What was George's lemaitres major contribution to the current understanding of the universe?

Georges Lemaître's major contribution to our understanding of the universe was his formulation of the Big Bang theory, which proposed that the universe began as a singular, dense point that expanded over time. He was the first to suggest that the universe is continuously expanding, a concept supported by later observations, such as those by Edwin Hubble. Lemaître's work laid the foundation for modern cosmology, integrating concepts from physics and astronomy to explain the origins and evolution of the universe. His insights helped shift the scientific perspective from a static universe to one that is dynamic and ever-changing.