Crisis in Newton's law of Gravitation

Newton's law of Gravitation was a very successful theory. It was tested by many people many times and it always proved true. But, it was not the final theory. It also has some faults and some of them were known to Newton.

At first many of Newton's contemporaries found the idea of attraction between two objects through empty space unintelligible. Newton provided an escape by imagining that gravitational attraction is caused by the exchange of some massless particle called graviton but he explained no further.

Another problem was number of stars in the universe. According to Newton the number of stars in the universe should be infinite because a finite number of stars would eventually collapse at some point due to gravitational attraction. Later Heinrich Olbers argued that infinite number of stars would make the night-sky so bright like day.