Probing the anisotropic distribution of baryon matter in the Universe using fast radio bursts

Understand

We propose that fast radio bursts (FRBs) can be used as the probes to constrain the possible anisotropic distribution of baryon matter in the Universe.

• Monte Carlo simulations show that, 400 (800) FRBs are enough to detect the anisotropy at 95\% (99\%) confidence level, if the dipole amplitude is at the order of magnitude 0.01.
• However, much more FRBs are required to tightly constrain the dipole direction.
• Even 1000 FRBs are far from enough to constrain the dipole direction within angular uncertainty $\Delta\theta<40^{\circ}$ at 95\% confidence level.