So, according to physicsoftheuniverse.com, "In the centre of a black hole is a gravitational singularity, a one-dimensional point which contains infinite mass in an infinitely small space, where gravity become (sic) infinite and space-time curves infinitely, and where the laws of physics as we know them cease to operate." Now, if my understanding is correct (and I doubt it is), the previous state of the black hole was that of a star of a mass which has the potential to yield a black hole once that star has died. Obviously, while the star is alive, its mass is finite, its gravitational pull is finite and the manner in which it curves space-time is finite. What exactly happens that causes these variables to become infinite? I can picture them becoming arbitrarily large, but infinity is not about growing or shrinking drastically in size; it's not about any particular numerical value at all. Furthermore, I find it confusing that we know it is infinite, because what indicates this? If you measure something, shouldn't the result be a finite value? How could you possibly measure something and conclude that it is infinite in a particular regard?