19391776 Club
Oppenheimer's Paper Gives Physics Its First Black Hole
Oppenheimer and his student Hartland Snyder show a dying star can seal itself off from the universe entirely.
On September 1, 1939, the Physical Review published a paper by J. Robert Oppenheimer and his graduate student Hartland Snyder titled "On Continued Gravitational Contraction." Using Einstein's own general relativity, the two Berkeley physicists showed that a sufficiently massive star, once it burned through its thermonuclear fuel, would keep collapsing under its own gravity until it vanished behind an event horizon, a boundary that trapped even light. The paper arrived months after Einstein himself had argued such objects were mathematical fiction, not physical reality…
