Growth of Supermassive Black Holes in a Decaying Vacuum

The appearance of supermassive black holes (SMBHs) within approximately the first 800 million years after the Big Bang remains subjects of intense scrutiny and debate. On the other hand, a dynamical vacuum energy density has been proposed as a possible solution to the cosmological coincidence problem. It is natural to expect that a dynamical vacuum energy could affect the evolution of black holes. In this work, we investigate the rapid SMBH growth in a decaying vacuum cosmology with a time-varying cosmological constant. Since the vacuum energy is constantly decaying into particles, newly generated particles inside the event horizon may contribute to the growth of black holes. This scenario may offer novel insights into the formation and growth of SMBHs.