Retesting the no-hair theorem with GW150914

For a distorted black hole (BH), its ringdown waveform is a superposition of quasi-normal modes (QNMs). In general relativity (GR), the lower order QNM frequencies and damping rates can be well approximated by a polynomial of BH's dimensionless spin and overall scaled by BH's mass. That is to say, we can test the no-hair theorem of BH in GR model-independently by allowing not only an overall fractional deviation (as M. Isi et al. did) but also a set of fractional deviation for every coefficient. In the paper, we will apply the latter method to retest the no-hair theorem with GW150914 and probe hairs' behaviors if hairs exist. Eventually, we find the data favors GR.

Automated summary

In this paper, a new method is used to retest the no-hair theorem of black holes in the framework of general relativity. The behavior of black holes is probed using the data from GW150914, and the results support the predictions of general relativity.