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We argue that one of the basic assumptions of the Bondi accretion process,that the accreting object has zero pressure, might not hold in many galaxiesbecause of the pressure exerted by stellar winds of star orbiting the centralsuper massive black hole (SMBH). Hence, the Bondi accretion cannot be used inthese cases, such as in the galaxy NGC 3115. The winds of these high-velocitystars are shocked to temperatures above the virial temperature of the galaxy,leading to the formation of a hot bubble of size ~0.1-10 pc near the center.This hot bubble can substantially reduce the mass accretion rate by the SMBH.If the density of the hot bubble is lower than that of the interstellar medium(ISM), a density-inversion layer is formed. As the gas loses energy by X-rayradiation, eventually more mass of the cooling shocked stellar winds will beaccreted to the SMBH. This accretion will be of cold clumps. After a period ofmillions of years of low AGN activity, therefore, a stronger AGN activity willoccur that will heat and expel gas, much as in cooling flow clusters. Adding toother problems of the Bondi process, our results render the Bondi accretionirrelevant for AGN feedback in cooling flow in galaxies and small groups ofgalaxies and during galaxy formation.

Suppressing hot gas accretion to supermassive black holes by stellar winds