV-dependent, depending ultimately on the underlying quantum gravity theory considered. We demonstrate that for a wide class of unitary short distance regularizations, the actual cross-section is velocity-independent and does not significantly affect dark matter substructure. We comment on the problem of thermalization of ultra-light cold dark matter by gravitational interactions in the early universe.

5 pages, revtex 4. References and comments on thermalization in the early universe added

References in corpus (18)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• A Universal Density Profile from Hierarchical Clustering
• A Large Mass Hierarchy from a Small Extra Dimension
• An Alternative to Compactification
• The Hierarchy Problem and New Dimensions at a Millimeter
• New Dimensions at a Millimeter to a Fermi and Superstrings at a TeV
• Phenomenology, Astrophysics and Cosmology of Theories with Sub-Millimeter Dimensions and TeV Scale Quantum Gravity
• Observational and Theoretical Constraints on Singular Dark Matter Halos
• Quantum Gravity and Extra Dimensions at High-Energy Colliders
• On Kaluza-Klein States from Large Extra Dimensions
• The cored distribution of dark matter in spiral galaxies
• The dark and baryonic matter content of low surface brightness disk galaxies
• Constraints on the Structure of Dark Matter Halos from the Rotation Curves of Low Surface Brightness Galaxies
• A Dynamical Fossil in the Ursa Minor Dwarf Spheroidal Galaxy
• Evidence of self-interacting cold dark matter from galactic to galaxy cluster scales
• Bars and Dark Matter Halo Cores
• The Distribution of Dark Matter in Galaxies: a Constant-Density Halo around DDO 47
• The Dark Halo of NGC 5963 as a Constraint on Dark Matter Self-Interaction at the Low Velocity Regime

Cited by in corpus (1)

• Enhanced gravitational scattering from large extra dimensions