- #1

PeterDonis

Mentor

- 40,685

- 18,366

Most people who have spent any time at all studying GR are familiar with the Schwarzschild solution. (A series of Insights articles discusses the key properties of that solution.) Much of that familiarity probably derives from the fact that the Schwarzschild solution describes a black hole. However, for some reason, much less attention is paid to the simplest solution that actually describes the collapse of a massive object to a black hole. This solution was discovered by J. Robert Oppenheimer and Hartland Snyder in 1939 and is called the Oppenheimer-Snyder model. In this article, we will briefly sketch how this model is constructed, and examine its key properties.

Our starting point is an idealized massive object which is perfectly spherically symmetric, with constant density in its interior, of finite extent, and surrounded by vacuum. Of course, such an object is highly unrealistic. But it makes the math tractable, in the sense that we can actually find closed-form solutions for...

Continue reading...