James Clerk Maxwell made significant contributions to the understanding of electromagnetism in the 19th century. His work mathematically described the behavior of electromagnetic waves, including light, and formulated the famous Maxwell's equations. These equations demonstrated that electromagnetic waves propagate through space at a constant speed, which happened to be consistent with the measured speed of light.
However, while Maxwell's equations provided a mathematical framework for electromagnetism, they did not directly address the behavior of light in relation to observers in motion. Maxwell himself did not fully explore the implications of his equations in the context of different frames of reference or the nature of time and space.
It was Albert Einstein who developed the theory of special relativity in 1905, building upon the foundations of Maxwell's equations and other earlier works. Einstein's theory introduced revolutionary concepts, such as the constancy of the speed of light in all inertial reference frames and the interrelation of space and time.
Einstein realized that the constancy of the speed of light, as predicted by Maxwell's equations, had profound implications for our understanding of the nature of space and time. He formulated the principle that the laws of physics are the same in all inertial reference frames, leading to the development of special relativity. This theory described how physical phenomena, including the behavior of light, change when observed from different frames of reference.
Einstein's theory of relativity encompassed a broader understanding of the universe, addressing the relationships between space, time, and motion in a consistent and coherent framework. While Maxwell's equations provided the basis for the constancy of the speed of light, it was Einstein who extended and refined these concepts to formulate the theory of relativity.