Subhalo Abundance Matching in f(R) Gravity

Area of Science:

• Cosmology
• Astrophysics
• General Relativity

Background:

• Modified gravity theories, such as f(R) gravity, offer alternatives to the standard Lambda Cold Dark Matter (ΛCDM) model.
• Understanding galaxy clustering is crucial for probing the nature of gravity and dark matter on large scales.

Purpose of the Study:

• To present the first predictions for galaxy clustering within f(R) gravity using subhalo abundance matching.
• To compare galaxy clustering in f(R) gravity with the ΛCDM model and quantify deviations.

Main Methods:

• Utilized N-body simulations from Shi et al.
• Employed subhalo abundance matching to link dark matter halos to galaxies.
• Analyzed galaxy clustering for an f(R) model with f_{R0}=-10^{-6}.

Main Results:

• Galaxy clustering in f(R) gravity deviates significantly from ΛCDM, even when dark matter clustering is similar.
• Deviations can reach up to 40% for galaxy samples near L* density.
• These deviations are within the reach of future large-scale galaxy surveys.

Conclusions:

• Galaxy surveys offer a powerful tool to test general relativity on cosmological scales.
• f(R) gravity predictions for galaxy clustering provide a stringent test comparable to astrophysical observations.