Spherical accretion onto non-singular and bounce spacetimes

We investigate spherical accretion onto non-singular spacetimes using analytic and semi-analytic techniques to reveal how regularity parameters reshape both Bondi and Novikov-Thorne accretion. First, we revisit steady, radial inflow onto a family of spherically symmetric regular black holes (RBHs): Hayward, Bardeen, Dymnikova, and Fan-Wang. By modeling the ambient medium as either a constant-pressure fluid or an exponential density profile, we derive the expressions for the sonic radius, mass accretion rate, and luminosity. We find that RBH geometries amplify the accretion rate compared to Schwarzschild geometries, and that RBHs achieve higher luminosities in the Novikov-Thorne thin-disk framework, independent of the chosen fluid model.