1.   The universe might then have re-expanded without going through a state of infinite density.

2.   The work that Penrose and I did showed that they would continue to collapse until they reached a singularity of infinite density.

3.   Would it collapse to infinite density?

4.   In the beginning, according to this model, mass was compressed into a state of infinite density, an initial singularity.

5.   A massive black hole is thought to be a point of such infinite density and gravitational strength that nothing can escape from its grasp.