According to the excerpt, how does Karl Schwarzschild use Einstein’s ideas to draw a conclusion?

Karl Schwarzschild was a German physicist and also an astronomer. He is regarded as the father of astrophysics.

Albert Einstein was also German-born theoretical physicist. He was known for developing the theory of relativity.

Karl Schwarzschild used Einstein's ideas about space bending to reach a conclusion that black holes are possible when stars spin at a high speed and eventually collapse.