Albert Einstein did not explicitly discover or predict black holes as they are currently understood. However, his work in the field of general relativity laid the foundation for our understanding of black holes.
In 1915, Einstein formulated his theory of general relativity, which revolutionized our understanding of gravity. General relativity describes gravity as the curvature of spacetime caused by mass and energy. It predicts the behavior of massive objects and the curvature of spacetime around them.
Within the framework of general relativity, a physicist named Karl Schwarzschild, in 1916, found a solution to Einstein's equations that described a highly concentrated mass in a small volume of space. This solution is now known as the Schwarzschild solution and represents a non-rotating and non-charged black hole.
At the time, it was not clear what the implications of the Schwarzschild solution were, and the term "black hole" had not yet been coined. It was not until much later that the concept of black holes emerged.
In the 1960s, scientists like John Wheeler and others began to explore the consequences of Einstein's theory in extreme conditions. They realized that under certain circumstances, massive stars could collapse under their own gravitational pull to form incredibly dense objects with an intense gravitational field from which nothing, not even light, could escape. This concept was eventually named a "black hole" due to its properties.
The study of black holes has since become a prominent area of research, combining theoretical physics, observational astronomy, and astrophysics. While Einstein's work on general relativity did not explicitly predict black holes, it provided the mathematical and theoretical framework necessary for their subsequent discovery and study.