David Hilbert, Henri Poincaré, and H.A. Lorentz made significant contributions to the development of the theory of relativity, particularly in the context of the special theory of relativity. It is important to note that the work of these scientists was not a failure, but rather part of a collective effort that contributed to the formulation of the theory. However, there are a few aspects where Einstein's approach differed and eventually led to the development of special relativity as we know it today. These include:
Conceptualization of the theory: While Lorentz and Poincaré made important contributions to the understanding of electromagnetic phenomena and the Lorentz transformations, they approached the problem within the framework of an aether theory. They postulated the existence of an aether as the medium through which electromagnetic waves propagate. Einstein, on the other hand, did not rely on the existence of an aether and developed the theory based on the principles of relativity and the constancy of the speed of light in all inertial frames.
Principle of relativity: Poincaré and Lorentz independently proposed a form of the principle of relativity, which states that the laws of physics should have the same form in all inertial frames of reference. However, Einstein formulated the principle more explicitly and generalized it by incorporating the constancy of the speed of light in all inertial frames. This led to the development of the theory of special relativity, where the laws of physics are invariant under Lorentz transformations.
Relativity of simultaneity: Einstein introduced the concept of the relativity of simultaneity, which states that the ordering of events can be different for observers in relative motion. This was a departure from the classical notion of absolute simultaneity. Lorentz and Poincaré had not explicitly addressed this concept in their work.
Independence of space and time: Einstein's formulation of special relativity emphasized the idea that space and time should be treated as a unified entity, known as spacetime. This concept was not as explicitly emphasized in the works of Lorentz and Poincaré, who treated space and time as separate entities.
It is important to recognize that scientific progress often involves the contributions of multiple individuals, and the development of special relativity was no exception. Einstein's unique approach and insights, combined with the contributions of Lorentz, Poincaré, and others, played a crucial role in the formulation of the theory as we understand it today.