https://en.wikipedia.org/wiki/Gravitational_singularity The two most important types of spacetime singularities are curvature singularities and conical singularities. Singularities can also be divided according to whether or not they are covered by an event horizon (naked singularities are not covered). According to modern general relativity, the initial state of the universe, at the beginning of the Big Bang, was a singularity. Both general relativityand quantum mechanics break down in describing the earliest moments of the Big Bang, but in general, quantum mechanics does not permit particles to inhabit a space smaller than their wavelengths. Another type of singularity predicted by general relativity is inside a black hole: any star collapsing beyond a certain point (the Schwarzschild radius) would form a black hole, inside which a singularity (covered by an event horizon) would be formed, as all the matter would flow into a certain point (or a circular line, if the black hole is rotating). This is again according to general relativity without quantum mechanics, which forbids wavelike particles entering a space smaller than their wavelength. These hypothetical singularities are also known as curvature singularities. What are the singularities inside Black Holes, are they physical or purely mathematical, i think AFAICR That the main consensus is that the universe did not start from a singularity, so that leaves Black Holes as the last bastion for a possible physical thing inside an event horizon, if it is not physical what has hapend to the millions of sun masses consumed by the Black Hole ?