On the heels of Einstein’s general theory of relativity, German theoretical astrophysicist Karl Schwarzschild provided a detailed proposal on the existence of black holes in 1916. The concept of black holes goes all the way back to the 1780s, when John Michell and Pierre Simon Laplace envisioned “dark stars” whose gravity was so strong that not even light could escape. As with many startling ideas, the acceptance of black holes as real objects took a long time.
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