"Upper limit" on the characteristics of "Singularity" I know GR fails in "singularities". Is there an upper limit on characteristics of the singularity like a maximum value for the density of matter after which GR fails? I came across a number of threads which discuss what happens after something falls inside a supermassive black hole and it seems that GR holds well inside these objects within the event horizon. I would like to know the limits of GR, or in other words, at what point exactly does GR begin to fail in explaining the characteristics of matter that falls into the said supermassive blackhole? Hope I made myself clear.