First do we have anyway to even estimate the mass of the entire universe? And then is there any data that shows mass being gained or lost? Would we ever know if someone was playing with the til.
What is the most accurate method for SMBH mass estimation? In the literature I could find 5 methods : (1) Marconi & Hunt 2003, (2) Hu 2008, (3) Gultekin et al. 2009, (4) Graham 2007, (5) McLure ...