In star: Black holes …collapses to a black hole—a singularity, or point of zero volume and infinite density hidden by an event horizon at a distance called the Schwarzschild radius, or gravitational radius. Bodies crossing the event horizon, or a beam of light directed at such an object, would seemingly just disappear—pulled into a… Read More
work of
Penrose
In Roger Penrose …black hole collapses to a singularity, a geometric point in space where mass is compressed to infinite density and zero volume. Penrose also developed a method of mapping the regions of space-time surrounding a black hole. (Space-time is a four-dimensional continuum comprising three dimensions of space and one of time.)… Read More
Schwarzschild
In relativity: Black holes …in a vanishingly small volume—a singularity—gravity will become so strong that nothing pulled into the surrounding region can ever leave. Even light cannot escape. In the rubber sheet analogy, it as if a tiny massive object creates a depression so steep that nothing can escape it. In recognition that this… Read More