The reason why the speed of light is considered an absolute cosmic speed limit in our current understanding of physics is deeply rooted in the principles of relativity and the structure of space and time.
According to the theory of special relativity, proposed by Albert Einstein, the speed of light in a vacuum is constant and the same for all observers, regardless of their relative motion. This constant speed of light is a fundamental postulate of the theory and has been extensively tested and confirmed by experimental observations.
The theory of special relativity also introduces the concept of spacetime, which combines the three dimensions of space with the dimension of time into a unified four-dimensional framework. It states that the laws of physics should remain the same for all observers who are moving uniformly with respect to each other.
If an object were to exceed the speed of light, it would violate the principles of special relativity. As an object with mass approaches the speed of light, its relativistic mass increases, and it would require an infinite amount of energy to accelerate it to or beyond the speed of light. This implies that it is not possible for an object with mass to reach or exceed the speed of light.
From a deeper perspective, the speed of light is closely tied to the structure of cause and effect in the universe. It establishes a universal limit on the transfer of information and energy. If an object could travel faster than light, it would, in principle, allow for the violation of causality, enabling effects to occur before their causes—a contradiction to our understanding of cause and effect.
The preservation of the speed of light as an upper barrier is not a matter of the universe "wanting" to enforce it, but rather a fundamental feature of spacetime and the laws of physics as we currently understand them. The theory of relativity provides a robust and consistent framework that explains the behavior of space, time, and the propagation of light and other physical phenomena. While the theoretical exploration of concepts like wormholes or warp drives continues, their realization would require a profound revolution in our understanding of physics.