2025/04/24 by Sanzeni, Giulio, Mosani, Karim
#Differential Geometry (math.DG) #FOS: Mathematics #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc)
paper · doi:10.48550/arxiv.2504.17763
The analytic extension of the Kerr spacetimes into the negative radial region contains closed causal curves for any non-zero rotation parameter a and mass parameter M. Furthermore, the spacetimes become totally vicious when |a|>M, meaning that through every point there exists a closed timelike curve. Despite this, we prove that the Kerr spacetimes do not admit any closed null geodesics when |a|≥ M. This result generalises recent findings by one of the authors, which showed the nonexistence of closed causal geodesics in the case |a|