Particle Acceleration in Kerr-(anti-) de Sitter Black Hole Backgrounds

Understand

Recently, Ban\~{a}dos, Silk and West (BSW) found that the center-of-mass energy of two colliding test particles in the neighborhood of an extreme Kerr black hole could be arbitrarily high when one particle has the critical angular momentum $L_\text{C}$.

• In their paper, they considered the black holes living in a Minkowski space-time with a zero cosmological constant.
• In this work, we study this process of particles in the backgrounds of the Kerr black holes living in a space-time with a nonzero cosmological constant.
• We find that for kerr black holes living in a space-time with a negative cosmological constant (Kerr-anti-de Sitter black holes), this process of particles could happen only if the Kerr-anti-de Sitter black hole is extreme and an additional fine tuning is satisfied; while for kerr black holes living in a space-time with a positive cosmological constant (Kerr-de Sitter black holes), this process of particles could happen no matter the Kerr-de Sitter black hole is extreme or not.