3 papers
gr-qc2026
When does a sphere fall like a point particle? Quadrupole universality and Weyl-driven hexadecapole deviations in vacuum general relativity
Tiago S. Amancio, Ricardo A. Mosna, Ronaldo S. S. Vieira
We ask when a spinless spherical extended test body in vacuum general relativity moves as its point-particle counterpart. In Newtonian gravity, harmonicity of the external potentia…
gr-qc2024
Chaotic orbital dynamics of pulsating stars around black holes surrounded by dark matter halos
Tiago S. Amancio, Ricardo A. Mosna, Ronaldo S. S. Vieira
We analyze the orbital dynamics of spherical test bodies in ``black hole surrounded by dark matter halo'' spherically symmetric spacetimes. When the test body pulsates periodically…
gr-qc2024
Chaotic dynamics of pulsating spheres orbiting black holes
Fernanda de F. Rodrigues, Ricardo A. Mosna, Ronaldo S. S. Vieira
We study the chaotic dynamics of spinless extended bodies in a wide class of spherically symmetric spacetimes, which encompasses black-hole scenarios in many modified theories of g…