2023/12/30 by Kun-Hui Fan, Yun Soo Myung, Fan, Kun-Hui +5
Physics and Astronomy · #Cosmology and Gravitation Theories #Black Holes and Theoretical Physics #Astrophysical Phenomena and Observations
paper · pdf · doi:10.48550/arxiv.2401.00144
We investigate the tachyonic instability of Kerr-Newman (KN) black hole with a rotation parameter a in the Einstein-Chern-Simons-scalar theory coupled with a quadratic massive scalar field. This instability analysis corresponds to exploring the onset of spontaneous scalarization for KN black holes. First, we find no a-bound for α<0 case by considering (1+1)-dimensional analytical method. A direct numerical method is adopted to explore (2+1)-dimensional time evolution of a massive scalar perturbation with positive and negative α to obtain threshold curves numerically. We obtain threshold curves α\rm th(a) of tachyonic instability for positive α without any a-bounds. We expect to find the same threshold curves α\rm th(a) of tachyonic instability for negative α without any a-bound because its linearized scalar theory is invariant under the transformation of α→ -α and θ→ -θ. In addition, it is found that the scalar mass term suppresses tachyonic instability of KN black holes.