Albert Einstein is hailed as the father of modern physics due to his groundbreaking theories that transformed our understanding of the universe. His most notable contributions include the theory of relativity, particularly the equation E=mc², which expresses the equivalence of mass and energy. Einstein's work fundamentally changed how we comprehend space, time, and gravity, providing insights into phenomena such as black holes and the expansion of the universe. His ideas not only advanced theoretical physics but also had significant implications across various scientific fields, influencing technology and our philosophical outlook on reality.