A sphere or a disk? Accretion of gas onto isolated stellar-mass black holes

The most crucial problem in constructing a coherent model of the universe is the behavior of spacetime in the vicinity of the event horizons of black holes (BH). These regions can be accessible to direct observations only at low rates of spherical accretion. Based on the analysis of the current characteristics of interstellar gas turbulence, it has been shown that the spherical mode of accretion, unlike the disk mode, occurs at sufficiently low densities of the medium (excluding clouds and ``hot'' zones). In this case, disks can form only around virtually stationary Kerr and Schwarzschild BHs.